2769.     RANDALL, M., AND GERARD, F. W.  Synthesis of Methane From Carbon Dioxide and Hydrogen.  Ind. Eng. Chem., vol. 20, 1928, pp. 1335-1340; Chem. Abs., vol. 23, 1929, p. 814.

        Equilibrium for the reaction CO₂+4H₂=CH₄+2H₂O was determined by the dynamic method at atmospheric pressure and at temperatures 322°-392.5°.  The catalysts used were supported Ni catalysts, both unpromoted and promoted by ceria.  Space velocities 6-12 were used.  Equilibrium was approached from both sides.  In studying the forward reaction, ratios of H₂:CO₂ of 4 and 2.3 were used.  The free-energy equation that fits the data for this reaction is ∆F°=-35,093+12.38 TinT-0.00415T²-0.00000025T³-39.91T.  This equation gives ∆H°_298.1+ -38.401 cal. and ∆F°_298.1= -26,339 cal.  An observed deposition of C during some of the experiments is accounted for by assuming reaction is thermodynamically possible under experimental conditions prevailing.