Methanol and DME Co-production from CO2 hydrogenation over hybrid catalysts

Catalytic hydrogenation of CO2 into methanol and dimethyl ether was carried out over hybrid catalysts consisting of methanol-synthesis catalyst and zeolite. The methanol-synthesis catalyst, Cu/ZnO/Al2O3, was prepared by a co-precipitation method. Then it was physically mixed with HZSM-5 zeolite at weight ratios of 2:1, 1:1 and 1:2. The CO2 hydrogenation reaction was conducted in a fixed-bed microreactor at 250℃ and 40 bar in pre-mixed H2/CO2 feed with H2: CO2 molar ratios of 3:1 and 7:1. Products detected include methanol, dimethyl ether, carbon monoxide and water. Conversion of CO2 and yield of oxygenated products were influenced by the weight ratio of Cu/ZnO/Al2O3: HZSM-5 in the hybrid system and also the feed ratio. The Cu/ZnO/Al2O3: HZSM-5 hybrid at 1:1 resulted in methanol yield of 22.0% and was found to be an efficient hybrid catalyst for the CO2 hydrogenation reaction