Catalytic performance of calcium oxide-modified copper- Zinc-alumina catalysts in methanol synthesis from CO2 hydrogenation

Proposed as a carbon utilization method, the catalytic hydrogenation with carbon dioxide (CO₂) as feedstock to produce methanol is a viable approach for utilizing excess CO₂ and countering climate change. The current work aims to enhance methanol production from CO₂ hydrogenation over a CaO-promoted Cu/ZnO-based catalyst supported on Al2O3. The catalysts, prepared via impregnation method with 10 wt.% active metal loading and 1.0 wt% CaO promoter, were analyzed for physicochemical properties using N2 physical adsorption-desorption and XRD. It was found that the addition of a CaO promoter improved the textural properties of the catalyst, where a larger BET surface area (214.9 m²/g) and smaller crystallite size (7.76 nm) were obtained. The 1.0 wt% CaO-promoted catalyst showed the highest CO₂ conversion (19.14%) and methanol yield (4.66%) due to its excellent textural properties and enhanced basicity.