ZSM-5高硅分子筛硅烷化疏水改性的研究

Study on hydrophobic silylation modification of high silica molecular sieve ZSM-5

以甲苯为溶剂,正辛基三乙氧基硅烷(OTS)为改性剂,进行了ZSM-5高硅分子筛疏水改性研究。通过傅立叶红外(FT-IR)、X射线粉末衍射(XRD)、N2吸附-解吸附、静态水接触角、水与正己烷的静态吸附,以及水热稳定性试验等测试了改性前后样品结构与性能。结果表明,通过硅烷化改性在ZSM-5上接枝了-Si(CH2)7CH3基团,并实现了超疏水性。当0.8g ZSM-5使用0.24g改性剂时,改性后分子筛的接触角达152°,水吸附量下降了1.49%,比表面积、孔容、孔径分别减小了62.7m2/g、0.0329cm3/g、0.42nm,孔道长程有序性有所降低,且具有较高的水热稳定性。

Hydrophobic modification of high silica molecular sieve ZSM-5 was studied, which is modified by triethoxyoctylsilane （OTS） in toluene. The structure and properties of samples were characterized by FI＇-IR, XRD, N2 adsorption-desorption,water static contact angle, static adsorption experiment of water and n-hexane, and hydrothermal stability experiment test before and after modifi- cation. Experimental results show that-Si（ CH2）7CH3 groups grafted on ZSM-5 could effectively improve the hydrophobicity of mo- lecular sieve. When 0. 24g of modifying agent is applied to modify 0. 8g of ZSM-5 ,the modified sieve shows a superhydrophobicity with a contact angle up to 152°. After hydrophobic modification, the water adsorption capacity, specific surface area, pore volume, and pore diameter of ZSM-5 fell by 1.49%, 62.7 m^2/g,0. 0329 cm^3/g, and 0.42 nm respectively, the long-term ordering of pore channel decreased slightly,and the hydrothermal stability was enhanced.