The role of MnO in Ni/MnO-Al 2O 3 catalysts for carbon dioxide reforming of methane

Abstract

Addition of manganese to Ni/Al 2O 3 improves the stability of the catalyst in CO 2 reforming of methane. The role of manganese has been investigated particularly in view of the deposition of unreactive carbon on the catalyst surface. Results of XRD, XANES, TEM and hydrogen chemisorption indicate that the surface of nickel is partly covered (“decorated”) by patches of MnO x . Manganese addition also promotes the adsorption of CO 2 by forming a reactive carbonate species. Both of these effects appear responsible for the suppression of carbon deposition over Ni/MnO-Al 2O 3.