介孔CuO-ZnO/SiO_2催化剂用于二氧化碳加氢合成甲醇的研究

Study on Mesoporous CuO-ZnO/SiO_2 Catalyst for Hydrogenation of CO_2 to Methanol

采用原位溶胶-凝胶法制备了介孔CuO-ZnO/SiO_2催化剂,考察了表面活性剂类型和焙烧温度对催化剂结构和催化性能的影响。以二氧化碳加氢合成甲醇为探针反应,并结合TG-DTG、BET表征手段对催化剂结构和性能进行了分析。结果表明,采用CTAB为表面活性剂并经450℃焙烧所得的介孔CuO-ZnO/SiO_2催化剂具有高的比表面积和最佳的催化性能;反应条件250℃、3.0 MPa时,该催化剂的CO_2转化率、甲醇选择性分别为21.6%和35.6%。

In the study, a series of mesoporous CuO-ZnO/Si O_2 catalysts were prepared by in-situ sol-gel method. The influence of different surfactants and calcination temperatures were investigated. The catalysts were characterized by a variety of techniques, including themogravimetry analytical technology and N2adsorption-desorption. The catalytic activity of the prepared catalysts was evaluated by the hydrogenation of CO_2 to methanol. In comparation with others, the catalyst prepared with CTAB and calcinated at 450 ℃ possessed higher BET surface area and pore diameter, which was related to the highest activity of it during CO_2 hydrogenation. Less than 250 ℃ and 3.0 MPa, CO_2 conversion and selectivity to methanol of this catalyst were 21.6 % and 35.6 %, respectively.