258.    BINDER, G. G., AND WHITE, R. R.  Synthesis of Methane From Carbon Dioxide and Hydrogen.  Chem. Eng. Progress., vol. 46, No. 11, 1950, pp. 563-574.

                  Rate of formation of CH₄ from CO₂ and H₂ was measured by passing feed gas ranging in composition from 80% H₂ and 20% CO₂ to 30% H₂ and 70% CO₂ over a reduced Ni catalyst in a continuous apparatus.  Several runs were made in which the feed gas contained CH₄.  The space time was varied from 0 to 8 x 10^-5 hr.  The temperature range was 500°-750° F., and the pressure was maintained at 1 atm. in all runs.  Average rates of CH₄ formation, obtained by differentiation of the data, vary from 0-5.60 lb. mols./day (lb. catalyst).  Rate of reaction can be correlated by a mechanism that assumes that the major resistance to the overall process is offered by the reaction of an adsorbed CO₂ molecule with at least 2 adsorbed H₂ molecules.  Presents two equations for the rate of CH₄ formation resulting from the extremes of the range of correlating mechanisms.