Structural Characterization of Highly Stable Ni/SBA-15 Catalyst and Its Catalytic Performance for Methane Reforming with CO2

A series of Ni/SBA-15 catalysts with different Ni contents (2.5%–20%) were prepared using an incipient wetness impregnation method. The catalytic properties of the catalysts for methane reforming with carbon dioxide were tested using 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 the Ni/SBA-15 catalysts led to a higher conversion of CH4 and CO2 under the reaction conditions. The 12.5% Ni/SBA-15 catalyst showed highly stable activity at 800°C for 600 h. However, after reaction for 710 h, the conversion of CH4 and CO2 decreased by about 50% and 25%, respectively. Coking was the main reason for the deactivation of the Ni/SBA-15 catalysts. At higher 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. By inserting nickel into SBA-15, a small pore was formed besides the mesopores of SBA-15. The mesoporous structure of SBA-15 was not affected by the nickel species; however, the pore diameter, the pore volume, and the BET surface area decreased.