Mechanistic study of methane reforming with carbon dioxide on a supported nickel catalyst

The nature of activation of methane on supported nickel catalyst has been investigated by means of temperature programmed surface reaction (TPSR), temperature programmed desorption (TPD), X-ray photoelectron energy spectroscopy (XPS) and pulse reaction and a synergetic mechanism of carbon dioxide reforming with methane is tentatively postulated. TPSR, TPD and XPS results indicate that carbidic C-alpha, carbonaceous C-beta and carbidic clusters C-gamma surface carbon species formed by decomposition of methane show different surface mobility, thermal stability and reactivity. C-alpha and C-beta species on the nickel surface are thermally unstable and can be rapidly converted into C-gamma species upon increasing temperature. The carbidic carbon is a very active and important intermediate in carbon dioxide reforming with methane and the carbidic clusters C-gamma species might be the precursor of the surface carbon deposition.