基于层状锌铝复合氢氧化物前驱体优化制备Cu/ZnO/Al_(2)O_(3)气相醛加氢催化剂  

Preparation of Cu/ZnO/Al_(2)O_(3) catalyst based on ZnAl-layered double hydroxide precursor for gas-phase aldehyde hydrogenation

作　　者：白鹏[1] 刘函澎 陈雪娇[1] 张永辉[1] 赵振祥 吴萍萍[1] 黄德鑫 吴先锋 张志华 BAI Peng;LIU Hanpeng;CHEN Xuejiao;ZHANG Yonghui;ZHAO Zhenxiang;WU Pingping;HUANG Dexin;WU Xianfeng;ZHANG Zhihua(School of Chemistry&Chemical Engineering in China University of Petroleum(East China),Qingdao 266580,China;School of Chemical Engineering in Guangdong University of Petrochemical Technology,Maoming 525000,China)

机构地区：[1]中国石油大学(华东)化学化工学院,山东青岛266580 [2]广东石油化工学院,广东茂名525000

出　　处：《中国石油大学学报（自然科学版）》2024年第4期224-232,共9页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家重点研发计划项目(2022YFA1503400)。

摘　　要：以偏铝酸钠作为铝源通过一步法、两步法和混合法引入Cu制备基于ZnAl-LDH前驱体的3种不同的Cu/ZnO/Al_(2)O_(3)催化剂,对催化剂及其前驱体结构性质进行表征,结合辛烯醛(2-乙基-2-己烯醛,EPA)加氢反应评价结果,探究不同制备方法、不同铝的引入方式对ZnAl_(2)O_(4)尖晶石形成的影响,考察不同条件下所得催化剂的结构与反应性能之间的构效关系。结果表明:与工业催化剂相比,在辛烯醛气相加氢反应中混合法制得的催化剂与工业催化剂活性相当,产物选择性在空速1.5 h^(-1)时高于工业剂1.9%,在空速4.0 h^(-1)时高于工业剂2.5%;以偏铝酸钠作为铝源制备的ZnAl-LDH前驱物大大提高锌铝结合效率,减少非结合Al_(2)O_(3)的产生,提高产物选择性,同时实现380℃低温焙烧条件下ZnAl-LDH向ZnAl_(2)O_(4)尖晶石的转变,避免传统的高温焙烧过程中CuO的烧结。Three different Cu/ZnO/Al_(2)O_(3) catalysts based on ZnAl-LDH precursors were prepared using sodium meta-aluminate as the aluminum source through one-step,two-step,and mixed methods.The structural properties of the catalysts and their precursors were characterized.Combined with the catalytic results for octenal(2-ethyl-2-hexenal,EPA)hydrogenation reaction,the effects of different preparation methods and aluminum introduction methods on the formation of ZnAl_(2)O_(4) spinel were investigated,and the structure-activity relationship between the structure of the obtained catalysts and their catalytic performance under different conditions was studied.Results show that the catalyst obtained by the mixed method exhibites comparable activity to industrial catalysts in the gas-phase hydrogenation of octenal.The product selectivity is 1.9%and 2.5%higher than that of industrial catalyst at a space velocity of 1.5 and 4.0 h^(-1),respectively.This is mainly because the ZnAl-LDH precursor prepared with sodium meta-aluminate as the aluminum source greatly improves the zinc aluminum binding efficiency,reduces the production of unbound Al_(2)O_(3),improves product selectivity,and achieves the transformation of ZnAl-LDH to ZnAl_(2)O_(4) spinel under low calcination temperature(380℃),which avoides the sintering of CuO in traditional high-temperature calcination processes.

关 键 词：Cu/ZnO/Al_(2)O_(3)催化剂 ZnAl_(2)O_(4)尖晶石 ZnAl-LDH 气相醛加氢 

分 类 号：TQ251.11[化学工程—有机化工]