Performance of Ni/La2O3 catalyst in carbon dioxide reforming of methane to synthesis gas

Abstract

The rate of carbon dioxide reforming of methane over a Ni/La2O3 catalyst is found to increase during the initial 2–5h and then tends to be invariable with time on stream. A kinetic isotopic study shows that the reaction rate is reduced, by a factor of 1.2–2.0, upon switching the reactant mixture from CH4/CO2 to CD4/CO2, suggesting that methane activation is a slow step. Chemisorptive studies indicate that a portion of the Ni surface is decorated with lanthanum species originating from the La2O3 support, thus suppressing CO chemisorption and disproportionation. Mechanistic studies by FTIR, XRD, XPS and SIMS suggest that the interaction between nickel and lanthanum species creates a new type of synergetic sites at the Ni-La2O3 interfacial area, which offer active and stable performance of carbon dioxide reforming of methane to synthesis gas over the stated catalyst.