二氧化碳加氢合成二甲醚CuO-ZnO-SiO_2/HZSM-5型催化剂的研究

CuO-ZnO-SiO_2/HZSM-5 Cataly for Dimethyl Ether Synthesis by Hydrogenation of Carbon Dioxide

采用改进的溶胶-凝胶法制备了一系列CuO-ZnO-SiO2/HZSM-5双功能催化剂,用于CO2加氢一步法合成DME的研究,采用实验室固定床反应活性评价等研究方法,考察了SiO2含量、脱水组分含量以及反应条件对催化剂性能的影响。研究结果表明,添加适量的SiO2能很好的促进CuO和ZnO的分散,SiO2含量在3.5%时效果比较好;HZSM-5沸石分子筛在整个过程中起到了脱水作用,当其含量为10%时所得的双功能催化剂催化活性较好;适宜的反应条件为:反应温度240℃,压力3.0MPa,空速1500～3500h-1,H2/CO2比4∶1。

A series of CuO-ZnO-SiO2/HZSM-5 bifunctional catalysts were prepared using the improved sol-gel methord to study on the hydrogenation of CO2 to DME on one-step. Then some methods, such as the laboratory fixed-bed reaction activity assessment methods, were adopted to discuss the influence of the contents of SiO2 and dehydration components and reaction conditions on the properties of the catalysts. The results indicate that adding the right amount of SiO2 can promote the despersation of CuO and ZnO. The effect is better with the mass of SiO2 3.5%. HZSM-5 plays a role of dehydration and makes gain the better activity of the catalyst when its proportion reachs 10%. The appropriate conditions：the temperature is 240 ℃ ,the pressure is 4.0 MPa,the airspeed is 1 500- 3 500 h ^-1 and H2/CO2 is 4 ： 1.