文献类型：期刊文献

英文题名：Effect of Zn on the selectivity of Ru in benzene partial hydrogenation from density functional theory investigations

作者：Xia, Yi[1,2];Fan, Chen[1];Zhou, Zi-Lan[1,2];Zhu, Yi-An[1];Zhou, Xing-Gui[1]

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

年份：2013

卷号：370

起止页码：44

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

收录：;EI(收录号：20131316140880);WOS:【SCI-EXPANDED(收录号:WOS:000316094300007)】；

基金：This work is supported by Natural Science Foundation of China (No. 21003046), 973 project of Ministry of Science and Technology of China (No. 2012CB720500), and Fundamental Research Funds for Central Universities (No. WA1014027). The computational time provided by the Notur project is highly acknowledged.

语种：英文

外文关键词：DFT; Partial hydrogenation; Cyclohexene; Ru(0001); Zn

摘要：Catalytic hydrogenation of benzene to cyclohexene is of great importance in the petroleum industry. The introduction of Zn into Ru catalyst can significantly improve the selectivity toward cyclohexene. To elucidate the effect of Zn on the enhanced selectivity, the adsorption of all the possible reaction intermediates involved is investigated by performing density functional theory calculations, and the transition states for the hydrogenation steps are identified by using the constrained Broyden minimization method. With the introduction of Zn into Ru(0 0 0 1) at high H surface coverage, the adsorption energies of the intermediates are much lower than those on bare Ru(0 0 0 1), which indicates that the desorption of cyclohexene is promoted on the alloyed surface. The calculated energy barriers for the hydrogenation steps from benzene to cyclohexene are in the region of 0.58-1.04 eV, and the hydrogenation of benzene on Zn/Ru(0 0 0 1) follows the Horiuti-Polanyi mechanism with the successive hydrogenation of the neighboring C atoms in the hexagonal carbon ring. The deep hydrogenation of cyclohexene to produce cyclohexane is kinetically hindered with the introduction of Zn, which also gives rise to the improvement of the selectivity toward cyclohexene. (c) 2012 Elsevier B.V. All rights reserved.