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 1343.    ---------------.  [HAMAI, S.] Physicochemical Investigations of Catalytic Mechanism.  II.  Fischer-Tropsch Synthesis of Hydrocarbons With Special Reference to Its Reaction Mechanisms.  Bull. Chem. Soc. Japan, vol. 16, 1941, pp. 213-228; Chem. Abs., vol. 36, 1942, p. 739.

        Following mechanism of the Fischer-Tropsch synthesis over a Co catalyst is proposed and discussed from the standpoint of energetics and thermodynamics:  CO is adsorbed or displaces H₂ adsorbed on the Co surface, forming Co-Co(-C=O)Co, which is reduced first by adsorbed H₂ to Co-Co(-HCOH)Co, then to Co-Co(-CH₂)Co.  The (CH₂) mol. adsorbed on the Co surface migrate freely over the surface to interact with one another to form Co-Co(-CH₂CH₂CH₂CH₂ . . . . . .)Co, which, upon desorption, yields (CH₂)_n and finally liquid products by hydrogenation.  At 20°, Co-Co(-C=O)Co does not form CH₄ by hydrogenation, but at 300° CH₄ is formed; CH₄ formation probably results from reaction of CO and H₂ in the gas phase.  Maximum adsorption does not necessarily coincide with maximum catalytic activity.  The same mechanism applies to Fe- and Ni-type catalysts.  If the catalyst is pretreated with CO at 350°, it suffers a loss of activity, possibly owing to prevention of adsorption of H₂ by the adsorbed CO.