Dry reforming of methane over Ni catalysts supported on micro- and mesoporous silica

Worsening global warming and the proposition of carbon neutrality brings new challenge to the utilization of carbon dioxide. Dry reforming of methane draws much attention among various utilization routes due to its high efficiency. In this work, mesoporous silica support SBA-15 and microporous silica support beta were applied to the Ni catalysts for the dry reforming of methane. Compared with the impregnated catalyst Ni/SBA-15, highlydispersed Ni nanoparticles were obtained on Ni-SBA-15 and Ni-beta catalysts prepared by ammonia evaporation method, and they performed excellent catalytic activity, with a CO2 conversion of ca. 89 % and a CH4 conversion of ca. 84 % at 700 degrees C and nearly 100 % conversions at 800 degrees C. Benefited from the confinement of the mesopores, Ni nanoparticles were well embedded in the pores of Ni-SBA-15 and exhibited distinguished resistance to Ni sintering and carbon deposition. Ni-beta suffered relatively more intensive Ni sintering and carbon deposition because the pore size of beta was much smaller so that it was difficult to introduce Ni into its micropores by ammonia evaporation method.

Automated summary

Dry reforming of methane is an efficient way to utilize carbon dioxide. This study utilized mesoporous silica support SBA-15 and microporous silica support beta as catalyst supports, and obtained highly dispersed Ni nanoparticles on Ni-SBA-15 and Ni-beta catalysts prepared by ammonia evaporation method. The Ni-SBA-15 and Ni-beta catalysts showed excellent catalytic activity, with a CO2 conversion of ca. 89 % and a CH4 conversion of ca. 84 % at 700 degrees C and nearly 100 % conversions at 800 degrees C. The mesopores of SBA-15 provided confinement for Ni nanoparticles, preventing Ni sintering and carbon deposition. However, the smaller pore size of beta hindered the introduction of Ni into its micropores, leading to more intensive Ni sintering and carbon deposition.