膜科学与技术

高性能聚酰亚胺氧/氮分离膜的设计与制备

作者：于道明，李凯华，董昊，李玘璇，吉文慧，宋俊，马小华

单位： 1.天津工业大学材料科学与工程学院省部共建分离膜与膜过程国家重点实验室，天津300387

关键词：聚酰亚胺；空气富氧；膜分离；不对称膜；复合膜

出版年,卷(期):页码： 2021,41(6):67-74

摘要：

以9,9-双(4-氨苯基)芴（FDA）, 4, 4' -(六氟异亚丙基）二邻苯二甲酸酐（6FDA）和均苯四甲酸酐（PMDA）为单体采用高温一步法制备了一种三元聚酰亚胺6FDA/PMDA-FDA。通过核磁和红外验证了产物的结构。该聚酰亚胺具有良好的溶解性和热稳定性。通过使用非溶剂诱导相分离（NIPS）法控制相转化时间来调控不对称膜的活性层厚度，然后再在该膜表面涂覆聚二甲基硅氧烷（PDMS）涂层来制备复合膜。通过扫描电镜确定了活性层厚度，用EDS 测试了PDMS涂层的厚度和分布。分别测试了该PI的基膜、各向异性膜和复合膜的氧/氮气分离性能，结果表明，在30 s的相转化时得到的M3拥有最佳的气体渗透性，其氧气的通量达到了25 GPU，氧/氮选择性达到了5.4，其复合膜的氧气通量达到了17.8 GPU，氧/氮选择性达到了7.0。在膜法富氧方面显示出了非常重要的应用前景。

A novel polyimide was synthesized from 9,9’-fluorene-4,4’-diamine, pyromellitic dianhydride and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride by a one-pot high temperature method. The resulting polyimide (6FDA/PMDA-FDA) was confirmed by 1H NMR and FT-IR. This PI showed good solubility, and thermal stability. The anisotropic membrane was obtained by non-solvent induced phase separation (NIPS) method, and the thickness of the skin layer was controlled by the evaporation time of the casting solvent before dip into water. The anisotropic membrane was thereafter coated with a thin layer of PDMS, the thickness of the active layer, composite layer and the distribution of the silicon were analyzed by SEM/EDX. The resulting membrane of M3 exhibited an O2 flux of 25 GPU and O2/N2 selectivity of 5.3. Additionally, the flux of O2 for C3 is 17.8 GPU and the O2/N2 selectivity reaches as much as 7, indicating a good potential for O2 enrichment from air.

于道明（1996-），男，辽宁大连人，研究生。E-mail：ydmchungha@163.com。

参考文献：

[1] 沈光林. 膜法富氧在国内应用新进展 [J]. 深冷技术, 2006, 4(1): 1-6.
[2] 尚殿英. 富氧燃烧节能新技术富氧膜 [J]. 现代节能, 1990, 4(1): 49-51.
[3] LI G Q, KUJAWSKI W, VALEK R, et al. A review - The development of hollow fiber membranes for gas separation processes [J]. Int. J. Green. Gas Con., 2021,104:103195
[4] 刘光仙, 孙晓然. 富氧膜技术的进展 [J]. 化学工程师, 2006, 4(12): 33-37.
[5] 辛志玲, 赵基钢, 张大全, et al. 富氧膜材料的研究进展与应用 [J]. 化工科技, 2009, 17(2): 45-49.
[6] Baker RW. Future directions of membrane gas separation technology [J]. Ind. Eng. Chem. Res. 2002, 41(6): 1393-1411.
[7] KOROS W J, LIVELY R P. Water and beyond: expanding the spectrum of large-scale energy efficient separation processes [J]. Aiche J, 2012, 58(9): 2624-2633.
[8] KOROS W J. Evolving beyond the thermal age of separation processes: Membranes can lead the way [J]. Aiche J, 2004, 50 (10): 2326-2334
[9] 饶华新, 张子勇, 余祥正. 环状分子交联剂的合成及其改性硅橡胶膜的富氧性能 [J]. 膜科学与技术, 2006, 4(1): 15-19.
[10] ZHU Z, ZHU J, LI J, et al. Enhanced Gas Separation Properties of Tröger’s Base Polymer Membranes Derived from Pure Triptycene Diamine Regioisomers [J]. Macromolecules, 2020, 53(5): 1573-1584.
[11] MA C H, KOROS W J. Physical aging of ester-cross-linked hollow fiber membranes for natural gas separations and mitigation thereof [J]. J. Membr. Sci., 2018, 551:214-221.
[12] XU L R, ZHANG C, RUNGTA M, et al. Formation of defect-free 6FDA-DAM asymmetric hollow fiber membranes for gas separations [J]. J. Membr. Sci., 2014, 459: 223-232.
[13] CHEN C C, QIU W L, MILLER S J, et al. Plasticization-resistant hollow fiber membranes for CO2/CH4 separation based on a thermally crosslinkable polyimide [J]. J. Membr. Sci., 2011, 382 (1-2): 212-221.
[14] FENG X, SHAO P, HUANG R, et al. A study of silicone rubber/polysulfone composite membranes: correlating H2/N2 and O2/N2 permselectivities [J]. Sep. Purif. Technol., 2002, 27(3): 211-223.
[15] KIM K J, PARK S H, SO W W, et al. CO2 separation performances of composite membranes of 6FDA-based polyimides with a polar group [J]. J. Membr. Sci., 2003, 211(1): 41-49.
[16] ZHANG L, HE G, ZHAO W, et al. Effect of formamide additive on the structure and gas permeation performance of polyethermide membrane [J]. Sep. Purif. Technol, 2010, 73(2): 188-193.
[17] WOOK, CHOI, PRAVIN, et al. Facilitated transport hollow fiber membrane prepared by t-Bu CoSalen for O2/N2 separation [J]. Microchem. J, 2017,132: 36-42
[18] ROSLAN R A, LAU W J, SAKTHIVEL D B, et al. Separation of CO2/CH4 and O2/N2 by polysulfone hollow fiber membranes: effects of membrane support properties and surface coating materials [J]. J. Membr. Eng, 2018, 38 (9): 871-880
[19] DONG S, WANG Z, SHENG M, et al. Scaling up of defect-free flat membrane with ultra-high gas permeance used for intermediate layer of multi-layer composite membrane and oxygen enrichment [J]. Sep. Purif. Technol, 2020, 239:116580.

服务与反馈：

【文章下载】【加入收藏】

《膜科学与技术》编辑部地址：北京市朝阳区北三环东路19号蓝星大厦邮政编码：100029 电话：010-64426130/64433466 传真：010-80485372邮箱：mkxyjs@163.com