786.    ---------------.  [EIDUS, Y. T.]  [Investigation of Catalysts for Hydrogenation of Carbon Monoxide by Simultaneous Application of the Dynamic and Static Methods.  IV.  Kinetics of Carbide Formation and of Hydrogenation of Carbon Monoxide on Co, Ni, and Fe Catalysts.]  Bull. Acad. Sci. U.R.S.S., Classe Sci. Chim., 1946, pp. 447-453; U>O>P> Co. Survey Foreign Petroleum Literature Transl. 656, 1946, 7 pp.; Chem. Abs., vol. 43, 1949, p. 6063.

     By the simultaneous application of the dynamic and static methods, a comparative study was carried out of the kinetics of hydrogenation of CO and of the interaction of the latter with the surface of Co-Th-marshallite catalysts (100:18:100), of Ni-Mn-Al-marshallite (100:20:10:100), and of Fe-Cu-Th-K2CO3-marshallite (100:25:2:2:125).  With the Co and Ni catalysts, the reaction temperatures were 180-210 with a gas mixture 1 CO:2 H2; in the case of Fe catalyst, 230-260 and 1 CO:1 H2.  The carbide formation and the hydrogenation of CO were studied at identical temperatures in the same catalytic furnace.  The kinetic data obtained show that the ratio of the initial velocities of hydrogenation of CO to the carbide formation is much lower in the case of the Fe catalyst than for the Co and Ni catalysts.  The lower ratio for the Fe catalyst results from the reduced hydrogenation velocity of CO on this catalyst as compared with the velocity of this process on the Co and Ni catalysts.  This is in agreement with the carbide theory of synthesis of hydrocarbons from CO and H2.  ON Co and Ni catalysts, the rate of hydrogenation of CO materially exceeds that of interaction of CO with the catalyst, which contradicts the carbide theory of catalytic synthesis of hydrocarbons from CO and H2 on these catalysts.  If formation of liquid and solid hydrocarbons by hydrogenation of CO involves the carbide mechanism

            (1)              2CO→CO2+C(carbide) (a)

            (2)              C(carbide) + H2→CH2   (b)

                               2CO+H2→CO2+CH2    (c)



then the conclusion can be drawn from the experimental data obtained that equality of the reaction velocities of (a) and (c) is in accord with the carbide theory only in the case of Fe catalysts; for the Co and Ni catalysts, the velocity of the process is considerably in excess of that in the process (a).  All this speaks against the applicability of the carbide-formation mechanism for the explanation of the chemical process occurring on the Co and Ni catalysts and in favor of this mechanism of synthesis of hydrocarbons from CO and H2 in the case of Fe catalysts.  This is also supported by data previously reported by the author.