Molecular sieves of SAPO-41 with different silicon contents were synthesized and characterized by XRD,N2 adsorption,XRF,pyridine-IR and 29SiMAS-NMR.The isomerization properties of the SAPO-41 were investigated by usin...Molecular sieves of SAPO-41 with different silicon contents were synthesized and characterized by XRD,N2 adsorption,XRF,pyridine-IR and 29SiMAS-NMR.The isomerization properties of the SAPO-41 were investigated by using m-xylene as a feedstock.The SAPO-41 obtained from the synthesis gel with SiO2/Al2O3=0.3 showed the highest activity to the isomerization of m-xylene and the largest number of Brnsted acid sites was also observed with Py-IR over this sample.The state of Si in the framework of SAPO-41 plays a predominant role on the Brnsted acidity.The relationship between the activity and the acidity obtained in this study can be explained in terms of the distribution of stronger Brnsted acid sites.展开更多
文摘Molecular sieves of SAPO-41 with different silicon contents were synthesized and characterized by XRD,N2 adsorption,XRF,pyridine-IR and 29SiMAS-NMR.The isomerization properties of the SAPO-41 were investigated by using m-xylene as a feedstock.The SAPO-41 obtained from the synthesis gel with SiO2/Al2O3=0.3 showed the highest activity to the isomerization of m-xylene and the largest number of Brnsted acid sites was also observed with Py-IR over this sample.The state of Si in the framework of SAPO-41 plays a predominant role on the Brnsted acidity.The relationship between the activity and the acidity obtained in this study can be explained in terms of the distribution of stronger Brnsted acid sites.