u 60-21918 PRICE $2.50 SOVIET RESEARCH AND DEVELOPMENT IN MASS TRANSFER CHEMICAL ENGINEERING UNIT OPERATIONS Distributed by U.S. DEPARTMENT OF COMMERCE OFFICE OF TECHNICAL SERVICES WASHINGTON 25, D. C. PAL 60-16 TRANSFER CHEMICAL EHGIHEERING UNIT OPERATIONS 1 March i960 Digitized by the Internet Archive in 2012 with funding from LYRASIS Members and Sloan Foundation http://archive.org/details/sovietresearchdeOOwash COITEOTS Page INTRODUCTION .•••••••••••••••••••••• 1 ABSORPTION . . . • » * • . * o . . o . * o e - Theoretical Considerations. • •««o««*«, •••••••• * Practical Considerations ......... ........<>. o References - Absorption ...............<><><><> 12 ADSORPTION oec>ao«e*a*ooeoo«eoooeooooooo 18 Studies of Adsorbents . . . . . . . . . . <» . . . . . . <» <» <> 18 Adsorption Equilibria and Rates ............... 22 Adsorption in Catalysis ....... ............ 26 Clienii SOrptiOn o..«..oooooooooo.oooo«eo C J Experimental Techniques ... ............... . 28 Industrial Applications . . . . o » . . . . . . . » . . . 29 References - Adsorption ................... 3^ OiTiXOiAJuijiZiAi JLUiVi o©o©.©o»o.oooo«oooooeooooo S^- OrVS wct_l_ u 1 ! OWuH .0«o.ooaoo..oooooooooooe ^.D OJ/yS'OaJ- OySueiUS « o » o o . o ooooooo.o.oooo.o U(^. Habit Modification of Crystals . . . . . . ...... <> . . . 64 Crystallization Apparatus and Methods for Growing Crystals. . . . . . <> . . ....... . 67 References - Crystallization . <» . . . • • . . . . ...<,. . 72 J-iA.jLXlA-OXXvJI'I eoooooeeeo*oooooeooooocooo«o Q._ Theory and Calculation Methods. .„„„...,.„....„ 82 Equilibrium Studies ............ . ....... . 83 Extraction Processes. .................... 85 Extraction Equipment. .................... 87 References - Extraction ................... 8w APPENDIX A. Key to Journal Abbreviations. ............ 100 APPENDIX B. Principal Soviets Authors on Mass Transfer Research and Development ................... 103 Table Recent Soviet Studies of Extraction Equilibria .......... 107 - iii - SOVIET RESEARCH AND .il TRANSFER CHEMICAL ENGINEERING I IT OPERATIONS INTRODUCTION This report is concerned .-with.. Soviet capabilities in the cheraical engineering unit operations of... absorption, (gas to liquid), adsorption (gas or liquid to s olid) , .crysta3iiaatixin...( liquid. to solid) and extrac- tion (liquid or solid to liquid),, It is based on open Soviet technical literature of the period 195>0-59 • The search for references and abstracts covered appropriate volumes of Chemical Abstracts , Monthly Listj^^usslan Accessions (Library of Congre¥sT7^®^^icsl"'J a ranslations "X&ad .its predecessor, Translations Monthly ) , Sc^ntiMg^I^^gB^±on_^p^rtg and the Chemistry Section of Referatiynyy Zhurnal a The. .primary source, was £hemj£al M _Abstracts 5 since a complete collection of this periodical was at hand? complete files of the others were available only for 1958- and. 1959 o The years l^SS? were searched intensively and. all., appropriate. . Soviet papers notedj assuming a time lag of up. .to one. year,, this, means. ..the actual period of intensive search was. 195k- through 1958 ° ""Active 8 * authors (arbitrarily defined as those with five or . more. ..publications- ...in. the 1955-59 ■ period) were searched back to 195-0- -in Chemical. Abs.tr.acta, and. occasionally further to trace the development of. significant re search Discussion. has. heen.. divided into four, general, sections , corresponding to the mass transfer, .operations... surveyed*. . .These are further subdivided as appropriate to the subject matter An appendix, contains tabulation of the principal Soviat.-authorSj,... theix. .latest. .known -.institutional affiliations , and their areas of. specialty ABSORPTION Soviet work on the theory and practice of absorption has been improving steadily D The best research in this, area makes, good, use of modern mathemat- ical and experimental techniques 8 Recent literature also indicates growing interest and capability in the development of industrial processes and equip- ment. The following discussion is divided into theoretical and practical considerations „ Theoret ical Considerations An extensive series of articles of good quality has been published by Mo Kho Kishinevskiy and his co-workers in. the field of absorption processes „ These range from studies of practical significance. ..to. those which are highly theoretical D Many of the studies make . intensive use of the knowledge of techniques and practices of the Western world e Emphasis frequently is given to absorption in systems where -intensive. mj_xing is encountered,, For example , Kishinevskiy, Ao V. Pamfilov, and M. A„ Kerdivarenko have studied the absorp- tion of carbon dioxide by solutions of sodium hydr iad.de and sodium carbonate under high-speed agitation «. 1/2/ A closed system was used, and rate of absorption was determined, by recording decrease of. pressure in the vapor phase They developed, .a. .general., e4nafci.0n.-f or ..the kinetics of the absorption process , which gave the parameter modifications as functions of the degree of turbulence in the reacting phase «, 3/ Consideration of mass flow transfer occurring across a surface boundary during absorption , was used by Kishinevskiy .to develop, a general equation that is valid for first-order reactions and holds over a wide range of turbulence, mere s-pm pis the flow of material across the boundary per unit time, he has l ttiat? snown dw MC /"l-e ~( ? ~ 73?P X |) m °^ 7 , chemical absorption, had not been adequately developed, A method was proposed by Mochalova and Kishinevskiy for calculating the height of absorption towers. By use of this method, equipment can be designed to absorb a component from the gaseous mixture to a prescribed degree and to give a liquid of a definite concentration, 17/ M, Ye Q Pozin and his several co-workers have carried out a series of studies on absorption with chemical reaction, i, e,, chemical absorption, to develop a theory of such a process. Some of the systems investigated were sulfur dioxide and sodium carbonate; ammonia and sulfuric acidj and carbon dioxide and potassium hydroxide , 18-20/ With Ye, S„ Tumarkina, Pozin. also studied bromine and sodium hydroxide; bromine and sodium carbonate; bromine and ferrous bromide; and bromine and ferrous bromide, 21/ Whenever the chemical reaction of a gas with a solution is reversible and attains equilibrium before stoichiometric completion, the chemical capacity of the absorbent is not reached but the effective concentration of the absorbent acts apparently smaller. Equations were developed by Pozin to explain these phenomena, 22/ He also derived equations to ex- plain gas absorption with crossed flows of gas and liquid by assuming that the concentration of the absorbed component in the gas varies linearly with the length of the path. The derived equations are standard and advance no new concepts, 23/ Pozin, I, P„ Mukhlenov and Ye, Ya, Tarat found the conditions of absorption in a sieve-plate apparatus are determined primarily by the flow rate of the gas stream. This bubbling process then passes quickly into a foaming process , wherein mass transfer proceeds more vigorously in the layers of dynamically fluidized foam consisting of films and liquid mixed with the gas bubbled,, 2k/ Pozin is continuing . his studies of absorp- tion under foaming conditions, having reported recently with B„ A Kopylev and No A. Petrova on the efficiency of a four-plate apparatus for ammonia absorption in copper-ammonia solution,, 25/ This work, though incomplete, is promising o In the extensive literature on absorption of gases by liquids, attention has been devoted to rates of the process while relatively little emphasis has been given to the degree of reaction of the absorption process components o Pozin and B„ A. Kopylev stated that the efficiency of absorp- tion depends on both the rate and the degree of inter-reaction „ An approx- imate equation, derived for crossflow of a gas and liquid, established the relationship between absorption efficiency, absorption coefficient, and linear gas velocity? 2K n " 2W*>T where , n is the fractional efficiency of the plate (or tray) with respect to the gas | K is the total absorption coefficient j and, ¥ is the linear velocity of the inert component of the gas stream,, Using this equation and experimental data, they proved that the absorption efficiency in bubbling and foam equipment was determined mainly by the solubility of the gas in the liquid, while other factors (linear gas and liquid velo- cities, height of the bubbling or foam layer, etc) varied the efficiency only within definite limits «, 26/ To demonstrate their chemical absorption theory Pozin and his associates also used other sustems of interests nitrogen ozides and calcium hypo- chlorite! hydrogen sulfide and ar senate-carbonate solutions „ 27/ 28/ These articles are good and emphasize the importance of these new penetra- tion concepts o V„ V Kafarov has analyzed several sets of data on the absorption of carbon tetrachloride by benzene,, His. analysis led him to conclude that free turbulence approaching emulsification, i <,€<>, the range of turbulence where the Reynolds Number is independent of the Peclet Group, was essential for the scaling up of two-phase systems » 29/ In a continuing analysis and review, Kafarov and Yu I. Dytnerskiy arrived at a similar conclusion. 30/ The two-film theory for mass transfer processes was criticized by Kafarov because "the film theory ignores the hydrodynamic conditions process, as strictly defined conditions are laid down — the presence of molecular diffusion, which,, as is known, can only be significant in stationary layers or in layers moving at low velocities „" With the development of free turbulence and the formation of eddies a+ the interface, conditions are set up, depending on the hydrodynamics, in which the coefficients of turbulent diffusion may increase to a point where molecu- lar film transfer may be neglected,, In absorption processes (with moving two-phase streams), the mass transfer was expressed by him as? _ = J]] + R ff ) * q \v T **gj g— in which, q is the mass transferred! D is the molecular diffusions. Eg is the turbulent transfer component $ dC is the concentration change over a transfer distance dx a If one defines s K = D * Eg, then the former equation is reduced to? q ■ K £\/l 9 in which K represents both the molecular and turbulent mass transfer over the finite lengthy L In order to apply these generalizations to an analysis of diffusion processes, Kafarov stated that the determining criterion for mass transfer should be one for turbulent mass transfer , i.e , a modified Peclet number 31/ This theory was further expanded by Kafarov to an analysis by use of similitude principles so that the experimental results could be transferred to the design of industrial processes „ 32/ 33/ Kafarov and V,, I Trofimov have analyzed a series of experiments on absorption of ammonia, sulfur dioxide, acetone, ethanol and carbon dioxide by water in packed towers „ They conclude that free turbulence begins at an "inversion point," where the gas passes from the continuous phase to the dispersed phase and liquid passes from the dispersed phase to the continuous phase 3ij/ 35/ Consideration of these analyses and theories was developed by Kafarov and L I* Blyakham into a Soviet patent „ The most valuable claim can be stated as follows? Conditions are created which cause emulsification within the packed column The yields per unit volume for absorption, rectification and heat or mass exchange are increased by this method*, 36/ L„ Do Berman also expostulated against the use of the traditional, stationary two-film concept in analyzing mass transfer processes, ± s e 0$ absorption processes Speaking of the total resistance to mass transfer as equal to the sum of the partial resistances of the liquid and gas phases, he stated? "Such a division, which has an adequate physical basis } of the total resistance into its components does not require the introduction of a concept of fictitious gas and liquid films oooThis concept of equivalent or derived films, which has penetrated into our literature from foreign sources, presents no advantages, but is harmful because it distracts attention from a correct evaluation of the actual hydrodynamic conditions and in consequence it sometimes leads to erroneous conclusions o" 37/ Even though the Soviets object to the "two-film" concept, valuable correlations have resulted from its use Many investigators have stressed the importance of the similarity of mass exchange and heat transfer, assuming a fixed phase interface,, Berman pointed out the applicability of this similarity in some practical cases but warned that the peculiarities in mass exchange (such as transverse flow of components, molar flow of substance, and turbulence in the interface layer) destroy much of the similarity between the mass exchange process and the heat transfer process „ He confirmed this new criterion equation by the use of experimental data, developed by him and others 38/ This equation is important o The process of absorption with chemical reaction was carefully described by A. M„ Rosen, who used it to develop a method of calculating isotope exchange in the following reactions? <=6= J^O + J C0 2 16 - Hgtf 16 * | C0 2 18 His explanation was intriguing, and his study has potential valuable implications o 39/ In absorption processes, wherein mass transfer takes place between a soluble absorbate in a cavity of a gas bubble and the liquid around it, hydro dynamic considerations govern the shape and dimensions of the bubbles „ Ladyzhenskiy presented an excellent mathematical discussion of this phenomenon that is important in ^bubbling 81 absorption „ From this study he concluded that the shape of a spheroidal bubble ascending in a still liquid is determined mainly by gravitational forces,, hoj A good mathematical development of kinetic equations for the absorption process, when reversible chemical reactions take place in the absorbent, was presented by I„ G. Plit„ I4I/ He considered the kinetics of absorption of carbon dioxide by potassium carbonate from the above point of view as represented by a film consisting of neutralized and non-neutralized zones „ Earlier studies by Plit, working with Ko N. ShishkLn, covered the absorption of carbon dioxide by a bubble of foam rising from a potassium carbonate solution,. Their results showed that an increase of foam agent (saponin) concentration increased the absorption rate of carbon dioxide by the solution, 1*3/ Plit also described very clearly the kinetics of "stripping" (de sorption) of hydrogen sulfide from the absorbent (potassium carbonate and potassium bicarbonate solution) The rate of de sorption fell rapidly after the initial stripping period but increased as the total heat imput was increased „ i\hj \\%f . Further evidence was advanced by V M. Ramm and A Yu„ Zakgeym to show that the two-film theory of absorption can not be corrected or proved* They stated that the non-stationary diffusion theory, which assumes that fresh liquid moves to the interface and removes liquid that has already interacted with the gas, is more exact, Calculations were suggested for design characteristics of packed (spray type) and of bubble plate (sectional type) absorption equipment by V M Govorkov and Ya„ D Averbukho They emphasized that, in the first type, there is a continuous and monotonous change in the driving force; and, in the second type, there is a ^step 9 ' change in the driving force „ There- fore, in the latter type, the design must be calculated by graphical methods, w A relationship was established between the mass transfer coefficient in the gaseous phase and the volumetric velocity of the gas and the depth of immersion by G. N. Gasyuk, et al„ J48/ In general, it can be stated that the Soviet theoretical work is good, even though it is argumentative on the value of the "two-film 11 concept _7« Practical Considerations Many articles of practical . significance have been published in recent Soviet literature „ Of these, the studies of S„ N c Ganz and his co-workers on nitrogen oxide absorption for production of nitric acid and for recoveiy of nitrogen oxides used in the lead chamber production of sulfuric acid are the most extensive and important „ Recovery by absorption of nitric oxide in ferrous sulfate solutions was investigated by Ganz and L, I c Mamon over a wide range of operating conditions? nitric oxide concentrations in gas and solution j ferrous sulfate concentration! temperature; gas flow ratej and solution rate Optimum conditions were determined for efficient recovery,, h9f With S Bo Kravehinskaya, Ganz studied the absorption rate of nitrogen oxides in solutions of calcium hydroxide in a revolving plate absorber The rate increased rapidly with the peripheral speed of the plates « They calculated that the construction cost and operating energy of a revolving absorber are 10 percent and 38 oh percent of an equivalent capacity packed tower, 5>0/ The rate and completeness of the conversion of nitrogen oxides into nitric acid depends upon a number of factors including temperature, the concentration of nitrogen oxides in the gas, degree of oxidation, concen- tration of absorbing acid, and liquid and gas rates „ This multiplicity of factors makes the kinetics of nitric acid formation a very complex process o Ganz, M„ A, Lokshin,. and S c I„ Kapturova developed equations that account for the effect of the major factors in the absorption of nitrogen oxides by aqueous solutions of nitric acid From these equations, the coefficient of the absorption rate can be calculated Use of these also permits calculation with adequate accuracy of the dimensions of a horizontal mechanical absorber for production of nitric acid 5l/ The efficiency of absorption. of nitrogen oxides is important in procudtion of nitric acid 9 The effectiveness of a revolving absorber for the absorption of nitrogen oxides by sulfuric acid was also investigated by Ganz The absorption efficiency of the nitrogen oxides increased with the peripheral velocity of the plates, with the acid concentration,, and with the nitrogen oxide concentration,, It decreased with an increase in the rate of gas flow and the acid temperature „ %2.J Solutions of ferrous sulfate have been used to decontaminate gases containing nitrogen oxides and to return the nitrogen oxides (concentrated) into the production process „ Ganz and Mamon studied this system of chemisorption They showed that the coefficient of absorption of nitric oxide increased in proportion to the 0„8 power of the gas velocity, and that the gas film coefficient was controlling „ The design of industrial absorption equipment was simplified by application of these data 53/ They further proved experimentally that vigorous mixing of the nitric oxide and ferrous sulfate solution in mechanical absorbers markedly increased the absorption rate This improved the efficiency and made the process of practical importance for the recovery of nitric oxides and for the elimination of air pollution « The influence of hydrodynamic conditions on the rate of absorption of nitrogen oxides by the milk of lime was studied in a high-speed mechanical absorber in a semiworks unit by Ganz, with the use of industrial gas from a nitric acid plant. He found that the absorption rate increased rapidly with the increase of the peripheral mixing disc speed up to an optimum value o Above this value the rate decreased,, The space velocity of the gas was another important hydrodynamic factor that determined the rate of the process o The rate rose rapidly to a maximum. with the increase of the space velocity to an optimum value? it then decreased, g>/ These results seem to indicate the practical., application of the Soviet surface renewal theory of absorption Numerous investigators have shown that the most effective way of accelerating mass transfer processes between gases and liquids in direct contact is to increase the turbulence of the system Ganz correlated the data of these investigations to derive general laws and design character- istics of high-speed rotary absorbers He showed that the following hydro- dynamic conditions are most favorably obtained by highspeed rotary absorbers s extensive area of phase contact, impact effect of the drops 9 intensive friction between the gas and the liquid, and rapid hydrodynamic transfer of the inter- acting components o 56/ Ao N. Fernovskaya and A„ P Belopoi%kiy found the absorption of sulfur dioxide in water was decreased by surface-active agents This decrease was independent of gas velocity at constant liquid rates and was not affected by temperature,, The surface=action agent modified the hydrodynamic conditions in immobile layer of the liquid for liquid film controlling diffusion,, 57/ For absorption of ammonia in water, in which system the gaseous diffusion layer was controlling , they learned that no reduction in the rate of absorp- tion was caused by surface -action agents „ The reverse was true for carbon dioxide-water systems, in which the liquid diffusion layer was controlling,, £8/ These results indicated the possibility of a method of determining which layer, i a e Q , gas or liquid, was diffusion controlling in any given system,, A series of studies were carried out by T. A, Sarukhanyan and Belopol 8 skiy on the absorption of carbon dioxide by aqueous ammonia solutions „ Their experimental data showed that the absorbed carbon dioxide was mainly consumed in the reversible reaction of ammonium carbonate formation and that, at any given instant, an equilibrium existed between carbon dioxide and ammonia. $9/ I No Kus'minykh et al„ presented data on the recovery of nitrogen oxides by absorption in soda and lime solutions. These data showed that increased basicity of the solutions improved efficiency of absorption. 60/ The reaction of sulfur dioxide and ferric sulfate during an absorption process was studied by Ku2i s minykh and To B. Bomshteyn who sought to develop the kinetics of the raction and to improve the efficiency of recovery,, 61/ Absorption of sulfur dioxide in solutions of calcium and magnesium bisulfite solutions is an important phase of paper mill operation. Data presented by Kuz c minykh and M, D. Babushkina were more complete and usable than those presented by earlier investigators, 62/ Kuz'minykh and several co-workers have been investigating mass transfer efficiency in plate columns,, One of their papers reports coefficients of mass transfer in both the gas and liquid phases on horizontal perforated plates at varying gas velocity were measured for the evaporation of water and desorption of oxygen from water solution Gas velocities up to 1.8 meters/ second were studied and the gas-phase coefficient was reported as proportional to the o 8$ power of velocity «. The liquid phase coefficient reached a maximum value of between o 5> and o 6 meter/second (gas velocity) and then dropped to a constant value (about one-half the maximum) above 1 meter/ second, 63/ In another paper, Kuz'minykh and two co-workers examined the absorp- tion of nitrogen oxides in a plate column,, They showed the efficiency coefficient for each plate decreased as the absorbent became richer and the gas poorer in absorbate 6k/ A. S. Bukhman and K„ M Malin investigated the absorption of nitrogen oxides in sulfuric acid They found that increas- ing the linear velocity of gas flow increased the rate of gas absorption up to an optimum value s above which the rate remained constant 65/ These experimental results , well-known to theoreticians, are of practical importance, Malin and Bukhman applied the film theory to their data on absorption of nitrogen oxides in sulfuric acid„ A simple formula expressed their datas Na - Kg +^Pg inhere, Na was the amount of nitrogen oxides absorbed per unit timej Kg was the coefficient of the absorption rate 3 and /Pg was the partial pressure difference for the nitrogen oxides a 66/ Using a wetted wall tower for this system, they proved that the liquid film resistance was negligible 67/ They al3o proved that in a wetted wall tower, where the resistance pf the gas film was controlling^, the driving force for the absorption was the sum of the partial pressures of the nitrogen oxides in the gaseous phase 68/ Ferric hydroxide has been long used to absorb hydrogen sulfide from commercial gases — either to purify the gases or to recover the hydrogen sulfide o While the chemistry of this process is well -known 5 the kinetics of the absorption have been poorly defined,, M Q D„ Kuznetsov and A. Ye e Sagalovskiy studied this process and showed that the absorption of hydrogen sulfide by ferric hydroxide was a heterogeneous reaction, involving kinetic and diffusional stages, that took place with the formation of a layer of reacted material „ The principal resistance to the rate of reaction was brought about by the slowness of the diffusion of hydrogen sulfide through the reacted material 69/ With Ye V. Popova, these scientists investigated the absorption of ammonia from coke-oven gas by sulfuric acid in a Venturi-type sprav -10- apparatus o They found 99,8 percent of the ammonia could be recovered by- using a larger amount of absorbent and by increasing the gas velocity in the Venturi spray heads, 70/ G, D, Sirotkin and V.V„ Star os tin determined the absorption of nitric oxide by aqueous solutions of ferrous sulfate and ferrous chloride and showed the equilibrium constant, K, was expressible by? K * V/(22„l*-V) P NO where , V is liters of nitric oxide absorbed by one mol of ferrous iron 71/ Sirotkin 8 s study of the absorption of nitric oxide by the complex of ammonia-cobalt solutions demonstrated the efficiency of this absorbent, 72/ Disc absorbers were designed by N. I, Timkin for sulfur dioxide and sodium sulfide interaction to produce sodium thiosulfate and to replace absorption columns In comparison, the disc absorbers were more efficient than the towers, even at lower power consumption 73/ Hydrogen sulfide is industrially recovered in order to avoid its nuisance in the atmosphere and to recover its value Equilibrium data were determined and presented for the first time by A. G„ Leybush and A. L„ Shneyerson for the absorption of hydrogen sulfide from its mixture with carbon dioxide in monoetbanolamine and diethanolamine They showed that hydrogen sulfide could be removed from the gas to a content of less than 0o0002 percento JbJ This would give a good recovery system. In order to remove and recover hydrogen sulfide, an investigation was made by I. L. Mar'yasin on the effect of various factors on the efficiency of purification of waste gases from gasoline refineries „ His results indicated that the temperature of the system and the method of absorption were the most important variables , 75/ M S. Litvinenko and S. P„ Lundin calculated and correlated the free energies of the reactions of various absorbents for hydrogen sulfide with a bsorption«de sorption efficiencies . They concluded that the optimum absorbents would have free energies between +15„6 and -l o 5 preferably near zero. 76/ S„ A. Bagaturov found gasoline (petrol) is sta- bilized in a combination absorption-de sorption system, wherein light hydro- carbon fractures are removed, 77/ G. V, Ponomarev developed equations for designing such systems of columns in multicomponent absorption and desorption processes. V. Bo Fal'kovskiy, Yu, I, Mel'nikov and A, V. Ventrova studied the effect of the dimensions of a column and of the gas velocity on the follow- ing important processes? absorption of ethylene and propylene in the alkylation of benzene? polymerization of isobutylene in sulfuric acid; and absorption of oxygen by aldehydes in the presence of manganese peracetate, Data were presented and correlated, 79/ Utilizing plan-parallel., iron plates as packing, Ya, V. Shvartsshteyn carried out an experimental, study on the recovery of nitrogen oxides from the waste gases of sulfuric acid production by absorption in sulfuric acido His results showed this packing was about 3o5 times more economical than ceramic ring packing, 80/ -11- Many mere references were reviewed Since they offered no new concepts and did not advance the state of knowledge of . absorption, no direct mention was made of them e In summary, the Soviet work. is. good theoretically and practical in its implications REFERENCES — ABSORPTION Kishinevskiy, M e Kh and Pamfilov, A. V„, "Absorption of Carbon Dioxide by Solutions of Sodium Hydroxide and Sodium Carbonate Under Conditions of Intensive Mixing," Zh.-PriML« Khim 3 22, 1183-90 (I9h9) 2 Q --— >, and Kerdivarenko, Mo A*, "The Kinetics of the Absorption of Carbon Dioxide by Solutions of Sodium Hydroxide in a High-Speed Propeller Agitator," J i- Agpl J!L _Chem 2 _(US^2, 2h 9 Uk9-$6 {1951) 3„ -«»-.«. 9 and Pamfilov, A. V«. "The Kinetics of Absorption," Zh P Priklo Khimii, 22, 1173=82 (191*9) ij ««.«,. 9 "The Kinetics of Absorption During Intensive Stirring, Zho Prikl Khimii, 2I4, 5142-5 (1951) a 9 5' .„„ 9 "Resistance of the Gaseous Phase in Absorption Processes 3 n Uch„ Zap, Ki shine vsko Un-t, 7, 21-5 (1953),* Ref Zh, a Khimiya, 6„ —««._, and Payer, So M„, "Absorption of Sulfur. Dioxide by Solutions of Potassium Hydroxide," ^J^^^M^s M> 579-83 (1953) 7 --<— , and Novik, R« M e , "Effect of Stirring on the Kinetics of Absorption of Carbonic Acid in Solutions. of Sedition Carbonate, 1 " Zh,_ Priklo KhlDiii, 26, 673-80 (1953) 8 — — , m The Work of Danckmerts in the Field of Absorption Theory," Zho Priklo Khimii, 27, 392=90 (195k) 9o Kishinevskiy, M« Kh , "Absorption Processes Accompanied by Second- Order Reactions," Zh a Prikl^Jhijaii, 27, li50-i (I9$k) 10 . «—-•., and Mochalova, Lo A , "Mechanism of Absorption Processes," Ucho .^g^^l^SSIg^. - IJ - ri -" fc - > 2k» 31=6 {19%) I Pef, Zho Khimiya 9 1956, 2793$ llo Mochalova, L A„ and Kishinevskiy, M. Kh e , "Kinetics of Bubble Absorption," Zh Q Priklo Khimii, 28, 30-39 (1955) 12 o Kerdivarenko, M A„j Migal, P a K c and Kishinevskiy, Mo Kli , "Kinetics of Absorption of Ethylene in Sulphuric Acid," Zh<, Priklo Khimii , 28_, U59-66 (1955) 13 o Kishinevskiy, M Zh G , "Regarding the Two Theoretical Analysis of Absorption Processes," Zho Priklo Khimii, 28, 927-33 (1955) -12- lil — — , and Mnchalova, L„ A., "Mechanism of Bubble Absorption," Zh a Priklo Khimii, 29, 170-5 (1956) 15 »-«,», "Effect of Stirring on the Kinetics of Carbon Dioxide Absorption by Solutions of Potassium Hydroxide , n Zhq Priklo Khimii ^ 30, lQS-9h (1957) 16 — «., "Determination of the Height of Packing in an Absorption Process Accompanied by a Chemical Reaction/' Zh e Priklo Khimii , 30, 1386-90 (1957) 17 o Mochalova, L. A. and Kishinevskiy, M a Kh., "On the Calculation of the Height of Towers for the Chemical Interaction of a Gas With a Liquid," Zh. Prikl. Khimii, 32 , No„ 1*, 785=789 (1959) 18 a Pozin, M Column/ 8 . Ye , "Absorption of S0^ by a Na«Co« Solution in a Packed KhiMe Prom-st", 6 Ii*~l8 2 (l9lili) 19 c -— , "Theory of Chemical Absorption. X„ The Criterial Equation of Mass Transfer Across the Diffusion Layer of the Gas in Scrubber Absorption/' Zh a Prikl Khimii, 21, No. 2, 218=26 (191*8) 20 o --—-•, "Rate of Absorption of Carbon Dioxide Gas bv Solutions of Hydroxides/ 8 Zh. Prikl^jfrimii, 21, No. 11, ll8lj-5 (192*8) 21. m^ and Tumarkina, Ye. S 0J) "Kinetics of Absorption of Bromine by Liquid Absorbents/ 1 Zh Priklo Khimii, 23 5 3964*08j J. Appl c Chem. (USSR), 23, 1*15=27 (1950) ~~ 22 o «=>—»- , "Velocity of an Absorption Accompanied by a Reversible Chemical Reaction/ 8 Zh. Prikl a Khimii, 21, 802-6 (191*8) > 9 ^Heat and Mass Transfer in Crossed Flow," Zh^_Prikl » Khimii , 25, 10324*1 (1952) 2k o -— , Mukhienov, I„ P. and Tarat, Ye e Ya , "Character of Gas-Liquid Dispersed System/ 9 Zh a Priklo Khimii, 30, 1*5=52 (1957) 25. »«»-»-., Kopylev, Bo A n and Petrova, N. A., "Ammonia Absorption by Copper- Ammonia Solution in a Foam. Apparatus , " Zh a Prikl. Khimii, 31 $ No. 7 3 1007-1012 (1958) 26. — — •», and Kopylev, B. A., "Effectiveness of Absorption of Gases of Different Solubilities by the Bubbling and Foaming Methods/' Zh. Prikl. Khimii, 30, 362-9 (1957) 27. Pozin, M„ Ye. and Bel'chenko, B„ V., "Sanitary Purification of Exhaust Gases (Removal of Nitrogen Oxides)/' Trudy Leningradskogo Tekhnologicheskogo Instituta im Lensoveta (SSSR), 36 , 133=8 (1956) 28 —>=.