Study On Ga-based Catalysts For Dehydrogenation Of Propane To Propene

As an important chemical raw material,the demand of propene is increasing in recent years.Dehydrogenation of propane(PDH)to propene has become an effective and feasible technical route.In propane dehydrogenation catalytic system,Ga-based catalysts have high dehydrogenation activity,thermal stability and good regeneration performance.In this paper,Ga-based catalysts were successfully prepared by sugar foams template method.The characterizations of catalysts were investigated by XRD,Ar physisorption,SEM,TEM,NH3-TPD,71Ga MAS NMR,XPS,Py-IR.The PDH performance was evaluated under 500℃,3000 h-1 and ambient pressure reaction conditions.Ga2O3 nanoparticle catalysts(SxCF-Ga2O3)were prepared by sugar foams template method.The addition of sucrose could reduce the crystallinity and the average crystallite size of SxCF-Ga2O3(x=4,6,8)catalysts,and increase the BET surface area of catalysts.At the sucrose/Ga2O3 molar ratio of 6,the proportion of tetrahedral Ga3+cation was the largest,and the acid sites of weak-medium strength emerged.The initial catalytic activity was achieved over S6CF-Ga2O3 catalyst with the propane conversion of 46.63%and propene selectivity of 90.38%.GaAl catalysts were prepared by sugar foams template method.With the addition of Al,the crystallinity and the average crystallite size decreased of the GaAl catalysts,and the BET surface area further increased.At the Ga/Al molar ratio of 100:20,the Lewis acid density associated with the tetrahedral Ga3+ cation was enhanced,and the acid sites of weak and weak-medium strength increased.The initial catalytic activity was achieved over 100Ga20Al catalyst with the propane conversion of 52.90%and propene selectivity of 80.32%.GaCe catalysts were prepared by sugar foams template method.With the addition of Ce,the crystallinity and the average crystallite size decreased of the GaCe catalysts.At the Ga/Ce molar ratio of 100:1,the Lewis acid density associated with the tetrahedral Ga3+cation was enhanced,the acid sites of weak strength increased.The initial catalytic activity was achieved over 100Ga1Ce catalyst with the propane conversion of 56.40%and propene selectivity of 80.70%.