纯硅分子筛的合成及其硅烷化改性研究

Study on the synthesis and silanization modification of pure-silica molecular sieve

通过水热法合成了纯硅分子筛S-1,以及采用正辛基三乙氧基硅烷(OTS)为改性剂进行了S-1分子筛疏水改性研究,并采用FT-IR、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。改性产物的比表面积、孔容、孔径分别为334.2m2/g、0.3443cm3/g、3.96nm,静态水接触角达127°,水吸附量下降了28.8%,具有更高的水热稳定性,并进行了S-1硅烷化改性机理分析。

Pure-silica molecular sieve （S-1） were synthesized by a hydrothermal method,S-1 was modified by trie thoxyoctylsilane （OTS） in toluene. The structures and properties of samples before and after modification were characterized by FT-IR,XRD,N2 adsorption-desorption,water static contact angle, static adsorption experiment of water and n hex- ane,and hydrothermal stability experiment test. The results showed that the specific surface area,pore volume and pore diameter of ZSM-5 were 334.2m^2/g,0. 3443cm^3/g and 3. 96nm respectively,the contact angle was 127°,the water adsorption capacity fell by 28.8 %,the hydrothermal stability was enhanced. Silylated reaction mechanism of S-1 molecular sieve was studied at last.