-, Kopylev, B A. and Petrova, N e A., "Absorption of Hydrogen Sulfide in Arsenate ^Carbonate Solutions in a Perforated Plate-type Absorber," Zh. Prikl. Khimii, 31, 8k9-$9 (1958) ,13. 29« Kafarov, V. V., "Modeling of Complex Processes/ 1 Zh. PrikjU Khimii, 28, 12&-7 (1955) — — 30 ■>-...«., and Dytnerskiy, Yu. I«, "Hydrodynamics and Mass Transfer in Packed Absorption Columns," Tr. Mogko- Khim - Tekhnal. In-ta im. D. I. Mendelcycva, 23 , l65*-7il U956) 31, =„„„ 3 "The Theoretical Analysis of Diffusion Processes, 85 Zh. Prikl. Khim&L, 29, UO-6, (1956) 32 »»i-«.^ "A New Method of Analysis, and Application of Similitude Principles to Diffusion Processes ," Dokl^ AN &SSR, 117 » 668-70 (1957) 33 m ~«, 9 m Calculations of Mass-Transfer Processes,™ Zhu Prikl. _Khimii, 31, 706-11 (1958) 3ii. e «.»«,«» ^ and Trofimov, V a I., "Analysis of Performance of Packed Towers Under Conditions of Free Turbulence, 8 ' Zb. Prikl Khimii ^ 30, 211^21 (1957) — 35. —— .-.^ and Trofimov, V„ I. "Analysis of Diffusions! Processes Under Developed Free Turbulence," Zh. Priklo Khimii, 31, 1809-16 (1958) 36 Kafarov, V V„ and Blyakham, L„ I 3 , "Absorption, Rectification and Heat or Mass Exchange," USSR Patent N 0o ICk, h99 (1957) 37 o Berman, L« D , "The Treatment of Experimental Data on the General Coefficients of Heat and Mass Transfer Between Liquid and a Gas (Vapor) Medium," Zh Priklo Khimii,, 29, No„ 1, 138-liil (Jan 1956) 38 -_~~ s "General Form of the Criterion Equations for Mass Exchange in Apparatus with Fixed Phase Interface," Zh. Prikl., Khimii,, 32, No» It, 807-812 (1959) ~~ 39 o Rozen, A. M„, "Analogy Between Counter-Current Isotope Exchange and Absorption Processes," Dokl AN SSSR, 108, No. 1, 122 (1956) llOo Ladyzhenskiy, R„ M , "Investigation of the Shape of a Gas Bubble Ascending in a Stationary Liquid,' 5 Zh 9 Priklo Khimii, 29, No 2, 217 (1956) "~ 111. Flit, I, Go, "Theory of Absorption Complicated by an Equilibrium Chemical Reaction in the Liquid Phase," Zh, Priklo Khimii, 31, No 1 5ii (1958) — ~ 1(2 o — — , "Absorption Processes in the Absorption of Carbon Dioxide by Potassium Carbonate Solutions ,« Zh. Prikl. Khimii, 31, 186-91 (1958) [1.3 =,„=„ ? and Shishkin, Ko N , "Absorption of Carbon Dioxide by a Bubble of Foam of Potassium Carbonate Solution," Zh. Pri_kl a Khimii, 29, 1323=29 (1956) -11- Uu Plit, I. G., "Regeneration of Absorbing Solutions in the Potassium Method of Removing Hydrogen Sulfide from Industrial Gases, H Zh c Prikl Khimii, 29, 16U4»7 (1956) ii^. — »-, "Kinetics of Regeneration of the Absorption Solution in the Potassium Method of Removing Hydrogen Sulfide from Industrial Gases 11/' Zh. Priklo Khimii s 30, 167-9 (1957) i}6„ Ramm, V M, and Zakgeym, A„ Yu., "Theory and Technique of Absorption," Khiiru Nauka i. Prom-sty, 3., 715 -2k (1958) Ij7„ Govorkov, V„ M. and Averbukh, Ya 8 D., "On the Methods of Calculating Mass Transfer in Apparatuses with Continuous Change of the Driving Force and in Apparatuses of the Step Type, 8 ' Zh. Prikl. Khimii , k s 800-07 (1959) ij8. Gasyuk, G. N« 5 Bol'shakov, Ao G„| Kortnev, Ao V and Krayniy, P. la., "Coefficients of Mass Transfer in Gaseous Phase Second Communication, n Zho Priklo Khimii, 1, 9$-99 (1959) ii9» Ganz, S. N« and Mamon, L„ I.., "Absorption of Nitric Oxide by Ferrous Sulfate Solutions," Zh. Prikl. Khimii , 26, 1005-13 (1953) 50* — -, and Kravchinskaya, So B., "Hate of Absorption of Nitrogen Oxides of Solutions of Ca (0H)« in a Revolving Absorber," 1 Zh. Priklo Khimii , 28, l?i5-55 (1955) 5l« Ganz, S, N.j Lokshin, M A„ and Kapturova, S I., "Kinetics of Nitric Formation in Rapidly Revolving Mechanical Absorbers. II. Coefficients of Absorption of Nitrogen Oxides fcy Nitric Acid in Mechanical Absorbers," Zh. Prikl. Khimii 9 28, 83I-J4O (1955) £2. —— s "Kinetics of Absorption on Nitrogen Oxides by Sulfuric Acid in a Rapidly Revolving Absorber, 18 Zh. Prikl. Khiinii, 29, 1018-28 (1956) 53 — - "», and Mamon, L. I., "Kinetics of Film Absorption of Nitric Oxide by Ferrous Sulfate/ Zh. Prikl. Khimii,, 30, 369-79 (1957) 5>iu Idem., n Kinetics of Absorption of Nitric Oxide by Solutions of Ferrous Sulfate in a Mechanical Absorber with a High Number of Revolutions," Zh._Prikl^ KMjTOii, 30, 553-6.1 (1957) 55>3 Ganz, S. N„, "Effect of the Hydrodynamic Condition on the Rate of Absorption of Nitrogen Oxides by Solutions of Calcium Hydroxide in a Mechanical Absorber on a Semiplant Scale, " Zh Prikl., Khimii, 30, 1311-20- (1957) 56. — — f 85 Generalized Principles of Absorption Processes in a Revolving Absorber, 58 Zh. Prikl.. Khimii 9 30, I60I4-II4 (1957) 57 o Fernovskaya, A. N. and B elopol"skiy, A„ P„ 3 "Absorption of Gases in Pressure of Surface -Active Agents. Mechanism and Rate of Absorption as Modified by Surface -Action Substances, 8 " gh. Fiz. Khimii , 26„ 1090 (1952) -15- 58 Fernovskaya, A. N and Belopol'skiy, A„ P #5 "Effect of Surface Active Substances on the Absorption Rat© of Carbon Dioxide and Ammonia in Water," ^^I^lJ^^Is 26 5 1097 (1952) 59o Sarukhanyan, T„ A„ and Belopol'skiy, A a P„ 3 ^Kinetics of the Absorption of Carbon Dioxide by Aqueous Ammonia Solution , w Zh» Prikl Khimii 9 27 , No 2, li|2 (19510 60 e Kuz'minykh, I, N ^ Aygina, Ye P» and Babushkina 5 M a D , " Absorption of Nitrogen Oxides by Soda and Lime Solutions ,"* Khinu Fro m--gt_^ g 8, 26-7 (1955) "~ 61 „ — —■ ^ and Bomshteyn, T,, B„ 9 "Kinetics of Hydrogen Sulfide Absorption by Ferric Hydroxide/ 5 J, A pp l Chem (USSR), 2J4, it97~50lt ( 195-1 ) 62 -«-»—., and Babushkina, M B , '"Equilibrium Between SOp and Magnesium Bisulfite Solutions/ Zh a Priklo Khimii^ 30, 1*66-69 (1957) 63„ -=. — s Aksel'rod, L„ S e § Koval% Zh A» and Rodionov, A, I„ 9 "Coefficients of Mass Transfer on Horizontal Perforated Plates at Varying Gas Velocities/* Khim i . Prom- st 8 ^ 2, 86-89 (19SU) Sk 9 -.-.—., Rodionov, A. I and Mishehenko, Yu a S , "Absorption of the Nitrogen Oxides in a Bubbling Column with a Varying Number of Plate s/ 1 Khimiya i Khim e Tekhnol a SokTo Perev a iz„ In a Period, Lit , 2, No« 2, WT09W) — - —_ - 65« Bukhman, A. S and Malin, K„ M s , a5 Effect of the Linear Velocity of Nitrogen Oxide Gases and Temperature on the Rate of Absorption by Sulfuric Acid/" Zh. Prikl. Khimii, 29 , N 0o k s 512 (1956) 66„ Malin, K« M and Bukhman, A. S„, "Basis for the Equation for the Calculation of Absorption Rates of Nitrogen Oxides in Sulfuric Acid/ 9 Zh, Prikl, Khimii, 29, 330-1; (1956) 6?. Bukhman, A S e and Malin, K. M., "Effect of Rate of Wetting on the Rate of Absorption of Nitrogen Oxides by Sulfuric Acid, 1 * Zh<> Priklo Khimii,, 2£ 9 No 3, 33ii-iil (1956) 68 a Idemo__ s "Driving Force of Nitrogen Oxide Absorption by Sulfuric Acid,' 8 Zh, Prikl, Khimii , 29, No a 6, 671-5 (1956) 69« Kuznetsov, M D„ and Sagalovskiy, A a Ye , "Kinetics of Hydrogen Sulfide Absorption by Ferric Hydroxide," Zh„ Priklo Khimii, 27, i„ 5 (195Ii ) - — 70 o =»=.=.^ Sagalovskiy, Sh a M and Popova, Ye V., "An Investigation of the Absorption of Ammonia from Coke-oven Gas with Sulphuric Acid in an Injection Type Apparatus," Koks i Khimiya, 2, 32 -3h (1959) -16- 71« Sirotkin, G. D, and Starostin, V. V., "Absorption of Nitric Oxide by Aqueous Solutions of Ferrous Salts ," Zh Prikl. Khimii , 27, lllil-li (19520 72 «.— * s "Absorption of Nitric Oxide by Aqueous Ammoniacal Solutions of Bivalent Cobalt Salts/ Zh. Neorgan Khimii, 1, 1750-7 (1956) 73. Timkin, N. I., "Disk Film. Absorbers," Khinio Prom-st ' , 308 (1957) 7h< Leybush, A. G. and Shneyerson, A. L., "Absorption of Hydrogen Sulfide and of its Mixtures with Carbon Dioxide by Ethanolamines," J« Appl Chem. (USSR) 9 23, No 2, lk$-$2 (1950) 75 • Mar 'ya sin, I, L», "Removal of Hydrogen Sulphide from Petroleum Refinery Effluents," Khim.. 1. Tekhol. Topliv i Hasel » 2, 3U-I4I (1958) 76 9 , Litvinenko, M. S c and Lundin, So P«, "Classification of Industrial Hydrogen Sulfi de-Absorbing Media By Thermodynamic Properties," Zho Prikl. Khimii, 29, 513-8 (1956) 77 8 Bagaturov, S„ A., "The Calculation of a Combined Absorption-Desorption Column in Gas Fractionating Plants ," Khimiya i Tekhnolo Topliv i Maacl, No. 5* 2lt-33 (1958) 78 Ponomarev, G. V., "Calculating Absorption and Desorption Processes in Gas-Gasoline Plants," Khimiya i Tekhn olo Topliv i-Mascl , 2, ll*»21 (1958) 79© Gal'koyskiy, V„ B.j Mel'nikov 5 Yu„ I« and Vetrova, A. V., "Chemisorption in Bubble Towers," Zh, Prikl Khimii,, 30, 1760-3 (1957) 80® Shvartsshteyn, Ya, V , "Recovery of Nitrogen Oxides with Sulfuric Acid in a Tower with Plane -Parallel Packing," Khim. Prom-st", 1956 a No<, 5 5 8-11 1 Ref a Zh 9 Khjjtiiya, No, 9 5 1957 17- ADSORPTION Adsorption — the process by which a solid surface attracts and holds molecules or ions from a gaseous or liquid phase in contact with the solid — was first discovered and reported late in the 18th century. However,, it remained a laboratory curiosity until the early 19Q0«s, when systematic study of adsorption phenomena developed as part of the general growth of physical chemistry,, Early pioneers in this area were Jo W. McBain in England, H, Freundlich and M. Polanyi in Germany, and Irving Langmuir and Hugh S, Taylor in the United States, Since 1930, significant con- tributions have been made by Paul H, Emmett, Stephen Brunauer, Edward Teller and Henry Eyring working in the United States and by A. A, Balandin, Mo M. Dubinin and A. V, Kiselev in the Soviet Union, Brunauer presents an excellent historical development of theory and early research in adsorption, l/ In recent years, adsorption has achieved industrial impor- tance in gas and liquid purification and factionation processes, and as a vital intermediate step in heterogeneous catalysis Adsorption is a very popular subject of research in the Soviet Union, and several institutions of higher learning maintain adsorption laboratories e 2/ USSR scientists are not only abreast of the latest developments in this field, but several of their number have achieved international prominence. Their best work is of excellent quality, and they are adept at applying mathematical analysis and the latest experimental techniques to fundamental studies of adsorption. However, many Soviet papers in adsorption are in the category of data collection, with considerable repetition of subject matter and painstaking pursuit of detailed behavior of various adsorbents and adsorption systems. Theoretical papers are often cryptic and many times offer only a minimum of supporting data. Study of gaseous systems is emphasized, with relatively little work on adsorption from liquids. Further, there is little orientation toward the design and development of industrial processes or equipment, so that the Soviet effort in adsorption is more properly described as physical chemistry rather than chemical engi- neering. Recent and current Soviet work in adsorption will be discussed under six subject headings § (a) studies of adsorbents, (b) adsorption equilibria and rates, (c) adsorption in catalysis, (d) chemi sorption, (e) experimental techniques, and (f) industrial applicationso Studies of Adsorbents Several Soviet investigators have made systematic studies of adsor- bent structure and its relation to adsorptive properties. Typical of this work is the research on silica gels under the general direction of A, V, Kiselev at Moscow State University and the studies of activated carbons by M, Mo Dubinin and associates at the Institute of Physical Chemistry, Academy of Sciences, in Moscow,, Other Soviet investigators who have con- tributed significant research in this general area are I, Ye, Neymark at the Institute of Physical Chemistry im, L, V, Pisarzhevskiy, Academy of Sciences Ukrainian SSR, who has studied silica gels and various modified -18- silicates^ S. P. Zhdanov at the Institute of Silicate Chemistry in Leningrad,, a specialist on porous glasses^ and V. T. Bykov at the Far Eastern Affiliate im. V, L« Komarov s Academy of Sciences^ who has investigated several natural adsorb- ents o » Ao V. KiseleVj a very prolific writer s has averaged over 10 publications on adsorption annually since 1950° Most of his papers list co-authors^ pre- sumably colleagues and students <> He also writes extensively on other aspects of physical chemistry 5 notably kinetics and catalysis « A leading exponent of the "adsorptive-structural method"' of studying adsorbents^ Kiselev set forth his basic approach to this problem in a fundamental paper published in 19k? ° 3/ In this work he classifies adsorbents into four structural types 9 based on their specific surface^, pore volume^ and pore size distribution,, which he sup- ports with representative isotherm data. Kiselev and his students have center- ed their attention on silica gelSc, and they have published numerous articles relating gel structure to adsorption properties . h/ 11-13/ These papers tend to be somewhat repetitious and to review earlier work,, but most of them report at least some new significant data. As this work progressed., Kiselev recognized the significance of chemical as well as physical properties of adsorbents o 1U-18/ His current experimental research deals with the effects of gel hydration on adsorptive properties,, particularly toward water s alcohols^ and other compounds capable of forming hydrogen bonds. 17 / 18/ 18 a/ 19-21/" In addition to silica gel s he is also studying the structure of aluminum silicate catalysts,, activated carbons p and magnesium hydroxide. 22-29/ Kiselev works primarily with gas adsorption,, but he has also investigated the influence of adsorbent structure on adsorption from solutions by both silica gel and activated carbon,, 3.0-3 5/ In a recent paper Kiselev described a series of experiments in the modification of adsorb- ent surface structure by means of chemical reactions,, 36/ He found that reac- tion with alkylchlorosilanes removes surface hydroxy! groups and renders sili- ca gel hydrophobic o Oxidation of activated carbon by treatment with NaC£p2 forms surface carboxylic and phenolic groups which greatly enhance its affin- ity for water and other polar adsorbates. Kiselev' s early approach to the problem of adsorbent structure was large- ly experimental and empirical,, and he inferred structural configurations from measurements of adsorption-desorption isotherms and heat effects. Later papers report confirming structural data obtained from X-Ray and electron- microscope measurements. Currently he is studying adsorbent structure theo- retically as well as experimentally 5 suggesting methods for calculating and predicting adsorption forces from structural characteristics. 37—UO/ This development parallels the general evolution of adsorbent studies in other countries^, but Kiselev has been somewhat slow in introducing theoretical justification of experimental results. M. M. Dubinin is probably the Soviet specialist in this area who is best known abroad. He has published widely on various aspects of adsorption* but his chief work has been a continuing investigation of activated carbons. Some of his studies have been largely experimental s consisting of the collec- tion of extensive equilibrium data with numerous adsorbates and empirical correlation of these data by means of various existing isotherm equations. U1-U7/ However,, Dubinin recognized the importance of theory even in his early -19- work, and his more significant papers stress the application of basic fund- amentals and mathematics to the elucidation of adsorbent structure and adsorp- tion phenomena,, Based on the Polanyi theory of adsorption potential l/ I48/ Dubinin developed new isotherm equations, suggesting that adsorbent as well as adsorbate properties must be taken into account* l#-52/ He classified active carbon porosity into three types, according to size and adsorption characteristics,, 53-55/ In '"micropores* 8 (diameter substantially less than 50 microns) he found adsorption to be proportional exponentially to (log pres- sure), 2/ while in "macropores 1 " (1000 microns and larger) only to log pres- sure,, Adsorption in intermediate pores follows an intermediate relationship* These findings are well summarized in a series of very similar papers pub- lished both in the USSR and abroad* £6-60/ Dubinin has also made an extensive study of carbon surface oxides and their effects on adsorption of various vapors * 61-68/ Capacity for adsorb- ing non-polar gases was found essentially independent of surface oxidation, whereas surface oxides greatly increased the adsorption of water vapor and other polar substances., Dubinin reasoned that oxides serve as active cen- ters capable of forming hydrogen bonds and creating '"islands" of a two- dimensional condensed phase which eventually coalesce into a monolayer cov- ering the whole surface* He substantiated this theory with measured heat effects closely approximating heats of liquid condensation., By postulat- ing a definite surface mechanism, Dubinin takes issue with the "American School* 1 , which attributes isotherm discontinuities to capillary condensa- tion,, He acknowledges, however, that the problem is not completely solved and proposes further study via other chemical treatment of carbon surfaces and microwave spectroscopy of bonds* 68/ Lately Dubinin has returned his attention to the more general problem of carbon porosity* He is studying more rigorous mathematical methods of calculating pore volume distribution, 6g^-7l/ including statistics* 72/ He is reanalyzing data obtained earlier in an attempt to develop more pre- cise isotherm equations and to correlate both adsorbent and adsorbate prop- erties* 73°- 75/ Recently he introduced the concept of branched porous struc- tures, suggesting a more sophisticated approach than evidenced in some of his earlier papers* 76/ As this work progresses, it should further enhance Dubinin's established international stature as an expert on adsorbent struc- ture* The work by I* Ye, Neymark on adsorbent structure started with studies of silica gel porosity in relation to benzene and methyl alcohol adsorption characteristics* In 19U7 he reported that the pore volume of silica gel was increased by raising the surface tension of the acid coagulant used in precipitating the gel* 77/ He classified gels into three types* (micro- porous, medium, and coarse) and showed that adsorption hysteresis and capil- lary condensation increase with pore size* 78/ 79/ He suggested that on microporous gels benzene adsorbs as a vapor, but on coarse gels as a con- densed liquid* 80/ Neymark found that silica gel porosity could be affect- ed by the purity of wash water used in its preparation^ gels washed with distilled water had finer pores than those washed with tap water containing calcium bicarbonate, which partly transformed the surface to calcium sili- cate* 81/ 82/ Results such as these led him to experiments in modifying the surface of silica gel with hydrophobic ions 83-85/ and to the preparation -20- and study of various gel mi&tures and complex silicates., 86-91/ By co-precipitating alumina and silica, Neymark has been able to make gels with porosities intermediate between pure silica and alumina gels, 86— 8?/ A new family of gels was prepared by adding titanium oxides to sodium silicate solutions^ followed by precipitation with sulfuric acido 88-89/ Recently Neymark and co-workers found that the adsorption activity of alumina gels decreased with "ripening" in the mother liquorj this effect is parallel- ed by transformation from the amorphous to the crystalline state, as confirm- ed by X-ray analysis© 90/ Neymark' s latest work concerns the preparation and characterization of ferrogels of varying porosities 91/ and of silica gels modified with nickel, magnesium and titanium hydroxides 5 in which he reports that alcohol treatment during preparation and drying increases gel porosityo 92/ For several years, So P. Zhdanov has been studying the structure of "porous glasses' 8 made by treating crushed glass or quartz with strong alkali solutionso His methods involve adsorption measurements, crystallography, and electron microscopy,, 93-95/ 101-102/ Recently Zhdanov has been concern- ed primarily with surface hydration and its relation to chemical structure, 96^100/ His results and their interpretation are in general agreement with the work of Kiselev, as pointed out in a recent joint paper. 98/ Zhdanov postulates that surface hydroxyl groups are largely responsible for the ad- sorptive properties of porous glasses 99/ and that every adsorbed water molecule must be "connected with" two hydroxyl groups . 100/ Thus dehydra=? tion of a silicate adsorbent affects the nature as well as the extent of its active surf ace So A. Levina and II. F. Termolenko at the Institute of Chemistry, Aca- demy of Sciences Belorussian SSR, have been studying the structure and ad- sorptive properties of various gels in relation to precipitation conditions and drying methods used in their preparation. They are concerned primar- ily with aluminum a chromium and iron hydroxides, 103-106/ although a paper on cadmium hydroxide has also appeared. 107/ In collaboration with Z„ A. Krivchik, Yermolenko has also investigated the steam activation and heat treatment of various commercial charcoal adsorbents. 108/ Vo A. Kargin at Moscow State University, a leading Soviet specialist in polymer research, has used adsorption as a means of identifying polymer structure. For example, he has distinguished between dimer and crystalline polyamide by means of formic acid adsorption. 109/ From data on adsorption of hydro gen at ed monomers on a variety of amorphous vinyl and acrylic resins. Kargin has studied changes in molecular packing density in vitreous-elas- tic transitions. 110/ He has compared synthetic and natural rubber struc- tures by means of hexane adsorption. Ill/ A summary of Kargin' s findings concerning polymer structure and adsorption characteristics was published abroad in 195?« 112/ A number of Soviet adsorption specialists have been cataloging the properties and structure of natural adsorbents native to their country. Typical of this effort is the work of V» To Bykov, who has studied sys- tematically various diatomites, clays and weathered earths from differ- ent areas of the Soviet Union. 113-116/ Adapting some of Dubinin's techniques and isotherm equations, Bykov has studied porosity by capillary condensation and mercury pressure methods 117-118/ and developed a dynamic procedure for measuring adsorption curves, whereby a standardized organic solution is passed through a column of adsorbent and the effluent is anal- yzed in small increments,, 119-120/ Other recent Soviet investigations of natural adsorbents include studies of several Georgian clays of the ben- tonite series by G„ V n Tsitsishvilij 121,/ of dark green Odessa earths by So I. Burshteyn and associates! 122/ of Chenushy bentonite clay by V. Bregvadzej 123/ of Volga diatomites by F„ A» Slisarenko and co-workers; 12U/ and of several kaoline and montmorillonite clays by M, I„ Kuadzhe<» HI/ )tion Equilibria and Rates Several Soviet investigators have contributed significant information to the literature on adsorption equilibria and rates,, often as a by-product of other work. For example, M. M» Dubinin's continuing research on acti- vated carbons has brought him international recognition as a leading ex- ponent of the potential theory of adsorption and an expert on adsorption isotherms of -various materials on carbon surfaceso U6-U7/ h9/ 50-52/ 5?/ 6l/ 65/ 66/ 71/ 75/ Similarly, Ao V„ Kiselev has made extensive use of isotherm measurements in his studies of adsorbent structure and consequent- ly published data on adsorption equilibria of nitrogen, water vapor and various organic materials, 5/ 9/ 11-13/ U/ 19-21/ 23-25/ 28/ 32-3U/ Kiselev has also participated in detailed analysis of low-temperature nitrogen isotherms on various adsorbents, 126/ 127/ and in the development of an ultrasensitive automatic calorimeter for measuring heats of adsorp- tion. 128/ With the aid of this device,, Kiselev and A. Ao Isirikyan have been making a continuing investigation of heat effects in the adsorption of various hydrocarbonso 129-133/ Based on the heat effects involved, they picture physical adsorption as a three-step process | first a revers- ible adsorptive process until the pressue is reached where desorption hysteresis begins, then a region of capillary condensation with hystere- sis, and finally an area of reversible capillary condensation 129/ They also suggest that heat of adsorption for normal alkanes varies line- arly with the number of carbon atoms per molecule,, 133/ No No Avgul' has appeared as the principal author in a series of sig- nificant joint papers with Kiselev and other colleagues at Moscow State University dealing with the adsorption thermochemistry,, By measuring dif- ferential heats of adsorption of hydrocarbons, water, and alcohols on car- bon black, Avgul 1 , 0, M. Dzhigit and Kiselev conclude that on porous car- bons, hysteresis and capillary condensation are involved, whereas on non- porous carbon, unimolecular adsorption via hydrogen bonding predominates 13U-138/ On silica gel, they found that the capillary condensation theory and differential heat measurements enable simple calculation of surface areas that agree closely with more conventional area determination methodso 139/ In collaboration with several others, Avgul 1 and Kiselev have extend- ed their calorimetric studies of adsorption to support more general consi- derations of thermodynamics and adsorption forces on active carbon sur- faces. Experimental data are reported in close agreement with calculated -22= values of free energy and entropy of adsorption for benzene^, lUC/ nitrogen,, and ammonia^, lip./ a series of normal and branched alkenes p lIplUU/ and various non-polar molecules., 1)45/ Influence of chemical structure and po- rosity of the carbon surface was also studied, ll|6/ 2Mj/ The most recent paper by these authors concludes from entropy curves that isoalkanes and naphthenes are adsorbed on carbon black in a dense layer closer to the liquid state than adsorbed normal alkanesj an additive scheme is proposed for calculating heat and free energy of adsorption of branched hydrocarbons, lij-8/ This work appears to be of excellent quality and demonstrates that Kiselev 5 Avgul" and their colleagues at Moscow State University are well versed in both the theory and practice of modern adsorption thermodynamics „ Two other highly competent Soviet specialists in this area are Bo P, Bering and V„ V« Serpinskiy of Dubinin's staff at the Academy of Sciences" Physical Chemistry Institute in Moscow Several years ago they developed an equation of state for adsorbed molecules in a monomolecular layer,, IhS/ More recently they have derived simple equations for heat and entropy of adsorption^ respectively? where u is the Polanyi adsorption potential (* " RlJ^tn);, a is the quanti- ty adsorbed,, ©(, is the volumetric coefficient of expansion of adsorbate and h is the pressure ratio (:=. 1P/j>s4X ) • These equations are claimed to agree closely with calorimetric data from the literature and to permit calcula- tion of differential heats of adsorption from a single isotherm curve,, 150/ Bering and Serpinskiy have also collaborated on some interesting ex- perimental studies. They developed a quartz microbalance of high sensi- tive ty 5 which enable precise isotherm measurements at low pressures* 152/ 153/ They investigated carbon dioxide adsorption on silica gel at pres- sures up to 85 atmospheres and found evidence of a liquid-state adsorbate at termperatures below the critical « 15V They also published a series of papers on. the adsorption of gas mixtures*, but appear to have concluded this experimental study without offering any confirmed general theory of such systems o 155-160/ In collaboration with K» A„ Ioyleva^, Bering published three interesting experimental papers on the adsorption of water and various organic vapors on mercury surfaces „ 161-163/ They suggest that isotherm discontinuities result from two -dimensional phase transitions (surface con- densation) and report that differential heat of adsorption attains a maxi- mum close to complete coverage of the surface Typical of a number of recent Soviet experimental studies reporting gas adsorption isotherms for various systems,, are papers on the adsorp- tion of various organic vapors on mica a I6I4/ and of hydrocarbons on char- coal 165/ and on commercial aluminum oxide,, 166/ Mo G„ Kaganer has studi- ed nitrogen adsorption isotherms at very low pressures down to the region where Henry's law applies,, l6j/ Bo V Il 8 in has proposed some semi-quan- -23- titative rules concerning molecular attraction in adsorption from data on the foisat ofiwetifngr'of various" adsorbent surfaces/ 168/ '»L» ?» Radushkevich ismg seeking to explaim capillary condensation phenomena with tEe^ aid "of calcula- tions on various proposed physical models « 169-172/ Several Soviet workers have been studying adsorption kinetics • Among the principal efforts are those of D. P„ Timofeyev and Ya„ M« Bikson at the Institute of Physical Chemistry, Academy of Sciences,, in Moscow,, Timofeyev has studies both adsorption and desorption rates of benzene vapor in thin layers of activated carbon,, He has found that adsorption kinetics may be controlled by either external or internal diffusion „ 173$llk/ However, de- sorption rates are generally much slower and controlled by pore diffusion,, 175/ By means of X-ray techniques, he is seeking to distinguish between diffusion in the volume of the pores, and on their surface,, 176/ Timofeyev has suggested a dimensionless ratio /D (where d = particle diameter , v = velocity of air-vapor mixture, D - internal diffusion coefficient) as a criterion for predicting diffusion mechanism in adsorption from an air- vapor mixture flowing through a thin bed of adsorbento He states that ex- ternal diffusion controls when ®&/d<% and internal diffusion controls when ^ V /D^ 20 o According to Timofeyev, for values between $ and 1$ 9 the adsorption front inside a spherical particle progresses at approximately constant rate almost to complete saturation,, 177/ Bikson has treated math- ematically the problem of adsorption dynamics for a binary gas mixture in an adsorbent column, suggesting equations for calculating the length of the working layer under conditions of parallel transfer,, 178? 179/ It seems strange that this basically sound work has not been followed up with subsequent papers,, Mo V. Tovbin and various co-authors have studies desorption rates from activated carbon into solutions in relation to porosity 5 grain size and elution rate Some of this work involves iodine and uses radioactive tracer methods „ 180-182/ Tovbin has suggested a self-adsorption mechan- ism to account for enhanced retention of adsorbate at concave surfaces in capillaries. 183 3 18U/ He is currently studying the desorption kinetics of acetic acid and other polar organic compounds o 185/ Other recent Soviet studies in this area worthy of note are the of N. Do Gorchakov and I. I, Pogodin on the rates of stripping various organic solvents from charcoal columns with carbon dioxide gasj 186/ and research on internal diffusion coefficients in porous catalysts by Ko N« Bolonogov and Bo L Popov 18?