Carbon dioxide reforming of methane over nickel-grafted SBA-15 and MCM-41 catalysts

Mesoporous molecular sieves SBA-15 and MCM-41 supported Ni catalysts were prepared via a post-synthesis grafting method. The catalytic properties of these catalysts were investigated in CO₂ reforming of CH₄ under atmospheric pressure and compared with the impregnated catalysts. Characterization using powder X-ray diffraction, N₂ physisorption, H₂ temperature-programmed reduction, TG/DTA, Raman spectra and transmission electron microscopy techniques revealed that both catalyst preparation method and the nature of support play important roles in controlling the catalytic performance. The highest catalytic activity and long-term stability were obtained over a 5 wt.% Ni-grafted SBA-15 catalyst. This superior catalytic behavior was closely related with the strong resistance toward carbon formation and active metal sintering. Furthermore, the improved properties of the catalyst was caused by the formation of highly dispersed small Ni particles anchored by silica matrix, rather ordered pore structure, and structural stability of SBA-15 material under reaction conditions.