Mesoporous nickel catalyst supported on multi-walled carbon nanotubes for carbon dioxide methanation

Abstract

Nickel-based catalysts supported on multi-walled carbon nanotubes (CNTs) promoted with cerium were successfully synthesized by ultrasonic-assisted co-impregnation, using γ-Al2O3 as comparative support, and employed in the carbon dioxide methanation reaction. Results indicated that the exceptional properties of CNTs together with the accession of cerium effectively enhanced the dispersion of metallic nickel, promoted the reduction of metal oxides and accelerated the CO2 activation. Meanwhile, the confinement effect of CNTs and the promotion effect of cerium could efficiently prevent the active species migration and sintering, and restricted the carbon deposition reaction. Catalytic performances exhibited that 12Ni4.5Ce/CNT catalyst possessed the highest activity with 83.8% conversion of CO2 and almost 100% selectivity of CH4 without obvious deactivation after 100 h stability test under reaction conditions.