/ K, A„ Gol'bert has suggested a method for calculating sorption dynamics for the case where the limiting step is internal diffusion 188/ Later he applied this approach to the analysis of data on the adsorption of ethylene from binary mixtures with hydrogen, methane and nitrogen, 189/ Interest in developing calculation methods applicable to commercial process design seems to be rather limited in the Soviet literature « P» le. Romankov has suggested equations applicable to adsorption and desorption of gases in fluidized beds of adsorbent© 190$ 191/ Ao N, Planovskiy and L. A. Vlasenkov studies the separation of methane-hydrogen mixtures in a five- stage fluidized char apparatus « They reported that at high saturation levels (0.9 and above) adsorption is controlled by internal diffusion and -2U- at lower levels (below 0„8) by surface diffusion » 192/ No I. Smirnov and co-authors have derived differential equations describing steady-state ad- sorption in packed towers^ 19 3 * Wh/ and extended these to a simplified method for correlating mass transfer coefficients with gas concentration, gas velocity and height of sorbent layer 195/ Ya V„ Shevelev has offer- ed a general solution for dynamic adsorption in packed beds^, but restricted to linear isotherms,, 196/ Ye. V Vagin and Ao Ao Zhukovitskiy recently pub- lished a mathematical paper working out distribution equations for thermo- adsorption separation processes^ but again on the basis of linear isotherm behavior o 197/ Although Soviet research in adsorption is concerned largely with gas- eous systems, some interest in adsorption from liquids was also notedo Several of these papers appear aimed at processes for recovering and sep-= arating metals . For example, lo V„ Gebler and K. K. Stramkovskaya report- ed that copper, silver, and gold are adsorbed from their aqueous solutions by granulated brown coal. 198/ X. Ye. Starik and I Ao SkiiUgskiy have studies the adsorption of radioactive elements from dilute nitrate solu- tions on fluoroplast and paraffin surfaces. 199/ S e A„ Voznesenskiy and colleagues report that the addition of ethyl alcohol or acetone markedly increases the adsorption of microquantities of Cg ^ l and S r "9 from water solution on ultramarine, iron oxide, barium sulfate, and titanium dioxide adsorbents. 200/ I. Ao Sheka and B, A» Voytovich have devised a method for separating zirconium and hafnium by silica-gel adsorption from solu- tions of their tetrachlorides in methyl alcohol o 201/ M S. Belen'skiy and T. G« Alkhazov investigated the kinetics of silver salt adsorption by activated carbon. 202/ D, No Strazhesko and collaborators have found that the adsorption of strong acids and electrolytes by carbon from non-aqueous solutions is electrochemical in nature 203-207/ N. Ao Izmaylov has reviewed the theory and practice of adsorptionai separations o 208/ I. P. Kutanov has correlated the effects of functional groups on the adsorption of various organic acids from alcohol and acetone solutions on activated carbon. 2 09-211 / Ao N. Kharin has studied kinetics of iodine, 212/ essential oil 2lj/"and acetic and butyric acid adsorption from aqueous solutions on activated charcoalo 21V Analytical separations of aliphatic alcohols by means of silica gel 21^7 and of normal hydrocar- bons via adsorption on carbamide 216/ have been suggested. I.* V. Smirnova and K V. Topchiyeva are studying the adsorption and molecular orientation of various hydrocarbons on alumina and other catalyst materials. 217a 21 S/ The role of adsorption phenomena in electrochemical kinetics has been reviewed by A» N. Frumkin. 219/ Some recent Soviet papers in this area include a theoretical and qualitative experimental study of adsorption iayezs on falling drops of electrolyte by S„ S. Dukhin and B. V, Deryaginj 220/ investigation of cation adsorption at platinum electrodes by A. D. Obruchyevai 2 21 ,_ 22 2/ and studies of anion adsorption by N. A. Balashova 223/ and So Ao Nikolayeva and S„ Rakhnuo 22V' B e So Krasnikov and M c V. Pevnitskaya discuss recent Soviet research on the adsorption of surface- active agents at platinum and copper electrodes. 225/ Vo L, Kheyfets and colleagues at the Ao A« Zhdanov State University in Leningrad have published a series of papers on experimental studies of the effects of various adsorbed materials on double-layer phenomena at solid metal and -25- mercury electrodes, 226-230/ Adsorption in Catalysis Detailed analysis of Soviet research on catalysis is beyond the intend- ed scope of this report,, However, several Soviet catalysis specialists have studied the role of adsorption phenomena in catalytic mechanisms, and brief discussion of some of their recent work is appropriate here,, Probably the best-known Soviet expert in this area is A„ Ao Balandin of Moscow State University., Based upon extensive theoretical and experi- mental evaluations of activation energies and adsorption forces, Balandin formulated his multiplet theory of surface layers, postulating superimposi- tion of an adsorbed molecule on the lattice of the catalysto 231-235/ He then suggested rules for relating activation energy effects and layer changes and explaining catalyst selectivity on the basis of chemical properties and adsorption bond energies© 236-238/ Balandin' s theories are well summarised in a recent review of his own work. 239/ To facilitate their practical ap- plication, he has developed a method for precise determination of relative adsorption coefficients and used it to measure the free energy of adsorptive displacement of butylene by water on catalyst surfaces. 2l;0, 2l|l/ He has interpreted kinetic data on catalytic hydro genation, dehydrogenation and dehydration reactions in terms of adsorption and surface orientation effects. 2l+2-2l|[i./ A recent study by Balandin and colleagues of the relative adsorp- tion of various saturated alcohols on oxidizing catalysts concludes that both plane-orientation and normal-orientation exist and suggests a new term "specific effective place" to describe a surface site capable of accomodat- ing a particular molecule. 2li5/ So Zo Roginskiy published a book in 19U9 on adsorption and catalysis on heterogeneous surfaces. 2)4.6/ He has suggested that the catalytic prop- erties of heterogeneous surfaces can be predicted from data on heats of oxygen and hydrogen adsorption. 2kl/ Later Roginskiy and co-workers showed that metal oxide catalysts which strongly adsorb phenol, promote alcohol dehydrogenation, whereas those which adsorbe pyridine readily promote de- hydration. 2U8/ Another paper suggests use of molecular adsorption to evaluate the effect of catalyst additive,, 2I4.9/ Recently, Roginskiy has been using exchange reactions of adsorbed isotopes to study intermediate compounds on catalyst surfaces. 2,5>0/ A colleague of his at the Moscow Institute of Physical Chemistry, Academy of Sciences, N B V. Kavtaradze, is studying hydrogen adsorption heat effects as a means of predicting catalytic activity of nickel, platinum, iron and chromium toward hydro- gen ation reactions. 251-252/ Another advocate of adsorption as a tool in catalysis research is A. Mo Rubinshteyn of the Institute of Organic Chemistry imeni N» D. Zelinskiy,, Academy of Sciences, USSR. He has perfected a dynamic method for measuring catalyst areas by benzene adsorption and uses adsorption measurements to study and correlate the activity of various types of cat- alysts. 253-256/ A. Io Shlygin of Moscow State University has studied gas adsorption effects on the catalytic activity of platinum electrodes 257-261/ -26- Studies such as these, while not greatly different from contemporary research outside of the Soviet Union^, are significant because they show that Soviet physical chemists are capable of applying their extensive knowledge of adsorption phenomena to support their research on catalysis Chemi sorption The leading Soviet specialist in chemisorption is Fo F. Vol " kenshteyn at the Moscow Institute of Physical Chemistry 5 Academy of Sciences « He has made several significant contributions to knowledge in this area, starting with his fundamental theory of activated adsorption set forth in a series of papers published in l°5>2~»5>3o 262-266/ His basic assumption is that free electrons in the adsorbent lattice act as adsorption centers j he shows that the number of these centers per unit surface increases with increasing tem- perature and increasing coverage. This leads to a mathematical expression for adsorption equilibria approximating the Freundlich isotherm, provided that interaction between adsorbed molecules and their dissociation are ab- sent* Vol 'kenshteyn postulated that surface impurities^ as well as lights can influence the concentration of adsorption centers^ and he conceived of both "donor" and "acceptor 5 * impurities acting in opposite directionso Later he suggested that both "weak 1 " (one-electron) and "strong" (two-elec- tron) bonds may exist j "strengthening" is accomplished by the capture of a free lattice electron by the adsorbed atom and may absorb or evolve heat, depending upon whether or not a Whole 1 * is created in the adsorbent lattice £67/ Subsequent papers refined this theory to allow for surface inhomo- geneity and dissociation of diatomic molecules 268^ 269/ It was extended to provide a theory for the action of semi-conductor catalysts by assuming that only atoms or radicals adsorbed in the "weak" state and displaying un- saturaged valences possess enhanced reactivity© 270-273/ Recent experi- mental data on benzene oxidation appear to confirm Vol "Kenshteyn "s theories quite well. 2]h/ Vo Lo Bonch-Bruyevich and V<> B» Glasko are seeking to develop general- ized equations for chemisorption on various types of metals, with the aid of a "Strela" computer c 275 / Recently Sh M„ Kogan proposed a statistical method to calculate the distribution of "weak", "strong" and "strong donor" bonds^ to further extend the Vol "kenshteyn theory 276/ For several years, V. I*» Lyashenko and co-workers at the Kiev Institute for Physics, Ukrainian Academy of Sciences,, have been studying chemisorption experimentally,, Early experiments showed that the adsorption of polar mole- cules altered the conductivity and work function of copper, zinc and cadmium oxide semiconductors, whereas non-polar molecules had negligible effecto 277/ Similar effects were later observed on molybdenum sulfide • 278/ Ad- sorbed molecules were also found to alter the photoconductivity of various materials. 279-281/ In a subsequent study,, Lyashenko found that the work functions of CuQ, NiO, Mn02 and germanium exhibited maximum values when acting as catalysts for GO oxidation or N2O decomposition 282/ Lyashenko and Vo Go Litovchenko are currently studying the influence of various polar and non-polar adsorbates on the work function and conductivity of germanium - as well as on the rates of the changes involved,, 283/ 28U/ Another interesting line of study is suggested in a recent paper by „27- Ao Terenin and Yu, Solonitzin, 285/ They have investigated the action of light on chemisorption and report highly specific effects o Oxygen is strong- ly photosorbed by silica gel and by ZnQ in presence of excess oxygen, but it is photodesorbed from ZnO with zinc in excess , Earlier P Ye Val'nov reported that CO is photodesorbed from nickel and H2O from cadium and zinc, but not from bismuth or antimony, 286/ Experimental Techniques Soviet researchers in adsorption appear to be thoroughly conversant with the latest experimental techniques in their field,., Their papers frequently mention methods and equipment described in the Western liter- ature and often suggest improvements and refinements. They are adept at using modern instruments, such as the electron microscope, x-ray devices and spectrophotometers, to corroborate evidence inferred from adsorption measurements as to adsorbent and adsorbate properties. Recent literature indicates increasing use of radioactive tracer materials. In short, So- viet scientists appear to be competent and resourceful experimentalists. These conclusions are confirmed readily by the descriptions of apparatus and methods in the experimental studies cited above. In addition, a few more examples will be mentioned,, A. I, Sarakhov has developed a micro -torsion balance with a sensi- tivity of approximately 5> ^c 10™° gram, 28?/ Using this device he has been able to study adsorption on relatively non-porous materials with specific surface less than 1 square meter per gram, 288/ 289/ Sarakhov has collaborated with M, Mo Dubinin in developing a simple low-pressure device for measuing adsorbent porosity by means of mercury,, 290/ Rubinshteyn has perfected simplified dynamic methods for measuring catalyst surface areas with physically adsorbed benzene vapor 253/ 291/ 292/ or chemisorbed iodine from CC^_^ solution, 293/ He has also design- ed a microtome for preparing catalyst sections down to 0,01 micron in thickness for electron-microscope examination,, 29U/ M, G Kaganer advo- cates use of very low pressures in area measurements by the BET method, 295/ and D« P, Dobychin suggests a scheme whereby only one point is nec- essary in using the BET equation, 296/ B, N, Vasil'yev has designed an adsorption apparatus capable of attaining and operating at 80 atmospheres pressure without using a compressor, 297/ A, N, Frumkin discusses the application of electrochemical techniques in studying surface phenomena, 298/ L, N, Kurbatov reviews the dielectric properties of adsorbates on silica gels 299 / S, Yu, Yelovich and L, Ya, Margolis describe an experimental method for measuring surface conductivity of adsorbents, 300/ I, V, Zhilenkov suggests using the Debye dispersion effect to study water adsorption on silica gel, 301/ Several analytical methods based on adsorption are mentioned in re- cent Soviet literature. Development of gas chromatography in the Soviet Union is credited largely to A, Ao Zhukhovitskiyj, presently occupying the chair of Physical Chemistry at the Moscow Steel Institute, 302/ He has -28= worked out the theory of thermo-adsorption separations 303/ and recently pat- ented a laboratory apparatus for continuous separation of gases • 30ij/ A. M. Brodskiy and colleagues have described an apparatus capable of semi -quantita- tive separation of a 12-component mix-cure 305/ and described its testing with radioactive tracersc 306/ P. No Fedoseyev has suggested alkaline-earth sili- cates as adsorbents for SG>2 i n combustion analysis of organic substances a 307/ Industrial Applications The application of adsorption techniques to large scale fractionation of gases and liquids is poorly developed in the Soviet Union, Recent literature shows increasing Soviet interest in this area, but the USSR appears to be con- siderably less advanced than the Western world in both processes and equipment „ Use of activated carbon for the purification of gases has been practiced in various Soviet industries for a number of years • 308/ Improvements in oxy- gen production have been achieved by adsorptive drying of air with alumina,, 309-311/ and by removing acetylene and carbon dioxide via low temperature ad- sorption on silica gel c 312/ 313/ Recently a new process was patented for re- covering and concentrating krypton and xenon in oxygen plants through silica gel adsorption. 3lU/ Continuous moving-bed adsorption processes are relatively new to Soviet industry* As recently as 1958, there were none in operation, 315/ but there are at least some process developments in the laboratory stage, N. V« Kel'tsev has described an experimental moving-bed apparatus for drying gases 316/ and another for separating acetylene-carbon dioxide mixtures. 317/ Kel'tsev and two colleagues have patented a process for continuous adsorptive fractionation of butane-butyl ene mixtures with silica gel. 318/ A recent arti- cle by P. Benedek and co-workers describes an experimental hypersorber for sep- arating mixtures of hydrogen, CO, C02* and acetylene, but admits that it copies the Berg process (American). 319/ Some originality is shown by L. A. Kul'skiy and colte agues in their design of two-stage countercurrent adsorber for recover* ing phenol from water solution. 320/ •29- G. REFERENCES — ADSORPTION 1. Brunauer, Stephen, The Adsorption of Gases and Vapors , Princeton University- Press, 19U5 2. Kiselev, A. V., "Research on Adsorption by the Chemical Faculty of Moscow State University," Uch. Zap. MGU , No. 7k, 229-3U (1955) 3. , "Basic Structural Types of Adsorbents and Their Effect on the Adsorption Properties," Zh. Fiz. Khimii , 23, Mo. k, U52-U68 (19k9) U. — , and Kamakin, N. M. , "Absolute Adsorption Isotherms of Vapors on Silica and Alumina-Silica Gels of Different Structures," Dokl. AN SSSR , 80, 393-96 (195i; 5. Dreving, V. P.j Kiselev, A. \/. and El'tekov, Yu. A., "Dependence of the Adsorp- tion of Isopentane Vapor on the Pore Dimensions of Silica Gels," lokl. AN SSSR , 86, 3U9-52 (1952) 6. Kiselev, A. V., "Structure of Silica Gels and Its Affect on Adsorption Prop- erties," Issledovaniya v Oblasti Khromatografii, Trudy Vsesoyuznogo Soveshchaniya Khromatografii, Akademiya Nauk SSSR, Otdelenie Khimicheskikh "auk, 1950, 71-97 (1952J " 7 o „_. — 9 "Specific Surface Area of Adsorbents of Various Structure, Absolute Isotherms and Heats of Adsorption," Metody Issledovaniya Struktury Vysokodisper* snykh i Poristykh Tel, AN SSSR, Tr. Soveshchaniya , 1951 , 86-113 (1953) 8. 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N., "The Effect of Dehydration of a Silica-Gel Surface on Its Adsorption Properties," Dokl. an sssr , $>k, 85-8 (195k) 15. Kiselev, A. V., "Effect of the Size of Pores and of the Chemical Nature of the Surface of Silica Gels on Their Adsorption Properties," Tr. Komis. po Analit. Khimii. AN SSSR , 6, U6- 76 (1955) =30- 16. Kiselev, A. V. , "Acidic-Basic Mechanism of the Adsorption on Silica Gel," Dokl. AH SSSR , 106, 10U6-U9 (1956) 17 o ..-__- 9 and Khrapova, Ye. V., "Influence of Pore Size and Surface Hydration of Silica on Adsorption of Nitrogen Vapor," Kolloidn Zh. , 19, No. 5 3 572-83 (1957) 18 r . 9 "Chemical Structure of Silica Gel and Its Adsorption Properties," Chemical Surface Compounds and Their Role in Adsorption Phenomena (A. V. Kiselev, ed.) 9 Moscow7"l957, 90-129 (AEC Trans. 3750~5 19. „_-,»« 9 and Muttik, G. G., "Adsorption of Water Vapor by Silica and Hydration of Its Surface," Kolloidn. Zh., 19, 562-71 (1957) 20. Soboleva, L. N. and Kiselev, A. V., "The Adsorption of Methanol Vapors on Hydrated Silica Gel and Quartz," Zh. Fiz. Khimii , 32, U9-57 (1958) 21. Isirikyan, A. A. and Kiselev, A. V., "The Heat of Adsorption of Benzene Vapors on Silica Gels," Zh. Fiz. Khimii , 32, No. 3, 679-88 (1958) 22. Kiselev, A. V.j Leont'yev, Ye. A.j Luk'yanovich, V. M. and Nikitin, Yu„ S., "Structure Changes in the Aluminum Silicate Catalyst Studied by Adsorption and Eiectron-Mictroscope Investigations," Zh. Fiz. Khimii, 30, 2LU9-59 (1956) 23. Kiselev, A. V. j Sabirov, F„ Z.j Ettinger, I. L. and Yanovskaya, M. F. , "Methane Adsorption by Carbon Black and Coal Above and Below the Critical Temperature," Dokl. AN SSSR, 111 , 129-32 (1956) 2lu Kiselev, A. V. and Kovaleva, N. V., "The Nature of the Adsorption of Water Vapor by Active Carbon," Zh. Fiz. Khimii , 30, 2775-86 (1956) 25o Kiselev, A. V„ and Platova, V V„, "Adsorption of a Toluene-Heptane Mixture by Oxidized and Graphitized Carbon," Zh. Fiz. Khimii , 30, 2610-11 (1956) 26. Kiselev, A. V. • Luk'yanovich, V. M e ' and Poray-Ko shits, Ye. A., "Results of a. Complex Study of Structure of Adsorbents and Catalysts by Adsorption, Small-Angle X-ray Scattering and Electron-Microscope Methods," Metody I s s ledovaniya St ruktur y Vysokodispersnykh i Poristykh Tel, A!' SSSR, In-t ""ffiiirulTeuk, Tr. TtoTo l"o~^oveshchaniya ,' 1956 , 161-79 (pflt>. 1958) ' 27 o Kiselev, A. V, and Nikitin, Yu. S. , "The Effect of Thermal and Steam Processing on the Structure and Catalytic Activity of Pellet-Form Aluminum Silicate Catalysts," Khi miya i Tekhn ol. Topliv j Masel, 3, No. 12, 27-32 (1958) ~ ™" — — - - 28. Kiselev, A. V. and Khrapova, Ye. V„, "Adsorption of Nitrogen Vapors on Graphitized Carbon Blacks and Charcoals," Izv. AN SSSR. Otd. Khim. N e , 1958, No. U, 389-U02 29, Kiselev, A. V. • Neymark, I. Ye., Poshkus, L. P. and Piontkovskaya, M. A., "Changes in the Pore Structure of Mg Hydroxide in Thermal Treatment," Izv. AN SSSR. Otd. Khim. N. , lggg , 232-37 -31- 30. Dzhigit, 0. M.j Kiselev, A. V. and Krasil'nikov, K. G., "Effect of the Structure of the Silica Gel on the Velocity of the Sorption of Calcium Hydroxide from Aqueous Solutions," Dokl. AM SSSR , 71, 77-9 (1950) 31. Krasil'nikov, K. G. and Kiselev, A. V., "Absolute Adsorption Isotherms from Solution," Dokl. A^ T SSSR , 77, 10U7-50 (195D 32. Kiselev, A. V. and Kulichenko, V. V., "Triethylamine Adsorption from Vapors and Solutions on Silica Gels of Different Structures," Dokl. AN SSSR , 93, 101-0U (1953) 33. Kiselev, A. V. and El'tekov, Yu. A., "Benzene Adsorption from Heptane Solutions on Silica Gels of Various Structure," Lokl, AN SSSR , 100, 107-10 (1955) ~~ 3k. Kiselev, A. V. and Shikalova, I. V., "Adsorption of Aliphatic Alcohols and Phenols from Aqueous Solutions by Carbons," Zh. Fiz. Khimii , 30, 9U-108 (1956) ~~ ~ 35. Kiselev, A. V.; Nikitin, Yu. S. and El'tekov, Yu. A., "Enhancement of the Adsorption of Organic Substances from Aqueous Solutions by a Decrease in the Pore Size of Active Carbons," Zh. Fiz. Khimii , 30, 33U-39 (1956) 36. Kiselev, A. V.; Kovaleva, N. V.; Korolev, A. Ya. and Shcherbakova, K. D., "Chemical Modification of the Surface of Adsorbents and Its Influence on the Adsorption Properties," Dokl. AM SSSR , 12U, 617-20 (1959) 37. Karnaukhov, A. P. and Kiselev, A. V., "Theory of the Corpuscular Structure of Adsorbents. Capillary Condensation and Sorption Hysteresis in the Spaces Between Regularly Packed Spheres," Zh. Fiz. Khimii , 31, 2635-^3 (1957) 38. Kiselev, A. V„ , "Structure of Certain Corpuscular Adsorbents and Its Influen on Their Adsorptive Properties," Proceedings of the Symposium of the Colston Research Society , 10, 195-226 (19WT ' ~ 39 o __„„_ 9 and Poshkus, D P.., "The Coulomb Energy of Interaction of the OH Group of Silica Gel with the Benzene Molecule," Dokl. AN SSSR , 120, 83U-37 (1958) kO a Idem. , "The Calculation of the Adsorption Energy of Hydrocarbons on Magnesiui Oxide," Zh. Fiz. Khimii , 32, No. 12, 282U-3U (1958) ill, Dubinin, M. M. and Timofeyev, D„ P., "Adsorbability and Physiochemical Properties of Vapors. I. Investigation of the Adsorption of Vapors on Activated Carbon," Zh. Fiz. Khimii , 21, 1213-22 (October, 19^7) 1+2. Dubinin, M. M„, "New Adsorption Methods of Determining the Specific Surface of Adsorbents and Catalysts," Problemy Kinetiki i Kataliza, Akademiya Nauk SSSR, Institut Fizicheskoy Khimii, 5, Metody Izucheniya Katalizatora , 213-29 I4.3. --—j and Zaverina, Ye. D., "Sorption and Structure of Active Carbons. V. Active Carbons from Tar Coke," Zh. Fiz. Khimii , 23, 993-lOOU (19h9) -32- [ i } lo «_ 9 and Zuyev, A. G., "Adsorptive Properties and Structures of Silica Gels and 'Aluminogels ■ ," Dokl. AN SSSR, 69, 209-12 (November, I9U9) \£ c .« — _ 9 and Zaverina, Ye. 1., "Sorption and Structure of Active Carbons VIII. Structure of Active Carbons Obtained by Using Inorganic Activating Substances," Zh. Fiz. Khimii , 2U, U70-78 (1950*) 1;6. Idem., "Sorption and Structure of Active Carbon. IX. Adsorption of Gases by Active Charcoals," Zh. Fiz. Khimmi , 2k, 1262-72 (1950) kl « Dubinin, M. M. and Timofeyev, D. P., "Adsorption of Benzene Vapor on Active Carbon Black," Dokl. AN SSSR , 76, 555-58 (1951) U8„ Polanyi, M. , "Theories of Adsorption of Gases," Transactions of the Faraday Society , 28, 316-33 (1932) U9„ Dubinin, M, M. and Timofeyev, D, P., "Adsorption of Vapors on Active Charcoals in Relation to Properties of Adsorbate," Dokl. AN SSSR , 5U, 701 (19U6) 50. Dubinin, M„ M. and Timofeyev, D, P., "Adsorption of Vapors on Active Charcoal in Relation to the Physical Properties of the Adsorbate," Dokl. AN SSSR , £5* No. 2, 137-UO (19U7) 51 a Idem . , "Calculation of Adsorption Isotherms of Vapors on Active Carbons," Dokl. AN SSSR , 60, 821-2U (19U8) 52„ Dubinin, M. M. and Zaverina, Ye. D., "Adsorption of Gases by Active Carbons," Dokl. AN SSSR , 72, 319-22 (1950) 53o Dubinin, M. M. j Zaverina, Ye. D. and Timofeyeva, D, P., "Sorption and Structure of Active Carbons. VI. The Structure Types of Active Carbons," Zh. Fiz. Khimii , 23, 1129-UO (19^9) 5Uc Dubinin, M. M. , "Porous Structure of Adsorbents," Izv. AN SSSR. Otd. Khim. N. , 1952, 577-82 55. ----- , "Porous Structure of Adsorbents," Compt. Rend. Reunion Ann. Avec Comm. Thermodyam. , Union Intern. Phys. (Paris) , 1952 , Changements de phases, U37-U1 56. ——j "Adsorption of Gases and Vapors and the Structure of Adsorbents," . Uspekhi Khimii , 21, 513-33 (1952) 57. — — s "Influence of a Porous Structure of the Adsorbents on the Form of the Adsorption Isotherm of Vapors," Dokl. AN SSSR , 8U, 539-U2 (1952) 58. — — — , "The Adsorption of Gases and Vapors and the Structure of Adsorbents," Metody Issledovaniya Struktury Vysokodispersnykh i Poristykh Tel, AN SSSR, Tr. Soveshchaniya , 1951, 72-85 (1953) $9» Dubinin, M. M. , "Investigation of the Porous Structure of Active Carbons by Complex Methods," Uspekhi Khimii , 2U, 3-13 (1955) 60. ——j "Investigation of the Porous Structure of Active Carbons by Complex Methods," Quart. Rev. (London), 9, 101-Hi (1955) -33- 61. -r---5 and Zaverina, le. D # , "Sorption of Water Vapor by Activated Charcoal," Izv. AN SSSR. Otd. Khim . H., 195U, 217-2U 62. »— -^ and Serpinskiy, V. V. , "Equation of the Steam Adsorption Isotherm on Activated Charcoal,"" Dokl. AH SSSR , £9, 1033-36 (I9$k) ^3. -....-.^ and Zaverina, Xe. E., "Sorption of Water Vapor by Activated Charcoal," Magyar Tudomanyos Akademia, Kemiai Tudomanyok Osztalyanak Kb'slemenyei , 5, 35-U2, discussion U3-8 U95UJ ~~~ 61u —--j "Surface Oxides and Adsorptional Properties of Active Carbons," Uspekhi Khimii , 2\±, 513-26 (1955) 65. — — >, and Zaverina, Ye. L., "Surface and Sorption of Characteristics of Active Carbons. I. Investigation of Isothermal Sorption of Benzene and Water Vapors," Izv. AN SSSR , 1955, 59U-602 66. -—--j Zaverina, Ye. D. and Serpinskiy, V. V., "Sorption of Water Vapor by Active Carbon," J. Chem. Soc , 1955 . 1760-66 67. — --, and Zaverina, Ye. D., "Nature of the Surface and the Sorption Properties of Active Carbon. II. Study of the Effect of Chemically Adsorbed and Chem- isorbed Oxygen on the Adsorption Properties of Active Carbon with Respect to Water Vapor," Izv. AM SSSR. Otd. Khim. T!. , 1956 , 1038 -U9 68. Dubinin, M. M. , "Surface Oxides and Adsorption Properties of Activated Char- coals," Chemical Surface Compounds and Their Role in Adsorption Phenomena (A. V. Kiselev, ed.J, Moscow, 1957, 9-33 ~~ 69» ——j "Study of the Porous Structure of Solids by Sorption Methods. I. Analysis of Different Methods of Calculating the Distribution of Pore Volumes," Zh. Fiz. Khimii , 30, 1652-61 (1956) 70. — .«,— 5 and Zhukovskaya, Ye. G e , "Study of the Porous Structure of Solids by Sorption Methods. II* Comparison of the Various Methods of Calculating the Distribution of Pores with Respect to Volume and Area on the Basis of Typical Experimental Material," Zh. Fiz. Khimii , 30, 181*0-51 (1956) 71. „-■-, "Adsorption Isotherms," Izv. AN SSSR. Otd. Khim. N„ , 1957 , 392 72. «— .