Abstract:  The methanation of carbon dioxide on a Ni/La₂O₃ catalyst containing 10 wt% Ni prepared by the impregnation method was studied. The space-time yield of methane was 3000 g/(kg·h) at conditions of 350 ^oC, GHSV of 30000 h^–1, 1.5 MPa pressure, and H₂/CO₂ molar ratio of 4/1. The selectivity for methane was 100% with different CO₂ conversions. Combined with X-ray diffraction and H₂ temperature-programmed reduction analyses, this suggested that the reaction mechanism on Ni/La₂O₃ may be different from that on Ni/γ-Al₂O₃. The formation of lanthanum oxycarbonate (La₂O₂CO₃) can play an important role in the activation of CO₂.

Key words: carbon dioxide, methanation, nickel, lanthana, supported catalyst, lanthanum oxycarbonate