Sacrificial Carbon Strategy toward Enhancement of Slurry Methanation Activity and Stability over Ni-Zr/SiO2 Catalyst

Mesoporous silica-supported Ni-Zr catalysts prepared via the modified impregnation method by applying different solvents and calcination atmospheres were employed for CO methanation in a slurry-bed reactor. The results show that the glycerol-impregnated Ni-Zr/SiO2 catalyst exhibited higher specific surface area and Ni species dispersion and more intensive nickel–support interaction than the water-impregnated one and thus enhanced the catalytic activity and stability. Furthermore, the carbon could be constructed on the surface of the Ni-Zr/SiO2 catalyst from the carbonization of glycerol via calcination under an inert atmosphere and be removed through successive calcination in air. Owing to the improved nickel–support interaction, the carbon-sacrificed Ni-Zr/SiO2 catalyst exhibited higher Ni dispersion and smaller and more uniform Ni particle sizes, leading to catalytic activity for CO methanation that is higher than that of the catalysts without carbonization.