文献类型：期刊文献

英文题名：Hydrogenation of cyclohexene over Ru-Zn/Ru(0001) surface alloy: A first principles density functional study

作者：Yuan, Pei-Qing[1];Wang, Bing-Qiang[2];Ma, Yue-Ming[1];He, Hui-Min[1];Cheng, Zhen-Min[1];Yuan, Wei-Kang[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Shanghai Supercomp Ctr, Shanghai 201203, Peoples R China

年份：2009

卷号：301

期号：1-2

起止页码：140

外文期刊名：JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

收录：;EI(收录号：20091011945691);WOS:【SCI-EXPANDED(收录号:WOS:000264614500020)】；

语种：英文

外文关键词：Surface alloy; DFT; Partial hydrogenation; Benzene

摘要：In this work, the hydrogenation of cyclohexene over Ru-Zn/Ru(0 0 0 1) surface alloy was investigated by a DFT study so as to improve the understanding of the catalytic mechanism of the partial hydrogenation of benzene to cyclohexene over Ru-Zn alloy catalyst. Calculation results show that the presence of Zn atoms on the surface alloy results in not only a direct decrease in sites for the chemisorption of cyclohexene but also a depressed adsorption capability of the neighboring surface Ru sites. For an adsorbed cyclohexene molecule, whether the subsequent hydrogenation can be readily performed actually is determined by the relative position among the Zn atom, the H atom, and the adsorbed cyclohexene molecule. In most cases, the hydrogenation is forbidden because of the repulsion from Zn atoms to the nearby H atoms. Only in the specific situations in which the H atom participating in the reaction is not immediately close to the Zn atom, can the hydrogenation be accomplished with a relatively lower activation energy compared with the reactions on the Ru(0 0 0 1) surface. From the perspectives of adsorption and reaction kinetics, Ru-based catalyst modified by metallic Zn is no longer suitable for the hydrogenation of cyclohexene, which is supposed to be crucial to the improvement of cyclohexene yield in the partial hydrogenation of benzene over Ru-Zn alloy catalyst. (C) 2008 Elsevier B.V. All rights reserved.