Synthesis And Formation Mechanism Of ZSM-5 Zeolite By TMS-GC Method

Due to many unique characters in the chemical composition, crystal structure and physical and chemical properties, ZSM-5 zeolites were widely used in catalytic materials and adsorption materials. In this paper, XRD, SEM, FT-IR and TMS-GC method were used to examine the synthesis and technical conditions of ZSM-5 zeolite, in combination with the analysis result of 29Si MAS NMR, and the synthesis mechanism were introduced. The specific topics of this thesis are as follows:ZSM-5 zeolite was successfully synthesized by different synthesis methods, and was characterized by XRD, SEM, FT-IR, and TMS-GC method. Then two-steps crystallization method as the best synthesis method was drawn.A detailed study of the effects of alkalinity, ratio of silica and alumina, the amount of water and template on the crystallization reaction were studied, and the products were characterized by many analyzed techniques. The optimum synthesis conditions were determined by experiments. That is:n(SiO2)/n(Al2O3)=90.9, n(Si02)/n(Na20)=28.6, n(SiO2)/n(BuNH2)=2.27, n(SiO2)/n(H2O)=0.23, crystallization time is firstly 9 h at the temperature of 180℃, and then 36 h at the temperature of 160℃.On the optimal synthesis conditions, there is Lentz method analyzing liquid of ZSM-5 zeolites. After that, the liquors of ZSM-5 zeolites in different crystallization time were silanized, and then was analyzed by GC-MS. The results show that the content of oligomers change in the synthesis process of ZSM-5 zeolite, then proposes the synthesis mechanism of ZSM-5 zeolite.