—« f "Methods of Calculating Statistical Distribution of Volume and Surface of Pores of Sor bents on Basis of Sorption Measurements," Me tody Issledovaniya Struktury V ysokodispersnykh i Poristykh Tel, AH SSSR, Inst. Fiz. Khim., Tr7 ~ Vtorogo Soves"hchaniya , 1956 , 107-16 (published 1958) 73. — — — , Zaverina, Ya. D. and Timofeyev, D. P., "Adsorption Properties of Carbon Adsorbents. I. Analysis of Experimental Data Obtained Earlier," Izv. AN SSSR. Otd. Khim. N. , 1957 , 670-77 71; • Dubinin, M. M. and Zhukovskaya, Ye. G., n 0n the Adsorption Properties of the Carbon-Adsorbents. II. Investigation of the Adsorption Properties of Active Coals by Benzene and Nitrogen Vapors," Izv. AN SSSR. Otd. Khim. N. 9 1958 , No. 5 9 535-14U ~~ 4k- 75 « Nikolayev, K. M. and Dubinin, M. M„, "Adsorption Properties of Carbonaceous Adsorbents. III. Isotherms for the Adsorption of Gases and Vapors on Active Charcoals Over a Broad Temperature Range Including the Critical Region," Izv. AN SSSR. Otd. Khim. N , 1958 , 1165-7U 76. Dubinin, M. M„, "Porous Structure and Adsorption Properties of Active Carbons," Indus trial Carbon and Graphi te. Papers read at the Conference held in London , 1957 , 219-30 (Published 195 ») 77. Neymark, I. Ye. and Khatset, F. I., "Effect of the Surface Tension of the Coagulant on the Formation of the Internal Structure of Silica Gels," Kolloidn. Zh. , £, 289-96 (19U7) 78. Neymark, I. Ye.j Khatset, F. I. and Sheynfayn, R. Yuu, "Sorption Properties and Structure of Silica Gels," Dokl ..AN SSSR , 61, 1057-60 (19U8) 79. Neymark, I. Ye. and Khatset, F I„, '•The Importance of Capillary Condensation for Adsorption by Adsorbents of Different Structures," Zh. Fig, Khimii, 27, 50-56 (1953) ~ ~~ 80 o Neymark, I. Ye. and Khatset, F. I., "The Phase State of a Substance in the Adsorbed Layer," Dokl. AN SSSR , ]k, 1S1-SU (1950) 81. Neymark, I. Ye. and Sheynfayn, R. Yu., "The Effect of the Washing Liquid on the Formation Process of the Structure of Silica Gel," Kolloidn. Zh. , 15 , H5-50 (1953) 82. Neymark, I. Ye., "Silica Gel: Its Applications and Methods of Preparation," Uspekhi Khimii , 25, 7U8-69 (1956) 83. Vysotskiy, Z, Z. and Neymark, I. Ye., "The Effect of a Hydrophobic Components of Mixed Sorbents on the Mechanism of -forming Their Porous Structure," Dokl. AN SSSR . £2, 357- ^9 (1953) Qko Neymark, I. Ye.j Sheynfayn, R. Yu., and Svintsova, L. G„, "The Effects of the Surface of Silica Gel on Its Adsorptive Properties," Dokl. AN SSSR , 108, 871-7U (1956) 85. Neymark, I. Ye.j Sheynfayn, R. Yu. and Svintsova, L. G , "Character of Change of Sorption Isotherms of Different Vapors n Fluoridized Silica Gels," Metody Issledovaniya Struktury Vysokodispersnykh i Poristykh Tel, AN SSSR , InstT'yiz. Khirn., TrT" Vtorogo Soveshchaniya , 1956 , 128-36 (Published 195V) 860 Neymark, I. Ye. and Vysotskiy, Z. Z„, "Effect of the Method of Production on the Structure and Sorption Properties of Alumina-Silica Gels," Dopovidi AN URSft, 1953 , 17-20 87 o Vysotskiy, Z„ Z. and Neymark, I. Ye., "Unusual Cases of Porous Structure in the Adsorption Region with Mixed Adsorbents," Ukr. Khim. Zh. , 22, U85-88 88„ Neymark, I. Ye., Rastrenenko, A. I. and Piontkovskaya, M. A., "Preparation of Titanosilica Gels and Their Porous Structure," Kolloidn. Zh. , 19, 32U-32 (1957) ~ -35- 89. Neymark, I. Ye., "The Production of Mineral Technical Adsorbents of Different Pore Structure," Khim. Prompt , 1958 , No. h, 227-3U (1958) 90. Piontkovskaya, M. A. 3 Zhigaylo, la. V.j Yeremenko, L A. and Neymark, I. Ye., "Change of Structure and Adsorption Activity of Aluminum Oxide Hydrate Depending on Its Formation Conditions," Kblloidn. Zh. , 21, 3U7-50 (1959) 91. Neymark, I. Ye. and Slinyakova, I. B., "Preparation and Adsorption Properties of Ferrogels with Varying Porosity Structure," Kolloidn. Zh., 21, 3UO-U6 (1959) 92. Neymark, I. Ye. and Piontkovskaya, M. A., "Production of Gels Having Differing Porous Structures from Metal Hydroxides and Silicic Acid and Study of Their Properties," Ukr, Khim. Zh., 25, 322-25 (1959) 93. Zhdanov, S. P., "The Problem of Computing the Structure of Porous Sor bents on the Basis of Sorption Isotherms," Dokl. AN SSSR , 61, No. 5 (19U8) 9)4. „„_„„ 5 "Comparative Study of the Structure of Porous Glasses by Adsorption Methods and with an Electron Microscope," Dokl. AN SSSR , 82, 28l=8JU (1952) 95. — — '•— s "Application of the Theory of Capillary Condensation to the Investigation of the Structure of Porous Adsorbents," Me tody Issledovaniya Struktury Vysokodis- persnykh i Poristy kh Tel, AN SSSR, Tr. Soveshchaniya , 1951, 133-Wi (19537 96. Zhdanov, S. P., "Relations of Dehydration and Hydration of the Surface of Porous Glasses to Their Adsorption Properties," Dokl. AN SSSR, 100, 1115-18 (1955) 97 . ____-, "Water Adsorption on Quartz Ground in Vacuo," Dokl. AN SSSR, 115, 9384a (1957) 98. — — $ and Kisselev, A. V„, "The Chemical Structure of the Surface of Quartz and Silica Gel," Zh. Fig. Khimii, 31, 2213-22 (1957) 99c — «— , The Influence of Dehydration and Hydration of the Surface of Porous Glasses on Their Adsorption Properties," Surface Chemical Compounds and Their Role in Adsorption Phenomena (A. V. Kiselev, ed.), Moscow, 1957, 139-57"" 100. — — — - , "Discussions on the Part Played by the Surface Hydroxyl Groups of Porous Glass in the Adsorption of Water," Zh. Fiz . Khimii, 1958 , 32, No. 3 S 699-706 101 — - — 9 "Application of the Adsorption Method for Studying the Etching Structures in Porous Glasses," Metody Issledovaniya Struktury Vysokodispersnykh i Poristykh Tel, AN SSSR, Tr. Vtorogo Soveshchaniya , 1956, 117-27 (Pub a 1958)' — — 102 o — — 5 and Poray-Ko shits, Ye. A., "Comparison of Results of Study of Structures of Porous Glasses by Methods of Adsorption and Small-angle X-ray Scattering," Ibid., 180-89 103. Yerrnolenko, N. F. and Levina, S. A., "Structure and Adsorptive Activity of Aluminum Hydroxide as a Function of the Mode of Formation," Trudy 3-ey Vsesoyuz noy Ko nferent s li po Kolloidnoy Khimii, Akademiya Nauk SSSR, Otde lenie 'KhimicheskiMTNauk, Minsk, 1953, 276-8/j. ' — — _ -36- lOlu Idem., "Structure of Aluminum Hydroxide and Its Absorptive Capacity, u Izv. AH BSSR , 19$h 3 No. 1, 107-13 105. Idem., "Structure and Adsorptive Activity of Aluminum Chromium and Iron Hydroxides as Functions of the Condition of Their Formation," Kolloidn. Zh. , 17, 287-9U U955) 106. Idem., "Adsorption Activity and Structures of Gel Sesquioxides in Relation to Their Thermal Treatment," Sbornik Nauchnykh Rabot, Akademiya Nauk Belorusskoy SSR, Institut Khimii , 1958 , No. 6, 1US-S3 107 Id em. , "Adsorbent Activity of Cadmium Hydroxide in Relation to Its Methods of Preparation," Kolloidn. Zh. , 1£, 673-77 (1957) 108. Yermolenko, N. F. and Krivchik, Z. A., "The Structure and Adsorptive Activity of Peat Charcoal," Sbornik Nauchnykh Rabot, Akademiya Nauk Belorruskoy SSR, Institut Khimii , 1956, No. 5, 20U-12 109o Kargin, V. A. and Gatovskaya, T. V., "Sorption Properties of Crystalline Polymers," Zh. Fiz. Khimii , 29, 889-91 (1955) 110. Idem. , "Sorption of Hydrogenated Monomers by Amorphous Polymers in the Vitreous State," Zh. Fiz. Khimii , 30, 2051-56 (1956) 111. Idem., "Sorption of Low-Molecular-Weight Substances by Amorphous Polymers TrTa Highly Elastic State," Zh. Fiz. Khimii , 30, 1852-5U (1956) 112. Kargin, V. A., "Sorptive Properties of Glasslike Polymers," Journal of Polymer Science, 23, No. 103, U7-55 (1957) 113. Bykov, V. T., "Sorption and Bleaching Properties of Native Sor bents," Izv AN__SSSR. Otd. Khim. H., 1951 , 678-85 "" HUo — — s and Kuadzhe, M. I., "Sorption and Catalytic Properties of Some Bleaching Earths," Izv. AN SSSR. Otd. Khim. H. , 1951 , U87-99 ll£ 8 _ "Structural Types of Natural Sorbents " Dokl. AN SSSR, 79, 621-2U (1951) ~ ~ — 116. — — , "Natural Sorbents of the Far East. II. Sorption of Benzene Vapors by Natural Sorbents and Structure of the Sorbents," Izv. AN SSSR. Otd. Khim. N. , 1952, 583-91 ~ ' -~ 117. — — -, Gerasimov, V. G. and Zalevskiy, N. I., "Study of the Porosity of Natural Sorbents by the Methods of Capillary Condensation and Mercury Pressure," Izv. AN SSSR. Otd. Khim. N. , 1957, 1250-52 118. Zalevskiy, N. I. and Bykov, V. T., "Application of the Method of Mercury Porosimetry to Measurements of Macroporosity of Natural Adsorbents," Metody Issledovaniya Struktury Vysokodispersnykh i Poristykh Tel, AN SSSR, Inst. Fizo Khimii, Tr. Vtorogo Soveshchaniya ', 1956, 267-71 (Pub. 1958) 119. Bykov, V. T„ and Presnyakova, 0. Ye., "The Dynamic Method of Investigation of the Structure and Specific Surface of Adsorbents," Dokl. AN SSSR , 112, 677-80 (1957) -37- 120. Bykov, V. T. and Presnyskova, 0. Ye., "Dynamic Method of Study of the Structure and Specific Area of Adsorbents," Metody Issledovaniya Struktury Vysokodis- persmykh i Poristykh T el, All SSSR, Inst. Fiz. Khimii, Tr. Vtorogo Soveshchaniya, ^57~22Ii-30 (Pub. 19^B7 121. Tsitsishvili, G. V., u Some Results of Adsorption-Structural Investigations of Georgian SSSR Bentonitic Clays," Trudy Instituta Khimii imeni P. G. Melik- ishvili, Aka demiya Nau k Gruzinskoy SSSR , 1956 , No. 12, 235-50 122. Burshteyn, S. I.j Davtyan, 0. K. and Tikhonyuk, R. V., "Adsorption Properties of the Dark-Green Earths of the Odessa Deposit," Trudy Odesskogo Gosudarstven° nogo Universiteta imeni I. I. Mechnikova, Seriya Khim. Nau k,~ ~lU6 , No. 5 3 83-90 123. Bregvadze, V., "Sorption Ability of the Chenushy Bentonite Clay," Trudy Tblis skogo Gpsudarstvennogo Universiteta imeni I. V. Stalina , 62, 197-209 (1957T~(Russian Summary, 209-10) — — — - . _ 12lu Slisarenko, F s A. j Timofeyeva, Ye. M«; Sorokin, S. I. and Zabelin, V. A., "Evaluation of the Structure of Volga Diatomites by the Sorption of Water and Benzene Vapors," Zh. Prikl. Khimii , 30, 1127-35 (1957) 125 . Kuadzhe, M, I;, "Sorptive and Catalytic Properties of Some Natural Formations," Zh. Prikl. Khimii, 31, 1001-06 (1958) 126„ Dreving, V. P. • Kiselev, A. V. and Dikhacheva, 0. A., "Adsorption of Nitrogen Vapors on Silica Gel at Low Temperature," Zh. Fiz. Khimii , 25, 710-18 (1951) 127. Idem,, , "The Absolute Isotherms for the Adsorption of Nitrogen Vapor on Silica Gel, Alumino-Silica Gel and Barium Sulfate,"" Do kl. AH SSSR, 82, 277-80 (1952) 128„ Kiselev, A. V.j Kiselev, V. F. 5 Mikos-Avgul, N. N.j Muttik, G. G.j Runov, A. D. and Shcherbakova, K. D., "An Automatic Calorimeter with Constant Heat Exchange for the Measurement of the Heat of Adsorption of Gases and Liquids," Akademiya N a u k S S S R_g_ T iudy_ In s t i tu t e Fjzicheskoy Khimii, No. 1, No vye Metody Fiz . Khim. -^^•^IPZ^^I ^Ygl "^ 1110,3 ^ Tavleniy, 68-88 (1950)"" 129o Isirikyan, A. A. and Kiselev, A. V., "Maximums of the Heat of Adsorption at Complete Capillary Condensation of Vapors," Dokl. AN SSSR, 110, 1009=12 (1956) 130 o Idem., ,f The Heat of Adsorption of Benzene and Hexane Vapors on Ignited and Hydrated Silica," Dokl. AN SSSR , 115 , 3U3-U6 (1957) 13L Idem., "Heat of Adsorption of Benzene and Hexane Vapors on Powered Quartz," jjokl. AN SSSR, 119, 731-314 (1958) 132 „ Idem. , "The Heats of Adsorption of Hexane and Heptane Vapors on Silica Gels," Zh a Fiz. Khimii , 31, 2127-37 (1957) 133» Isirikyan, A. A.j Kiselev, A. V. and B. A. Frolov, "Heat of Adsorption of n-alkanes on SiO^ Gel," Zh. Fiz. Khimii , 33, 389-9U (1959) 13U. Avgul", N. N.j Dzhigit, 0. M. and Kiselev, A. V. , "Adsorption of Vapors on a Nonporous Active Carbon Lampblack," Dokl. AN SSSR , 86, 95-8 (1952) -38- 135. Avgul', N. N. ; Dzhigit, 0. M. 5 Kiselev, A. V. and PheberhaWe, FT. ?\. "Determination of the Adsorption Isotherm and the Differential Heat of Adsorption of Water on Carbon Black," Dokl. AM SSSR , £2, 105-8 (1953) 136. Avgul', N. N.j Dzhigit, 0. M. and Kiselev, A. V., "Capillary Condensation of Vapors and Pore Structure of Active Carbons," Dokl. AH SSSR , 89, 97-9 (1953) 137. Idem. , "Isotherms and the Heat of Adsorption of Methyl Alcohol on Charcoal," Dokl. AN SSSR , 92, 1185-88 (1953) 138. Avgul', N, M.j Dzhigit, 0. M.; Kiselev, A. V. and.JShcherbakova, K. D OJ "The Isotherm and the Heat of Adsorption of Steam on (Activated) Carbori, ,t Dokl. AM SSSR , 101 , 285-88 (1955) 139. Avgul', N. N.j Dzhigit, 0. M. and Kiselev, A. V., "Capillary Condensation of Various Vapors on a Coarse Porous Silica Gel," Zh. Fig. Khimii , 29, 316-26 (1955) ' -~ 1U0. Avgul', N. N.j Berezin, G. I. 3 Kiselev, A. V. .and Dygina, I. A., "Heat of Adsorption of Benzene Vapors on Carbons, Thermodynamics and Adsorption Forces," Izv. AN SSSR. Otd. Khim. N. , 1956, I30J4-II 1U1. Avgul', N. N. and Kiselev, A. V., "Energy of Adsorption Forces and Heat of Adsorption for Simple Molecules on Graphite," Izv. AN SSSR. Otd. Khim. N. , 1957 , 230-32 ll|2. Avgul 1 , N. N.j Berezin, G. 1, 3 Kiselev, A. V. and Dygina, I. A., "Heat of Adsorption of Hexane Vapors Upon Carbon Black. Thermodynamics and Adsorption Forces," Zh. Fiz. Khimii , 30, 2106-21 (1956) llt3. Idem., "Energy of Adsorption Bond and Heat of Adsorption of n-Alkanes on "Carbon Black," Izv. AN SSSR. Otd. Khim. N., 1957 , 1021-31 (1957) II4U. Avgul', N. N. and Kiselev, A. V., "The Adsorption Energies of Hydrocarbons on Graphite," Dokl. AM SSSR , 112 , 673-76 (1957) lU5o Avgul', N. N.3 Isirikyan, A. A.j Kiselev, A. V.; Dygina, I. A. and Poshkus, D. P., "Adsorption Equilibriums and the Energy of Adsorption Forces," Izv. AN SSSR, Otd. Khim. M. , 1957 , 131U-27 IU60 Avgul', TI. N.; Berezin, G. I.; Kiselev, A. V.; Dygina, I. A. and Muttik, G. G., "The Effect of Porosity of Graphite Adsorbents on the Adsorption and the Heat of Adsorption of Hexane Vapors," Zh. Fiz. Khimii , 31, 1111-25 (1957) lii7. Avgul', No M., "Influence of the Chemical Structure of the Surface of Carbon Blacks and of Their Graphitization on the Isotherms and Heats of Adsorption of Vapors," Surface Chemical Compounds and Their Role in Ad sorption Phenomena (A- V. Kiselev, ed.J, Moscow, 1957, 3U-5S (AEC Trans. 3750, September 1959) 1U8. Avgul', N. N.j Berezin, G. I.; Kiselev, A. V. and Dygina, I. A., "Heat of Adsorption for a Number of Isoalkanes, Maphthenes, and Toluene on Graphitized Carbon Black," Izv. AM SSSR. Otd. Khim. N. , 1959 , 787-96 -39- lli c '. Bering, B. Po and Serpinskiy, V. V., "The Theory of Monomolecular Adsorption on Homogeneous Surfaces, " Dokl. AM SSSR , 79, 273-76 (1951) 150. Idem., "Heat of Adsorption," Izv. AN SSSR. Otd. Khim. N. , 1957 , 125 1S>1, Idem,, "The Computation of Heat and Entropy of Adsorption from One Adsorption Isotherm," Dokl, AH SSS_R, llU, 125U-56 (1957) 1^2. Idem, , "The Measurement of the Adsorption of Nitrogen on Sodium Chloride Using a Quartz Microbalence with High Sensitivity," Dokl. AN SSSR , 9I1, U97-500 (195U) ~~ 153. Bering, B. P.; Dubinin, M M.j Zhukovskaya, Ye. G. and Serpinskiy, V. V. , "Study of the Porous Structure of Solids by Sorption Methods. III. Weight Methods of Measuring Isotherms of Sorption and Desorption of Nitrogen and Benzene Vapors," Zh. Fjz. Khimii, 31, 712-16 (1957) 15U. Vasil'yevj B. N.j Bering, B, P.* Dubinin, M. M. and Serpinskiy, V. V, "Adsorption at High Pressures," Dokl. AN SSSR, 111*, 131-3U (1957) 155. Bering, B. P. and Serpinskiy, V. V., "Volumetric-Gravimetric Method for Measuring the Adsorption of Gas Mixtures," Dokl. AN SSSR , 90, 811-11* (1953) 156. Idem. , "Simultaneous Adsorption of Ethylene and Propylene on Active Carbon," IbklT AN SSSR, 85, 1065-68 (1952) 157. Bering, B, P. and Serpinskiy, V. V., "Adsorption of Mixtures of Gases. I. Adsorption of Ethylene and Carbon Dioxide on Active Carbon," Zh. F iz. Khimii , 26, 253-69 (1952)' ~~~~ 158. Idem., "Adsorption of Gas Mixtures. II. Adsorption of Ethylene and Propylene on Activated Charcoal," Izv. AN SSSR. Otd. Khim. ??. , 1952 , 997-1007 l59o Idem. , "Adsorption of Mixtures. III. Possibility of a Statistical Treatment of the Adsorption of a Mixture of Gases," Bulletin of the Acad emy of Sciences US SR, Div. of Chemical Science, 1953, 33-U1 (Eng. trans. ~T~ 160. 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V . , "Adsorption of individual Hydrocarbons on Commercial Aluminum Oxide," Vestnik Moskovskogo Universitets, Seriya Matematiki, Mekhanki, Astronomii, Fiziki i Khimii , 13, Mo. 2, 233-UO (1958) 167. Kaganer, M„ G., "The Isotherm of the Adsorption of Nitrogen at Low Pressures," Doki. AN SSSR , 122 , No. 3, U16-19 (1958) 168. Il'in, 3. V., "The Nature of Molecular Attraction in Adsorption," Zh. Neorgan. Khimii , 1, 1559-65 (1956) 169. Radushkevich, L. V., "Capillary Condensation of Vapors in Highly Lispersed Systems. I. Calculation of the Capillary Condensation in the Neighborhood of the Contact Points of Spherical Particles," Izv. AN SSSR. Otd. Khim. N. , 1952, 1008-20 170. — .— -, "Capillary Condensation of Vapors of Highly Lispersed Systems. II. Evaluation of Some Approximate Calculations of Capillary-Condensed Volumes," Izv. AN SSSR. Otd. Khim. N., 1958 , 285-89 171. — — , "The Capillary Condensation of Vapors in Highly Lispersed Systems. III. Capillary Condensation in Cells Made by Two Contacting Spheres of Lifferent Radii," Izv. AN SSSR. Otd. Khim. N. , 1958 , 1*03-10 172„ Radushkevich, L. V., "Adsorption Potential Near Spherical Particles of Colloidal Eimensions," Lokl. AN SSSR , 119, 530-32 (1958) 173o Timofeyev, L. P., "Equations of the Kinetics of Adsorption for Active Carbons," Zh„ Fiz. Khimii, 27, 16U2-U9 (1953) 171+. — — — , "Eistribution of Absorbed Vapors in Active-Carbon Grains with a Non- linear Adsorption Isotherm," Zh. Fiz. Khimii , 29, No. h, 723-29 (April, 1955) 175. -__-_, "On the Rate of resorption," Zh. Fiz. Khimii , 32, No. 11, 2U83-86 (1958) 176. «v« -— , and Voskresenskiy, A. A., "The Investigation of the Mechanism of Internal Dif fusion by the Method of X-ray Lias copy," Lokl. AN SSSR , 122, No. 3, U3U-36 (1958) " — 177» — — ~ , "The Adsorption by a Layer of a Sorbent One Grain Thick," Zh. Fiz. Khimii, 32, 2005-13 (1958) 178. Bikson, Ya. M. , "Evaluation of the Length of the Working Layer of a Sorbent in Sorption Eynamics on a Real, Granular Adsorbent," Zh. Fiz. Khimii, 27, 1530- 38 (1953) 179 o — — , "Lynamics of the Sorption of Two Components from a Mixture," Zh. Fiz. Khimii, 28, 1017-2U (195U) 180. Grinberg, A. L.« Strazhesko, E. N. and Tovbin, M. V., "The Cause of the Retentive Ability of Porous Adsorbents," Zh. Fiz. Khimii , 28, 81-6 (l°5U) -ill- 181. Tovbin, M. V. and Grinberg, A. D., "Dynamics of Desorption from Porous Adsorbents," Zh. Fiz. Khimii , 28, 1755-61* (195k) 182. Memo, "Dynamics of the Desorption of Iodine from Activated Charcoal," IT mikovi Zapiski, Kilvs'kiy Derzhavniy Universitet imeni T. G, Shevc henka, W, No. 15, ZbirTTIFTg^imr'Fak . , No. 8, 39-U3 (1957; ~~ -— 183. Tovbin, M. V, and Boyevudskaya, Z, L. , "Self -Ad sorption. I. Surface Tension of Salt Solutions," Ukr. Khim. Zh. , 22, 173-79 (1956) 181*. Tovbin, M. V. and Savinova, Ye. V. , "Self Adsorption. II. Relation Between Surface Tension and Radius of Surface Curvature," Ukr. Khim. Zh., 23, ll*6-5>l ( 19 57) — — — 185. Tovbin, M. V. and Bagliy, T. G., "Kinetics of the Desorption of Acetic Acid from Activated Charcoal," Nuskovi Zapiski, KiiVs'kiy Derzhavniy Universitet imeni T. G. Shevchenka , 167" Mo. 15, Zbirnik Khim. Fak ._, Mo. K, 31-7 (1957 ) 186. Gorchakov, N. I. and Pogodin, I. I., "Desorption of Solvents from Activated Charcoal by Inert Gases," Zh. Prikl. Khimii , 31, 60-5 (1958) 187. Bolonogov, K. N. and Popov, B. 1, 9 "The Determination from the Kinetic Data of the Reactionary Constant and of the Effective Diffusion Coefficient Inside a Porous Catalyst," Zh. Fiz. Khimii , 2£, 1187-92 (1955) 188. Myasnikov, I. A. and Gol'bert, K. A., "The Internal-Diffusion Sorption Dynamics in the Linear Region," Zh. Fiz. Khimii , 27, I3II-2I4 (1953) 189. Alekseyeva, A. V. 'and Gol'bert, K. A., "Kinetics of the Physical Adsorption of Ethylene from Mixtures," Dokl. AN SSSR , 113, 1310-13 (1957) 190. Romankov, I. P. G. and Lepilin, ^. N., "The Dynamics of Adsorption in a Fluidized Layer of Adsorbent," Zh. Prikl,* KMmi-i- > 29 , 5U8-53 (1956) 191 o Romankov, P. G., "Approximate Equations of the Kinetics of the Desorption Process," Izvestiya Vysshikh Uchebnykh Zavedeniy. Khimiya i Khimcheskaya Tekhn ologiya, 1958," "No. 3, 160-63 192. Planovskiy, A. II. and Vlasenkov, L. A., "Kinetics of the Process of Continuous Adsorption in a Fluidized Bed," Khimiya Tekhnol. T ppliv j Masel, 3 5 No. 9j 7-13 (1958) ~~~~ "" — — — 193- Regak, M„ Ya. and Smirnov, N. I., "Adsorption Processes," Zh. Prik l. Khimii, 28, 262-67 (1955) 19U« Idem. , "J\ Study of Adsorption Processes. II. Adsorption of Unsaturated Gases by Activated Charcoal," Zh. Prikl. Khimii , 28, 1*33-36 (1955) 195. Liubimov, I. V. and Srairnov, N. I., "Laws of Mass Transfer in Adsorption," Zh. Prikl. Khimii , 30, No. 9, 11*08-12 (1957) 196. Shevelev, Ya. V. , "The Diffusion of Adsorption Fronts. I. Quantitative Characteristics of Diffusion," Zh. Fiz. Khimii , " 31 , 960-71* (1957) ■-1*2- 197c Vagin, Ye, V. and Zhukhovitskiy, A. A., "The Theory of Thermo -Ad sorption Separation," Zh. Fiz. Khimii , ]2 f No. 10, 2362-73 (1958) 198. Gebler, I. V. and Stramkovskaya, K. K., "The Adsorption of the Heavy Metals from Solutions of Their Salts by Brown Coal," Izvestiya Vostochnykh lilialov Akademii II auk SSSR , 1957, No. 12, 78-82 199. Starik, I. Ye, and Skul'skiy, 1. A., "Adsorption of Microquantities of Radio- active Elements on Non-Ion Exchange Adsorbents," Izv. All SSSR. Otd. Khim. N. , 1958, No. 10, 1278-79 200. Voznesenskiy, S. A.j Puzako, V. D. and Levasheva, L. B. , "The Influence of a Non-Aqueous Solvent on the Adsorption of Radioactive Micro components by a Number of Adsorbents," Nauchnyye Doklady Vysshey Shko ly. Khimiya i Khirniches- kaya Tekhnologiya . 1958, No. 3, U52-5U 201. Sheka, I. A. and Voytovich, B. A., "Adsorption on Silica Gel of Tetrachloride and Methoxychlorides of Zr and Hf," Jkr. Khirru Zh. , 25, No. 3, 317-21 (May - June, 1959) 202. Belen'skiy, M. S. and Alkhazov, T. G., "Adsorption of Salts by Activated carbon. I. Kinetics of Adsorption of Silver Salts from Aqueous Solution by Activated Carbon," Trudy Azerbaydzhanskogo Industialnogo Instituta im„ M. Azizbekova , 1956 , No. 12, 106-7 ~~~ ~~~ " 203. Strazhesko, D. N.. and Tartakovskaya, B. E., "The Mechanism of Acid Adsorption on Activated Carbon from Nonaqueous Solutions," Dokl. AN SSSR , 98, 107-10 (195U) 20U. Lun'onok--- Burmakina, V. A. and Strazhesko, D. M., "Investigations of Electro- chenical Adsorption of Ions from Dilute Solutions by the Method of Tagged Atoms," Eopovidi AN URSR, 1955 , No. 2, 171-7U 205. Strazhesko, 1 M. and Yankova'ka, G. P., "The Adsorption of Electrolytes by Acidified Carbon from Nonaqueous Solvents," loppvidi AN URSR , 1956 , Shh-hl 206. Strazhesko, 1. M. and Lun'onok- Burmakina, V. 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F. , "The Effect of Functional Groups in Organic Acids on Their Adsorption in Solutions,," Sbornik Nauchnykh Rabot , Akademiya Nauk Belorusskoy SSR, Institut Khimii , 1956 , No. 5, 188-93 — ~ 212. Kharin, A. K. and Svintsova, L. G., "The Dynamics and the Adsorption of Iodine on Carbon from Aqueous and Alcohol Solutions," Zh. Fiz. Khimii , 30, 1776-91 (1956) ~~ — — 213. Kharin, A. N", and Voytko, L. M. , "Uptake of Substances by Granulated Carbon from Flowing Solutions. III. Study of the Sorption Dynamics for Essential Oils Over a Large Range of Flow Velocities of the Solutions," Zh. Prikl. Khimii, 22, 1191-1207 (19U9) ' ' 21U. Kharin, A. N, and Ampilogov, I. Ye., "A Comparative Evaluation of the Part Played by Kinetic Factors in the Dynamics of Adsorption of Acetic- and Butyric Acid from Their Aqueous Solutions on a Charcoal Bed," Zh. Fiz. Khimii , 32, No. 2, 3U.-4+8 (1958) — — . 215. Bonetskaya, A. K. and Krasil'nikov, K. G., "The Adsorption of Aliphatic Alcohols on Silica Gel and Powdered Silica Gel from Solutions," Dokl. AN SSSR, lilt, 1257-60 (1957) ~~ — ~~ 216. Starobintsev, G. L. and Bol'shova, T. A., "Determination of Normal Hydro- carbons in Paraffins by Adsorption Analysis," Zh. Analit. Khimii , 13, 235>-l|l (1958) 217. Smirnova, I, V.; Topchiyeva, K. V. and Mil'kova, L. P. 3 "Adsorption on Industrial Catalysts from Solution of Aralkyl Hydrocarbons," Zh. Fiz. Khimii , 32, U3- 8 (1958)' 218. Smirnova, I. V. and Topchiyeva, K. V., "Adsorption of Individual Hydrocarbons on Industrial Aluminum Oxide," Vestnik Moskovskogo Universiteta, Seriya Matematiki, Mekhaniki, Astronomii, Fiziki, i Khimi i, 1958 , MoT 2, 2 3' J -21+0 219. Frumkin, A. M„, "The Adsorption Phenomenon and Electrochemical Kinetics," Uspekhi Kh imii, 2U, No. 8, 933-50 (1955) 220. Dukhin, S. S. and Eeryagin, B. V., "The Dlffusional-Electrical Potential of a Falling Drop with an Adsorption Layer," Dokl. AN SSSR , 121, No. 3, 503-06 (1958) — ~ — — 221. Obrucheva, A. D., "An Investigation of the Adsorption of Cations on Platinized Platinums by Measuring the Adsorption Potentials," Dokl. AN SSSR , 120, No. 5, 1072-75 (1958) ~~ ™ 222. ——j "Investigation of the Adsorption of Ions on Platinized Platinum by Measuring Adsorption Potentials," Zh. Fia. Khimii , 32, No. 9, 2155-61; (1958) 223. Balashova, N. A., "Adsorption of the Bromide and Iodide Ions on Platinum," Zh. Fiz. Khimii , 32, No. 10, 2266-73 (1958) 22lu Nikolayeva, S. A. and Rakhnu, S., "The Effect of the Nature of Cations on the Specific Anion Adsorption/ Zh. Fiz. Khimii , 32, No. 5, 1059-62 (1958) 22^. Krasikov, B. S. and Pevnitskaya, M. V., "On the Problem of the Character of Adsorption Layers on the Surfaces of Solid Electrodes, 1 X£5Ji!^Ji£^^ r£> Wo ° 2 * 133-38 (1958) 226* Kheyfets, V„ L .j Frasikov, B. S.j Sysoyeva, V. V„ and Guseva, I. V , "Adsorption of Aliphatic Alcohols 8 I Adsorption on the Mercury Electrode ? t! Vestao Leninrr Un-ta-, 12., No 22 , Ser ._ JFiZo_ i_ j^himii , No. I, 128«3F7l956l "" "" 22? 9 Iderrio „ w Ads option of Aliphatic A]cohols a II Adsorption on Solid Electrodes, 8 ' Vc strip leningr.o Un-ta, 12, No« h s Se ro__Fiz i Khimii, No. 1, 127-33"TT5575' ' 228 Ideriios "Investigation of Adsorption of Aliphatic Spirits, III, Absorption at the Transit from Aqo.eo.us to Alcoholic Solutions , w llBlIL^J^B^IME Jll^^JlzE,* JE^j2JL^P£!^i^ §£:* ^ 0o ^ l » 1^8-51 (1957) 229. Kheyfets, V, L. and Krasikov, B. S., "The Effect of Adsorbed Hydrogen on the Zero Charge Potential, .of Some Metals,'* Dokl„ AN SSSR, 109, 586-88 (1956) — — 230o Kheyfets, V. L„ and Ki*aaikav., B„ So, ""The Nature of Adsorption Layers of the Surface of Solid Metals," Zrw FiJ5.» Khimii, 31, 1227-3li (1957) 231 Balandin, A A., '"The Free Energy of Adsorption in Dehydroge nation for a Heterogeneous Surface, 81 BgM 1 o_, J AN,_SSSR, 93, 55-8 (1953) 232„ «— - 5 and TolstopyatoYa, A„ A c , "Components of the Activation Energy and the Problem of Choosing Catalysts, n BokloANSSSR, 9k 9 =52 (19510 233 «, — — , "Catalysiv 1 Adsorption in Behvdrogenation," Dokl A N_SSSR , 93, 273-76 (1953) 23iio — ■ — -, and Klabunovskiy, Ie I OJ "Kinetics of the 2-Butanol Dehyd« ration Over Nickel « Dokl<, AN SSSR, 98, 783-86 235o — =., "The Multiplet Theory and the Principle of Detailed Equili- brium The Mechanism of Hydrogenation and Dehydrogenation," Dokl, ANJSSR, 97, 1&9-52 (193 ' 2360 -- — , "Catalytic Layer Their Effect on Activation Energy, 1 * Dpklo__AN SSSE, 97, 667-70 (1951-0 237 o — — , "Bond Energy and Heterogeneous Catalysis," Dokl„ AN S5SR, 107, 85-8 (19.56) — — 238. —-.«= s "Theory of the Selectivity of Catalysts," Uchenyye Zapiski Moskovskijr Ordena Lenina G o sudarsjgrennyy ^^i-ygj^^t^^jmenlT M . ^TT 239° Balandin, A. A., "Intermediate Surface Forms, la Catalysis,** Surfa ce £^EiS^,ilSS5HS^£, ^2!~L ^^IlJ^S^L J^L^B2E^t2B Phenom ena (A. Kiselev,"edT]7~^ osc " ow "^hilversity Press, l95>7« r 30i7^IITT.AEC Trans, 3750 11959) 2lt0 o *—«««, Bogdanova* K and Shcheglova, A Q P a , 88 The Free Energy of the Adsorptive Displacement of Butylene by Water on -a Catalytic Surfac@ s ! » Iz^J^L§^jl.J9^lJ^^j.J^» 19&>> 725-33 2ljlo *-<■ «, "Precise Method for Betensining. Relative Adsorption Coefficients Izv. AN SSSH. Otd B Khim. N , 1957. 882=83 2li2o --.— , and Teteni, P„, "Dehydrogenation Kinetics of" Alcohols Over Precipitated Copper Catalysts/" DokloJLNj3SSR, 113, 1090-93 (1957) 2i}3« ««— , Turova-Poly&k, M 9 B | Agronomavj A, l'e<,j Khorlina, I. 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Ye., "Effect of Specificity of Some Unsatu- rated Organic Compounds on Their Adsorption and Catalytic Properties,"' Uch Zap. Kishinevsk. Un-t, _7$ 13-19 (1953) 261. Shlygin, A. I. and Permitina, N. G., "Dependence of Adsorption and Catalytic Properties of a Catalyst on Its Structure," Kataliticheskoe and Gidrirovanie i Okislenie, Trudy Konfe rentsii po Kataliticheskomu Gidrirovaniyu i Okislenlytu 262. Vol'kenshteyn, F. F.<, "Chemical Adsorption on Ionic Crystals," 1 Zh. Fiz e Khimii , 26, 11,62-71 (1952) 263. — , "Theory of Activated Adsorption," Zh. Fiz. Khimii, 27, 159-66 (1953) 26iu -.—» - 3 "Electronic Processes in Chemisorption. I c , "Bulletin of the Academy of Science s, Division of Chemical Science , 19 S3 , 701-05 (English translation)" 26-0 — -, "Electronic Processes in Chemisorption. II., "Bulletin of the Academy of Sciences, Division of Chemical Science , 1953, 865-70 (English translation) 266. ~— -, "Activated Absorption on Semiconductors," Uspekhi Fizicheskikh Nauk , 50, 253-70 (1953) 267. Vol'kenshteyn, F. F., "Two Types of Homopolar Bond in Chemical Adsorption," Zh. Fiz, Khimii, 28, l|22-32 (195U) 268. Bonch-Bruyevich, V. L. and Vol'kenshteyn, F. F., "The Notion of Inhomogene- ous Surface in the Theory of Adsorption," Zh. Fiz. Khimii, 28, 1219-2U (1951) -hi- 269 o Vol'kenshteyn,, F. F , "Mechanism for the Dissociation of Diatomic Molecules Adsorbed on the Surface of a Semiconductor/' Izv AN SSSR. Otd„ Khim„ N C3 19 57 3 H43-56 270c, —— , "Various Types of Bonds in Cherni sorption on Semiconductors/ 1 Bulletin of the Academy of Scien ces., Division of Chemical Science., 19 57 3 No Q 9 916- 2.3 TEnglish translationT" 271o — - -, "Mechanism of Catalytic Action of Semiconductors /' Bulletin of the Academy of Science s j Division of Chemical Science , 1957 $ NoT~B7~92li-28 272* ~ — , "Modern State of Electronic Theory of Catalysis on Semiconductors/' Uspekhi Khiiaii 3 27 3 130li-20 (1958) 273, — — 3 "The Semiconductor Surface Charge in Adsorption/ 8 Zh, Fiz„ Khimii , 32 , 2383-91 (1958) ~~ 27 ho =——5 and loffe, I lo, "The Direction of the Contact Oxidation Reaction on Semiconducting Catalysts (Example of the Oxidation of Benzene)/' Dokl a AN SSSR, 118, 7U7-50 (1958) 27 5o Bonch-Bruyevich, V G L c and Glasko 3 V. B 0> "On the Theory of Chemical Ad- sorption on Metals/' Vestni k Moskovskogo Universit eta , Seriya Matematiki,, Mekhanikij Aatronomii, FizikiV i Khimii 3 1958 3 "No7~^I ~9J-10lt 276 Kogan, Sh M 65 "The Statistics of Adsorbed Particles in the Electronic Theory of Chemisorption/* Zh c Fiz„ Khimii , 33 3 No e 1 3 156-60 (1959) 277 o Lyashenko 3 V„ l c and Stepko 3 I e Io 3 "Influence of Adsorption on Surface Charges and Conductivity of a Semiconductor /' Izv a AM SSSR. g er e Fizi- cheskaya 3 16, 211-17 (1952) 278 «, Lyashenko, V„ I og "Change in the Work Function and Conductivity of Molyb- denum Sulfide Under the Influence of Adsorption/' Tr c In-ta Fiziki 5 AN Ukr. SSR, U, 33-6 (1953) 279o — — 3 "The Adsorption of Molecules and the Photoconductivity of Cuprous Oxide /' Doklo AN SSSR 5 87, No« 1, 33-5 (1952) 280 o - — • , and Snitko, 0. Y os "The Effect of the Adsorption of Molecules on the Photoconductivity of Semiconductors c I OJ "Tr In-ta Fiziki 3 AH Ukr SSR, 5 5 65-76 (1951) 28l e — ,-, Snitko, o V and Semenyuchenko, I. M 09 "The Effect of Adsorption of Molecules on the Photoconductivity of Semiconductors « Ho The Kinetics and the Mechanism of the Phenomenon on Cuprous Oxide/ 8 Tr a In-ta Fizikig AN Ukr. SSR., 5 5 77-86 (1951) 282 e — — 9 and Stepko 5 I c P., "A Short Summary of the Study of the Relation Between Electronic Surface States of a Semiconductor and Catalytic Phe- nomena/ 8 Izv, AN SSSR S Ser Fizieheskaya ,, 21 3 201-05 (1957) 283. — -, and Litovchenko, V„ G e5 "Effect of Adsorption of Molecules on trite - -I48- Work Function and the Conductivity of Germanium," Zh. Tekh. Fiz», 28, ktil~f?3 (1958) 28Iio I dem , "The Influence Exerted by the Adsorption of Molecules Upon the Work Function and the Conductivity of Germanium* II » The Kinetics of the Process , " Zh Tekh. Fiz,, 28, No„ 3, h$h-$9 (1958) 285o Terenin, A„ and Solonitzin, Yu„, "Action of Light on the Gas Adsorption by Solids," preprint, Transactions of the Faraday Society , for delivery Septem- ber, 1959 286 e Val'nev, P e Ye , "The Photode sorption and Photodissociation of Molecules Adsorbed by Metals," Zh, Fiz. Khimii, 1308-15 (1956) 28? „ Sarakhov, A. I , "Investigation of Vapor Adsorption on the Quartz „ I, Method of Investigation of Adsorption Isotherms," Izv<> AN SSSR. Otd, Khim N,, 1956 , 5-11 288o , "Investigation of Vapor Adsorption on a Quartz „ II • Investigation of Adsorption Isotherms of Different Vapors," Izv a AN SSSR. 0td o Khlm N 0J> 1956 , 150-57 289 o 9 "Vapor Adsorption on the Surface of Gold," Doklo AN SSSR, 112, I46I1- 66 (1957) 290 o Dubinin, M« M„, Sarakhov, A e lo and Rybikov, G c Io, "Low-Pressure Pore Meter," Zh e Fiz. Khimii,, 32 , II4OU-O6 (1958) 291o Rubinshteyn, A e M c and Afanas l yev, V. A., "Use of the Dynamic Method for Measuring the Adsorption of Vapors to Determine the Size of the Catalyst Surface," Izv„ AN SSSR, 0td o Khim, N. , 1956 , 129U-1030 , 292 Rubinshteyn, A„ M c j Slinkin, A e A e and Afanas'yev, V. A., "Determination of the Size of the Specific Surface of Catalysts Under Dynamic Conditions by Means of an Adsorption Equilibrium," Izv„ AN SSSR, 0td o Khim N , 1957, 32-6 ' ~ " 293 o Rubinshteyn, A e M c $ Afanas'yev, V. A. and Pribytkova, N„ A„, "Determina- tion of the Surface Area of Mixed MgO - C^Oo Catalysts," Izv, AN SSSR. Otd, Khimc N, 3 1956, 1505-07 29h e Rubinshteyn, A e H»j Dashevskiy, M« I« and Pribytkova, N. A„, "Application of Thin Sections in Electron-Microscopy of Catalysts," Bulletin of the A cademy of Sciences, Division of Chemical Science , 1957 s N°° Li, liUl-Jjl+Ii "(English translation) 295© Kaganer, M G G„, "A Method for Determining the Specific Surface in the Unimolecular Adsorption Range," Dokl. AN SSSR , 116, 251-51 (195?) 296o Dobychin, D« P c and Tsellinskaya , T„ F„, "An Accelerated Method of the Adsorption Determination of the Surface Area of Sorbents," Zh„ Fiz a Khimii, 33* No c 1, 20li-07 (1959) -U9- 297© Vasil'yev, B„ N., "An Apparatus for the Determination of Adsorption at High Pressures/' Zh. Fiz„ Khimii, 31, 1498-500 (1957) 298 c , Frumkin, A. N e , "Significance of Electrochemical Methods in the Determination of Surface Properties of Compounds," Surface Chemical Compo unds and Their Role in Adsorption Phenomena (A. V. Kiselev., ed.), Moscow University Press, 1957 5 5^5l (AEC Trans. 3750 (1959 ) ) 299 Rurbatov, L c N., "Dielectric Properties of Surface Hydrates and Adsorbing Layers on Silica Gel and Aerogels of Silica," Surface Chemical Compounds and Their Role in Adsorption_ Phenomena (A, V. Kiselev, ed«), Hdscow University Pres7Tl9^,"lT^^fTAEC^Trans. 3750 (1959)) 300 o lelovich, S. Yu. and Margolis, L. Ya., "Investigation of Gas Adsorption on Manganese Dioxide by the Electrical Conductivity Method," Izv. AN SSSR. Ser. Fizicheskaya, 21, 206-10 (1957) 301 o Zhilenkov, I. V«, "Debye Dispersion of Adsorbed Water at Low Temperatures," Izv a AN SSSR. Otd. Khim. M ej 1957, 232-35 302 o Gol 8 bert, K„ A c and Ponomareva, K. S», "A. A. Zhukhovitskiy, " Zh. Fiz. Khimii, 33, No. 3, 738-39 (March 1959)/ 303 o Vagin, Ye. V. and Zhukhovitskiy, A. A., "Theory of Thermal Separation of Gas Mixtures by the Adsorption Method, 8ti Pokl. AN SSSR, 9k 9 273-76 (19 5k) 30I4-. Zhukhovitskiy, A. A. and Turkel'tanb, N. M., "Apparatus for Continuous Separa- tion of Gaseous Mixtures," USSR Patent No* 107, 8^2 (October 25, 1957) 305o Brodskiy, A. M.j Kalinenko, R« A. and Lavrovskiy, K, P., "Analysis and Separa- tion of Gaseous Hydrocarbons by the Adsorption Method, " Khimiya i Tekhnol. Topliv i Masel, 1956, No. 8, 18-22 306o Idem , ^Application of Adsorption Methods of Analysis and Separation of Hydro- carbon Gases During Investigation of Kinetics, Using Tagged Atoms," Problemy Linetiki i Katallza , Akademiya Nauk SSSR, Insituta Fizicheskoy Khimii, Sovesh- chanie, Moscow, 1956$ £, 399-kOk (Published 1957). 