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Title: Highly H 2 O permeable ionic liquid encapsulated metal–organic framework membranes for energy-efficient air-dehumidification
Isothermal membrane-based air dehumidification (IMAD) is much more energy-efficient and economical than traditional air-dehumidification technologies. There are, however, no practical IMAD process technologies currently available mainly due to limitations of current membranes. Ionic liquids (ILs) are a promising air-dehumidification membrane material. Current supported IL membranes suffer from poor stability, limiting their performances. Herein, we propose new stable IL membranes, encapsulated IL membranes (EILMs) by encapsulating 1-butyl-3-methylimidazolium bromide ([C 4 MIM][Br]) into ultrathin polycrystalline UiO-66-NH 2 metal–organic framework membranes via a ship-in-a-bottle method. The stability of IL membranes is significantly enhanced due to the IL entrapped in the pore cages of UiO-66-NH 2 . The EILMs show unprecedentedly high H 2 O permeance (∼2.36 × 10 −4 mol m −2 s −1 Pa −1 ), an order of magnitude greater than that of the most permeable air-dehumidification membranes reported so far. Furthermore, the encapsulated [C 4 MIM][Br] drastically increases the H 2 O/N 2 separation factor to ∼1560, satisfying the minimally required H 2 O/N 2 separation performance for commercially viable air-dehumidification.
Award ID(s):
1929596 1510530
Publication Date:
Journal Name:
Journal of Materials Chemistry A
Sponsoring Org:
National Science Foundation
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