Si掺杂对Cu/ZrO_(2)催化CO_(2)加氢制甲醇性能的影响  

Effect of Si-doped Cu/ZrO_(2) on the performance of catalysts for CO_(2) hydrogenation to methanol

作　　者：戴文华 辛忠 DAI Wenhua;XIN Zhong(Shanghai Key Laboratory of Multiphase Materials Chemical Engineering,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China;State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学化工学院,上海市多相结构材料化学工程重点实验室,上海200237 [2]华东理工大学化学工程联合国家重点实验室,上海200237

出　　处：《化工学报》2022年第8期3586-3596,共11页CIESC Journal

基　　金：国家自然科学基金项目(21808062,21808064,21776091);中央高校基本科研业务费专项资金项目(22A1817025)。

摘　　要：为了提高Cu/ZrO_(2)催化剂在二氧化碳加氢制甲醇中的催化活性,制备了一系列不同Si/Zr的Si-ZrO_(2)载体并负载5%(质量分数)Cu得到了Cu/Si-ZrO_(2)催化剂。对所制备的催化剂进行了X射线衍射(XRD)、N_(2)物理吸脱附(BET)、X射线光电子能谱(XPS)、氢气程序升温还原(H_(2)-TPR)、二氧化碳程序升温脱附(CO_(2)-TPD)及高分辨透射电子显微镜(HRTEM)的表征。结果表明,Si的掺杂使得Cu/ZrO_(2)体系获得了稳定的晶相,大的比表面积和更多的碱性位点,尤其是中强碱性位点,同时产生了更多的氧空位,促进了CO_(2)的吸附和转化,因此得到了更高活性的催化剂。当Si与Zr的摩尔比为0.2时,在质量空速为6000 ml·g^(-1)·h^(-1),温度为220℃、压力为3.0 MPa,V(H_(2))∶V(CO_(2))=3∶1(体积比)条件下,催化剂的CO_(2)转化率为4.6%,CH_(3)OH选择性为85%。In order to improve the catalytic activity of Cu/ZrO_(2) catalysts in carbon dioxide hydrogenation to methanol, a series of Si-ZrO_(2) supports with different Si/Zr were prepared and loaded 5% Cu to obtain the Cu/Si ZrO_(2) catalysts. The prepared catalysts were characterized by X-ray diffraction (XRD), N_(2) physisorption measurements (BET), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H_(2)- TPR), temperature-programmed desorption of CO_(2)(CO_(2)-TPD) and high-resolution transmission electron microscopy (HRTEM). The results showed that the doping of Si promoted Cu/ZrO_(2) system to obtain stable crystal phase, abundant specific surface area and more basic sites, especially medium and strong basic sites. At the same time, higher oxygen vacancy concentration was generated, which promoted the adsorption and activation of CO_(2), and thus the catalyst with Si/Zr molar ratio 0.2 which possessed higher activity with 4.6% CO_(2) conversion and 85% CH_(3)OH selectivity was obtained at 220℃ under 3.0 MPa with WHSV=6000 ml·g^(-1)·h^(-1), H_(2)/CO_(2) volume ratio 3/1.

关 键 词：活化 二氧化碳 催化剂 甲醇合成 二氧化硅 改性二氧化锆 

分 类 号：TQ546.4[化学工程—煤化学工程]