30? « Fedoseyev, P. N., "Adsorption of Sulfur Oxides by Silicates, 18 Zh e Ana lit o Khimii , 13, 123-26 (1958) 308 o Yegorov, N. N c , et al«, "Purification of Gases with Activated Carbon," Removal of Sulphur from Coke-Oven and Oth er Fu el Gases , Moscow, 1950, Ch„ IV, pp. 37-' U7 ~ ~ 309o Step, Kh. Ya., "Adsorption Units for Drying Air," Kislorod, 10, No. 6, 25 (1957) 310, Glebova, L. I e , "The Effect Produced by Heat Production Upon the Dynamics of the Adsorption of Steam," Kislorod, 10, No. 6, 11-18 (1957) 311o Solyankin, L. N., 85 Adsorptive Drying of Oxygen Under Industrial Conditions," Kislorod, 1959* No. 2, 39 -hh -50- 312. Zel'venskiy, Ya. D«, "Adsorption Method for the Removal of Carbon Dioxide from Compressed Gases Which Subsequently Go Through a Cooling Cycle,," USSR Patent No* 110,676 (May 27, 1958) 313o Ishkin, I. P. and Katina, N. F., "Purification of Air from Acetylene and Car- bon Dioxide by Adsorption at Installations Producing Technical Gaseous and Liquid Oxygen," Kislorod , 12, No. 2, 37-38 (March -April 1959) 311u Petukhov, S. S.j Vagin, Ye. V. and Zhukhovitskiy, A„ A c , "Krypton and Xenon ," USSR Patent No. 110,873 (June 2$ 9 1958) 315. Kel'tsev, N. V. and Khalif, A. L., "Periodic Charcoal Adsorption Units with Horizontal Adsorbers," Gazovaya Promyshlennos t 11 , 1958 s No. 7 $ hk~hl 316^ Kel'tsev, N. V., "Drying Gas by Means of a Moving Bed of Adsorbent,," Gazovaya Promyshlennost 8 , 1956 , No. 11, 32-6 317. Idem., "Separation of Acetylene by the Continuous Adsorption Method," Khimiya TTekhnol. Topliv i Mascl , 1956, No. 12, 17-22 3l8» Kel'tsev, N. V.j Khalif, A. L. and Khodanovich, I. Ye„„ "Separation of Butane- Butylene Mixtures," USSR Patent No. 10i|,7ll (January 25 5 1957) 319 « Benedek 5 P.j Szepesy, L and Nad, Z., "Continuous Chromatography (Hyper sorption) on an Experimental Assembly," Gazovaya Promyshlennost" , 2 S 30=8 (1958) 320. Kul'skiy, L. A.j Koganovskiy, A M. and Rybchinskiy, M„ I., "A Counter current Adsorber with a Two-Stage Suspended Layer s n Khim„ Prom-st 11 , 1958,, No. 8 5 h98=99 •5L- CRYSTALLIZATION The importance of crystallization studies and the over-all objectives of the Soviet scientists in this area were succinctly stated by Academician A. V. Shubr&kov at the First Convention on Crystal Growth held in Moscow on 5-10 March 1956. l/ Crystal formation problems are of great interest (importance') in science and technology «, Modern solidstate physics (piezo- and ferroelectricity, ferromagnetism, luminescence , photoelectricity, semi conduction 3 optics of new crystalline media) is closely bound up with the study and use of large uniform crystals , the growing of which demands a many-sided and profound study of crystallization processes « Crystal studies are also very important in biology, in particular in virology. In contemporary metallurgy and in the chemical , ceramic, etc industries , improvements to a large extent depend on a profound study of crystallization processes. N. N. Sheftal, at the same conference , saids The industrial uses of synthetic single crystals have greatly increased in the past 30 years. This has stimulated much theoretical and experimental work on crystal growth. The theory of the ideal perfect , and later that of the ideal imperfect growth of crystals answered many of the most important problems of growth and dissolution mechanisms in crystals* Mew powerful methods of studying crystal surfaces were evolved, such as the electron microscope, field-emission microscope, and various interferometers . PTuorite and quartz in no way inferior to the natural have been grown in the laboratory and many new single crystals of artificial compounds have been grown. Finally, natural diamonds have been successfully synthesized. In spite of these successes we still lack a theory of real crystals, and there is a large divergence between theoretical and practical work on the growth of crystals. 2/ The Soviets engaging in crystallization have made extensive use of Western work as a basis for more rapid advancement of their own studies » Their famil- iarity with Western scientific publications is shown by numerous references to the outstanding theories and publications of Western scientists in the field* In a typical gesture, the Soviet authors insist upon asserting that their Soviet researchers have further developed and extended any work started in the Western world. In 19hl 9 V. D. Kuznetsov reviewed the completed and continuing work on the physics of solids in the various research institutes of the Soviet Union. The . main topics of study were the crystallization of supercooled (crystallizing) liquids, crystal growth and habit, plasticity and strength of ionic crystals, plastic de- formation of polycrystalline solids (metals), brittleness of steels and alloys, physical foundation of metal cutting, and metallic and nonmetallic mono- and poly- crystals. With the exception of an increased emphasis on semiconductor crystals, current studies have been continued on the above or similar topics. 3/ -52- According to A Novikov, "The Institute of Crystallography, Academy of Sciences, USSR 5 is the only institution in the USSR which investigates in detail the structure and physical properties of crystals, does research on phenomena taking place in than, and conducts work pertaining to the industrial application of results obtained in this field." Z. Pinsker is director of the Laboratory of Electronography, which is concerned with investigating semiconductor materials and heat resistant alloys, defining the (surface) structure of crystals, and elucidating the forces of inter- action between atoms in crystals. At this Institute, studies on crystals for scintillation counters are emphasizedo These counters are used in prospecting for nuclear ores and in core sampling in test petroleum wells. Work on crystallized corundum, for instance, rubies, has shown sufficient promise to commence the pro- duction of artificial rubies for watches and other instruments, i.e. jeweled bearings. Quartz for spectrographic prisms and lenses has been artificially grown under the direction of N. N. Sheftalo k/ It is apparent that the Soviet research scientists are encouraged to publish results of their studies that are considered pertinent to continued progress,, Some of the publications, however, are essentially repetitious. While this in- dicates a continuing interest in the field p it also shows the pressure for publishing, For example, Yu. M. Zhvirblyanskiy divulged a method for the crystallization of massecuite from the second syrup of sugar refining (impure molasses). 5/ In 19li9, he and A. K Volobuyeva and D. R. Abragam discussed the kinetics of sucrose crystallization from impure sugar solutions. 6/ In several later reports (1953 and 1955) 9 the same authors presented the information on the same general topic, namely the possibility of obtaining crystalline sucrose by cooling the impure syrup and seeding it with highly dispersed crystallites* 7/ Although many of the Soviet studies are based on Western work and the pressure to publish causes repetition^, it should be stated that the Soviets are devoting themselves to intensive studies in this area,, To provide a more detailed view of Soviet advances in the crystallization field, the follovring discussion is organized under four subject headings? crystal growth, crystal systems, habit modification of crystals, and crystallization apparatus and methods for growing crystals. Crysta l Growth There are presently two main theories of ideal crystal growth. The first is the Kossel-Stranski molecular -kinetic theory of ideal perfect growth; the second is the theory of ideal imperfect dislocation growth. Essentially, the two theories supplement each other, although the rapidly developing dislocation theory relies somewhat on the Kossel-Stranski one for its complex physico -mathematical and structural geometry apparatus. The first theory ignores crystal imperfection and introduces a number of simplifying assumptions in analyzing growth processes. The crystal surface is considered undeformed, and the growth is assumed to occur at very low super saturation. The second theory incorporates initial imperfections mainly as screw dis- locations. The steps, which gradually rise from the crystal faces, being produced by dislocations, remove the need for two-dimensional nuclei and cause the low-index- faces to grow continuously in a spiral fashion. -S3- While this theory implies that the supers a turation at which growth starts in a perfect crystal should be 50 per cent sufficient dislocations present on the faces of a crystal permit growth at 1 per cent supersaturation Sheftal' has stated that the history of an individual crystal can be described in terms of normal development in favorable conditions and complex abnormal develop- ment as influenced by unfavorable conditions due to the action of the medium* From initiation via growth and destruction of a single uniform crystal,, one passes to skeletal and finally to dendritic growth,, At this pointy the medium is incorpo- rated to such an extent that the crystal is not completed^ 2/ The manner in which the physical properties of crystal depend on the growth conditions is determined, in essence, by the same factors that control the shape. The properties depend on the impurities, i.e. on inclusions of the medium, on the stresses caused by unevenly distributed medium inclusions, and on the supersaturation at which growth occurs,, Choosing conditions for growing crystals of a substance with pre-set" physical properties amounts to producing a favorable chemical environ- ment, eliminating harmful impurities, using the best type of stirring, providing uniform material supply to the surfaces, preventing impurities from being incor- porated, and using carefully controlled temperature gradients e 2/ D. S. Kamenetskaya has conducted studies on the effect of impurities on the production of crystallization nuclei in supercooled liquids. 8/ Her work was based on Volmer's theory of crystallization,. This in turn was derived from Gibb's thermodynamic work as extended by Frenkel. 9/ 7. I c Danilov's work, as that of other Soviet and foreign workers, has confirmed this theory . Kamenetskaya ' s results maybe summarized as follows s (1) Crystallization centers form impure liquids at high degrees of supercooling that are determined by the surface tension at the crystal liquid interface. (2) The absence of much supercooling in practice is due to active "insoluble particles and small amounts of surface-active impurities (3) The mechanisms that determine the activity of insoluble and soluble impurities differ: (a) the insoluble impurities act as pre-existing centers, (b) small amounts of soluble impurities materially influence the rate of center formation, which is a consequence of their influence on the surface tension and on the activation energy of center formation, and (c) surface-active additives can conceal the actions of insoluble active particles as the liquid may then crystallize spon- taneously (throughout the volume) at small degrees of supercooling. 10-11+/ Research by K. M. Gorbunova indicates that crystal growth during electrolysis follows laws very similar to those obeyed by metal crystal growth from vapors or by salts from solution. This is true with regard to both the formation of the first nuclei of the new (solid phase) and to the growth of the whole crystal or any of its individual faces. Theory and experiment show that diffusion factors play a large part in the crystal growth mechanism. In the steady state in electro- crystallization, Gorbunov showed that where a single crystal (or a system of crystals not in contact) is growing, the current density (per unit of growing surface) remains constant. 15/ Gorbunova, o S. Popova, A e A. Sutyagina, and Yu. M. Polukarov have demonstrated that regularities in the growth of cathodic metal deposits, either as dense coatings or friable dendritic structures, can be obtained by varying the deposition conditions. Technically useful properties of such crystalline metals such as high hardness, wear resistance, and defined electrical and magnetic properties can be realized. 16/ -51- The terms "physically possible** and' "physically impossible" were first used in relation to the crystal faces by A. V. Shubnikov By the term, "physically impossible., 8 * he referred to the faces of a substance which do not appear, even temporarily, on crystallizing spheres „ 17/ M Ansheles also discussed this subject and stated "„ . .those faces are physically possible (under given conditions) in which the interparticle distances are equal to or less than the greatest distance of effective interaction between crystals and liquid- or gas-phase particles in at least two directions. Faces not corresponding to this condition are physically impossible ." 18/ A. I. Landau has derived equations in partial derivatives that describe the impurity distribution in the melt at any time. The distribution of the impurity in the melt and consequently in the crystal depends primarily on the rate of impurity diffusion in the liquid c Any method of controlling the actual distri- bution of impurity between the melt and the crystal is highly important in both the growth of semiconduction crystals in their subsequent commercial use c 19/ Electron and ion field-emission microscopes (electronic microscope-projector) have become widely used in the USSR and in other areas of the world for physics research . A P. Komar and Yu. N. Talanin have used this technique for studying the effect of two-dimensional crystals transformed to liquids on heating (contam- inants) in contact with other crystal surfaces 8 20/ The device is also valuable for studying certain properties of crystals such as surface migration^ adsorption* crystallization, recrystallization and phase changes Mechanical crystallizers, i«e units in which crystallization is aided by stirring, are now commonly used in large scale chemical industry. Although these crystallizers are widely used, their design is based on extremely simplified assumptions since moving or stirred media have not been extensively studied. L. N. Matusevich studied the crystallization of potassium nitrate and potassium ferrocyanide from water solutions in cooled and stirred vessels He shewed that the mean crystal size decreases smoothly as the stirring speed is increased 5 and that the degree of suoer saturation required for crystallization also falls with ar increased stirring speed* 21/ Scrextf dislocation in the growth of B-methyl-naphthalene from alcoholic solutions and from the melt was studied by M, I. Kozlovskiy His data show that screw dis- locations may be formed as a result of the inclusion of foreign particles during crystal growth,, 22/ In a further study, he observed that spiral growth occurred most frequently from pure solutions at the edges of the crystal regardless of the rate of growth «, 23/ Matusevich also studied the effect of rates of cooling and stirring on the unseeded crystallization of saturated solutions of potassium nitrate and ferro- cyanide o His results showed that the temperatures of initial crystallization were not a function of the rate of cooling if high rates of stirring were maintained. When this is applied to commercial crystallization., it means that more rapid cooling results in more rapid crystallization only if more rapid stirring is con- comitant. 2h/ -55- The kinetics of crystallization of supercooled organic liquids , -viz , piperine. salol, and p-toluidine, were defined by G. L c Mikhnevich and V. P« Xefimova. The number of centers depends on the character of the saturation curves and on the rate of cooling. The presence of particles of active admixtures improves the rate of crystallization. 25/ 26/ Under the usual purification conditions., slowly crystal- lizing organic compounds such as betol, piperine , and aspirin were found to crystal- lize out on' particles of impurities. They contain a crystalline layer of the compound on their surfaces. The kinetics of growth are those of a first order reaction. 27/ The rates of crystallization of potassium aluminum sulfate, copper sulfate, and strontium sulfate were determined by N. A. Figurovskiy and T. A. Komarova. For the first two (highly soluble salts), the rate of crystallization is a second order process which is expressed by the equation 4 Pi / S^t - kX 2 where, ^Pi is the increase in crystal weight, S is the crystal surface, ^t is the time interval, X is the degree of supersaturation and k is a constant. Crystal- lization does not begin spontaneously for strontium sulfate (slightly soluble salt) until a high degree of supersaturation has been achieved. 28/ 29/ N. V. Alyavdin, Sheftal', and Z. I. Frolova have proved that high growth rates for Seignette salt (double tartrate of sodium and potassium) crystals can be obtained by high supersaturation and elevated temperatures. By destroying the tartrate seeds, which cause decomposition of the Seignette salt at elevated temperatures, single crystals weighing almost one kilogram were grown within 63 hours as compared with the old rate of 12 to 13 days. 30/ Five types of crystallization of isomorphic salts from aqueous solutions have been described by S. M. Chirkov a (1) The crystallization path proceeds from the less soluble salt to the more soluble salt independently of the initial com- position of the solution. The salts which are finally crystallized are pure. (2) The direction of crystallization depends on the initial composition. As the crystallization process proceeds, the solution approaches that of a pure solution of one compound. (3) The direction of crystallization depends on the initial composition. As crystallization proceeds, the solution composition approaches that of maximum combined solubility,, (U) The crystallization path is similar to (l) but the compo- sition of the solid phase varies with that of the mother liquor. (5) The crystallization path is similar to (3) but the end composition is different for the two directions of approach. Jl/ -56- The factors affecting the crystallization process,, i.e, crystal growth, were determined by Sheftal' to be the degree of association , the presence of admixtures; the crystallization pressure^ the conditions of equilibrium* and the forms and the solubilities of the crystals. In 1938 5 Sheftal 1 developed a method for growing large sucrose crystals that are heavier than 200 grams by slow cooling over a period of several months „ In this way 5 a very low degree of supersaturation was maintained e He applied his method to the production of large crystals (1<,1| kilogram) of Rocheile salt. This salt was badly needed but was not being produced in the Soviet Union prior to l°39o By 19h6 5 however ^ 75 per cent of the production of Rocheile salt required by the USSR was produced by Sheftal 5 s static method 33/ During his study on the production of large single crystals 9 he found that inhomcgeneities are caused by foreign inclusions 5 temperate changes <> and uneven growth processes 3li/ The study of techniques for ^growing large crystals was continued by S„ K Popov and Sheftal : who developed a process for growing monocrystals in a seeded erystallizer for use in optics and piezoelec tries s and for other purposes,, The erystallizer is imparted a random motion in relation to the crystal,. This is accomplished by reversing the rotation of the erystallizer in a vertical or horizontal plane e The crystals are grown from melts 5 gaseous media ,, or solutions The method is not too dissimilar to the "rocking erystallizer s" used for single crystal production in the Western world c 35/ Interest in piezoelectric crystals in the Soviet Union has led to stadi.es which have culminated in patents for growing crystals,, P c G„ PezdnyakoT arid A„ A, Shternberg grew ammonium phosphate in a pronounced unilateral direction by using a primer seed cut parallel to the edge of the pyramid,, 36/ Another patent of theirs deals with the production of unilaterally growing crystals of ethylenediamine forma te„ Laminar seeds are placed in the pockets of the :rystal carrier in such a manner that only the intersections of the rapidly growing facets are exposed* 37/ Ethylenediamine tartrate crystals were grown by Pozdnyafeor from a solution containing a slight excess of ethylenediamine at a low supersaturation in order to avoid heterogeneities AVrate of growth of 5 to 8 millimeters per day was obtained at U5°C with only 8 to 12° of undercooling „ >'3 Pbzdnyakov has also described the results of growing lithium sulfate and potassium tartrate crystals o By utilizing slow cooling or slow evaporation tc get supersaturated solutions s he obtained crystals that are 65 grams in size for the former salt and 500 grams for the latter 39/ kO/ Diffusion appears to be relatively unimportant as a controlling factor in crystal growth for highly stirred solutions if the solution is sufficiently supei- saturatedo It becomes the dominant force,, however* when the solute has become sufficiently exhausted from the solution over a wide region,, Ye„ A„ Arinshteyn expressed this mathematicallys V(t) = k C n (o 5 t) - C " Equation -..'; where ^ V(t) is the rate of growth at time (t), C is the saturation concentration, n is the order of the process,, and k is theJcineSic coefficient,, Equation can be expressed as a series in powers of t2 bys. * k ((£ - C Q n ) - (2ncfk 2 /rrD)o Cg," 1 (C^- CJ where S is the density of the crystal,, J4I/ -57 - 3$ o' Equation I 2; Do Te " ©vsiyenko has showed that when crystals of galena- are added to solutions of sodium chloride or sodium bromide 9 the super saturation limit of each is uarkedly reduced because of the isomorphous nature of galena with the two salts c Melts of hydroquinone give similar results on metastability and orientation on various iso- morphous materials It 2/ A kinetic study was made by I V» Salli on the growth and the form of a crystal of the new phase that separates from a supersaturated solution* The rate of growth can be expressed by the equation! dq/dt • Iflrffi - (a/rH Fl/x) * (l/r) J] u -T *- —* Equation where,, q is the amount of material diffused through a depleted zone around the crystal in time,, tj D is the diffusion coefficient^- C-CL^the difference in concentration in the solution^ C 9 and at the crystal boundary 5 C5^ r is the radius of the crystal] x is the thickness of the depleted zonej a = 2^Mvc/RT s with#*-~° the surface tension 5 M the molecular weight of the solute 9 and v the molecular volume of the solute The effect of surface tension .j^—j is found to be important only in the first stages of crystal growth,. In quiescent solutions 9 the thickness of the depleted layer ^ x 9 can be considered constant,, Therefore^ the rate of growth can be shown to increase with a decrease in this constant thickness., x s and it passes through a maximum at a given size of crystal nucleus., jijj/ hh/ The linear growth of the crystal boundary was measured by Danilov and V© I© Malkin for phenyl salicylate in the region of slight supercooling , They found the relation between the rate of growth and the supercooling to be exponential© The exponential curves coincided with the theoretical curves h%/ Danilov and A. G© Pomgaybo studied the crystallization of highly purified sodium and potassium in both the presence and absence of their oxides© In each case 5 the maximum undercooling was reduced when even minute amounts of their oxides were presento 1|6/ The importance of impurities to act as crystallization centers was also dramatically shown by Danilov a 0„ D Q Kozachkovskiy 5 and Ya© M e Labkovskiy through experiments with salolo Highly purified salol could be under- cooled almost 100°C o without crystallization unless it was inoculated with salol seed crystals© hi/ Danilov and Kamenetskaya found that the slow cooling of highly purified mercury permitted undercooling by 18 to 21 C o without crystallization, However,, additions of potassium to an amount of o o5 per cent reduced the permis- sible supercooling by 7°to 9 C o 12/ With a co-worker s Yu A„ Krishtal 5 Danilov demonstrated that the crystal- lization of an undercooled liquid can either be caused by extraneous impurities acting as crystallization centers or by spontaneous activity© This., of course 9 is dependent on the methods used to purify a substance Three typical groups of substances can be distinguished as follows s (1) Salol represents Group I© It can be totally deactivated and then will not crystallize at any temperature without inoculation. (2) Ortho-chloronitrobenzene is a representative of Group II© When it is carefully purified and deactivated,, it shows first crystallization centers at 20°C©- ~58~ undercooling and cannot be under cooled more than T7 C o under any conditions. This represents a spontaneous crystallization limit* Piperine is an example of Group III<> This group must be cooled very slowlyj otherwise it solidifies like a ,8 glass.» J48/ W Danilov and Kamenetskaya ' s experiments on crystallization of azobenzene showed that undercooling before spontaneous crystallization could be markedly increased by the presence of soluble impurities s such as alcohol,, 10/ Working with D. Ovsiyenko 5 Danilov extended this series of studies to the solidification of metals «, In molten bismuth and lead 5 the presence of their respective oxides iecreased the limits of me ta stability . 50/ Particles of insoluble materials in the presence of undercooled liquids can affect the degree of such undercooling B Danilov and Ovsivenko found that hydro-- quinone could sustain l5°to 20°C. of under cooling <> However,, the undercooling was only 1.5'°to 2.0°C. in the presence of crystals of calcite c 51/ In this same line of thought, Danilov and co-workers studied the formation oialpha-salol on rock salt particles. When alpha-salol is highly purified ? it can withstand almost any degree of undercooling without the appearance of crystallization centers c In the presence of sodium chloride particles <, crystallization centers appear- in slpha-salol with a reasonable degree of undercooling e 52./ Do A e Petrov found the formation of a solid solution from a liquid solution involves two processes* namely the formation of new crystals and the alteration of the composition of the previous crystals. If the diffusion within the solid is very slow., the second process can be neglected and solidification t akes place as if the solid phase was continuously being removed from the svstem. In this case* crystallization ends either at the temperature of the lower melting component or at the eutectic temperature. 53/ Inter crystalline liquation was studied by Petrov and L c A„ Raykovskaya in aluminum alloys by a method of microhardness These alloys ranged from to 16 per cent magnesium and to 10 per cent antimony,, The hardness measurements were used to determine the degree of segregation in the alloy. The results proved that there was free diffusion in the liquid and no diffusion in the solid. fxh/ The utilization of these experimental studies by Petrov and A. A„ Bukhanova shows that greater homogeneity of metallic crystals from melts can be obtained by lowering extrusion velocity, improving intermixing in the melt,, quickly cooling extended specimens 9 and avoiding a minimum of overheating in the melt. $$/ When mixtures of two or more components are crystallized 5 the additives are always redistributed between the liquid and solid phases. In non-equilibrium crystallizations 9 this redistribution causes macro- and micro-unevenness in additive distribution. Any large-scale unevenness is caused by incomplete liquid phase diffusion and appears by the liquid being gradually enriched in impurities that lower the melting point. These conclusions were based on studies of copper- aluminum, copper~zinc 5 tin-antimony 5 and aluminum-copper alloys made by Petrov and B. A. Kolachev. %&f Ye, Mo Savitskiy, V« F. Terekhova and A. ¥ e Khlopov have studied "fee chromium re crystallization diagram,. Electrolytic chromium tempered at 1300°C o in vacuo and at l500°Co in hydrogen, with a volume reduction by deformation o'f"2»5 to J4.O per cent, was studied photomicrographically, by X-ray spectrography, and microhardness determinations o Chromium recrystallization took place by simple crystal growth at the higher temperature and lower degree of deformation. However 5 at high deformations, it took place by formation and growth of new crystals „ 57/ The recrystallization of titanium and its alloys was investigated by Savitskiy, Mo A« Tylkina, and A. N Turanskaya. They found that the recrystallization diagram can be divided into two parts These two parts are the temperature regions where the e^ and /& phases of titanium are stable e "During the rolling of titanium, no recrystallization takes place e Recrystallization may be achieved by subsequent tempering or by further hot-working „ 58/ The mechanical properties of titanium and its alloys were also determined by Savitskiy, Tylkina, and I c A e Tsyganova e They also constructed a recrystallization diagram for molybdenum from experi- mental data* 60/ N A„ Figurovskiy and T 8 A. Komarova found that the growth of crystals can be considered a free radical process in view of the chain mechanism and the crystal- lization process e The active centers where crystal growth occurs have a higher energy level than the other parts of the crystal surface Separation of the solid phase from the solution begins at the active centers and is accompanied by the destruction of active centers and the simultaneous development of new ones c Potassium chloride crystallization has been used to study the above hypothesis It has been shown that the rate of salt crystallization depends on the nature of the salt, the degree of supersaturation, the temperature, the impurities, and other factors such as the size of the vesselo The crystallization rate can be expressed by the temperature coefficient K T s VJL . ¥ (T * 10)-V_ wherein, (T * 10) and Vm are the crystallization rates at temperature and T, An increase in temperature increases K ♦ 6i/ According to Danilov and Malkin s the growth of a crystal is accompanied by the fluctuation formation on its faces of two-dimensional nuclei and the sub- sequent spreading of these nuclei along the entire face of the crystal* If it is assumed that the nuclei spread along the entire face during a time that is short in comparison with the time of formation of new nuclei on the face, the linear speed of the crystals' growth is determined by the speed of origin of the two-dimensional nucleio This theory may be expressed mathematically by the formula z V - k ie -k 2 /T e - k 3 / T^T where, V is the linear speed of growth 3 T is the absolute tempera turej T is the superGoolingj kg is a constant denoting the energy of activation during the change of the molecule from liquid to solid,, 2 k ^ff? FI m -60- in which p is the boundary tension on the edge of the tiro -dimensional nucleus; F is a unit of surface on which is distributed a monomolecular layer of one mole of substance ^ T is the melting point 5 and k is the Bcizmarm constant „ The first exponential in feis equation deals with the mobility of the particles and decreases with increasing supercooling,, The second exponential deals with the mechanism of crystal growth and increases with supercooling. Small supercooling was used on highly purified salol 5 and the theory as presented was experimentally confirmed „ \\$/ A„ T Grigor'yev has presented several excellent mathematical and theoretical papers on crystallization in binary and ternary systems s (1) The equation of the line of crystallization of the binary chemical compound in a binary systems; (2) The equation of the surface of crystallization of this compound j 2nd (3) The equation for the surfaces of crystallization of the ternary chemical compoundo 62 / 63/ A new method for determining the structural importance of the faces of crystals was reported by 0, M„- Ansheles. The method is based on the Kossel-Stranski theory of the growth of crystals « This simple- solution assumes that the greatest distances are known over which the particles of the crystal interact practically with the particles of the liquid or gaseous phase The theoretical part derives assemblies of physically possible crystal forms for simple, doubly idealized cases e In the practical part 5 the mechanism of a diamond crystal s growth is presented and the form of growth is derived 6k/ The absence of a lower boundary of miscibility is related to the formation of homogeneous mixed crystals that s from the point of view of thermodynamics. ea'£ be regarded as one phase A formula was derived thermodynamically for such crystals by A, N. KirgintseVo This formula relates the coefficient of equilibrium crystallization D 5 with the activity of the micro- and macroelements in their saturated solutions and with the concentration of the macroelement in the mother liquor Experimental data from the literature was used to examine the systems lanthanum fluoride - radium fluoride^ lanthanum fluoride - thorium fluoride ^ and ammonium iodide » lead iodide 5 in detail. These systems confirm qualitatively the derived equations „ 6$/ G. G e Lemmleyn found the closing -up of a crack in a crystal by a saturated solution occurs spontaneously under isothermal conditions c This is due to the tendency of the crystal-solution capillary system,, which has sn excess surface per volume unit of the cracky to establish an energy equilibrium The theory is developed to show that every concentration in a solution corresponds to a def inite critical size of crystal particles that can exist in an equilibrium with that solution. 