文献类型：期刊文献

英文题名：On the catalytic behaviors of Cu/SiO2 and Cu/γ-Al2O3 for dimethyl oxalate hydrogenation from microkinetic analysis including a plug flow reactor model

作者：Xiao, Han-Jie[1];Zheng, Hui-Han[1];Lei, Ming[1];Zhou, Jing-Hong[1];Chen, De[2];Zhou, Xing-Gui[1];Zhu, Yi-An[1]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Green Chem Engn & Ind Catalysis, UNILAB, Shanghai 200237, Peoples R China;[2]Norwegian Univ Sci & Technol, Dept Chem Engn, N-7491 Trondheim, Norway

年份：2024

卷号：440

外文期刊名：JOURNAL OF CATALYSIS

收录：;EI(收录号：20244517329530);WOS:【SCI-EXPANDED(收录号:WOS:001354595800001)】；

基金：This work is supported by the National Science Foundation of China (Nos. 22073027 and 91645122) .

语种：英文

外文关键词：Dimethyl oxalate hydrogenation; Cu catalyst; Cluster catalysis; Metal-support interaction; DFT

摘要：Cu-based catalysts have been widely used in dimethyl oxalate (DMO) hydrogenation due to their ability to activate C-O/C=O bonds without breaking C-C bonds. In this work, the electronic structures of Cu/SiO2 and Cu/ gamma-Al2O3 as well as their catalytic performance have been studied by the machine-learning-based stochastic surface walking-global neural network potential (SSW-NN) method, density functional theory calculation, and microkinetic analysis including a plug flow reactor (PFR) model. Among SiO2- and gamma-Al2O3-supported Cun (n = 1-9), the Cu5 and Cu7 clusters are held most tightly on SiO2(111) and gamma-Al2O3(110), respectively. The electron transfer from Cu5 to SiO2(111) leads to the formation of Cu delta+ and Cu0, which are responsible for the stabilization of unsaturated C and O atoms in the intermediates, respectively, while on gamma-Al2O3(110) an electron-rich Cu0-Al3c site is most active. Both the Cu delta+-Cu0 and the Cu0-Al3c sites synergistically catalyze the dissociation of gas-phase species and hydrogenation of intermediates. Under the typical operating conditions, although the selectivity towards methyl glycolate (MG) is invariably highest at the reactor inlet, Cu5/SiO2(111) and Cu7/gamma-Al2O3(110) are actually selective for the production of ethylene glycol (EG) and ethanol (EtOH), respectively, if the overall selectivity is taken into consideration, signifying the importance of including a reactor model to probe the kinetics of series of consecutive reactions. The dissociation of DMO is found to be the rate-determining step, and the high energy barrier for EG dissociation on Cu5/SiO2(111) hinders its deep hydrogenation while the relatively low barrier on Cu7/gamma-Al2O3(110) is beneficial to the formation of EtOH.