A highly selective and stable ZnO-ZrO ₂ solid solution catalyst for CO ₂ hydrogenation to methanol

Abstract

Reduction of CO ₂ to methanol using renewable hydrogen is a promising but challenging strategy for carbon capture and utilization.

Abstract

Although methanol synthesis via CO hydrogenation has been industrialized, CO ₂ hydrogenation to methanol still confronts great obstacles of low methanol selectivity and poor stability, particularly for supported metal catalysts under industrial conditions. We report a binary metal oxide, ZnO-ZrO ₂ solid solution catalyst, which can achieve methanol selectivity of up to 86 to 91% with CO ₂ single-pass conversion of more than 10% under reaction conditions of 5.0 MPa, 24,000 ml/(g hour), H ₂/CO ₂ = 3:1 to 4:1, 320° to 315°C. Experimental and theoretical results indicate that the synergetic effect between Zn and Zr sites results in the excellent performance. The ZnO-ZrO ₂ solid solution catalyst shows high stability for at least 500 hours on stream and is also resistant to sintering at higher temperatures. Moreover, no deactivation is observed in the presence of 50 ppm SO ₂ or H ₂S in the reaction stream.