采用盐酸酸化的蒙脱土负载共沉淀法制备的CuO—ZnO—Al2O3,制备了CuO-ZnO-Al2O3蒙脱土催化剂,用BET、FT—IR和XRD对催化剂结构进行了表征,并在固定床微型反应器中研究了其对二氧化碳加氢制备二甲醚的催化活性.在反应混合气空速为1600h-1,蒙脱土:CuO-ZnO-Al2O3=3:7(质量比)的条件下,测定了酸化浓度、反应温度、压力和H2/CO2体积比对催化活性的影响。结果表明,用1mol/LHCl酸化蒙脱土,反应温度为545K,反应压力为3MPa,H2/CO2体积比为3时,CO2的单程转化率达到26.5%,二甲醚的选择性和收率分别为16.7%和414%.甲醇和二甲醚的总收率达到15.7%。
Catalyst of CuO-ZnO-Al2O3/montmorillonite was prepared by supporting CuO-ZnO-Al2O3 with acidified montmorillonite. The catalyst structure was characterized by the methods of BET, FT-IR and XRD. Catalytic activity of CuO-ZnO-Al2O3/montmorillonite for the synthesis of dimethyl ether by hydrogenation of CO2 was studied in the fixed-bed reactor. The effects of acidity of HCl, the reaction temperature, pressure and volume ratio of HE/CO2 were investigated at mixed gases feed speed of 1 600 h-1 and mass ratio of montmorillonite : CuO-ZnO-Al2O3=3:7.With lmol/L HC1 acidified montmorillonite, under the conditions of pressure at 3 MPa, temperature at 545 K and H2/CO2 is 3/1 (volume ratio), the conversion of CO2 is 26.5%, the total yield of dimethyl ether and methanol is 15.7%, the selectivity and yield of dimethyl ether can be reached to 16.7% and 4.4%, respectively.