Yttrium-stabilized zirconia-promoted metallic nickel catalysts for the partial oxidation of methane to hydrogen

A metallic Ni catalyst has been prepared with nickel sponge and further promoted with YSZ (yttrium-stabilized zirconia) by an impregnation method. The catalysts are characterized by ICP, BET, SEM, XRD and H-2-TPR, and then studied for the partial oxidation of methane to hydrogen. The influences of reaction temperature, CH4/O-2 ratios and gas hourly space velocity on the reaction rate are investigated. The catalyst characterization results show that the YSZ-promoted metallic Ni catalysts have high specific surface area; there is more NiO phase in the YSZ-promoted catalysts than in the metallic Ni catalyst; a mutual diffusion of Ni2+ and Zr4+ ions might happen between the NiO and YSZ phases. The reaction results show that the YSZ promotion increases the CH4 conversion and the selectivities to H-2 and CO. (C) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.