CATALYTIC OXIDATION OF METHANE AT LOW TEMPERATURE OVER Ni-CONTAINING PEROVSKITE-TYPE OXIDES

摘要

Two types of catalysts with the same nickel loading, nickel-substituted perovskite La_(0.95)Ce_(0.05)Co_(0.6)Ni_(0.4)O3 and perovskite-supported nickel catalyst Ni/La_(0.95)Ce_(0.05)CoO3 were prepared by the combustion and impregnation method, respectively. The catalyst structure was characterised by X-ray diffraction (XRD), BET measurements, temperature-programmed reduction (TPR), and the methane oxidation activity of the catalysts was investigated in details. It was found that the activities of Ni/La_(0.95)Ce_(0.05)CoO3 and of La_(0.95)Ce_(0.05)Co_(0.6)Ni_(0.4)O3 do not change much and decrease sharply compared with La_(0.95)Ce_(0.05)CoO3, respectively. The surface area of the catalysts decreases sharply with the introduction of a large amount of nickel loading or nickel-substituted.