Role of Y_(2)O_(3)in Cu/ZnO/Y_(2)O_(3)catalysts for CO_(2)hydrogenation to methanol  

CO_(2)加氢制甲醇Cu/ZnO/Y_2O_3催化剂中Y_(2)O_(3)的作用

作　　者：Ziguo Cai Xuefeng Yu Penglong Wang Huifang Wu Ruifeng Chong Limin Ren Tao Hu Xiang Wang 蔡子国;于学峰;王鹏龙;吴慧芳;种瑞峰;任利敏;胡涛;王翔(大连理工大学化工学院,精细化工国家重点实验室,辽宁大连116024;河南大学化学与分子科学学院,河南开封475004;大连理工大学化学学院,辽宁大连116024)

机构地区：[1]State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China [2]College of Chemistry and Molecular Sciences,Henan University,Kaifeng 475004,Henan,China [3]School of Chemistry,Dalian University of Technology,Dalian 116024,Liaoning,China

出　　处：《Chinese Journal of Catalysis》2025年第3期410-419,共10页催化学报(英文)

基　　金：国家自然科学基金(22272016);中央高校基本科研业务费(DUT21RC(3)113).

摘　　要：CuZn-based catalyst is an attractive catalyst for methanol synthesis from CO_(2)hydrogenation,but it early deactivates and its methanol yield still needs to improve.In this study,Y_(2)O_(3)was introduced to Cu/ZnO using a one-pot hydrothermal method,and exhibits a synergistic effect of ZnO and Y_(2)O_(3)on enhancing methanol yield and the stability.We found that the interaction between Y_(2)O_(3)and ZnO results in abundant oxygen vacancies formation,thereby enhancing CO_(2)adsorption and activation.Kinetic analysis and in situ DRIFTS suggest that RWGS forming CO and methanol formation compete for a mutual intermediate HCOO^(*),and the introduction of Y_(2)O_(3)to Cu/ZnO raises the energy barrier for the CO formation but lowers that for methanol formation,thus enhancing the methanol yield on Cu/ZnO/Y_(2)O_(3).CO_(2)加氢制甲醇是碳的捕集、利用和封存中最具吸引力的策略之一.甲醇不仅可用作燃料,而且还是生产其他高附价值化学品(包括低碳烯烃、汽油、芳烃等)的基本原料.CuZn基催化剂因其成本低、活性高而受到广泛关注.然而,Cu和ZnO颗粒在副产物水的作用下会发生烧结团聚,从而导致甲醇选择性降低.Y_(2)O_(3)的引入中可提高催化剂的甲醇产率,但其作用机理仍不清楚.本文通过一锅水热法制备了Cu/ZnO,Cu/ZnO/Y_(2)O_(3)和Cu/Y_(2)O_(3)催化剂,旨在阐明Y_(2)O_(3)在Cu/ZnO/Y_(2)O_(3)催化剂中的作用.催化剂性能评价结果表明,相比于Cu/ZnO和Cu/Y_(2)O_(3)催化剂,Cu/ZnO/Y_(2)O_(3)催化剂表现出最高的甲醇产率,这可能归因于ZnO和Y_(2)O_(3)载体之间的协同效应.比表面积测试结果表明,在Cu/ZnO中引入Y_(2)O_(3)后,催化剂的比表面积随着Y_(2)O_(3)引入量的增加而逐渐增大.然而,甲醇产率呈现出先增加后减少的趋势.其中,甲醇产率最高的Cu/ZnO/Y_(2)O_(3)催化剂的比表面积在所有催化剂中处于中等水平,这说明比表面积并不是导致催化剂活性增加的主要原因.X射线衍射和H_(2-)程序升温还原结果表明,Y_(2)O_(3)的引入可以提高催化剂表面Cu物种的分散度以及增强其与载体之间的相互作用.拉曼光谱、X射线光电子能谱和CO_(2)程序升温脱附结果表明,Y_(2)O_(3)的引入使催化剂表面产生了更多的氧空位,从而增加了对CO_(2)物种的吸附和活化.动力学分析和原位漫反射红外光谱结果表明,HCOO^(*)中间物种为产物CO和甲醇的共同中间物种,两者存在竞争.在Cu/ZnO/Y_(2)O_(3)催化剂中,Y_(2)O_(3)的引入可以增大生成CO的能垒,同时减小生成甲醇的能垒,从而提高了催化剂上的甲醇产率.综上所述,本文发现Y_(2)O_(3)与ZnO之间的协同效应提高了甲醇的产率,并阐明了Y_(2)O_(3)在催化剂中的作用及反应机理,为高效催化剂的设计和对助剂的理解提�

关 键 词：Methanol yield Oxygen vacancies Kinetics Fourier transformed infrared Intermediate 

分 类 号：O643.36[理学—物理化学]