Transition Metal (Ni, Cu, Ga, Fe) Doped Lacoo3 Improve Surface Hydrogen Activation to Promote Low-Temperature Co2 Methanation

The LaCo 0.7 X 0.3 O 3 (X=Co, Ni, Cu, Ga, Fe) perovskite catalyst was prepared by the sol-gel method, and the effect of the partially substituted catalyst at the B-site for the hydrogenation of CO 2 to methane reaction was studied. XRD, H 2 -TPR, TEM, BET, CO 2 -TPDand XPS technologies were used to characterize the catalyst. It was found that the reduction ability of LaCoO 3, the specific surface area and surface defects of the material could be enhanced with the B-site element doping, the dissociation ability of H 2 also be improved for the CO 2 methanation reaction. The catalyst dissociates more H* radicals and combines with the CO 2 adsorbed on the La site to form HCOO*, then hydrogenates to form H 2 CO* and removes H 2 O, and finally hydrogenates to form CH 4 . The CO 2 conversion rate and CH 4 yield of the doped catalyst have been significantly improved. At 220℃-280℃, the CO 2 conversion rate can reach 13%, and the highest CH 4 selectivity can reach 99%