Influence of CO2 Reforming of CH4 Reaction Performance by Adding Vapor on Ni/CeO2-ZrO2-Al2O3 Catalyst

The Ni/CeO2 -ZrO2 -Al2O3 catalyst was prepared with the hydrothermal method. The catalytic performance for the CO2 reforming of CH4 reaction with or without small amount of steam was tested and the amount of coke deposition was measured. The XAFS of Ni K-edge was attained. The results show that the formation of CeAlO3 occurs in reaction，but the coke deposition is responsible for the deactivation of the catalyst. The addition of steam into feed gas can decrease the amount of coke deposition，and promote the stability. Due to the carbon atom penetration into the Ni lattice，for the catalyst sample after reaction without the addition of steam into feed gas，the coordination number of the first Ni-Ni shell decreases sharply. For the catalyst sample after reaction with the addition of steam in feed gas，the coordination numbers of the first Ni-Ni shell decrease slightly. It is due to the addition of steam into feed gas，which can suppress the coke formation and maintain the metallic structure of active Ni metal.