2196.     MATSUMURA, S., TARAMA, K., AND KODAMA, S.  Benzine Synthesis and Activated Adsorption of Hydrogen, Carbon Monoxide, Carbon Dioxide and Water on Cobalt and Iron.  I.  II.  III.  Sci. Papers Inst. Phys. Chem. Research (Tokyo), vol. 37, 1940, pp. 302-322 (in German); Jour. Soc. Chem. Ind. (Japan), vol. 43, suppl., 1940, pp. 175-184; Chem. Zentralb., 1940, II, p. 2842; Chem. Abs., vol. 34, 1940, pp. 6502-6503.

        Physical adsorption of H₂ on Co or Fe occurs below 60°; above this temperature activated adsorption occurs until a maximum is reached at approximately 200° (Co) or 160° (Fe).  Adsorption of CO by Co or Fe, although equilibrium is approached slowly, increases rapidly above 60°, the adsorption being reversible below 110° (Co), but decreases above 60° for Fe, adsorption increasing above 190°.  Chemisorption of CO by Co or Fe probably results in carbide formation, Fe requiring a higher temperature for this process.  Adsorption of CO₂ by Co is considerable; physical adsorption probably occurs below 100° and activated adsorption above 100°, with a maximum at 150°.  Fe adsorbs considerable CO₂ at room temperature, but this adsorption decreases to a negligible amount at 300°.  Co and Fe exhibit physical adsorption of N, adsorption virtually ceasing at 100° (Co) and 250° (Fe).  Subtraction of the values on the adsorption curve for N on Co or Fe from those on the curve for wet N indicates roughly that activated adsorption of H₂O on Co starts about 60° and reaches a maximum at 100° and that for Fe activated adsorption begins at 200°.  In the benzine synthesis, a carbide is first formed, which reacts with adsorbed atomic H to give CH₂ groups; these CH₂ groups undergo polymerization (various degrees depending on number of groups present), then reduction, and the hydrocarbons so formed volatilize from the catalyst surface.  Temperatures above 160° for the synthesis of benzine with Co catalyst are necessary so that enough quantities of activated H₂ will be adsorbed on the catalyst.  A higher reaction temperature is required with Fe on account of higher temperature of formation of Fe carbide.  In the benzine synthesis, Co differs in its action from Fe in that H₂O instead of CO₂ is formed because of the greater desorption velocity of H₂O from the Co.