Synergetic effect of metal–support for enhanced performance of the Cu–ZnO–ZrO2/UGSO catalyst for CO2 hydrogenation to methanol

Abstract

Novel Cu–ZnO–ZrO₂/UGSO catalysts for CO₂ hydrogenation to methanol were developed using a metallurgical residue (UGSO) as the catalytic support, with special focus on understanding the effect of (i) synergy between Cu/Zn/Zr and UGSO composition on the catalytic activity and stability, and (ii) UGSO modification on the structure–activity relationship of the developed catalysts. Zr acts as a structure promoter to enhance Cu dispersion and facilitates CO₂ conversion. The highest methanol yield is achieved for CZ9Zr/UGSO (10 wt% Cu, 7.5 wt% Zn, 9 wt% Zr), attributable to the highest (i) Mg/Cu surface ratio and (ii) interfacial contact Cu–ZrO₂. Further modification of UGSO by H₂O₂ (UGSO-H) increases by 3 times the surface area and endows CZ9Zr/UGSO-H with the best CO₂ conversion and 57% higher methanol yield at 240 °C/20 bar compared to a commercial Cu–ZnO-based catalyst. These findings may pave the way for effective utilization of the no-marketable-value residue as a catalytic support in other CO₂ conversion processes.