Cu-ZnO-ZrO_(2)催化剂孔结构调控CO_(2)加氢制甲醇性能研究  

Pore structure modulation of Cu-ZnO-ZrO_(2) catalysts for methanol production from CO_(2) hydrogenation

作　　者：李忠林 王禹皓[2,3] 郑燕娥 江磊[2,3] 李志强 王春良[2,3] 何伦[2,3] 李孔斋 LI Zhonglin;WANG Yuhao;ZHENG Yane;JIANG Lei;LI Zhiqiang;WANG Chunliang;HE Lun;LI Kongzhai(Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming 650093,China;State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China;Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]昆明理工大学化学工程学院,云南昆明650093 [2]昆明理工大学复杂有色金属资源清洁利用国家重点实验室,云南昆明650093 [3]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《燃料化学学报（中英文）》2024年第9期1235-1248,共14页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(22368032,22268026,22169014);云南省自然科学基金(202201BE070001-001,202302AG050005,202301AT070448,202301AT070438,202301AU070096)资助。

摘　　要：采用胶质晶体模板法制备了不同孔径Cu-ZnO-ZrO_(2)(CZZ)催化剂,并对其CO_(2)加氢制甲醇性能进行了研究。结果表明,通过改变催化剂孔径可以实现ZnO粒径大小的调控,较小的粒径表现出更卓越的催化性能。其中,在孔径为55 nm的(CZZ-55)样品上,ZnO粒径为14.5 nm,CO_(2)转化率为14.83%,甲醇选择性为78.8%,甲醇产率可达345.8 g/(kg·h)。原位漫反射傅里叶变换红外光谱结果表明,在CZZ催化剂上CO_(2)加氢制甲醇遵循甲酸盐路径,ZnO-ZrO_(2)界面是CO_(2)吸附和活化的活性位点,而三维有序大孔结构有助于形成更分散的ZnO-ZrO_(2)活性位,提高了CO_(2)转化率。并且孔径大小对中间体的转化具有一定影响,孔径越小,甲酸盐更容易转化为甲醇。此外,三维有序的大孔结构为产物(水汽和甲醇)快速扩散提供了“高速通道”,有效抑制CO_(2)加氢的副产物水汽对活性位的毒化作用,较大程度提高了催化剂的稳定性,在600 h内无明显失活。Copper-based catalysts have attracted much attention for the hydrogenation of carbon dioxide(CO_(2))to synthesize methanol,however,problems including low methanol selectivity,easy sintering of the active components of the catalysts,and poor stability are commonly encountered.In this study,Cu-ZnO-ZrO_(2)(CZZ)catalysts with macroporous and nonporous morphology were prepared by the colloidal crystal template method and the conventional co-precipitation method,respectively,and their CO_(2) hydrotreating to methanol performance was investigated.In the colloidal crystal template method,polymethyl methacrylate(PMMA)was chosen as the template structure,and the diameter size of the macropores was regulated by controlling the PMMA particle size,so that samples with different pore sizes were prepared.The results show that compared with the bulk samples prepared by the co-precipitation method,the samples prepared by the template method have a permeable macroporous structure,and due to the special three-dimensional ordered structure of the macroporous holes,the ZnO can be uniformly dispersed around the pore wall formed by Cu,which effectively prevents the growth of ZnO particles.Moreover,by changing the pore size of the macropores,the regulation of ZnO particle size can be realized,and smaller ZnO particle size shows more excellent catalytic performance.Among them,excellent catalytic performance and application potential were demonstrated on a(CZZ-55)sample with a pore size of 55 nm,a ZnO particle size of 14.5 nm,a CO_(2) conversion of 14.83%,a methanol selectivity of 78.8%,and a methanol yield up to 345.8 g/(kg·h)which is 1.52 times higher than the performance of the nonporous catalyst.The results of in situ diffuse reflectance infrared Fourier transform spectroscopy showed that the methanol synthesis from CO_(2) hydrogenation over the CZZ catalyst followed the formate pathway,and the ZnO-ZrO2 interface was the active site for CO_(2) adsorption and activation.Moreover,the three-dimensional ordered macroporous structure prov

关 键 词：CO_(2)加氢制甲醇 孔径调控 ZnO粒径 甲酸盐 稳定性 

分 类 号：O643[理学—物理化学]