Microporous Polyamide Membranes for Molecular Sieving of Nitrogen from Volatile Organic Compounds

• Published in: Angewandte Chemie International Edition Vol. 56; no. 21; pp. 5755 - 5759
• Main Authors: Zhou, Haoli, Tao, Fei, Liu, Quan, Zong, Chunxin, Yang, Wenchao, Cao, Xingzhong, Jin, Wanqin, Xu, Nanping
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 15.05.2017
• Edition: International ed. in English
• Subjects: Cyclohexane; Energy efficiency; Gas separation; Gases; Membrane permeability; Membranes; microporous membranes; Organic compounds; Polyamide resins; Polyamides; Polymers; Rejection rate; Separation processes; triptycene; VOCs; Volatile organic compounds; microporous membranes; polyamides; triptycene; gas separation; volatile organic compounds
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201700176

Microporous polymer membranes continue to receive tremendous attention for energy‐efficient gas separation processes owing to their high separation performances. A new network microporous polyamide membrane with good molecular‐sieving performance for the separation of N2 from a volatile organic compound (VOC) mixture is described. Triple‐substituted triptycene was used as the main monomer to form a fisherman's net‐shaped polymer, which readily forms a composite membrane by solution casting. This membrane exhibited outstanding separation performance and good stability for the molecular‐sieving separation of N2 over VOCs such as cyclohexane. The rejection rate of the membrane reached 99.2 % with 2098 Barrer N2 permeability at 24 °C under 4 kPa. This approach promotes development of microporous membranes for separation of condensable gases. A triple‐substituted triptycene microporous polyamide membrane, featuring a fisherman's net‐shaped structure, imparts the microporous material with molecular‐sieving network pores and a low driving force. The membrane displays preferential nitrogen permeation over volatile organic compounds such as cyclohexane.