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 1342.    HAMAI, S.  Physicochemical Investigations of Catalytic Mechanisms.  I.  Fischer-Tropsch Synthesis of Hydrocarbons With Special Reference to Its Mechanisms.  Jour. Chem. Soc. Japan, vol. 62, 1941, pp. 516-518; Chem. Abs., vol. 37, 1943, p. 4681.

        In the Fischer-Tropsch synthesis of hydrocarbons the catalyst acts as a carrier, as ascertained in 350 experiments.  With Co the catalytic mechanism is as follows:  Co adsorbs CO on its surface, and the CO is hydrogenated to CHOH, CoCHOH by catalytic reduction is changed into CoCH₂ and H₂O.  In the beginning when the amount of CoCH₂ is small as compared with that of H₂, CH₄ is formed by the reaction CO+3 H₂=CH₄+H₂O (particularly when CO:H₂ is greater than 1:3) or at 300° CH₄ results from the reaction CoCH₂+H₂=CH₄+Co.  However, at the later stage of the reaction or at 200° CH₄ not formed.  The CoCH₂ then polymerizes into Co(CH₂)_n, which further separates into Co and (CH₂)_n, the hydrogenation of the latter resulting in a high hydrocarbon (liquid).  This catalytic mechanism was found with Fe and Ni.  In the case of Fe (synthesis carried out at 250°), however, CO₂, instead of H₂O, was obtained after the catalytic reduction owing to the presence of the rapid reaction CO+H₂O=H₂+CO₂.