Hydrogenation of Carbon Dioxide to Methanol over Non-Cu-based Heterogeneous Catalysts

Abstract

The increasing atmospheric CO₂ level makes CO₂ reduction an urgent challenge facing the world. Catalytic transformation of CO₂ into chemicals and fuels utilizing renewable energy is one of the promising approaches toward alleviating CO₂ emissions. In particular, the selective hydrogenation of CO₂ to methanol utilizing renewable hydrogen potentially enables large scale transformation of CO₂ . The Cu-based catalysts have been extensively investigated in CO₂ hydrogenation. However, it is not only limited by long-term instability but also displays unsatisfactory catalytic performance. The supported metal-based catalysts (Pd, Pt, Au, and Ag) can achieve high methanol selectivity at low temperatures. The mixed oxide catalysts represented by M_a ZrO_x (M_a =Zn, Ga, and Cd) solid solution catalysts present high methanol selectivity and catalytic activity as well as excellent stability. This Review focuses on the recent advances in developing Non-Cu-based heterogeneous catalysts and current understandings of catalyst design and catalytic performance. First, the thermodynamics of CO₂ hydrogenation to methanol is discussed. Then, the progress in supported metal-based catalysts, bimetallic alloys or intermetallic compounds catalysts, and mixed oxide catalysts is discussed. Finally, a summary and a perspective are presented.

Keywords: Carbon Dioxide; Heterogeneous Catalysts; Hydrogenation; Methanol; Non−Cu based catalysts.