采用原位水热合成法在具有较高装填面积的α-Al2O3中空纤维支撑体上制备了MFI分子筛膜. 实验研究了膜合成时间及重复次数对膜质量的影响. 结果表明, 经过两次5 h合成的中空纤维MFI分子筛膜具有良好的膜结构和较优的对二甲苯(PX)渗透选择性. 同时, 系统考察了操作温度和进料分压对膜性能的影响. 结果显示, 对于PX/OX/MX(2:1:1)三元体系的分离, 150 ℃时, PX/OX和PX/MX的分离因子分别可达174、79, PX渗透性为3.7×10-9 mol/(m2?s?Pa).

MFI zeolite membranes were prepared on α-Al2O3 hollow fiber supports with high packed density by in-situ hydrothermal synthesis method. The influences of hydrothermal synthesis time and repetition times on the quality of the as-synthesized membranes were studied. It was observed that hollow fiber MFI zeolite membranes with excellent structure and para-xylene (PX) permselectivity were fabricated by twice growth for 5 h. Meanwhile, the effects of operating temperature and feed partial pressure on membrane performance were investigated systematically. As a result, the PX/OX and PX/MX separation factor up to 174 and 79 with PX permeance of 3.7×10-9 mol/(m2?s?Pa) was obtained at 150 ℃ for a PX/OX/MX (2:1:1) ternary mixture.

[1]Smitha B, Suhanya D, Sridhar S, et al. Separation of organic–organic mixtures by pervaporation – a review[J]. J Membr Sci, 2004, 241 (1):1 – 21.
[2]Hong Z, Zhang C, Gu X H, et al. A simple method for healing nonzeolitic pores of MFI membranes by hydrolysis of silanes[J]. J Membr Sci, 2011, 366 (1 – 2):427 – 435.
[3]Zhang C, Hong Z, Gu X H, et al. Silicalite–1 zeolite membrane reactor packed with HZSM–5 catalyst for meta-xylene isomerization[J]. Ind Eng Chem Res, 2009, 48:4293 – 4299.
[4]Gu X H, Dong J H, Nenoff T M, et al. Separation of p–xylene from multicomponent vapor mixtures using tubular MFI zeolite membranes[J]. J Membr Sci, 2006, 280 (1 – 2):624 – 633.
[5]Yuan Wenhui, Lin Y S, Yang Weishen. Molecular sieving MFI–type zeolite membranes for pervaporation separation of xylene isomers[J]. J Am Chem Soc, 2004, 126 (15):4776 – 4777.
[6]Keizer K, Burggraaf A J, Vroon Z A E P, et al. Two component permeation through thin zeolite MFI membranes[J]. J Membr Sci, 1998, 147 (2):159 – 172.
[7]Lai Z, Bonilla G, Diaz I, et al. Microstructural optimization of a zeolite membrane for organic vapor separation[J]. Science, 2003, 300 (5618):456 – 460.
[8]洪周, 张春, 吴再娟, 等. 原位法制备MFI分子筛膜及其渗透性能[J]. 南京工业大学学报, 2012, 34 (6):22 – 26.
[9]Tan X Y, Liu S M, Li K. Preparation and characterization of inorganic hollow fiber membranes[J]. J Membr Sci, 2001, 188:87 – 95.
[10]Daramola M O, Burger A J, Pera-Titus M, et al. Nanocomposite MFI–ceramic hollow ?bre membranes via pore–plugging synthesis: Prospects for xylene isomer separation[J]. J Membr Sci, 2009, 337 (1 – 2):106 – 112.
[11]Deng Z, Nicolas C H, Daramola M O, et al. Nanocomposite MFI–alumina hollow ?bre membranes prepared via pore–plugging synthesis: In?uence of the porous structure of hollow ?bres on the gas/vapour separation performance[J]. J Membr Sci, 2010, 364 (1 – 2):1 – 8.
[12]Deng Z, Nicolas C H, Guo Y, et al. Synthesis and characterization of nanocomposite B–MFI–alumina hollow ?bre membranes and application to xylene isomer separation[J]. Micropor Mesopor Mater, 2010, 133:18 – 26.
[13]Rouleau L, Pirngruber G, Guillou F, et al. Supported zeolite composite membranes synthesized by controlling the penetration or gelation of the precursor into the support pores[J]. Stud Surf Sci, 2008, 174:645 – 648.
[14]Wang H B, Lin Y S. Effects of synthesis conditions on MFI zeolite membrane quality and catalytic cracking deposition modi?cation results[J]. Micropor Mesopor Mater, 2011, 142 (2 – 3):481 – 488.
[15]Xomeritakis G, Gouzinis A, Nair S, et al. Growth, microstructure, and permeation properties of supported zeolite (MFI) films and membranes prepared by secondary growth[J]. Chem Eng Sci, 1999, 54:3521 – 3531.
[16]O’Brien-Abraham J, Kanezashi M, Lin Y S. Effects of adsorption–induced microstructural changes on separation of xylene isomers through MFI-type zeolite membranes[J]. J Membr Sci, 2008, 320 (1 – 2):505 – 513.
[17]Yan Y S, Davis M E, Gavalas G R. Preparation of zeolite ZSM-5 membranes by in–situ crystallization on porous α-Al2O3[J]. Ind Eng Chem Res, 1995, 34 (5):1652 – 1661.
[18]Deng Z, Nicolas C H, Guo Y, et al. Isomorphously substituted B–MFI hollow ?bre membranes for p–xylene separation from C8 aromatic mixtures[J]. Sepa Purif Tech, 2011, 80 (2):323 – 329.