化工学报 ›› 2025, Vol. 76 ›› Issue (5): 2209-2218.DOI: 10.11949/0438-1157.20241190

• 分离工程 • 上一篇    下一篇

超薄取向ZIF-8膜的制备及乙烯/乙烷高效分离

花敬贤(), 罗宇荣, 顾亚伟, 吴婷婷, 潘宜昌(), 邢卫红   

  1. 南京工业大学化工学院,材料化学工程国家重点实验室,江苏 南京 211816
  • 收稿日期:2024-10-25 修回日期:2024-12-05 出版日期:2025-05-25 发布日期:2025-06-13
  • 通讯作者: 潘宜昌
  • 作者简介:花敬贤(1996—),男,博士研究生,huajingxian@njtech.edu.cn
  • 基金资助:
    国家自然科学基金项目(21921006);中国石化科技部种子计划项目(223283)

Preparation of ultra-thin oriented ZIF-8 membrane for efficient ethylene/ethane separation

Jingxian HUA(), Yurong LUO, Yawei GU, Tingting WU, Yichang PAN(), Weihong XING   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, Jiangsu, China
  • Received:2024-10-25 Revised:2024-12-05 Online:2025-05-25 Published:2025-06-13
  • Contact: Yichang PAN

摘要:

金属有机框架(MOFs)作为新兴的膜材料,其变革发展正逐渐推动膜分离技术迈向1 nm尺度的精准分子分离。ZIF-8是至今研究最广泛的MOF膜材料之一,其晶体学<100>方向具有四元环孔口,临界直径介于乙烯和乙烷分子动力学直径之间。利用表面活性剂辅助合成策略制备{100}取向ZIF-8纳米薄片,并以此为基本构建模块制备{100}取向的超薄ZIF-8膜用于乙烯/乙烷的分离。膜的微结构表征与分离性能测试结果表明,得益于取向膜内形成了高度定向的四元环孔道且无晶界缺陷,实现了对乙烯/乙烷的精准分离。在25℃和101 kPa条件下,乙烯/乙烷分离选择性达6.8,乙烯渗透速率达7.33×10-8 mol/(m2·s·Pa),且连续运行100 h无性能衰减。为推进MOF膜在同碳数烃等分子分离领域的理论与技术发展奠定基础。

关键词: 膜分离, 金属有机框架, ZIF-8膜, 取向, 乙烯/乙烷

Abstract:

As an emerging membrane material, the evolution of metal organic frameworks (MOFs) is gradually driving membrane separation technology towards precise molecular separation at the 1-nanometer scale. Zeolitic imidazolate framework-8 (ZIF-8), one of the most widely studied MOF materials, features a four-membered ring pore in the crystallographic <100> direction, with a critical diameter about 0.38 nm between the kinetic diameters of C2H4 and C2H6. A surfactant-assisted synthesis strategy was employed to synthesis {100}-oriented ZIF-8 nanosheets, which were used as building blocks to fabricate ultrathin, highly oriented ZIF-8 membrane. Microstructural characterizations and C2H4/C2H6 separation tests showed that the ZIF-8 membrane with highly oriented four-membered ring pores achieved precise C2H4/C2H6 separation. Under the conditions of 25℃ and 101 kPa, the ethylene/ethane separation selectivity reaches 6.8, the ethylene permeation rate reaches 7.33×10-8 mol/(m2·s·Pa), and there is no performance degradation after continuous operation for 100 h. This work establishes the foundation for advancing both the theory and technology of MOF membranes in the separation of same-carbon-number hydrocarbon mixtures.

Key words: membrane separation, metal-organic framework, ZIF-8 membrane, orientation, C2H4/C2H6

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