Enhancing low-temperature CO2 methanation via a dual anchoring impregnation strategy for highly dispersed Ni-Ce/SBA-15 catalysts

Background CO 2 methanation plays a critical role in reducing carbon emissions. The development of Ni-based catalysts with simple synthesis processes and low costs for low-temperature methanation demonstrates promising industrial application prospects, yet it also faces significant challenges. Ni-based catalysts generally require higher metal loadings, which in turn makes it difficult to achieve high metal dispersion, severely limiting their low-temperature catalytic activity. Methods In this study, a simple co-impregnation method was employed in combination with a dual-strategy approach: hydrogen peroxide pretreatment to increase the concentration of silanol groups on the SBA-15 silica support surface and the assistance of ethylene glycol (EG) during the impregnation process. Significant findings The significant finding of this work lies in the demonstrated synergy of a dual strategies to stabilize highly dispersed Ni catalysts for CO 2 methanation. While high dispersion and good low-temperature activity have been reported elsewhere, this study specifically shows that combining (1) ethylene glycol-assisted impregnation to improve initial dispersion with (2) the utilization of SBA-15 silanol groups as anchoring sites effectively mitigates sintering. This combined approach resulted in a catalyst achieving 77% CO 2 conversion and 100% CH 4 selectivity at 250 °C, with characterization confirming the enhanced stability afforded by the synergy.