66/ V. M. Kravchenko has reported that three important and organically, very closely interrelated trends can be differentiated in the studies of the physical- chemical analysis of the equilibrium (liquid-crystalline) systems of various substances s -61= (1) Topology., or qualitative study of the general geometric properties of the equilibrium-system diagram^ (2) Metrics,, i.e. quantitative study of the relationship between the elements of the diagram itself and the parameters characterizing the chemical system occurring in the systemj (3) The science of the casual relationship between the topological and metrical characteristics of the diagram of the equilibrium of phases and the structure and properties of the system components «, These trends are treated through a series of developments which utilize an ideal phase-equilibrium diagram in a' study of metallic., inorganic., and in- organic-organic systems o This development results in the conclusion that 5 for studying real crystal systems s ideal temperature-composition diagrams for crystallizing systems are as important as the concept of the ideal gas. 67/ A method was proposed by A. N Q Idapunov and Ye P<> Kholmogortseva for determining the average growth rate of hydrargillite particles suspended in large numbers in a supersaturated aluminate solution., as a result of growth of the crystal faces. An equation was developed for determining the linear growth of the crystal faces to define total growth rate. The method may be applicable to other substances growing in supersaturated solutions,, 68/ A K. Skryabin mathematically and theoretically derived equations for the kinetics of the crystallization of solutions and melts with and without consid- eration of the medium's supersaturation and the gradient of concentration* The theoretically computed curves of the kinetics of crystallization for solutions and melts coincide with actual experimental data for supersaturated potash alum solution and for melts of zinc 5 lead 5 tin 5 and aluminum,, 6g/ The Soviet work on crystal growth is extensive and important. It is obvious^ however $ that much of the research is carried out to augment and supplement the need for practical application,. Theoretical work on crystal growth thus tends to lag behind practical studies. Crystals Systems Ye„ S Makarov has collected,, collated., and presented extensive data on the crystal chemistry of the actinide elements „ The arrangements of atoms in crystals of actinides and their simplest compounds (chiefly thorium,, uranium 5 plutonium and neptunium) are shown, A table is presented that shows the analogy between the crystal structure relationships of the actinides and the lanthanides and elements of the IVa 5 Va 3 and Via subgroups of the periodic system,, 70/ Of the 117 references used by Makarov in compiling his book 5 only eight are Soviet „ 71/ Once again 5 evidence is given of the present heavy dependence of the Soviets on Western work for the funadamental chemistry of the important nuclear fuel elements . A series of good studies was conducted by G. I„ Gorshteyn and N. I. Silant'yeva on the equilibrium distribution of isomorphic and isodimorphic components for various systems t =62= FeSO -CoSO -H 0, MSB ~FeS0 - H O s and NiSo ~MgS£ ~H o h U 2 h U 2 U 42 The coefficient of distribution,, Dequil (iron,, cobalt) « is ideal at 20 c C o and eqta ■ to lo20„ Other values vary 5 depending upon the ranges of concentration,, A system of Co(N03)2"Ni(N03)2»H2 at 20 ° c «> was also studied*, and it was found to give solids of different crystal structures^ since the two salts are not isomorphous 72-7J4, Gorshteyn and Silant'yeva continued for another system., copper ammonium sulf arte -zinc ammonium sulfate-water-at 20°C„ utilizing radioactive isotopes of zinc (65) and copper (6k) to determine the distribution coefficient,, 75/ The above important work resulted in Gorshteyn "s development of the following conclusions., which have a bearing on the practical problems arising in connection with the industrial purification of inorganic salts „ The study of the coefficient of distribution showed that it is nearly constant at any micro- or macroconcentration of the salts studied., as long as a solid phase with a definite structure remains constant,, The experimentally established relations of the linear law of distri- bution are of considerable practical importance in problems relative to the frac- tionation of salts 9 specifically salts of rare-earth elements and other rare elements. Most of the work was developed by use of radioactive isotopes „ 76/ The preparation of high quality potash fertilizers from the Carpathian mines is difficult because of the multimineral nature of the raw material--sylvine 5 kainite^, langbeinite 5 picromerite and polyhalite A method has been developed by M„ Ye Pozin and M B I Muratova for conversion of these minerals into potash fertilizers A study of the crystallization of potassium chloride from kainite liquors showed that the quality of potassium chloride from kainite liquors showed that 'che quality of potassium chloride is independent of the time of cooling (below \\$ minutes) and the temperature (above 30°C o ) If the ratio of syivite to kainite in the original ore is less than o»3 5 good quality potassium chloride can be obtained by crystallization © 77/ ,78/ Ya c G« Goroshchenko has investigated the mutual solubility of the aibbium_ oxide « sulfur trioxide <= water system at 20°C„ for a range of sulfur trioxide from to 77 per cento Two niobium sulfates were prepared— >Nb Gj SO. and Nb^O.. (SO; ) i both are white solids^ crystallizing either in needles or pseudo=>cubes<, J9J 4 TEe crystal structure of the double salts of niobium and ammonium sulfate was also investi- gated* The three following salts were obtained s NH, NbO 30 > ') ~ „ (NHi -NB.OvSO U kk ko 2 ■ U and (NH^)3NB(S0^)^ e All are crystalline solids but decompose in water solutions „ Similarly,? the double salts of tantalum and ammonium sulfate were studied „ Twc salts were obtained,. Both are crystalline solids but decompose in water 8 L In the presence of various amounts of sodium hydroxide «, curves were deter- mined by Mo I. Ravich and F Q Ya„ Borovaya for the phase diagrams of sodium s ilfate • sodium chloride = water for pressures up to 200 atmospheres and temperatures b 600°Co 82/ -63- K Ye Mironov,, Z N„ Pronina and S G A„ Tokareva have made complete investi- gation of the phase diagrams of hydrogen peroxide - sodium per chlorate - water and hydrogen peroxide - lithium perchlorate - water No peroxyhydrates of either sodium or lithium perchlorates were obtainedj however., in the presence of hydrogen peroxides,, various hydrates of each perchlorate were obtainedo _83/ Ye K„ Akopov and A„ G Bergman found the system sodium chloride - potassium chloride - lithium sulfate to be a stable section of the complex mutual system c It is a simple triple system with an eutectic point at i|.26 C 6 and composition 2ii per cent potassium chloride^ 17 per cent sodium chloride., and $9 per cent lithium sulfate • 8h/ The liquidus lithium fluoride and strontium fluoride were studied by Ye, I Banashek and Berhman The eutectic point was at 76l C o and 33°5 per cent strontium fluoride e For the chloride system^ the eutectic point was t l487°C e and 5U per cent strontium chloride 85/ The system hydrogen fluoride - iodine oxide - water was studied by N S„ Nikolayev and Yu© A Buslayev n They observed the solid phases 0°C o were iodic acid and the double acid 2HX0-j,3HF 5 a new compound,, Compounds of the combined iodine- fluorine -oxide were not found at any concentration of hydrofluoric acid 86/ No K Voskresenskaya and S„ I Berul found that the equilibrium in the system sodium nitrite - potassium nitrite - water at 70°C shows a solid solution of sodium nitrite -potassium nitrite „ At the eutectic point,, this solution is more than 20 per cent potassium nitrite 87/ While many other crystal systems were studied by Soviet scientists^ those mentioned above show the wide diversity of such studies The practical significance of the referenced systems is important to the expanding the Soviet chemical and metallurgical industries „ Habi t_M odification of Crystals The presence of o ganic impurities in the mother liquor., even at low con- centrations ,> materially influences crystal properties 3 habits of crystals 9 and crystallization o The interactions between impurities and growing crystal faces has received less study than has changes in habit Such effects have important impact in crystallization,, Ye c N Slavnova used spectrophotometric methods to elucidate the states of impurities (methylene blue) in barium and lead nitrate crystals* Lead nitrate takes up the dye mainly in the molecular state This ±s 9 solid solutions of a special type are formed on the cube face growth pyramids However 3 barium nitrate is entered by the dye as suhmicroscopic crystallites 5 giving a micro- heterogeneous system,, When there are structural similarities between the com- ponents,,, the way in which impurities such as methylene blue enter the crystals is determined by the surface adsorption properties 9 the state of the impurity in the mother°liquor 5 and the tendency of the impurity to give adsorbed particles „ 88/ Both crystals from metals and alloys and crystals from inorganic salts 5 viz cadmium iodide s potassium perchlorate and others 3 under the presence of impurities in the melt 3 were studied by D, A D Petrov and B, A„ Kolachev Q They concluded that when mixtures of two or more components are crystallized ^ the additives (impurities) are redistributed between the liquid and solid phases ~6h~ This redistribution in non-equilibrium crystallizations causes macro- and micro- unevenness leads to two types of distributions, (l) layered distribution, and (2) substructures. 56/ The growth rate and shape of Rochelle salt (pure and plus borax) and potassium and ammonium aluminum alums (with added sodium carbonate) were investigated by A. V. Belyustin and V c F. Dvoryankin. They found the relative face growth rates can change with supersaturation in cases of the alums and pass through maxima and minima in Rochelle salt. The impurities used did not change the relative growth rates as functions of supersaturation but did alter the shape of the crystals. 89/ Clearly developed facial steps starting from the edges and corners and extending to the face centers are caused because the larger growth rates at corners and edges are much larger than on the faces. D. D. Saratovkin has dis- cussed this type of growth in detail. These crystal forms are termed "skeletal." 90/ Ansheles has asserted the converse effect can also be observed,, In other words, the face center layer growth rates can be much higher than the edge and corner oneso. In this case, the faces becoire convex and take on antiskeletal shapes. 91/ A. F. Gorodetskiy and Saratovkin have made studies on cadmium iodide crystals. They stated, M Anti-skeletal growth forms on crystals, which arise from spiral growth on screw dislocations, can pass over to peculiar dendritic growth forms such as are also obtainable from skeletal forms. We term these layered dendrites, le&t, branching crystals with layered growth." Impurities play a strong part in producing large groups of screw dislocations, e.g., lead iodide growing in the presence of cadmium iodide. £2/ G. G. Lemmleyn and Ye. D. Dukova have proved naphthalene and p-toluidine, sublimed from a vapor phase, show spiral growths in the early stages of nucleation and crystallization, starting from the re-entrant angles of dendritic forms. Such dendrites are developed with variable types of branching. 93/ Other work of these two on growing a crystal of p-toluidine proved that the growth of elementary lasers or: the crystal face took place through the formation of a mobile adsorbed layer. 9h/ Lfjimnleyn considered the properties of the boundary surfaces between crystals and Solutions (or vapor) under conditions of equilibrium for both "positive" and "negative" crystals.. The latter were crystals with closed cavities filled with liquid. 66/ He used hexamethylenetetramine in his experiments and showed that the ^negative' 9 crystals which are formed in saturated solutions over geological periods can be understood as nearly ideal equilibrium forms. 95/ A rather complete discussion of dendritic growth during crystallization, both of metals and of organic and inorganic compounds, has been presented by D. D. Saratovkin. Saratovkin' s observations and conclusions are based on studies performed on crystallization with a stereoscopic microscope. The explanation of dendritic crystallization must be sought in an understanding of the role of impurities that are always present in crystallizing systems. 90/ A high per- centage of Saratovkin* s 127 references refer to Soviet studies. This shows the great interest and competence of Soviet scientists in this phase of crystallization, expecially as applied to metal casting and solidification which dates back to the famous work of Chernov «, £0/ -65- V„ le Malkin observed that the transition to an acicular shape ■crccnrs when the rate of growth of a crystal of salol increases,, When undercooling is decreased., the rate of growth decreases 9 and the growth of acicular crystals is replaced by the growth of crystals of regular shape This transition was also observed in an ingot of crystallizing tixu 96/ This phenomenon was mathematically studied by G P<, Ivansov a He found that., under a given set of conditions, the product of the rate of crystal growth of acicular crystals and the radius of the tip of the crystal is a constant* 97/ The dislocation process that occurs during crystallization is not an accidental phenomenon,, V. L. Indenbonn found it is brought about by the irregular distribution of the temperature in a growing crystal „ 9§/ No Go Zaytseva and A„ M c Smirnova studied the rate of crystallization of hydrated tricalcium a laminate in the presence of surface-active substances, such as saponin and lignosulfonates Small additions of surface-active substances in- creased the rate of crystal growth and repressed the speed of nuclei formations,, 99/ Ye a So Solenr'yeva and Ie e Ye. Segalova stressed the importance of the -structure of tricalcium aluiTiinate since this compound forms part of all Portland cements They found tfae induction period of structure formation (initial set) in which newly formed crystals appear is very shorto The maximum stability of the crystal structure is reached when the anhydrous alumina te becones completely hydrated 100/ The stabilities of supersaturated solutions of barium iodate and lead iodide were studied by M. V. Tobin and S„ I„ Krasnovao The values of the maximum relative super saturation that can be attained without bringing about spontaneous crystal- lization were determinedo Additions of fuchsin, eosin, and atebrin to th® super- saturated solutions showed that the maximum relative super saturation of solutions of barium iodate and lead iodide was increased- by adsorption of these materials on the solid crystalline phase 101/ V» A a Mokiyevskiy studied epsom salt in the presence of borax, aniline, and methylene blue» The changes in the crystal form and the rate of crystallization were brought about by adsorption of the two organics on the growing crystal faces Q 102/ N« P c Alekseyeva found that during tile crystallization of potassium alum from solutions containing safranine, only surfaces grew on the crystals, while rhombododecahedron and octahedron surfaces were suppressed c 103/ The effect of xylan, dextrine, hemi celluloses, and resinous substances on the stabilization of calcium sulfate solutions was investigated by I e I e Korol'kov and Z A, Tyagunova All of these were effective in preventing precipitation of calcium sulfate and, of them, xylan was the most effective IOJ4/ So V Avakyan and N» F» Lashko studied, by microscopic means, the change in crystallization of the eutectic of potassium chloride and potassium dichromate in the presence of surface -active substances, such as agar-agar and sodium sulphonate When agar-agar was used, the solution viscosity was increased and the crystal size of each component was reduced They observed that sodium sulphonate does not change the viscosity of the solution, but it does decrease the size of the potas- sium chloride crystals » All tested surface active substances influence the process of eutic crystallization by shifting the eutectic point 105/ -66- Crystallization Apparatus and Methods for Growing of Crystals The optical glasses widely used in instruments have -a major shortcoming in that they have low transparency outside the visible region. The use fnl -wave length regions of the most common optical glasses are narrow (from about 0.33 to 2 microns) and therefore cannot be used in the ultraviolet and infrared regions. These shortcomings are especially acute in instruments below 0„2 micron. Only three materials have high constant transmissions in the short ultraviolet, i.e., the fluorides of sodium, lithium, and calcium. Of these, lithium fluoride has the most valuable combination of optical and mechanical properties for use in an optical material. Fluorite (calcium fluoride) has a high and uniform trans- mission over a wide wave length range of from 0.125 to 9<>5 or 10 microns in the infrared. Because of the scarcity of natural fluorite crystals of optical quality, I. 7. Stepanov and P. P. Feofilov have developed and described a vacuum setup for growing fluorite at temperatures of 800° to l500°C o Their method has been industrially adopted, and many optical components in the current instruments now are being prepared from artificial fluorite. 106/ M. A. Vasil'yeva has shown that lithium fluoride crystals are one of the best optical materials for use in vacuum spectrography of the far ultraviolet (below 250 millimicrons)* They are also stable to atmospheric attack, very stable thermally, and have a degree of hardness only slightly inferior to that of fluorite. An industrial methof for the vacuum growth of lithium fluoride crystals in graphite crucibles has been described by Vasil'yeva . 107/ Valuable optical crystals have been industrially produced by this method© Scintillation counters have been widely used for recording nuclear radiations and for studying the emissions produced by the operation of various accelerators,, The scintillator (crystalline, plastics, or liquid) is important, since this trans- forms the invisible nuclear radiation into a visible one. The transformation occurs when" the radiation interacts with matter. Both organic and inorganic crystals, e^g., lithium bromide, cesium iodide, cadmium tungstate, etc., have been used as scintillators. L. M. Belyayev, B. V. Vitovskiy, and G. F. frobrzharskiy have described methods for growing both organic and inorganic scintillators. 108/ Crystal scintillators have been used in scintillation counters for various purposes. The use of these counters has enabled Soviet physicists to solve completely new problems and to develop a new method of detecting nuclear radiations. 10 9/ 110,/ The quality of semiconductor crystals must be uniform and predictable. The electrical properties of semiconductors are determined by the nature, contents, and distributions of impurities present or deliberately introduced and also by crystal structure perfection. Grain boundaries cause uncontrollable changes in the electrical properties, thus disturbing the electronic processes. The semi- conducting materials must therefore be prepared from single crystals. Petrov and V. S. Zemskov have studied the growth of single crystals of germanium with uniform longitudinal impurity distributions of radioactive indium. They achieved this uniform distribution by melt crystallization with a constant feed into the melt. 130./ -67- Mica is a valuable strategic raw material for insulators, K. V„ Kapralov., In. V. Koritskiy, N. N. Sheftal 1 , I. I. Yamzin 5 and M. S. Lsyzerzon have discussed methods of growing and using large synthetic mica crystals, The synthetic mica- based ceramics are exceptionally resistant to thermal shocfe and are useful in equipment subject to variable heat loadings in gas turbine and jet engines and as coatings in the exhausts of supersonic jet aircraft,, 112/ 113/ New piezoelectric materials are needed for various uses© Sorbitol hexa acetate has been shown -to furnish good piezoelectric crystal plates for frequency stabil- ization. I. S. Rez and L. I. Tsinober have shown that it is possible to produce commercially single -crystal sorbitol hexaacetate from 96 per cent ethyl alcohol solutions.. It should be noted 5 however s that the crystals are extremely sensitive to temperature variations and other disturbances during growth. Ill;/ Synthetic quartz crystals have been experimentally grown by V. P. &rtuzov and L. V. Bryatov. They used experimental techniques developed by Western scientists/ UOO°C. and 1000-2000 atmospheres. Single-crystal seed plates were suspended at the top of the autoclave and broken pieces of unsuitable quartz were suspended at the bottom. 115V Crystals of barium titanate and strontium titanate (and mixtures of the two) have been grown from solutions in fused salts by N. S„ Novosil'tsev s A. L» Khodakov 5 M» L. Sholokhovich^ Ye. G« Fesenko^ and 0. P. Kramarov. These crystals can" be grown best from molten potassium fluoride. The dielectric and ferroelectric properties of each crystalline compound are strongly dependent on their heat- treatment. 116/ Ya. V. Grechnyy has investigated the dependence of the probability of the nuclei formation of each phase upon the concentration of the liquid solution for the following two component organic systems % camphor - benzoic acid:; camphor - naphthalene 1 camphor - ortho^ehloronitrobenzenej camphor » paradibromo benzene.. These substances have a tendency towards supercooling. It is concluded from the data that pure components have a minimum tendency towards supercooling s and that the tendency of the melt to supercool is further increased as its composition is removed from that of a pure component. 11?/ B. D. Melnik has shown that salts can be subdivided into two groups based on solubility changes with the temperatures (1) The solubility first rises with the tempera ture 5 then drops to practically zero at some temperature with the formation of either anhydrous salts or salts containing only a little water of crystallization 9 e.g. 5 the sulfates of sodium 5 potassium., magnesium 9 manganese., and nickel* (2) The solubility increases with the tempera ture 5 e.g. 5 most halide salts and ammonium compounds. An elevated tem- perature improves crystallization separation techniques,,. Commercial methods using these principles are described. 118/ In the crystallization of sugar from its aqueous solutions 5 M. B. Yarmolinskiy found that the amount of crystals increases with the super saturation coefficient. Stirring a -supersaturated solution of sugar promotes the formation of seed crystals and thus improves the fineness of the granulated product. 119/ -68- A, Mircsv and K. Sandera have conducted studies on crystallization and product centrifugation of sugar from massecuite in the presence of added salts. They found in a plant-scale experiment that sodium sulfite and calcium chloride improved crystallization,, reduced the viscosity of intra crystalline molasses, and improved centrifugation o Calcium nitrate and aluminum sulfate gave poor results. 120/ The effect of ultrasonics of the kinetics of crystallization on thymol was studied by A. P, Kapustin, It was shown that ultrasonics produced w ingots w which are more uniform and which are composed of smaller crysxals. Ultrasonics (720 kilocycles/second) modified the character of eutectic and ^orthotropic* crystal- lization, i c e« 5 growth perpendicular to the plane of formation of crystals. It also suppressed columnar structures,, 121/ The crystallization of benzophenone (I), o~chloronitrobenzene (II) $ thymoTT III ) , piperonal (IV), salol (V), ammonium chloride (VI), and condensed milk (VII ) in the presence of ultrasonics was observed with a polarization microscope equipped with a camera. In the case of the first group (I, III, IV) the sound caused a splitting -off of newly formed crystallites, directly proportional to the intensity of the sound. In the second group (II, V, VI, VII ) 9 ultrasound caused the breaking of growing crystallites, which served as new centers of crystallization. In both groups the rate of crystallization "was several hundred times that found under ordinary conditions. 122/ Kapustln also has studied the effect of ultrasound in the range of 720 kilo- cycles to 6 megacycles per second on the rate of crystallization of solutions and alloys. The increase in the rate was due to the formation of a larger number of crystallization centers. The rate was increased by a factor of one hundred. The ultrasound waves are effective only if the energy reaches a certain level. No further effect is observed above this limiting' level, 123/ Alum crystals were grown by Kapustln and V. Ye. Kavalyunayte in identical experiments. One was grown with no ultrasound aw awn with the application of an ultrasonic field of 2 megacycles per s&»xwl,and. intensity of 0.2 watts per square centimeter. The linear ""diriMxisions of the crystals grew at double the rate when the ultrasound isas "applied. 12lt/ The term ^taxturi® 9 ' can be used to describe a certain preferred orientation of crystals' in a" crystal aggregate. Interest in texture is important since the physical properties' of a crystalline substance depend not only upon the internal lattice atomic arrangement but also upon the size of the individual crystal- lites and their orientation. By using ultrasonics, Kapustln was able to. obtain a special texture in molten potass, a odium tartrate in 'the form of regularly arranged planes, subject to the frequency of the ultrasound. 12$/ No To Gudtsov has observed 'the effect of ultrasound upon the phenomenon of orthotroplsm or organic substances. The macro structure of a crystalline aggregate is characterized by the presence of sev eral zones of varied structure. The external zone consists of acicular crystals, in which the direction of growth is perpendicular to the walls of the mold. In metals, parallel fiber crystal orientation leads to weakened loads and sometimes to disintegration (or deep crevices) during rolling. The complete elimination or minimization of acicular crystals was achieved in organic substances by applying ultrasound. Thus, the process may be used in casting techniques to obtain a more uniform, fine crystalline structure. 126/ 7- Many investigators have sought new methods for the control of processes in- volving phase changes. Of these methods ultrasound has been shown to increase the rate of crystallization and to produce finer crystal aggregate structures* In a study made by I, G, Polototskiy, T. Ya„ Beniyeva, and Z, L, Khodov, ultra- sound was applied to a melt of ortho-chlorobenzene and to molten zinc, cadmium, and tin. It was proved that centers of crystallization take place in the nodes of the standing ultrasonic waves and in finely dispersed admixtures , With these increased numbers of crystallization centers, fine aggregates of crystals, i,e,, fine grained metal structures., were obtained,, 127/ This phenomenon is of great practical importance , The formation' of crystals in a supercooled liquid may be forced or ••spontaneous, Ortho-chloronitrophenol. was studied by Kapustin to show that spontaneous crystal- lization could take place in highly purified samples at a supercooling of 18 G, Under the influence of ultrasound, the emergence of the first crystallization center was highly accelerated,, 128/ Various theories have been advanced on the increased rate of crystallization under the influence of ultrasonics. B. V, Vitovskiy states that the use of sonic vibrations removes the layer of depleted solution adhering to the face of a crystal and exposes the crystal face to fresh supersaturated solution. Thus, the growth of the crystal face is increased, 129/ An apparatus was designed and built according to Verneuil's technique for growth of artificial rubies. This apparatus was used by D e A. Petrov and Yu M„ Shashkov to grow silicon crystals e 130/ A new type of crystallizer for naphthalene fractions was designed by V. Ye, Privalov and has been put into commercial operation. Essentially, it consists of tubes, which can either be cooled by cold water or heated by steam,, The hot naphthalene fractions are put into the tubes, crystallized by cooling and removed by heating. Production of this type of tube crystallizer is much higher than that of drum coolers, 13 l/ The formulas for designing drum and mechanical crystallizers were presented by V, M, Tamarin and have met commercial requirements, ' 132/ L, N, Matusevich has developed a mechanical laboratory crystallizer to determine the effect of stirring intensity on the process of crystallization and the physical phenomena connected therewith. Investigations on its use have shown its value in laboratory studies, 133/ As early as 19 hi $ it was observed that a considerable increase in the velocity of" 'crystal orientation was achieved under the influence of ionizing radiation, M, L, Bookin and A, A, Semerchan thoroughly investigated this phenom- enon and showed that, under the action of electron radiation, aluminum foil re- acted with the oxygen of the sir to give aluminum oxide crystals. The size of the crystals produced depended on the dose of irradiation. It is postulated that this process can be utilized for the production of inexpensive tools of high quality from aluminum oxide for metal cutting, 13^/ Electric (electronic) processes in semiconductors depend very strongly on negligible amounts of impurities and structural defects. Fractional recrystal- lization (zone refining) is one method of obtaining pure germanium and silicon. However, since diffusion proceeds slowly in the solid phase, the impurities vary as the ingot grows in the melt. By continuously supplying melt for special =70- purposes, D. A. Petrov and B. A. Kolachev showed the same result can be accom- plished as in the pulling process. Crystals can be obtained of a constant composition along the length of the solid. In order to estimate the effective- ness of purification a distribution coefficient, k, is used: k = c /c m s' m where, c is the concentration of impurities in the solid and c in the melt. If k is constant, then one obtains: 7 = kx Q (l - m^- 1 where, y is the impurity content in the growing crystal on the crystalling front, x is the initial melt composition, and m s is the mass of the solid ingot already formed from the melt. Experimental results on various metals, including germanium and silicon, have shown the value of the technique for purification to allowable tolerances for semiconductors. 