Methane reforming over Ni/Ce-ZrO 2 catalysts: effect of nickel content

Abstract

The effect of Ni content on the Ni/Ce-ZrO 2 catalyst has been investigated in the methane conversion reactions to syngas, such as oxy-reforming, steam reforming and oxy-steam reforming. Among the catalysts examined, Ni/Ce-ZrO 2 catalyst with 15% Ni loading exhibits not only the highest catalytic activity and selectivity but also remarkable stability. The TPR results reveal that strong interaction between support and metal exists and that some part of NiO incorporates into the surface of the Ce-ZrO 2 support. Combined with H 2 chemisorption results, one may deduce that Ni surface area and the chemical environment of nickel, as well as the properties of the Ce-ZrO 2 support, play very important roles in the catalytic activity and stability of Ni/Ce-ZrO 2 catalysts. It seems that two kinds of active sites, i.e. one for methane and the other for steam or oxygen, are well-balanced on 15% Ni/Ce-ZrO 2 catalyst.