Oxygen‐vacancy‐driven Ni catalyst enables energy‐efficient industrial methanation at low temperatures

Abstract The targeted design of promoter–support interactions in Ni catalysts is pivotal yet challenging for achieving highly active low‐temperature CO/CO 2 methanation under mild conditions. We address this by developing a series of Sm 3+ , La 3+ , and Pr 3+ doped Ni–MgO–CeO 2 –Al 2 O 3 catalysts via an ultrasound‐assisted co‐precipitation method. The optimized Sm 3+ modified catalyst exhibited exceptional performance, featured by maximal oxygen vacancy concentration and enhanced metal–support interactions that facilitated CO and CO 2 adsorption/activation. This catalyst achieved 100% CO conversion and 95% CO 2 conversion with >97% CH 4 selectivity at 275°C and 15 bar. In situ FT‐IR studies reveal the mechanism involving key formation of oxygenated intermediates and hydrogenation. Critically, the catalyst demonstrated outstanding stability over 200 h in real‐world CO 2 ‐supplemented coke oven gas methanation. Integrating this catalyst, we further proposed a two‐stage reactor system that directly produced pipeline‐grade methane (89.9%), significantly reducing capital expenditure and energy consumption for industrial coal‐to‐gas applications.