135/ F* M„ Kutsakov has devoted a study to inducing crystallization in chemical reactions by rubbing. Eleven different solutions, to which appropriate precip- itating solutions were added, were placed in test tubes or on plates of various materials. A variety of materials was used to rub the solution containing materials. The rate of precipitation (crystallization) was increased by this technique. 136/ From the references reviewed it can be concluded thats (1) The Soviet research uses standard techniques; (2) The investigations lead to steady progress and development of practical apparatus and methods; (3) No- outstanding results were reported, which were not already available to the Western world; (k) Soviet authors write as if each paper (report) presents new outstanding results. (This may be due to awkward translations.) -71- E. REFERENCES — CRYSTALLIZATION 1. Shubnikov, A. V. , "Foreword,," Reports at the First Conference on Crystal Growth, 5-10 March 1956, 3 2. Sheftal, N. M., "Real Crystal Formation," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 5-25 " " -— 3. Kuznetov, V. L e , "Work on the Physics of Solids in the USSR," J . Phys , (USSR) , 5 5 299-317 (19UD Uo Novikov, A., "Investigators of Crystals," Promyshlenno-Ekonomicheskaya Gazeta, 3, No. Ik, 3 (1958) 5. Zhvirblyanskiy, Yu. M., "Crystallization of Massecuite From the Second Sirup," USSR Patent No. 68,332 (April 30, 19U7) 6. Zhvirblyanskiy, Yu. M. j Volobuyeva, A. K. \ and Abragam, B. R., "Kinetics of Sucrose Crystallization in Impure Sugar Solutions," Sakharnaya Prom-st , l, 10-15 (19k9) 7. Idem . , "Laboratory Investigation of the Possibility of Crystallizing Sugar Without Boiling the Syrup," Tr. Vses. N.-I. In-t Sakharn. Prom-sti , 1953 9 Mo. 2, 13U-65; Ref. Zh., Khimiya7~1955 ~, No. 1398 "~ ~~ 8. Kamenetskaya, D. S„, "The Effect of Impurities on the Production of Crystal- lization Nuclei in Supercooled Liquids," Reports at the First Conference on Crystal Growth, 5-10 March 1956, 33-38 .9. Frenkel', Ya. I., Kinetic Theory of Liquids , State Technical Press, 195U (in Russian) 10. Danilov, V„ I, and Kanenetskaya, I. S., "Formation of Crystallization Centers in an Undercocled Liquid. VII „ Effect of Soluble Impurities on the Formation of Crystallization Centers in Azobenzene," Zh. Eksperim. i Teor. Fiz„ , 19, 313=18 (19U9) -^ 8 Idem. , Problems of_Metal Scie nce and Metal Physics, Symposium II, 1951? 3 12. Idenu, "Effect of Small Additions of Potassium on the Birth of Crystallization Centers in Undercooled Mercury," Dokl, AN SSSR , 68, No. k, 677-80 (19^9) 13. Eanilov, V. I., Problems o f Metal Science and Metal Physics, Symposium I , 19U? 5 7 lln Kamenetskaya, D. S., Probl ems of Metal Science and Metal Physics, Symposium III , 1952, 371 " 1$ 9 Gorbunova, - K, M. , "Laws of Crystal Growth Luring Electrolysis," Reports at the First Conference on Cry st al Growth , 5-10 March 1956, 39-U5 16. ..... 9 Popova, 0. S.| Sutyagina, A. A.j and Polukarov, Uy. M„, "The Growth Mechanism and Structure of Metal Deposits Produced by Electrocrystallization," Reports at the First Confer ence on Crystal Growth , 5-10 March 1956, U6-52 -72- 17. Shubnikov, A. V., How Crystals Grow , Academy of Science Press (USSR), 1935 18„ Ansheles, 0. 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K. and Sheftal, N N., "Monocrystals," USSR Patent No. 108,256 (October %$ 9 1957) 36. Pozdnyakov, P. G. and Shternberg, A A., "Primer for Growing Crystals," USSR Patent No. 100,988 (September 25, 1955) 37° Pozdnyskov, P. G. and Shternberg, A A., "Growing Crystals," USSR Patent No. 101,179 (October 25, 1955) 38 -— -^ "Growth of EDT Crystals," Kristallografiya , 1, 228-3U (1956) 39 o — — , "Growth of Crystals of Id^SO^ . H 2 0," Kristallografiya , 1,: 356-9 (1956) iiO. -. — -, "The Growth of Crystals of Potassium Tartrate," Kristallografiya , 1, 589-93 (1956) Ulo Arinshteyn, le. A., "The Influence of Diffusion on the Kinetics of Crystal- lization," Zhq Eksperim. i Teor. Fiz. , 30, No. 2, LtlU-6 (1956) U2 Ovsiyenko, D Ye., "The Kinetics of Crystallization of Aqueous Solutions of Sodium Chloride and Sodium Bromide on a Galena Surface," Voprosy Fiziki Metallov i Metallovedeniya, Akademiya Nauk Ukrainskoy SSR, Sbornik Nauchnykh Rabot , U, 55-69 (1953) i;3<. Salli, I. V., "The Decomposition Theory of Supersaturated Solutions," Nauchnyye Zapiski Dnepopetrovskogo Gosudarstvenogo Universiteta (SSSR), WT, 3-7=12 (1953) —-—_-— — — _ UU« ——-j! "A Theory of Crystal Growth," Zh P Eksperim, i Teor. Fj Zo 9 25, 208-lU (1953) U5o Danilov, V I and Malkin, '. I., "Experimental Confirmation of the Theory of Crystal Growth and the Relation Between the Equilibrium Forms and the Forms of Growth," Zh. Fiz. Khimii p 28, No. 10, 1837-UU (195U) U6. Danilov, V I and Pomgaybo, A G , "Crystallization of Sodium and Potassium," Dokl. AN SSSR , 68, 8U3-6 (19h9) U7. Danilov, V I j Kozachkovskiy, o E $ and Iabkovskiy, Ya. M. ,, "Formation of Crystallization Centers in an Undercooled Liquid. Iv. Activation of Impurities in Salol," Zh Q Eksperim i Teor. Fiz , 18, 886-92 (19U«) H8. Danilov, V. I., "Formation of Crystallization Centers in an Undercooled Liquid, V. Spontaneous Crystallization in Liquids," Zh. Eksperim. i Teor. Fiz. , 19 9 235-U1 (19U9) " ~"~ ~ - * U9. Danilov, V I. and Krishtal, Uy. A , "Formation of Crystallization Centers in an Undercooled Liquid. VI„ Spontaneous Crystallization of Mannitol and Ortho- -7k- chldronitrobenzene, w Zh. Fksperim,, j ^eor. Fiz,, . l^ . 30lj-12 (ir) t r\ tO, Danilov, V. I. and Ovsiyenko, D„ Ye., "The Emergence of Crystallization Centers in Supercooled Liquids. XI. The Emergence of Centers on Active Admixtures," Zh. Eksperim. i Teor. Fiz. , 21, 879-86 (195D $1, Idem. , "Crystallization of Hydroquinone on Single Crystals of Calcite," Dopovidi AN URSR , lggQ , 250-6 52. Danilov, V. I, • Lesnik, A. G. and Shnayder, B. I., "Generation of Crystal- lization Centers in Undercooled Liquids. IX. Formation of Crystallization Centers of - Salol on Rock Salt Particles," Zh. Ek sperim. i Teor. Fiz. , 19, 908-11 (19U9) 53. Petrov, D. A., "Deviation From Equilibrium Luring Crystallization of Solid Solutions," J. Phys. Chem. (USSR) , 21, 1UU9-60 (19^7) 5iu , and Raykovskaya, L, A., "Inter crystalline Liquation by the Method of Microhardness," Izv. AN SSSR. Otd. Khim. N. , 1952, 225-9 tt>o — —j and Bukhanova, A. A., "Utilization of the Phenomena Observed in the Crystallization of Metallic Melts," Alyuminiyevye Splavy. Ljt'e, Provkatka, Kovka, Shtampovka, Termoobrabotka (Moscow; Gosudarst. Izdatel. Oboron. Prom.) Sbornik , 1955 ] 65-83 " ' ~~ 56. — — — — , and Kolachev, B. A., "Impurity Redistribution Luring Crystallization and the Way This Appears in the Crystal Structure," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 126-3H 57 o Savitskiy, Ye. M. j Terekhova, V. F. and Khlopov, A. V. , "Chromium Recrystal- lization Diagram," Dokl. AN SSSR , 109 , 79U-5 (1956) 58. Savitskiy, Ye. M. j Tylkina, M. A and Turanskaya, A. N., "Investigation of the Recrystallization of Titanium and Its Alloys. I. Recrystallization Diagrams of Titanium," Izv. ATT SSSR , 7, lll-lli (1956) 59o Savitskiy, Ye. M. ; Tylkina, M. A, and Tsyganova, I. A., "The Effects of Alloying Additions on the Recrystallization Temperature and the Mechanical Properties of Titanium," Izv. AN SSSR. Otd. Tekhn. N„, 1958, No. 3, 96-103 60. Savitskiy, Ye. M. j Tylkina, M. A. and Tsygat ova, I. A., "Recrystallization Diagram for Molybdenum," Dokl. AN SSSR , 113 , No. 5, 1070-2 (1957) 61. Figurovskiy, N. A. and Komarova, T. A., "On the Mechanism of the Crystal- lization Process," Zh. Neorgan. Khimii , U, No. 3, 522-29 (1959) 62. Grigor'yev, A. T., "Equation of the Crystallization Surface of a Binary Chemical Compound, Melting Congruently in a Ternary System," Dokl. AN SSSR , §h, No. 5, 989-92 (1952) 63. , "Equations for Crystallization Surfaces in Ternary Reciprocal Systems," Dokl. AN SSSR , 88, No. 2, 273 (1953) 6U. Ansheles, 0. M. , "On the Theory of the Growth of Crystals," Uchenyye Zapiski -75- Leningradskoge Gosudarstvennogo Universiteta im A c A e Zhdanova , No, 215, 8I4. T19FD 65 o KIrgintsev, A. N., "Certain Mechanisms in the Formation of Anomalous Mixed Crystals," Ah, Neorgan. Khimii , 1, No. 10, 2390 (1956) 66. Lemmleyn, G G., "Theory of the Closing-Up of Cracks in a Crystal and the Equilibrium Form of a Negative Crystal," Eokl. AN SSSR , 8£ s No. 2, 283-6 (1953) 67. Kravchenko, V. M. , "Ideal Types of Equilibrium Diagrams for Liquid and Crystal- line Phases," Zh. Fiz. Khimii , 27, No 1, 6 (1953) 68. Liapunov, A. N. and Kholmogortseva, Ye. P., "Determination of the Growth Rate of Hydragillite Particles in an Aluminate Solution by the Linear Growth of the Crystal Faces," J. Appl. Chem. (USSR) , 30, No. 9, 1379 (1957) 69o Skryabin, A. K. , "The Kinetics of Crystallization Processes of Solutions and Melts," Zh. Fiz. Khimii, 31, No. h, 780-91 (1957) 70. Makarov, Ye. S., Crystal Chemistry of Simple Compounds of Uranium, Thorium, Plutonium, and Neptunium ,, Consultants Bureau, Inc., New York, 1959 71. -.— - 3 and Gudkov, L. S , "An X-ray Investigation of the Thorium - Zinc Alloys," Crystallography , 1, No. 6, 650 (1956) , Dokl. AN SSSR , 59, No. 5 (19U8) - — — , and Vinogradov, S. I., "The Crystal Structures of Tt^Zniy and U 2 Zni7," Crystallography , 1, No. 6, 63U (1956) -i— 9 and Levdik, V„ A. 9 "Crystal Structures of UGa and UGa ? ," Crystallography , 1, No. 6, 6hh (1956) Konobeyevskiy, S„ T„, "Phase Diagrams of Certain Systems Based on Plutonium, 1 * Proceedings of the Session of the Academy of Sciences USSR on the Peaceful Use of Atomic Energy , 1-5 June 1955, Div. Chem. Sci , 362-376 Makarov, Ye. ST, "Studies in Crystal Chemistry of Compounds of Variable Composition," N„ S. Kurnakov Institute of General and Inorganic Chemistry, Academy of Sciences USSR , Moscow, 21+, 28U-U19 (1953) Kapustinskiy, A. F., "Atomic and Ionic Dimensions of Transuranium Elements in Crystals," Kristallografiya , 1, 382 (1956) Makarov, Ye. S., "New Data on the Structure of Biln2 and the Probable Structures of TIBin 07 l cro? N aHgp, UZr and TiU " Crystallography , 3, No. 1, 3 72. Gorshteyn, G. I. and Silant'yeva, N. I., "The Distribution of Isomorphous and of the Isodimorphous Components Between the Solid and Liquid Phases in the Crystallization From Aqueous Solutions. I. The Equilibrium in Certain Systems with Components of the Sulfate Type at 20°C," Zh. Obshch. Khimii , 23, 1290- 1302 (1953) 73. Gorshteyn, G. I. and Silant'yeva, N I„, "The Distribution of Isomorphous and of Isodimorphous Components Between the Solid and Liquid Phases in the Crystal- lization From Aqueous Solutions. II. Equilibrium in Systems with Schoenite (picromerite)-type Double Salt Components," Zh. Obshch. Khimii , 2l| , 29-36 (195U) -76- 7U« Idem., "The Distribution of Isomorphous and of Isodimorphous Components Between the Solid and Liquid Phases in the Crystallization From Aqueous Solutions . III. Equilibrium in the System Co(NOo)p • ^0 at 20»," Zh. Obshch. Khimii , 2k, 201-3 (195U) 75„ Idem., "Study by Means of Radioactive Indicators of the Rules for the Distri- bution of Isomorphic Components in Crystallization From Aqueous Solutions. I. Study of the Equilibrium in the Copper Ammonium Sulfate - Zinc Ammonium Sulfate - Water System at 20*C, by Means of the Radioactive Isotopes Zinc (65) and Copper (6U)," Zh. Obshch. Khimii , 26, 1821-6 (1956) 76„ Gorshteyn, G. I., "Concerning the Limits of Applicability of the Linear Law of Distribution in Aqueous Salt Systems With True Isomorphous and Isodimorphous Components," Zh. ^eorgan. Khimii , 3, No. 1, 51-8 (1958) 77„ Pozin, M. Ye. and Muratova, M. I., "Crystallization of Potassium Chloride From Kainite Liquors," J. Appl. Chem. (USSR) , 30, No. 9, UU6-50 (1957) 78 Pozin, M. le. and Muratova, M. I., "The Quality of Potassium Chloride Obtained From Kainite Liquors of Different Composition," J. Appl. Chem. (USSR) , 30, No. 9 9 1U51-5U (1957) 79. Goroshchenko, Y a. G., "The Niobium Sulfates," Zh. Neorgan. Khimii , 1, 903 (1956) 80. 9 "The Double Sulfates of Niobium With Ammonium Sulfate," Zh. Neorgan. Khimii , 1, 909-lh (1956) 81. Goroshchenko, Ya. G OJ "The Double Sulfates of Tantalum With Ammonium Sulfate," Zh. Neorgan. Khimii , 1, 915- 20 (1956) 82. Ravich, M. I. and Borovaya, F. Ye., "Crystallization of Mixtures of the Sulfate, Chloride, and Hydroxide of Sodium in the Presence of Steam," Vnutrikotlovya Fiziko-Khimicheskie Protsessy, Akademiya Nauk SSSR, Enerpeticheskiy I nstitut im G, M. Krzhizhanovskogo , 1957? 23U-50 83o Mironov, K. Ye.j Pronina, M. Z. and Tokareva, S. A., "An Investigation, of Crystallization in the Systems H 2 02 - NaClOi - H 2 and HgOg - LiClo^ - H 2 0," Zh. Neorgan. Khimii , 3? No. 2, 508-16 (19587 8Uo Akopov, Ye„ K. and Bergman, A. G., "Stable Section LiSO^ - NaCl 2 - K 2 C1 2 of Quadruple Mutual System of Chlorides and Sulfates of Lithium, Sodium, and Potassium," Izv. Sektora Fiz.-Khim. IONKh AN SSSR , 25, 263-7 (195U) 85o Banashek, Ye. I. and Bergman, A. G., "Nondiagonal Irreversible Mutual System of Fluorides and Chlorides of Lithium and Strontium," Izv. Sektora Fiz.-Khim. Analiza IONKh AN SSSR, 25, 2U5-5U (195U) 86, Nikolayev, N. S. and Buslayev, Yu. A., "Solubility in the System HF-I 2 0^- - H 2 0," Zh. Neorgan. Khimii, 1, 1672-5 (1956) 87. Voskresenskaya, N. K. and Berul', S. I., "Equilibriums in the System WaNOo - KN0 2 - H 2 at 70°," Izv. Sektora Fiz.-Khim. Analiza IONKh AN SSSR , 25, 31U-19 (195U) ~" -77- 88. Slavnova, Ye„ N., "Lata on the Interactions of Organic Impurities With Inorganic Crystals," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 117-25 89. Belyustin, A, 9. and Dvoryankin, V. F 0J "The Effect of Degree of Super- saturation on the Crystal Shape," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 139-U1 ' 90. Saratovkin, I. D„, Dendritic Crystallization , Consultants Bureau, Inc. (trans.), New York, 1959 . (Original publisher: Metallurgizdat, 1953) 91. Ansheles, 0. M. , Introduction to Crystallography , Zhdanov State University, Leningrad, 1952 92 8 Gorodetskiy, A. F. and Saratovkin, D. D., "Dendritic Forms of Crystals Produced in Antiskeletal Growth," Reports at the First Conference on Crystal Growth, 5-10 March 1956, 151-8 93° Lemmleyn, G„ G. and Dukova, Ye. D., "Formation of Spiral Dislocations During the Growth of a Crystal,." Kristallografiya , 1, 351-5 (1956) 9Uo Idem. , "The Rate of Tangential Growth of the Elementary Layers of P-Toluidine," Kristallografiya , 1, 112-18 (1956) 95o Lemmleyn, G G., "Experimental Production of Crystals with Equilibrium Forms," Dokl. AN SSSR , £8, 973-U (195k) 96. Malkin, V. I., "The Dependence of the Form of Crystal Growth on the Rate of Growth," Problemy Met alio vedeniya Fiziki Metallov, Institut Metallovedeniya i Fiziki Metallov, Shornik Trudov , U 3 113-20 (1955) 97o Ivantsov, G P„, "Growth of Spherical and Acicular Crystals of Binary Alloys," Dokl. AN SSSR 9 83, 573-6 (1952) 98o Indenbonn, V. L OJ1 "Macroscopic Theory of the Formation of Dislocations During Crystallization," Kristallografiya , 2, 59U-603 (1957) 9? a Zaytseva, N G. and Smirnova, A„ M , "The Effect of Surface-Active Substances on the Crystallization of Hydrated Tricalcium Aluminate," Kolloidn. Zh. , 20 , No. 5, 636-9 (1958) 100o Solov'yeva, Ye. S and Segalova, Ye Ye., "The Kinetics of the Crystallization Structure Formation in the Hydration Hardening of Tricalcium Aluminate," Kolloidn. Zh a , 20, N 0o 5, 620-7 (1958) 101. Tovbin, M. V. and Krasnova, S. I., "The Stability of Supersaturated Solutions of Slightly Soluble Salts," Ukr. Khim. Zh. , 21, 32-8 (1955) 102. Mokiyevskiy, V. A., "The Effect of External Conditions on the Form of Growing Crystals," Kristallografiya , 1, No. h, 3-U6 (1955) 103. Alekseyeva, N„ P., "Crystallization of Potassium Alum From Safrine-Containing Solutions," Kristallografiya , 1, No. U, 3-U6 (1955) -78- lOka Korol'kov, I. I. and Tyagunova, Z. A., "The Effect of Colloids on the Crystal- lization of Gypsum, ,r Gidroliznaya i Lesokhimicheskaya Promyshlennost ' (SSSR) , 9, No. 8, 8-9 (1956; 105. Avakyan, S. V. and Lashko, N. F., ,f 0n the Nature of Eutectic Alloys. II. On Eutectic Crystallization in the Presence of Surface-Active Substances," Zh. Fiz. Khimii , 23, No. 6, 729-35 {19k9) 106 o Stepanov, I. V. and Feofilov, P. P., "Artificial Fluorite," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 181-90 107. Vasil'yeva, M. A., "Growing Lithium Fluoride and Sodium Fluoride Single Crystals of High Transparency in the Ultraviolet and Infrared Spectrum," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 191-6 108. Belyayev, L. M.; Vitovskiy, B. V. and Bobrzhanskiy, G. F. , "Methods of Growing Scintillation Crystals for Scintillation Counters," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 197-206 109. Dzhelepov, V. P„ * Golovin, B. M. and Saratov, V. I., "Elastic Scattering of Neutrons by Neutrons at an Energy of 300 m.e.v.," Eo kl. AN SSSR, 99, 9h3 (195k) ~~ 110. Zavoyskiy, Ye. K.j Smolkin, G. Ye.j Plakhov, A. G. and Butslov, M. M. , "A Luminescence Camera," Lokl. AN SSSR , 100 , 2U1 (1955) 111. Petrov, E. A. and Zemskov, V. S., "Apparatus and Methods for Growing Single Crystals of Semiconductors," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 207-lH 112. Kapralov, K, V.; Koritskiy, Yu. V. and Sheftai, N. N., "The First Experiment on Growing Large Mica Crystals," Reports at the First Conference on Crystal Growth , 5-10 March 1956," 215-18 113 o Yamzin, I. I. and Leyzerzon, M. S e , "The Properties and Uses of Synthetic Mica," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 219-26 lliu Rez, I. S. and Tsinober, L. I., "Growing Single Crystals of Sorbitol Hexa- acetate," Reports at the First Conference on Crystal Growth , 5-10 March. 1956, 227-31 115» Butuzov, V. P. and Bryatov, L. V., "Growing Quartz Crystals," Reports at the First Conference on Crystal Growth , 5-10 March 1956, 2^1-UU 116. Novosil'tsev, N, S.j Khodakov, A. L. • Sholokhovich, M. L. • Fesenko, Ye. G„ and Kramarov, 0. P., "Growing and Investigation of Single Crystals of Ferro- electric Materials," Izv. All SSSR. Ser. Fizicheskaya , 21, 295-30U (1957) 117. Grechnyy, la. V., "The Probability of Formation of Crystalline Nuclei in Binary Melts of the Eutectic Type," Dokl. AN SSSR , 8Lj.', No. 1, 8Q-92 (1952) -79- 118. Melnik, B a D , "Discussion of Industrial Methods of Salt Production," Khim. Prom-st' , 9, 193-6 (1956) 119. Yarmolinskiy, M. B„ , "Crystallization of Sugar From Its Aqueous Solutions," Tr. Vses. N.-I. In-t Sakharru Prom-sti ? 1953 , No. 2, 10U-15 120. Mircev, A. and Sandera, K. , "Addition to the Masse-cuite of the Final Product of Substances that Promote Crystallization of the Sugar," Ref. Zh., Khimiya , 1958 9 No. 1, 2782 121. Kapustin, A. P., "The Effect of Ultrasonics on the Kinetics of Crystallization," Izv. AN SSSR. Ser. Fizicheskaya , Ik, 357-65 (1950) 122. — — - s "Effect of Ultrasound on the Crystallization of Organic Substances," Zh. Tekhn. Fig. , 22, 765-72 (1952) 123 . __„__ ? "Experimental Study of the Effect of Ultrasound on the Kinetics of Crystallization," Tr. In-ta Kristallogr. AN SSSR , 10, 177-8 (195U) 12Lu — — ■, and Kavalunayte, V e Ye., "The Effect of Ultrasound on the Crystal- lization of Single Crystals of Aluminum Potassium Alum," Kristallog rafiya, 1, 737-8 (1956) 125. — ~«~, "Orientation of Crystals Growing Under Supersonic Waves," Dokl, AN SSSR, 71, No. 3, U51-2 (1950) 126 Gudtsov, N„ T., "The Effect of Ultrasound Upon the Phenomenon of Orthotropism in Organic Substances," Dokl. AN SSSR, Novogo Ser. , 71, No. 2, 273 (1950) 127. Polototskiy, I. G.» Beniyeva, T B Ya. and Khodov, Z. L. , "Effect of Ultrasound Vibrations on the Crystallization Process," Tr. In-ta Chernoy Metallurgii, , AN SSSR , 6, 91 (1953) 128. Kapustin, A. P., "Spontaneous Formation of Centers of Crystallization in an Undercooled Melt in an Ultrasonic Field," Uchenyye Zapiski, Moskovogo Gosudarstvennyy Pedegogicheskiy Institut im. V. I. Lenina, Kafedra Obschchey Fiziki , bB, 53 U95U) ' 129 o Vitovskiy, B. V. , "Increasing the Growth Rate of a Crystal by Exposing It to Vibrations of Sonic Frequency," Tr.. In^ta Kristallogr . AN SSSR , l£|&g No. 11, 221-2 130. Petrov, D, A. and Kolachev, B. A., "Use of Crystallization to Obtain Ultra- Pure Substances," Zh. Fiz. Khimii^ 30, No. 10, 231*0-7 (1956) 131. Privalov, V. Ye„, "Tube Crystallizer for Naphthaline Fraction," Koks i Khimiya , 1959 9 No. 3? U6-9 132. Tamarin, V". M , "On Calculating Mechanical Cryst^ilizers for Naphthaline Fractions," Koks i Khimiya , 1958, No. 5, 38-1*3 133. Matusevich, L„ N , "Mechanical Laboratory Crystallizer," Zavodskaya Labor - atoriya, 23, No. 6, 757-9 (1957) =80- 13U. Bookin, M. L. and Semerchan, A. A., "Growth and Adhesion of Crystals Under the Action of Ionizing Radiation," Vestn. ATI SSSR , 28, No. 1, 69 (1958) 135. Petrov, D. A. and Shashkov, Yu. M. , "An Apparatus Without Crucible to Crow Crystals of High-Activity Metals Directly From Powder," Izv. AN SSSR. Ot'd. Tekhn. N., 1957, No. 5, 102-3 -81- EXTRACTION The Soviet literature on extraction is substantial in quantity, but not extensive. Its quality is generally below average by Western standards, although recent papers indicate considerable improvement and a growing trend toward origi- nality, particularly in the treatment of theory. Emphasis on process development appears to be increasing but reduction of new processes to plant practice is retarded by limited capacity for original equipment design. Soviet work in extrac- tion will be discussed under four general headings? theory and calculation methods, equilibrium studies, processes, and equipment. Theory and Calculation Methods Soviet scientists appear to have done little original work on extraction theory and calculation methods. Until very recently, papers on these subjects have been virtually absent from their publications . As confirmed by their own review articles, the Soviets are familiar with Western developments in extraction technology and have generally accepted these, offering only occasional improvements and empirical exten- sions. 2/2/ For example, vector projections were suggested as convenient for graphical interpretation of phase diagrams, j/ N. I. Smirnov and colleagues have studied droplet motion in liquid media under laminar, transition and turbulent flow conditions °, they developed a series of empirical equations pertinent to extraction hydraulics. U/5/6/ V. V. Kafarov has presented a generalized correlation of flooding- velocity data in packed towers, if However, the Soviet literature since 195 7 shows marked improvement in quality and a shift in emphasis toward more fundamental work. Leading this trend is V, V. Kafarov of the Moscow Technological Institute imeni D. I. Mendeleyev, who is seeking to extend the turbulent-layer theory (see discussion of adsorption) to extraction and other mass-transfer processes. 2/ 8/ 9/ 10/ In his latest paper, Kafarov appllties this approach to the interpretation of experimental data on phase contact between mutually insoluble liquids with mechanical stirring, 11/ Other Soviet workers are beginning to follow Kafarov 1 s lead. For example, Go K. Goncharenko and A. P. Gotlinskaya analyzed results from over 100 liquid- liquid extraction experiments with various substances ° 9 they found that mass-transfer coefficients under fully developed turbulence are independent of distribution coefficients and concluded that mass-transfer rates are then controlled by an inter- face resolution reaction involving breakdown of a solvate shell in one solvent and formation of a new shell in the other. 12/ V. A. Marinin is investigating the-, activation energy of diffusion processes by means of viscosity measurements. 13/ From theoretical considerations of bond energies and molecular motion, G. M. Panchenkov has developed a generalized equation for the temperature~dependence of diffusion coefficients in liquids s e log D » log A - ~ +oC log T where o is the energy of a single liquid molecular bond and A and ©C are constants derived from physical properties. lU/ By departing from the customary "energy^ of activation" approach to diffusion, which would lead to only the first two terms on -82- & e right side of his equation, Panchenkov may have made a significant new contribu- on. However, experimental data to support his equation are still in the process collection. Ik/ 15/ Over a period of years, I. L. Krupatkin* has been conducting an extensive study phase stability and layer formation in liquids. 16-3U/ Much of this work has nsisted of data collection and empirical correlation on binary and ternary systems mposed of various organic acids, amines, alcohols and water; some of these involve npound or complex formation, and others do not. Krupatkin classifies ternary stems into three types, depending upon whether one, two, or all three of the binary stems are completely miscible. He suggests a "law of inverted similarity" which lates the shapes' of the binary separability isotherms in a given system and permits Tiited qualitative estimation of ternary ohase behavior from binary system data. 23/ theory for the mechanism of liquid stratification involves a three-stage polyther- process of liquid solution decomposition, followed by a diffusional phase-forma- on process. 27 / Krupatkin has suggested and applied a method for studying chemical beraction in multiphase liquid systems by means of two solvents of different Larities. 22/ 29/ 30/ His latest papers depend less on empirical analysis and more thermodynamic reasoning, seeking to show that metastable separations are governed the same principles which apply to stable phase equilibria. 32 / 33 / 3h / Krupatkin 1 s tensive accumulation of data and experience in this area makes him a leading Soviet scialist on liquid separations. His papers indicate that he is not directly inter- bed in extraction applications, but his findings could form the basis for significant rk by others. Recent research in the USSR on extraction theory is not entirely original, since Inittedly much of it stems from current discussions in the Western literature; but [ is evidence of the present sophistication of Soviet specialists in this area and I their probable capability to contribute significantly now and in the future. Thus, ! s Soviet attitude toward extraction fundamentals, backward and imitative as recently I 1956, appears to have come of age rather rapidly. ,i j'l ilibrium Studies Recent Soviet research on extraction equilibria is summarized in Tabl^ on page 107. Wit W a few exceptions, water is involved as one of the solvents. No general pattern j evident from this work, but some of the systems studied suggest orientation tox^ard I pharmaceutical industry. 17./ 2U/ 26/ 30/ 31/ 51/ 5>2/ The data on fused salt [stems may have metallurgical applications. 62-6"^ 7 Until sometime in 1957, Krupatkin was at the Cherkassy Pedagogical and Teacher's stitute. 16/ 30/ His most recent papers place him at the Yaroslavl Technological ititute 327 or the Ivanovo Chemical Technology Institute, Chair of Inorganic smistry. 33/ 3U/ -83- During the past two years several papers reporting on systems related to nuclear energy developments have appeared, suggesting that some of the informal tion in this area accumulated in the Soviet Union is now being released for publication,, 57/ 56/ 59/ 61/ However , the data disclosed in these papers appear rather limited,, Soviet interest in extraction equilibria seems to be concentrated at a relatively small number of research institutions. For example, eleven of the entrees in Table I are from the work of I. L. Krupatkin at the Cherkassy Pedagogical and Teacher ! s Institute. l6/l7/l9/2[i/2^/32/3l/^/ Five references are papers by S. Shu Byk and colleagues at the Scientific Research Institute on Synthetic Alcohols and Organic Products in Moscow. 37/ U5/ U6/ hi/ h^/ Five others are from the Leningrad State University imeni A. A. Zhdanov. 38/"TO/ r " Aleksey Vasil'y ev ich Storonkin at Leningrad State University is the leading Soviet' specialist in thermodynamic analysis of phase equilibria^ his principal : asso- ciates are N. P. Markuzin, A. G. Morachevskiy and M. P. Susarev. They have published a series of paoers deriving mathematical relationships for thermodynamic equilibrium in multicomponent systems. 7 1~?6/ Storonkin has coined the term "isotherm-isobar" for the family of curves (or surface) expressing the possible temperatures and pressures of two-phase coexistence in ternary systems j he has discussed theoretically possible shapes for isotherm-isobars and demonstrated their applicability to solubility studies. l\xf He has also suggested some semi-quantitative rules for predicting ternary phase relationships from data on binary mixtures containing common components. 72/ Storonkin' s thermodynamic reasoning follows established conventional lines, but it is rigorous and thorough, as evidenced by his generalized mathematical treatment of open and closed systems involving n-components and r-phases. 76/ In applying thermodynamic analysis to experimental data, Storonkin appears interested primarily in vapor-liquid equilibria. However, several of his papers in this area also discuss solution effects pertinent to extraction. U9/ 50/ 56/ 77/ 78/ At the M. I. Kalinin Polytechnic Institute in Leningrad, A. F. Alabyshev and M„ F. Lantratov have been studying the thermodynamic s of fused salts and molten metals \ 79-8%/ Morachevskiy has also been associated with some of this work 83-85/ Their experimental technique is electrochemical, evaluating the activity of solution components from potential measurements on concentration cells, and the quality of the work appears to be excellent,, The fused salt studies have covered the activity of lead, cadmium and zinc chlorides in sodium potassium and barium chloride melts. 79-81/ The molten metal systems investigated include sodium «= cadmium, 83/ lead - sodium - cadmium, §hf and zinc - antimony = tin 82/ | in this work entropy, free energy, and enthalpy effects were calculated, in addition to activity coefficients. A recent paper by these authors reviews and summarizes various Soviet studies of liquid metal thermodynamics. 