采用原位水热合成法，直接用四丙基氢氧化铵（TPAOH）/四乙氧基硅烷（TEOS）/H2O合成液在具有较大孔径（约0.1μm）的多孔玻璃载体表面合成b轴取向MFI型分子筛膜。考察了载体的放置方式对成膜的影响，结果表明，将多孔玻璃完全浸入合成液中时，载体表面只能得到零星分布的MFI型分子筛晶体；而将多孔玻璃部分浸入合成液中时，在液面以上的载体表面获得了b轴取向MFI型分子筛膜，靠近液面的载体表面形成的 MFI型分子筛膜比较致密。优化了合成液的配比和合成时间，发现采用合成液配比为0.64TPAOH：1TEO S：165H2O时165℃合成3 h，可以在多孔玻璃表面形成大面积连续的b轴取向MFI型分子筛膜。当合成时间延长至6h时，MFI型分子筛膜层连续致密，但呈现随机取向。%b-Oriented MFI-type zeolite membranes are prepared directly on porous glass supports (pore size 0.1 μm) by in situ hydrothermal synthesis method with the synthesis system of TPAOH/TEOS/H2O. The effect of the position of the support in the synthesis solution on the membrane formation is investigated. Only a small amount of discrete MFI-type zeolite crystals are obtained if the porous glass is immersed in the synthesis solution completely. When the support is partly immersed in the synthesis solution, b-oriented MFI-type zeolite membrane can be observed on the un-immersed support surface and the membrane is denser near the liquid level. The preparation parameters such as the synthesis solution composition and crystallization time are systematically investigated. Under the optimized synthesis condition (0.64TPAOH:1TEOS:165H2O, 165 ℃ 3 h), b-oriented MFI-type zeolite membrane with high coverage is achieved on the porous glass surface. When the crystallization time is extended to 6 h, the support can be fully covered by zeolite MFI membrane, however, the membrane is randomly oriented.
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