Abstract: A series of Ni/SBA-15 catalysts with different Ni contents (2.5% to 20%) were prepared by an incipient wetness impregnation method. The catalytic properties of the catalysts for the methane reforming with carbon dioxide were tested with a continuous-flow fixed-bed quartz reactor. The structure of the catalysts was characterized using X-ray diffraction and N2 adsorption. The results indicated that Ni/SBA-15 catalysts had a higher conversion of CH4 and CO2 under the reaction conditions. The 12.5%Ni/SBA-15 catalyst showed highly stable activity at 800 ℃ for 600 h. However, after reaction of 710 h, the conversion of CH4 and CO2 decreased about 50% and 25%, respectively. Coking was the main reason for the deactivation of Ni/SBA-15 catalysts. At high reaction temperatures, the mesoporous structure of SBA-15 was not destroyed and the pore walls of SBA-15 could prevent the aggregation of the nickel species. Upon insertion of nickel into SBA-15, small pores were formed besides the mesopores of SBA-15. The mesoporous structure of SBA-15 was not affected by the nickel species, however, the pore diameter, pore volume, and BET surface area were decreased.

Key words: nickel, SBA-15 zeolite, methane, reforming, carbon dioxide, syngas