Density Functional Theory and Kinetic Studies of Methanation on Iron Surface

The production of methane from CO and H 2 on a clean Fe(100) surface was studied using periodic DFT calculations in conjunction with kinetic modeling. It was found that the adsorption and subsequent dissociation of CO and H 2 at a finite temperature are significantly influenced by the presence of coadsorbed CO and H. The surface coverage of CO is controlled by entropy, and a maximum of 50% coverage can be attained. The kinetic modeling adopting the computed activation barriers for the elementary steps involved in methanation revealed that CH is a major C 1 species on the surface. The production of CH 4 was found to be more favored at a high reaction temperature and H 2 partial pressure but suppressed by a high pressure of CO.