Balandin, Aleksey Aleksandrovich

(b. Yeniseysk, Siberia, Russia, 20 December 1898; d. Moscow, U.S.S.R., 22 May 1967)

chemistry.

Balandin was the founder of an important school of catalytic chemistry. He graduated from Moscow University in 1923. Professor of chemistry from 1934, he was elected a corresponding member of the Soviet Academy of Sciences in 1943 and a full member in 1946.

As a result of his quantitative studies of the kinetics of catalytic reactions of hydrogenation and dehydrogenation of cyclic hydrocarbons, Balandin established that two factors play a decisive role in all catalytic processes: (1) a similarity between the structure of the reacting molecules and the surface of the catalyst and (2) comparable energy values for the chemical bonds of the molecular reagents and the energy of chemical interaction of these molecules with the surface of the catalysts. In 1929 Balandin made this discovery the basis of his universal catalysis theory, which became known as the universal “multiplet” theory of catalysis.

For the first time in the history of chemistry, Balandin proposed and demonstrated physically the principle of an active transitional state

characterized by the formation of an unstable complex containing not fully valent chemical bonds (i.e., bonds with less than two electrons). With some modifications, this principle has been incorporated into one of the most universal theories of chemical processes, the of the absolute reaction rates.

Balandin showed that the active, or multiplet, complex (formed as a transition state in hydrogenation and dehydrogenation processes of cyclic hydrocarbons) can take on an orientation that conjoins either the plane or a facet of a molecule with the surface of the catalyst. The practical outcome of this work was that Balandin was able to predict catalytic activity for a number of metals in group VIII of the periodic table, as well as for chromium and vanadium oxides. Chromium sesquioxide later became a commercial–type catalyst.

Having worked out quantitative methods to determine a catalyst’s maximum activity, Balandin showed that the peak activity is located in the vicinity of an adsorption potential, q, equal to one half of the total energy of the reacting bonds, s, i.e., at the q = s/2 point. This relationship gives a solution to the problem of selecting catalysts by experimental determination of their absorption potential. In addition, Balandin determined the conditions for enhancing the activity of mixed catalysts and found explanations for poisoning–promoting and utilizing these conditions in the control of the activity. He was thus able to forecast the sequence of reactions in stepwise processes.

On the basis of the multiplet theory, Balandin proposed a classification of the organic catalytic reactions that reflected the positions of the atoms in the reacting molecule on the catalyst surface in relation to the active center. The importance of this classification for catalytic organic synthesis is equivalent to that of the system of forms used in crystal–lography. New types of processes can be forecast by means of this system of classification. For example, in 1935 Balandin predicted the then unknown types of paraffin and olefin dehydrogenation processes that now form the basis for the production of monomers used in the synthesis of rubber.

Balandin introduced a number of basic concepts and ewuations into chemical kinetics. In 1929-1930 he was one of the first (together with F. Constable) to indicate the importance of activation energy determinations in the study of heterogenous processes; he established a logarithmic dependence between e and k₀ in the Arrhenius equation k=k ₀. e ^{- e/rt} (∊ being the empirical value of activation energy). In 1930-1935 he gave a precis equation of reaction kinetics in a flow system and derived a general equation for monomolecular reactions complicated by adsorption equilibrium. Having studied the kinetics of the dehydrogenation of butane and butylene to butadiene and of ethylbenzen to styrene, Balandin was the first to find conditions under which the yield of these most valuable monomers approached the thermodynamically feasible maximum.

Balandin’s work in catalysis is closely connected with petrochemical synthesis. Together with N. D. Zelinski and his aides, Balandin participated in the discovery and study of the alkane and cyclane (cyclo–paraffin) reactions and, in particular, in the dehydrocyclization of paraffins, aromatization, and hydro–genolysis. In 1950 he applied the multiplet theory to fermentation processes, demonstrating the special role of the matrix effect by imposing substituents on the surface of ferment (entropy factor) and by lowering the potential barrier of the reaction and of the heat of adsorption (energy factor).

BIBLIOGRAPHY

I. Original Works. Among Balandin’s writings are “Khimiya i struktura” (“Chemistry and Structure”), a series of articles in Izvestiia Akademii nauk SSSR (1940), 295–310; (1940), 571–584; (1942), 168–178, 286–296; (1943), 35–42; “Teoria slozhnykh reaktsy” (“Theory of Complex Reactions”), in Zhurnal jizicheskoi khimii, 15 (1941), 615–628; “Tochny metod opredelenia adsorbtsionnykh koeffitsientov” (“A Precise Method of Determining Adsorption Coefficients”), in Izvestiia Akademii nauk SSSR (1957), 882–884; “Printsipy strukturnogo i energeticheskogo sootvetstvia v fermentativnom katalize” (“Principles of Structural Energetic Conformity in Fermentative Catalysis”), in Biokhimiya, 23 (1958), 475–485; and Multi–pletnaya teoria kataliza (“Multiple Catalysis Theory”), 2 vols. (Moscow, 1963–1965).

II. Secondary Literature. Works on Balandin are Materialy k biobibliografy uchenykh SSSR. Aleksey Aleksandrovich Balandin (“Bibliographical Material Concerning the Lives of USSR Scientists. Aleksey Aleksandrovich Balandin” Moscow, 1958); A. M. Rubin–stein, “Akademik Aleksey Aleksandrovich Balandin” (“Academician Aleksey Aleksandrovich Balandin”), in Uspekhi khimii, 18 (1949), 38 (issued on the occasion of his fiftieth birthday); H. S. Taylor, “Geometry in Heterogeneous Catalysis,” in Chemical Architecture (New York, 1948), pp. 8–18; and B. M. W. Trapnell, “Balandin’s Contribution to Heterogeneous Catalysis,” in Advances in Catalysis and Related Subjects, III (New York, 1951), 1–25.

V. I. Kuznetzov