Carbon nanotube supported oriented metal organic framework membrane for effective ethylene/ethane separation

• Published in: Science advances Vol. 8; no. 7; p. eabm6741
• Main Authors: Wei, Ruicong, Liu, Xiaowei, Zhou, Zongyao, Chen, Cailing, Yuan, Youyou, Li, Zhen, Li, Xiang, Dong, Xinglong, Lu, Dongwei, Han, Yu, Lai, Zhiping
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 18.02.2022
• Subjects: Engineering; Materials Science; Physical and Materials Sciences; SciAdv r-articles
• ISSN: 2375-2548; 2375-2548
• DOI: 10.1126/sciadv.abm6741

Zeolitic imidazolate framework 8 (ZIF-8) is effective for C 3 H 6 /C 3 H 8 separation because of the “sieving effect” of a six-membered (6-M) window. Here, we demonstrate that ZIF-8 is a versatile material that could effectively separate C 2 H 4 from C 2 H 6 via its 4-M window along the direction. We established a facile and environmentally friendly carbon nanotube (CNT)–induced oriented membrane (CNT-OM) approach to fabricate a {100}-oriented ZIF-8 membrane (100-M). In this approach, 2-methyimidazole was anchored onto the CNT surface followed by 3-hour in situ growth in aqueous solution at room temperature. The obtained 100-M, whose 4-M window is aligned along the transport pathway, showed ~3 times higher C 2 H 4 /C 2 H 6 selectivity than a randomly oriented membrane. Thus, this work demonstrates that the membrane orientation plays an important role in tuning selectivity toward different gas pairs. Furthermore, 100-M exhibited excellent mechanical stability that could sustain the separation performance after bending at a curvature of ~109 m −1 . {100}-oriented ZIF-8 membrane, induced by a 2-methyimidazole–anchored CNT support, enables superior ethylene/ethane separation.