643.    CRAXFORD, S. R., AND RIDEAL, E. K.  Mechanism of the Synthesis of Hydrocarbons From Water Gas.  Jour. Chem. Soc., 1939, pp. 1604-1614; British Chem. Abs., 1940, B, p. 8; Chem. Abs., vol. 34, 1940, p. 1464.

      Experiments on the rates of formation and reduction of Co₂C on Co-Th-kieselguhr catalysts under various conditions indicate that the first step in the Fischer-Tropsch synthesis of hydrocarbons from CO and H₂ is the reaction of these gases with the catalyst to give Co carbide.  As indicate by the o-p-H₂ conversion, when carbide is reduced only CH₄ is formed and no higher hydrocarbons.  Reduction by H₂ leads to formation of oils.  Curves are given for the rates of the reactions between Co and CO, between Co₂C and H₂ on the Fischer catalyst, for the energies of activation of the reaction Co₂C+2H₂, and for the total reaction CO+2H₂.  It is concluded that, in order to obtain oils, the conditions of the synthesis have to be adjusted so that only very few chemisorbed H₂ atoms are present on the catalyst surface.