文献类型：会议论文

英文题名：Improved selectivity and coke resistance of core-shell alloy catalysts for propane dehydrogenation from first principles and microkinetic analysis

作者：Xiao, Ling[1];Ma, Fang[1];Zhu, Yi-An[1];Sui, Zhi-Jun[1];Zhou, Jing-Hong[1];Zhou, Xing-Gui[1];Chen, De[2];Yuan, Wei-Kang[1]

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

会议论文集：25th International Symposium on Chemical Reaction Engineering (ISCRE)

会议日期：MAY 20-23, 2018

会议地点：Florence, ITALY

语种：英文

外文关键词：Propane dehydrogenation; Core-shell alloy; DFT; Microkinetic modeling

摘要：Microkinetic analysis combined with the results obtained from density functional theory calculations has been performed to examine the catalytic activity and selectivity of Pt-based core-shell alloy catalysts for propane dehydrogenation. Calculated results indicate that substitution of 11 late transition metals for the core region of Pt nanoparticles would significantly modify the electronic structure of the surface Pt atoms through the strain effect and charge transfer. The core-shell catalysts are found to have less negative propylene adsorption energies and higher activation energies for the dehydrogenation reactions than Pt, thus giving rise to a lower catalytic activity and a higher selectivity toward propylene. Linear chemisorption energy and transition state energy scaling relations hold very well in the present work, and the adsorption energy of propylene is identified to be a good descriptor to represent the overall kinetics. The scaling relations also suggest that a higher catalyst selectivity toward propylene can only be achieved at the expense of a lower catalytic activity for propane dehydrogenation. If a compromise is made between catalytic activity and catalyst selectivity, Co@Pt is proposed to be the best core-shell catalyst for propane dehydrogenation.