疏水性HMS分子筛的制备及水热稳定性  

Preparation and Hydrothermal Stability of Hydrophobic HMS Molecular Sieve

作　　者：王广建[1] 韩亚飞[1] 褚衍佩 冯庆吉 王芳[1] 

机构地区：[1]青岛科技大学化工学院,青岛266042

出　　处：《硅酸盐学报》2015年第7期867-874,共8页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金项目(21276130)

摘　　要：以三甲基氯硅烷和六甲基二硅氮烷为硅烷化试剂,分别采用气相和液相硅烷化法对HMS分子筛进行表面改性制备疏水性HMS分子筛。考察了改性方法、硅烷试剂与分子筛摩尔比、反应温度和时间对硅烷化效果的影响,研究了改性前后HMS的骨架特征、微观结构和疏水性、水热稳定性。结果表明:气相硅烷化法较液相法优势明显,硅烷化程度和效率均较高;在双硅烷化试剂、反应温度90℃、硅烷试剂与分子筛摩尔之比0.8、反应时间8 h等条件下,改性前后HMS的静态水吸附量分别为45.46%和1.38%,疏水性得到明显提高。HMS经硅烷化改性后保持介孔骨架结构和蠕虫状孔道,同时水热稳定性得到有效改善,800℃水蒸气处理6 h后介孔结构仍然存在。The hydrophobic HMS molecular sieve was prepared with trimethylchlorosilane and hexamethyldisilazane as silane agents by a vapor silylation method and a liquid silylation method. The effects of modification modes, reaction temperature and time, molar ratio of silane agents to HMS on the silylation were investigated. The framework character, microstructures and hydrophobic property, hydrothermal stability of HMS before and after modification were also analyzed. The results indicate that the gas phase method has some advantages such as its high efficiency and degree of silanization. The static water adsorption capacity of HMS before and after silanization are 45.38% and 1.38%, respectively, and the hydrophobic of HMS is enhanced under the optimal conditions （i.e., use of mixed silane agents, reaction temperature of 90 , reaction time of 8 h, and molar ratio of silane agents to HMS of 0.8）. The℃hydrophobic HMS maintains the mesoporous structure and typical vermicular channel of HMS molecular sieve. Also, the hydrothermal stability of HMS is improved efficiently after modification, and the mesoporous structure is retained even after treatment by water vapor at 800℃ for 6 h.

关 键 词：HMS 分子筛 硅烷化 改性 疏水性 水热稳定性 

分 类 号：O613.7[理学—无机化学]