Pt-Sn clusters anchored at Al_(penta)^(3+) sites as a sinter-resistant and regenerable catalyst for propane dehydrogenation  

作　　者：Xinyue Zhu Tinghai Wang Zhikang Xu Yuanyuan Yue Minggui Lin Haibo Zhu 

机构地区：[1]National Engineering Research Center of Chemical Fertilizer Catalyst,School of Chemical Engineering,Fuzhou University,Fuzhou 350002,Fujian,China [2]State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,Shanxi,China

出　　处：《Journal of Energy Chemistry》2022年第2期293-301,共9页能源化学（英文版）

基　　金：Financial supports of the National Natural Science Foundation of China(21878050,91934301);the State Key Laboratory of Coal Conversion(J21-22-620);the 111 Project(D17005)。

摘　　要：Pt-based catalysts are widely used in propane dehydrogenation reaction for the production of propylene.Suppressing irreversible deactivation caused by the sintering of Pt particles under harsh conditions and regeneration process is a significant challenge in this catalyst.Herein,a series of highly ordered mesoporous Al_(2)O_(3) supports with different levels of Al3+penta sites,are fabricated and used as the support to disperse Pt-Sn_(2) clusters.Characterizations of Pt-Sn_(2)/meso-Al_(2)O_(3) with XRD,NMR,CO-IR,STEM,TG,and Raman techniques along with propane dehydrogenation-regeneration cycles test reveal the structure-stability-re generability relationship.The coordinatively unsaturated pentacoordinate Al_(Al3+penta)^(3+)can strongly anchor Pt atoms via a formation of Al-O-Pt bond,and thus stabilize the Pt-based particles at the surface of Al_(2)O_(3).The stability and regenerability of Pt-Sn2/meso-Al_(2)O_(3) are strongly dependent on the content of Al3+penta sites in the Al_(2)O_(3) structure,and a high level of Al3+penta sites can effectively prevent the agglomeration of Pt-Sn2 clusters into large Pt nanoparticles in the consecutive dehydrogenation-regeneration cycles.The Pt-Sn2/meso-Al_(2)O_(3)-600 with the highest level of Al_(penta)^(3+) (50.8%)delivers the best performance in propane dehydrogenation,which exhibits propane conversion of 40%and propylene selectivity above 98%at 570℃ with 10 vol%C_(3)H_(8) and 10 vol% H_(2) feed.A slow deactivation in this catalyst is ascribed to the formation of coke,and the catalytic performance can be fully restored in the consecutive dehydrogenation-regeneration cycles via a simple calcination treatment.

关 键 词：Propane dehydrogenation Pt catalyst REGENERATION Sinter-resistance 

分 类 号：TQ221.212[化学工程—有机化工] TQ426