Synergistic effect between Sn and K promoters on supported platinum catalyst for isobutane dehydrogenation  

作　　者：Yiwei Zhang Yuming Zhou Lihui Wan Mengwei Xue Yongzheng Duan Xuan Liu 

机构地区：[1]School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, Jiangsu, China [2]Biochemical and Environmental Engineering College, Nanjing Xiaozhuang University, Nanjing 211171, Jiangsu, China

出　　处：《Journal of Natural Gas Chemistry》2011年第6期639-646,共8页天然气化学杂志（英文版）

基　　金：supported by the National Natural Science Foundation of China (21106017 and 50873026);Specialized Research Fund for the Doctoral Program of Higher Education of China (20100092120047);Production and Research Prospective Joint Research Project of Jiangsu Province of China (Grant No.BY2009153)

摘　　要：Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate （12.4%） and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction.Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate （12.4%） and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction.

关 键 词：synergistic effect Pt-Sn isobutane dehydrogenation 

分 类 号：O643.36[理学—物理化学] TQ243.12[理学—化学]