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通过共缩合和气相甲基接枝两步法制备了新型的高疏水性富含甲基的Ti-HMS介孔分子筛.采用X光衍射、N2吸附、红外光谱、硅核磁、热重、元素分析(原子发射光谱)、紫外可见光谱等手段和亲水性实验对样品进行表征,并用环己烯环氧化反应进行催化性能测试.结果表明,经过两步接枝甲基后,Ti-HMS仍保持典型的介孔结构特征,拥有较多的甲基含量和较高的疏水性,催化环己烯环氧化活性和选择性均比共缩合法(一步接枝法)Ti-HMS有所提高.
A new type of highly hydrophobic Ti-HMS mesoporous molecular sieve was prepared by co-condensation and gas-phase methyl grafting.Through X-ray diffraction, N2 adsorption, infrared spectroscopy, nuclear magnetic resonance, thermogravimetric analysis and elemental analysis (Atomic Emission Spectroscopy), UV-visible spectroscopy and other means and hydrophilicity of the samples were characterized and the catalytic performance of cyclohexene epoxidation was tested.The results show that after two steps of grafting methyl, Ti-HMS still Maintains the typical mesoporous structure characteristics, has more methyl content and higher hydrophobicity, catalytic cyclohexene epoxidation activity and selectivity than the co-condensation method (one-step grafting method) Ti-HMS increased .