Methanation of Carbon Dioxide on Ni(100) and the Effects of Surface Modifiers

Article abstract of DOI:10.1021/j100245a014

The methanation of CO2 over Ni(100) was studied with H2/CO2 ratios of 4/1 and 96/1 (total pressures of 120 and 97 torr) for temperatures between 450 and 750 K.Large amounts of CO were formed, with activation energies of 21.2 and 17.4-19.7 kcal mol^-1 for CH4 and CO formation, respectively.The absolute CH4 production rates were very close to those seen seen for methanation of CO.These results support a mechanism with CO and C(a) intermediates.Adsorption of K and/or S resulted in changes in the amounts and rates of CH4 and CO production, but no change in activation energy.Results showed that the effects of K(a) can compensate for the effects of S(a), and support electronic interaction as responsible for poisoning/promotion effects.