The Effect Of Promoter B On The Performance Of Pt-based Catalyst For Propane Dehydrogenation

Pt catalyst is widely adopted in commercial propane dehydrogenation processes.However,this kind of catalyst still suffers from the coking problem,which decreases the economics of the process.In this work,alumina and hierarchical Mg-Al spinel were used as the carrier to prepare the supported PtB-x(x=1,2,4)and PtBSn-y(y=1,2,4)catalysts and their catalytic performance for propane dehydrogenation were tested.The catalysts were characterized by CO-Chem,HAADF-STEM,XPS and C3H6-TPD and the geometric and electronic effects of the promoter B on the performance of Pt-based catalysts were discussed.The effect of the addition of B on the coke properties was also explored,based on TG,Raman and elemental analysis results.On both alumina and spinel support,the addition of B can significantly reduce the particle size of Pt and reduce its binding energy and weaken the adsorption of propylene.Therefore,the activity and selectivity of Pt catalyst could be increased.With reaction temperature of 5750C,pressure of 0.1 MPa,a total flow rate of 76 mL/min,and a volume flow ratio of hydrogen to propane of 0.8,0.1 g catalysts,the propane conversion of PtBSn/Al2O3 arrived 23%,selectivity to propylene arrived 99%and PtBSn/MgAl2O4 had superior stability.The results of this work are of great significance for the development and design of a new type of propane dehydrogenation catalyst.