85/ In view of current Western work on liquid metal extraction processes, both for general metallurgical applications and for processing of nuclear fuels and fission products, Soviet activity and competence in this area may be quite significant. A. M. Rozen and L. P. Khorkhorina have discussed the thermodynamics of the equilibrium distribution of uranyl nitrate and nitric acid in the extraction of aqueous solutions with mixtures of tributyl phosphate (TBP) and organic solvents* 86/ 87/ They analyzed their own data 61/ and used some of the concepts suggested by Fomin and Mayorova, 60/ but they referred extensively to British literature (primarily to the work of H.AoC. McKay, et. al., Trans. Faraday Society). They -8U- concluded that in these systems distribution constants depend strongly on the non- ideality of TBP - organic solvent solutions, which tends to promote extraction. Rozen and Khorkhorina derived a general equation for calculating the combined distri- bution of uranyl nitrate and nitric acid between the aqueous and organic phases; 8?/ however, use of this equation requires a knowledge of distribution and activity coefficients o Rozen also studied the effects of various nitrates as salting- out agents, suggesting an equation for correlating these effects in terms of conventional solution parameters. 86/ The line of reasoning followed in these papers parallels that customarily used in the Western literature, offering little in the way of theory development or extension. However, the work of Rozen and Khorkhorina demonstrates competence for employing and understanding contemporary reasoning and knowledge in this area. Extraction Processes Recent literature points to increasing emphasis on extraction process development in the Soviet Union. Much of this effort centers on methods for preparing nuclear fuels and separating fission products and on processes related to metallurgical indus- tries. However, interest in organic processes is also evident, as well as noteworthy activity in the application of extraction techniques to analytical chemistry. A leading Soviet specialist in the extraction of uranium and fission products is V. M. Vdovenko at the Institute of Radium imeni V. G. Khlopin. His publications are all very recent (1957-1959) and cover both process and analytical applications 88-90/ as well as basic chemistry. In the latter category, Vdovenko and colleagues have reported extensively on solubility relationships for uranyl nitrate in dibutyl and diethyl ethers; 68-70 9 91/ on heats of solution in these systems; 92/ on the dis- tribution of uranyl nitrate and other metal nitrates between water and various ethers and esters; 93-95/ and on uranyl chloride complexes in organic solvents. 96/ Studies such as these apparently provide the fundamental data for Vdovenko 's extraction process work. For example, his systematic investigation of the distribution of uranyl, neptunyl, and plutonyl nitrates between aqueous solutions and oxygen -containing organic solvents led to the development of a two-cycle extraction process for separating and recovering practically pure uranium and plutonium from fission products, using a non-explosive mixture of dibutyl ether and carbon tetrachloride as the solvent. 97 -99/ In another process study, still in the laboratory stage, Vdovenko and L. N. Lazarev are investigating the extraction of uranyl acetate with aniline. 100 / V D. Mikol'skiy and V. S. Shmidt have reported on the extraction of ruthenium in the form of nitrosonitrates from aqueous solutions of irradiated uranium. 101 / I. V„ Shilin, A. S. Solovkin and associates are studying tributyl phosphate extrac~ tion of perchloric acid, with the aim of developing a process for recovering and concentrating uranium as uranyl perchlorate. 102/ 103/ Recent Soviet publications on metallurgical extraction processes show a wide range of interests, suggesting an extensive program of mineral resources development. Some of this work is directed at up-grading waste materials. For example, V. G. Agyenkov and Ya. Ya. Miklun have reported on methods of improving the extraction of gold from sulfide concentrates. 10lt/ L. L. Chermak has investigated the distribution of cobalt in molten converter slag; 105/ this work resulted in a patented process for extracting nickel and cobalt from slags by means of cadmium sulfide mat. 106/ Ya. Z. Malkin and associates developed a method for extracting tellurium from lead production wastes. 107/ v. G. Kovyrshin and V. K. Apollonov have reported successful laboratory and pilot plant studies on the extraction of calcium molybdate mother liquors for -85- molybdenum and rhenium recovery, 108/ ■. A. I s Mikheyeva and V, B. Aleskovskiy have proposed a novel scheme for recovering copper from dilute solutions by countereurrent- contact with alumino-silicate particles carrying adsorbed ammonia. 109/ Another unusual technique reported recently in the Soviet literature is a "mercury trap" method for separating rare metals (gallium,, indium and th alli um) by extracting them from water solution with zinc amalgam and then electrolyzing the amalgam,, 110/ In the area of new but more conventional processes are flotation studies of indium ore recovery by 0„ A e Shubina and L. I. Ghechulina. Hi/ and of phosphate rock enrichment by L, I. Stremovskiy 132/ Extraction of alumina from shale ash with nitric acid has been investigated by R. I. Agaladze and I. M. Arazashvili, 113/ !«• A. Bylina and associates have experimented with carbon tetrachloride extraction of germanium from coal, lilt/ A. M. Rozen and four colleagues have patented a process for extraction separation of metals from aqueous solution, by means of fatty acids dis- solved in kerosene. 115/ Most of the above process literature appears to result from laboratory investigations 5 suggesting limited Soviet capability for carrying new extrac- tion process developments into successful plant operation. Relatively few Soviet studies of organic extraction processes have been published recently ^ and these do not emphasize any particular area of interest. However, they do show more of a tendency toward experimentation on a pilot plant scale than indicated in the metallurgical extraction work. A, V. Mazov and colleagues reviewed the practice of extractive separation of coal tar fractions in the USSR and reported pilot plant results on a new process for phenol recovery using aqueous, methanol solutions. 116/ V N„ Kozlov arid G„ A, Tokareva studied the extraction of formic, acetic, propionic, and butyric acid mixtures in a ten-stage counter-current apparatus, using diethyl ether, ethyl acetate $ and butyl acetate as solvents „ 117/ Several papers proposing new extraction processes for the petroleum industry have appeared. For example , M„ A. Kapelyushnikov and T. P. Zhuze have suggested the use of compressed hydrocarbon gases at 1QQ-15>0 atmospheres pressure for extracting resin from crude oil. 118 / B. K. Marushkin and colleagues studied the effects of recycle on the extraction of crude oil with phenol. 119/ A. K. Seleznev proposed the use of beta- chlorodiethyl ether and dichloroe thane mixtures for solvent dewaxing of lubricating oils . 120 / V. B. Kogan and associates reported that ethylene glycol is an effective solvent for extracting alcohols from mixtures with hydrocarbons. 121/ A number of Soviet chemists have become specialits in the application of extrac- tion techniques to chemical analysis. These include V. M. Vdovenko at the Institute of Radium imeni Y G„ Khlopin,, whose work is cited above | 88°96/ I. P. Alimarin and I. M. Gibalo at Moscow State University imeni M„ V. Lomonosovf and V. I, Kuznetsov and K. V„. Troitskiy at the Institute of Geochemistry and Analitical Chemistry imeni V. I. Vernadskiy. Alimarin and Gibalo have developed methods for extracting niobium,, tantalum, and tungsten from hydroxyquinolate complexes with isoamyl alcohol and chloroform 122/ and from cupferronates with chloroform P ethyl acetate s or diethyl ether. 123/ They have also devised a technique for separating beryllium from other metals by extracting a mixture of acetylacetone complexes with carbon tetrachloride. 12h/ Recently Alimarin reported a new method for isolating neptunium from solutions containing uranium and plutonium by extraction with netroso-naphthol dissolved in butyl alcohol. 125 / ~86~ Kuznetsov, who publishes actively in various areas of analytical chemistry, has made an extensive review of the theory and practice of extractional separation of metals 126 / His own contributions include a procedure for extracting vanadium from acid solutions with ketones, 127/ and a new technique for the rapid separation of various groups of metals by extraction with fused low-melting organic substances* 128/ Troitskiy has been studying niobium extraction from thiocyanate complexes by organic solvents, using radioactive tracer techniques. 129/ Other recent Soviet contributions worthy of mention in this area are discussions of the thermodynamics of analytical extractions by N. P. Komar 130/ and by I. M. Xcrenman and F„ R. Sheyanovaj 131/ 132/ studies by F. G. ZharovskLy of molybdenum and tungsten extraction from chloride complexes j 133/ and investigations of cerium extraction Ibv V. M, Klinayev and M. M. Senyavin 13k/ and by A. V. Nikolayev and associates. 135 Corresponding to growing Soviet interest in extraction processes, recent literature shows increased activity in the study of extraction equipment. Much of this work is concerned with apparatus and operating techniques originated outside of the Soviet Union, suggesting that Soviet specialists in this area are currently engaged in "catching up w with foreign advances and that their own capacity for original equipment design in support of new process developments still is rather limited. For example, a review of operating characteristics of various extraction devices, published in 1958 by N. I. Gel'perin and A, G. Liakumovich, contains 68 references, of which only 9 are Soviet, 2j6 are English and ten American. 136/ A paper by S. M. Karpacheva and co-workers reports operating tests on a pulse column modeled after an American patent. 137/ 0r o P<> Piterskikh and Ye, R. Valashels describe and analyze the performance of three centrif- ugal extractors, all of non-Soviet design. 138/ A recent paper by S. Z. Kagan and associates, reporting a series of tests on rotary disc extractors, cites 26 references, of which only six are Soviet. 139/ However, some noteworthy new equipment suggestions have appeared in the Soviet literature. Based on a fundamental study of liquid dispersion in flow through nozzles, N. I. Gel'perin has designed an extraction column employing injectors at each to insure fine dispersion of both feed solution and solvent. An experimental model of this injector column has been tested with a water- uranyl nitrate- tributyl phosphate system, lltl/ and is claimed to be twice as effective as a plate or packed column of conventional design. ll|2/ S, M. Karpacheva and co-workers suggest that extraction efficiency in this type of column can be increased further by introducing multiple jets. lli3/ Gel'perin has also devised a new technique for laboratory extractions whereby a volative solvent is introduced as vapor into a column, achiev- ing improved mass transfer by solvent condensation, ihh/ He is currently studying the operation of an experimental column containing alternate mixing stages and sections packed with Razchig rings. Ili5/ V. V. Kafarov, whose contributions to extraction theory are discussed above, has also studied the effectiveness of liquid jets as extractors. II46/ Recently Kafarov patented a new column design consisting of pump-mixers and annular settling chambers arranged alternately. lhT/ Another scheme for jet column operation, whereby several jets for feeding fresh solvent are spaced along the height of the column, has been patented by I. V. Filippov. 1^8/ As an alternate to using liquid jets, N. P. Gallon and associates have proposed the introduction of an air stream near the bottom of plate columns to improve light-phase dispersion. Ik?/ -87- Three recent papers by staff members of the Moscow Chemical Machine Building Institute infer strong emphasis there on extraction equipment development* A. N. Planovskiy and S. N. Bulatov have studied drop size and formation frequency in relation to hydrodynamic conditions in sieve°plate extraction columns, using both electromechanical and oscillographic methods, l50/ A. K. Skryabin has compared theoretically and experimentally the relative merits of jjet dispersion of the light and the heavy phases in extraction columns* 15>l/ I. I* Salamatov and G, M. Veksler have designed a new continuous rotary extractor that operates without pumps and achieves efficient and rapid extractions* 15>2/ It is interesting to note that nearly all of the significant current Soviet work on extraction equipment is at institutions located in Moscow, The last three papers mentioned are from the Moscow Chemical Machine Building Institute, Gel'perin is at the M. V,, Lomonosov Institute of Fine Chemical Technology s as of 193>8, lit 2/ Kafarov is at the Moscow Technological Institute imeni D, I* Mendeleyev, as of 19S>9« 11/ 111?/ It thus appears that a concerted effort may be underway to hasten correc- ^Ton"of the Soviet weakness in this area of chemical technology* *88- REFERENCES — EXTRACTION lo Gel'perin, N. I. and Liakumovich, A. G., "Extraction from Solutions," Khim. 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Water - Dioxane - Electrolyte,"' Zh. Obshch. Khimii, 27, 2025-30 (1957) 5U. Zhdanov, A. K„ and Sarkazov, M. A., "Solubility in the Systems Water - Ethyl Alcohol - Ammonium Hydrogen Fluoride at 25°," Zh. Obshch. Khimii , 2U, 759-62 (1951|) 55. Zhdanov, A. K., "Solubility in the Ternary Systems Water - Ethanol - Solium Fluoride at 0° and 25°, n Zh. Obshch. Khimii,, 2U, 762-66 (195U) 56. Storonkin, A. V, and Simanavichus, L. Ye., "Three-phase Equilibria in the System Calcium Chloride - Methyl Alcohol'- Water," Vestn. Leningr. Urwta, 12, No. 22, Ser. Fiz. i Khimii, No. U, 103-19 (19577 57. Rozen, A. M. and Moiseyenko, Ye. I c , "Distribution of Plutonium During Extraction with Tributyl Phosphate," Zh. Neorgan. Khimii, h 9 No. 5, 1209-15 (May 1959) 58. Shevchenko, V, B.j Povistkiy, N. S.j Solovkin, A. S.| Shilin, I. V.j Lunichkina, K. P. and Tsvetkova, Z. N., "The Extraction of Nitric Acid with Tributyl Phosphate," * Zh. Neorgan. 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I. 3 Ter=0ganesov, N. A. and Rozen, A. M., "Separation of Metals by Extraction," USSR Patent No. 11U,038 (July 30, 1958) II60 Mazov, A. V.j Turskiy, Yu. I. and Danchenko, L. Ye., "Separation of Phenols from Tar Fractions with Aqueous Solutions of Methanol," Khimiya i Tekhnol. Topliv i Masel, 1958, No. 10, hh-9 -96- 117a Kozlov, V. N. and Tokareva, G. A., "Counter-current Process of Extraction of Formic, Acetic, Propionic, and Butyric Acids from Aqueous Solutions with Organic Solvents," Trudy Instituta Khimii (Ural' skiy Filial A kademii Nauk SSSR), Sbornik Rabot , 2, No. 1, 25-51 (195«) 118 „ Kapelyushnikov, M. A. and Zhuze, T. P., "A Method of Extracting Resin from Crude Oil Products," Byulleten' Izobreteniy , 1958 , No. 6, 56 119. Marushkin, B. K.$ Bondarenko, M. F.j Tsalik, V. L. and Baydavletova, F„ G.j, "The Effect of Recycling on the Definition of Separation During Purification with Selective Solvents," Khimiya i Tekhn. Topliv j Masel, 1958 , No. 8, 21-2U- 120. Seleznev, A. K., "Application of Beta-Chloro-Ethers in Combination with Dichlorocoumpounds for the Deparaffination of Aviation Oil," Zho Prikl. Khimii, 32, No. 2, 1+33-35 (February 1959) 121 „ Kogan, V. B.j Fridman, V. M. and Romanova, T. G., "The Separation of Mixtures of Alcohols and Hydrocarbons by the Method of Extraction," Zho Prikl. Khimii, 32, No. k, 8U7-52 (1959) 122. Alimarin, I. P. and Gibalo, I. M., "Extraction of 8-Hydroxyquinolinates of Niobium, Tantalum and Tungsten," Yestnik Moskovskogo Universiteta. Seriya Matematiki, Me khan ki, Astronomii, Fiziki i Khimii. 11, No. 2. iBT-B (19^6) ' -^3° Idem., "Extraction of Niobium, Tantalum, and Titanium Cupferonates, " ) Dokl. AN SSSR, 109, 1137-39 (1956) ^-2^° Idem., "Separation of Beryllium from Aluminum and Other Elements by Extraction Method," Zh. Analit. Khimii, 11, 389-92 (1956) 125 o Alimarin, I. P.| Zolotov, Yu. A. and Pal 1 shin, Ye. S., "Extr actional Isolation of Quinquevalent Neptunium," D okl. AN SSSR , 12h, 328-30 (1959) — ~~ 126. Kuznetsov, V. I., "Chemical Theoretical Bases of the Extractional Isolation of Metals," Uspekhi Khimii , 23, 65U-96 (195U) 127 „ ——-.j "Extraction of Quinquevalent Vanadium from Hydrochloric Acid Solutions with Organic Solvents," Zh. Obshch. Khimii, 22, 2083-90 (1952) ~ 128. — — —j and Seryakova, I. V., "Separation of Elements by Extraction with the Application of Low-Melting Organic Substances," Zavodskaya Labor at or iy a, 23, No. 10, -1176-80 (October 1957) 129. Troitskiy, K. V„, "Investigation of the Extraction of Niobium Thiocyanate Complexes with Organic Solvents by Means of the Radio- active Isotope Wd?5 9 " Zh. Analit. Khimii, 12, No. 3, 3l9-5h (May- June 1957) 130. Komar, N. P., "Distribution of Complex Compound Between Two Solvents," Zh. Neorgan. Khimii, 2, 1015-2U (1957) -97- 131. Korenman, I. M. and Sheyanova, F. R., "Extraction as Method for Physicochemical Analysis/' Zh. Analit. Khimii, 12, 28^-95 (1957) 132 o Idem ., "Some Problems of the Theory of Extraction," Izvestiya Vysshikh Uchebnykh Za vedeni y. Khimiya i Khimicheskaya Tekhnologiya, £ No. 2, 151-56 (1959) 133. Zharovskiy, F. G. "Extraction of the Chloride Complexes of Molybdenum and Tungsten in the Presence of Phosphoric Acid," Ukr. Khim, Zh. , 23* 767-70 (1957) 13h. Klinayev, V. M. and Senyavin, M. M., "Separation of Spectrally Pure Cerium from Natural Mixtures by the Extraction Method," Primeneniye Mechenykh Atomov v Analit icheskoy Khimii, AN SSSR , 1955* 118-26 135. Nikolayev, A. ?.j Sorokina, A. A. and Maslennikova, A. S., "Extraction of Cerium with Tributyl Phosphate," Zh. Neorgan. Khimii , 3, I6O-6I4 (1958) 136. Gel'perin, N. I. and Liakumovich, A. G., "Extraction from Solutions," Khim. Nauka i Prom-st» 9 3, 725-35 (1958) 137 . Karpacheva, S. M.j Vasil'yev, V. A,; Dyadina, K. A. and Tsvetayev, A. A, "Tests on Extraction Columns with Forced Stirring," Khim. Prom-st', 1956, 358-63 138. Piterskikh, G. P. and Valashek, Ye. R., "Centrifugal Extraction," Khim. Prom-st ', 195?, 158-65- 139. Kagan s So Z., Aerov, M. E„° V lkova, T. S. and Vostrikova, V. N., "Investigating Extraction Apparatuses with Mechanical Mixing of the Phases," Khim. Prom-st 8 , 1958 , No. 7 5 1*32-38 II4O. Gel "per in, N. I. and S. A. Vil'nits, "Dispersion of Liquids Flowing Through Nozzles into Air and Liquid Media," Trudy Moskovskogo Insti- tuta Tonko y Khim ichesko y Tekhnologii im. M. V. Lomonosova j, 1956 , No7~6^ - lil^l5 lhl. Gel'perin, N. I.| Volynets, M, P. and Kolosova, G. M«, "Extraction Column," Khim. Nauka i Prom-st', 1, 560-63 (1956) lh2. Gel'perin, N. I.| Liakumovich, A. G. and M. V. Listopadov, "Extraction from Solutions in a Counter current Injector Column," Nauchyye Doklady. Vysshey Shkoly. Khimiya i Khimicheskaya Tekhnologiya , 1958, No. 1, 193-98 " 1U3. Karpacheva, S. M.j Khorkhorina, L. P. and Medvedev, S. F., "New Designs of Nozzle (injector) Extraction Columns," Atomnaya Energiya, 2, No. 6, 558-61 (June 1957) II4J4.. Gel'perin, N. I.| Krokhin, N„ G. and Kiseleva, Ye. N., "Extraction from Solutions with a Condensed Volatile Extracting Agent," Zh. Prikl a Khimii, 31, 1026-36 (1958) -98- 1US>. Gel'perin, N. I, and Kravchenko, I. I., "An Extraction Column with Alternating Mixing and Packed Sections," Khim. Mashinostroyeniye, 1959, No. 1, 28-32 Ili6. Kafarov, V. V. and Zhukovskaya, S. A., "Basic Characteristics of Injectors and Their Comparative Effectiveness as Extractors," Zh. Prikl. Khimii, £1, 376-86 (1958) lii7« Kafarov, V. V., "Extraction Column for Liquid-Liquid Systems, USSR Patent No. 117,778 (February 20, 1959) ll|8. Filippov, I. V., "Purification of Phenol Containing Weste Waters," USSR Patent No. 107,619 (September 25, 1957) Hi 9. Galkin, N. P.; Tikhomirov, V. A.; Goryaynov, N. le. and V. D. Fedorov, "Mechanism of Dispersion of Liquids in Plate Extractors and a Method of Increasing the Degree of Dispersion," Atomnaya Energiya , 7, No. 2, 159-60 (August 1959) 150 „ Planovskiy, A. N. and Bulatov, S. N., "On the Problem of Experimental Determination of the Drop Size During Investigations of Extraction Columns with Filter Plates, " ^auchnyye Doklady Vysshey Shkoly. Khimiya i Khimicheskaya Tekhnologiya, 1958 , No. U, r 8dJ4-09 151. Skryabin, A. K. "The Extraction Process," Zh. Fj z . Khimii , 33, No. 1, 7U-77 (1959) 152. Salamatov, I. I. and Veksler, G. M., "A Rotary Continuous Counter- Current Extractor," Khim. Mashinostroyeniye, No. 1, 12-lU (January 1959) -99- Appendix A Key to Journal Abbreviations Dokl. AN SSSR Doklady Akademii Nauk SSSR Dopovidi AN UkSSR Dopovidi Akademiy Nauk Ukrayins * koyi Radyans'Koyi Respubliki Izv. AN BSSR Izvestia Akademiya Nauk Belorusskoy Sovetskoy Sotsialisticheskoy Respubliki lav. AN SSSR. Otd. Khim. N. Izvestiya Akademii Nauk SSSR. Otdeleniye KhimibHeakikh Nauk Izv. AN SSSR. Otd. Tekhn. N* Izvestiya Akademii Nauk SSSR. Dtdeleniy© Tekhnicheskiy Nauk Izv. AN SSSR. Ser. Fizicheskaya Izvestiya Akademii Nauk SSSR. Seriya Fizicheskaya Izv. Sektora Fiz.— Khim. Analiza IONKh, AN SSSR Izvestiya Sektora Fiziko—Khimicheskogo Analiza, Akademiya Nauk SSSR, Institut Obshchey i Neorganicheskoy Khimii imeni N. S. Kurnakova J. Appl. Cheme (USSR) Journal of Applied Chemistry (USSR) J. Phys. Chem. (USSR) Journal of Physical Chemistry (USSR) J. Phys. (USSR) Journal of Physics (Academy of Sciences USSR) (Continuation of Technical Physics of the USSR. Apparently suspended with 11, No. 5, 19h7) Khim. Mashinostroyeniye Khimicheskoe Mashinostroyeniye Khim. Nauka i Prom-st' Khimicheskaya Nauka i Promyshlennost" Khim. Prom-st" Khimicheskaya Promyshlennost 5 Khimiya i Khim. Tekhnol. Sokr. Perev. iz In. Period. Lit Khimiya i Khimicheskaya Tekhnologiya. Sokrashchennyye" Perevody iz Inostrannoy Periodicheskoy Literatury Khimiya i Tekhnol. Topliv i Masel Khimiya i Tekhnologiya Topliv i Masel =100. Kolloidm Zhi Kolloidnyy Zhurnal Metody Issledovaniya Struktury Vysokodispers. i Poristykh Tel, AN SSSR, Tr. Soveshchaniya Metody Issledovaniya Struktury Vysokodispersnykh i Poristykh Tel, Akademiya Nauk, Trudy Soveshchaniya Quart. Revs. (London) Quarterly Reviews (London) Ref„ Zh. Khimiya Referativnyy Zhurnal - Khimiya Reports at the First Conference on Crystal Growth, £-10 March 1°£6 Growth of Crystals (Rost Kristallov), Reports at the First Conference on Crystal Growth, 5-10 March 19£6, in English translation, Consultants Bureau, ,Inc, New York, New York Sakharnaya Prom-st r Sakharnaya Promyshlennost 1 Sb. Fiz.-Matem. Fak. i N.-I. In-ta Fiz. (Odessk. Un-t) Sbornik Fiziko-Matematicheskogo Fakul'teta i Nauchno-Issledovatel'skogo Instituta Fiziki (Odesskiy Gosudarstvenny Universitet imeni I, I, Mechnikova) Tr. In-ta Chernoy Metallurgii. AN UkSSR Trudy Instituta Chernoy Metallurgii, Akademiya Nauk Ukrainskoy SSR Tr. In-ta Fiziki. AN UkSSR Trudy Instituta Fiziki, Akademiya Nauk Ukrainskoy SSR Tr. Ln-ta Kristallogr. AN SSSR Trudy Instituta Kristallograf ii, Akademiya Nauk SSSR Tr. Komis. po Analit. Khimii. AN SSSR Trudy Komissi po Analiticheskoy Khimii, Akademiya Nauk SSSR, Institut Geokhimii i Analiticheskoy Khimii imeni V. I. Vernadskogo Tr. Leningr. Tekhnol. In-ta im. Lensoveta Trudy Lenigradskogo Tekhnologicheskogo Instituta imeni Lensoveta Tr. Mosk. Khim. -Tekhnol. In-ta im. D. I. Mendeleyeva Trudy Moskovskogo Ordena Lenina Khimiko-Tekhnologicheskogo Instituta imeni D. I. Mendeleyeva Tr. Radievogo In-ta im. V. G. Khlopina Trudy Radievogo Instituta imeni V. G. Khlopina -101- Tr. Vses. N.-I. In-t Sakharn. Prom-sti Trudy Vsesoyuznyy Nauchno-Issledovatel'skiy Institut Sakharnoy TPronsyshlenncfsti Uch. Zap, Kishinevsk. Un-t Uchenyye Zapiski, Kishinevskiy Gosudarstvennyy Universitet Uch. Zap. LGU Uchenyye Zapiski Leningradskogo Gosudarstvennogo Universiteta imemi A. A. Zhdanova Uch. Zap. MGU Uchenyye Zapiski, Moskovskiy Ordena Lenina Gosudarstvenny Universitet imeni M. V. Lomonosova Ukr. Khim. Zh Ukrainskiy Khimicheskiy Zhurnal Vestn. AN SSSR Vestnik Akademii Nauk Vestn. Leningr. Un-ta, Ser. Fix i Khimii Vestnik Leningradskogo Universiteta, Seriya Fiziki i Khimii Zh. Analit. Khimii Zhurnal Analit ic he skoy Khimii Zh-. Eksperim. i '"Teqr. Fiz» Zhurnal Eksperimental'noy' I Te ore tic he skoy Fiziki Zh*. Fiz. Khimii Zhurnal Fizicheskoy Khimii Zh c . Ne organ .Khimii Zhurnal Neorganicheskoy Khimii Zh*. Obshch.* Khimii Zhurnal Ob she hey Khimii Zh«. Prikl.- Khimii' Zhurnal Prikladnoy Khimii Zh«. Tekhn. Fiz". Zhurnal Tekhnicheskoy' Fiziki 7'-, 'ry.vv.-, y-] ,y ■ ■ ■■ [ ;'c \ y hr, ' c-'< <:-}'x ' i; •/.-) 3 ± :'^:iki -102- Appendix B PRINCIPAL SOVIET AUTHORS ON MASS TRANSFER RESEARCH AND DEVELOPMENTS Author No. oi Refs. Cite'd Institute Specialty Ganz, S. N. 8 Absorption Dnepropetrovsk Chemical Technology Institut imeni F. E. Dzerzhinskiy Processes, equipment Kafarov, V. V. 8 Moscow Institute of Chemical Technology imeni D. I. Mendeleyev Theory, calculation methods Kishinevskiy, M. Kh. 17 Kishinev State University Theory, rates Kuz'minykh, I. N. 5 Moscow Institute of Processes Plit, I..G. Pozin, M. Ye. 11 Chemical Technology imeni D. • I. Mendeleyev Dnepropetrovsk Chemical Technology Institut imeni F. E. Dzerzhinskiy Leningrad Technological Institute imeni Lensovet Processes Theory, rates Adsorption Avgul', N. N. 1$ Moscow State University M. V. Lomonsov imeni Calo rime try, T he rmodynami c s Balandin, A. a. 15 Moscow State University imeni M. V. Lomonosov Adsorption in catalysis Bering, B. P. 15 Institute of Physical Chemistry, Academy of Sciences USSR Thermodynamic s Bykov, V. T. 8 Far Eastern Affiliate imeni V. L. Komarov, Academy of Sciences USSR Adsorbent structure (clays and earths) Dubinin, M. M. 38 Sorption Processes Laboratory, Institute of Physical Chemistry, Academy of Adsorbent structure (carbon) Sciences USSR -103- > y "j 1i m i. — I Bi n* ■ i ia ^»g*^ .* pil. r i.«M U i»i « 1 . —ia M fim Author No. of Refs. Cited Institute Specialty i Kiselev, A. V. Lyashcnko, V. I. Neymark, I. Ye. Rubinshteyn, A. M. Serpinskiy, V. V. Shlygin, A. I. Timofeyev, D. P. Vol'kenshteyn, F. F. Zaverina, Ye. ®. Zhdanov, S. P. 57 Moscow State University imeni M. V. Lomonosov 8 Institute of Physics, Academy of Sciences Ukrainian SSR 18 Institute of Physical Chemistry imeni L. V. Pisarzhevskiy, Acadengr of Sciences Ukrainian SSR 8 Institute of Organic Chemistry imeni N. D. Zelinskiy, Acadeny of Sciences USSR Ik Institute of Physical Chemistry, Academy of Sciences USSR 8 Moscow State University imeni M. V. Lomonosov 13 Institute of Physical Chemistry, Academy of Sciences USSR 13 Institute of Physical Chemistry, Academy of Sciences USSR 11 Institute of Physical Chemistry, Academy of Sciences USSR 10 Institute of Chemistry of Silicates, Academy of Sciences USSR Adsorbent structure (silica gel), adsorbent mechanism Chemisorption on semi- conductors Adsorbent structure (silicates) Adsorption in catalysis Thermodynamic s Adsorption at electrodes Adsorption kinetics Chemisorption Equilibria Adsorbent structure (Porous glasses) 'i r -10U- Author No, of Institute Refs, Cited Specialty Crystallization Danilov, V. I. 12 deceased Growth theory Gorshteyn, G. I. $ All -Union Institute of Chemical Reagents Growth from solutions Kamenetskaya, D. S. h Institute of Metal Studies Nucleation and Kapustin, A. P. Lemmleyn, G. G. Makarov, Ye. S. Petrov, D. A. Pozdnyakov, P. G, Savitskiy, Ye. M, Sheftal', N. N. Silant'yeva, N. I and Metal Phsyics, Central Scientific Research Institute of Ferrous Metallurgy . Institute of Crystallography, Academy of Sciences USSR Institute of Crystallography, Academy of Sciences USSR Institute of Geochemistry and Analytical Chemistry imeni V. I. Vernadskiy, Academy of Sciences USSR Institute of Metallurgy imeni A. A. Baykov, Academy of Sciences USSR Central Scientific Research Laboratory of Piezoelectricity, Ministry of Electric Power Stations and Electrical Industry Institute of Metallurgy imeni A. A. Baykov, Academy of Sciences USSR Institute of Crystallography, Academy of Sciences USSR All -Union Institute of Chemical Reagents growth Effects of ultrasonics Dendritic crystallization Crystal structure Growth from melts Growth from solutions Metal recrystalliza- tion Growth mechanism, single crystal techniques Growth from solutions -105- Author No. of Refs. Cited Institute Specialty Alabyshev, A. F. Byk, S. Sh. Gel'perin, N. I. Kafarov, V. V. Krupatkin, I. L. Lantratov, M. F. Morachevskiy, A. G, Rozen, A. M. Storonkin, A, V. Vdovenko, V. M. Extraction 7 Leningrad Polytechnical Institute imeni M. I. Kalinin 5 Scientific Research Institute of Synthetic Alcohols and Organic Products 7 Moscow Institute of Fine Chemical Technology imeni M. V. Lomonosovoc 8 Moscow Institute of Chemical Technology imeni D. I. Mendeleyev 20 Yaroslavl Technological Institut or Ivanovo Chemical Technology Institut 5> Leningrad Polytechnical Institut imeni M. I. Kalinin 6 Leningrad State University imeni A, A. Zhdanov 5? Instute of Physical Problems imeni S. I. Vavilov 11 Leningrad State University imeni A. A. Zhdanov 15 Institute of Radium imeni V. G, Khlopin, Academy of Sciences, USSR Fused salt systems Solubility by equilibria Extraction equipment Theory Liquid Phase Stability Fused salt systems Thermodynamics Uranium Extraction, The rmodynamic s Thermodynamics Uranium and fission product extraction; analytical application -106- Table RECENT SOVIET STUDIES OF EXTRACTION EQUILIBRIA System Benzene - formamide - acetone Benzene - formamide - diethylformamide Phenol » antipyrine - ligroine Phenol - isopropylbenzene - methyl styrene Water - acetic acid - benzene, toluene, xylene, diethyl ether, ethyl acetate, butyl acetate Water - aniline - aniline hydrochloride Water - antipyrine - chloral hydrate Water • «= £ - caprolactam - chloroform, dichloroethane, methylene chloride Water - ethanol - benzene Water - isopropanol - chloroethane Water - isopropanol - chloroform, carbon tetrachloride Water - methanol - dichloroethane Water - methanol - hexane, heptane, octane, nonane Water = phenol - anthranilic acid Water - phenol - antipyrine Water - phenol, methyl ethyl ketone Water «= phenol, methyl styrene Water - phenol - triethylamine Water - phenylene diamine - resorcinol Water - pyridine - chloral hydrate Water - quinoline - aniline Water - quinoline - diethyl ether Temperature (oC) 25 25 25-120 k$ 20, k0, 60 and boiling 25 60-190 35 - 65 25 25 25 10, 20 60- 65 25-120 20, h$, 75 20, a5 s 70 15, 35 20-120 20-120 15-1U0 15-11*0 -107- Table <(cont.) System Water - salicylic acid - aminopyrine Water - slaicylic acid - anthranilic acid Water - salicylic acid - gasoline Water - salicylic acid - phenol Water - salicylic acid - picric acid Water - dioxane - HC1, H 2 SO^, KC1, LiCl Water - ethanol - ammonium hydrogen fluoride Water - ethanol - sodium fluoride Water - methanol - calcium chloride Water - hydrochloric acid - molybdenum chloride complexes - butanol, iso-butanol, iso-pentanol, butyl formate, ethyl acetate, diethyl oxalate Water - - dibutyl ether - uranyl nitrate Water - diethyl ether - uranyl nitrate Water - nitric acid - plutonium, uranyl nitrates- tributyl phosphate Water - nitric acid - plutonium (IV) nitrate- tributyl phosphate (benzene, toluene, kerosene, freon, carbon tetrochloride) Water - nitric acid - plutonium (IV) nitrate - tributyl phosphate (benzene) Water - nitric acid - thorium nitrate - tributyl phosphate (benzene) Water — nitric acid - uranyl nitrate - tributyl phosphate (dibutyl ether, kerosene) Temperature (ScT 60-170 80-100 25-100 25 0,2$ 15-25 25 15 Table (conto) System Molten Salt Systems; Si0 2 - A1 2 3 -MF 2 (M- Ba, Ca, Mg, Sr) Si0 2 - MO - NF 2 (M= Ba, Mg, Sr) Si0 2 - NaF -MF 2 (M= Ba, Ca, Mg, Sr) Si0 2 - KF - CaF 2s MgF 2 Si0 2 - Na 2 -CaF 2 Tl Br - KM03-AgCl, LiCl, MaCl, BeSO, , Na 2 SO. -109-= USCOMM-DC PENN STATE UNIVERSITY LIBRARIES imiiiiiiii AQ000712fl7b5S