Silicalite-2沸石膜以其特殊的直孔道结构和骨架中不含铝而具有强疏水性，成为潜在的优良透醇沸石膜材料。本文在大孔氧化铝载体上采用二次水热生长法，150ºC晶化72h制备出了Silicalite-2沸石膜，并在60ºC下对5 wt.%乙醇/95 wt.%水溶液进行了渗透蒸发测试，通量和分离因子分别为7.61 kg·m-2·h-1和6.7。膜材料疏水改性是提高其醇水分离性能的有效途径。本文通过在制备的沸石膜表面负载一层二氧化硅颗粒以提高表面粗糙度进一步利用三甲基氯硅烷进行修饰提高膜的疏水性。修饰后的沸石膜疏水性显著提高，水接触角为127.5°，在60ºC下对5 wt.%乙醇/95 wt.%水溶液的渗透蒸发通量和分离因子达到3.67 kg·m-2·h-1和31.4。

 Silicalite-2 zeolite membrane has strong hydrophobicity due to the special straight channels and the absence of Al element in the framework, so it can be used as a potential excellent zeolite membrane material. A secondary hydrothermal growth method was used on a macroporous alumina support to prepare the Silicalite-2 zeolite membrane by crystallization at 150℃ for 72 hours. The separation performance of Silicalite-2 zeolite membrane was studied for 5 wt.% of ethanol/water mixture at 60°C, exhibiting a flux and separation factor of 7.61 kg·m-2·h-1 and 6.7, respectively. The hydrophobic modification of membrane materials is an effective way to improve the separation performance of ethanol/water mixtures. In this paper, a layer of silica particles is loaded on the surface of the zeolite membrane, and further modified with trimethylchlorosilane to enhance its hydrophobicity. The hydrophobicity of the modified zeolite membrane is significantly improved with a water contact angle of 127.5°. Moreover, the modified membrane shows a flux and separation factor of 3.67 kg·m-2·h-1and 31.4, respectively for 5 wt.% of ethanol/water mixture at 60℃.

 [1] Hong Z, Wu Z, Zhang Y, et al. Catalytic Cracking Deposition of Methyldiethoxysilane for Modification of Zeolitic Pores in MFI/α-Al2O3 Zeolite Membrane with H+ Ion Exchange Pretreatment[J]. Industrial & Engineering Chemistry Research, 2013,52(36):13113-13119.
 [2] Kim S, Yang S, Reddy G K, et al. Zeolite Membrane Reactor for High-Temperature Water-Gas Shift Reaction: Effects of Membrane Properties and Operating Conditions[J]. ENERGY & FUELS, 2013,27(8):4471-4480.
 [3] Peng Y, Lu H, Wang Z, et al. Microstructural optimization of MFI-type zeolite membranes for ethanol-water separation[J]. JOURNAL OF MATERIALS CHEMISTRY A, 2014,2(38):16093-16100.
 [4] Lai Z P, Bonilla G, Diaz I, et al. Microstructural optimization of a zeolite membrane for organic vapor separation[J]. SCIENCE, 2003,300(5618):456-460.
 [5] Kim S, Yang S, Reddy G K, et al. Zeolite Membrane Reactor for High-Temperature Water-Gas Shift Reaction: Effects of Membrane Properties and Operating Conditions[J]. ENERGY & FUELS, 2013,27(8):4471-4480.
 [6] Dong Y, Peng Y, Wang G, et al. Corrosion-Resistant Zeolite Silicalite-1 Coatings Synthesized by Seeded Growth[J]. INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 2012,51(9):3646-3652.
 [7] KOKOTAILO G T, CHU P, LAWTON S L, et al. SYNTHESIS AND STRUCTURE OF SYNTHETIC ZEOLITE ZSM-11[J]. NATURE, 1978,275(5676):119-120.
 [8] BIBBY D M, MILESTONE N B, ALDRIDGE L P. SILICALITE-2, A SILICA ANALOG OF THE ALUMINOSILICATE ZEOLITE ZSM-11[J]. NATURE, 1979,280(5724):664-665.
 [9] Kosinov N, Hensen E J M. Synthesis and separation properties of an alpha-alumina-supported high-silica MEL membrane[J]. JOURNAL OF MEMBRANE SCIENCE, 2013,447:12-18.
[10] Kosinov N, Sripathi V G P, Hensen E J M. Improving separation performance of high-silica zeolite membranes by surface modification with triethoxyfluorosilane[J]. MICROPOROUS AND MESOPOROUS MATERIALS, 2014,194:24-30.
[11] 吴琦刚, 韶晖, 钟璟, 等. Silicalite-2分子筛膜的制备及其渗透汽化性能研究[J]. 现代化工, 2015,35(07):46-49.
[12] Lan J, Saulat H, Wu H, et al. Manipulation on microstructure of MFI membranes by binary structure directing agents[J]. Microporous and Mesoporous Materials, 2020,299:110128.
[13] Du J, Luo X, Fu Z, et al. Improving the hydrophobicity of nylon fabric by consecutive treatment with poly(acrylic acid), tetraethylorthosilicate, and octadecylamine[J]. JOURNAL OF APPLIED POLYMER SCIENCE, 2015,132(UNSP 4245634).
[14] Chai L, Yang J, Wang J, et al. Preparation of Silicalite-2 Zeolite Membrane on Macroporous Support by Seeded Steam-assisted Crystallization Method[J]. CHEMISTRY LETTERS, 2015,44(11):1592-1594.