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Title: ZIF‐8 Membrane Separation Performance Tuning by Vapor Phase Ligand Treatment
Abstract Vapor phase ligand treatment (VPLT) of 2‐aminobenzimidazole (2abIm) for 2‐methylimidazole (2mIm) in ZIF‐8 membranes prepared by two different methods (LIPS: ligand induced permselectivation and RTD: rapid thermal deposition) results in a notable shift of the molecular level cut‐off to smaller molecules establishing selectivity improvements from ca. 1.8 to 5 for O2/N2; 2.2 to 32 for CO2/CH4; 2.4 to 24 for CO2/N2; 4.8 to 140 for H2/CH4and 5.2 to 126 for H2/N2. Stable (based on a one‐week test) oxygen‐selective air separation performance at ambient temperature, 7 bar(a) feed, and 1 bar(a) sweep‐free permeate with a mixture separation factor of 4.5 and oxygen flux of 2.6×10−3 mol m−2 s−1is established. LIPS and RTD membranes exhibit fast and gradual evolution upon a 2abIm‐VPLT, respectively, reflecting differences in their thickness and microstructure. Functional reversibility is demonstrated by showing that the original permeation properties of the VPLT‐LIPS membranes can be recovered upon 2mIm‐VPLT.  more » « less
Award ID(s):
1705687
PAR ID:
10119439
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
58
Issue:
46
ISSN:
1433-7851
Format(s):
Medium: X Size: p. 16390-16394
Size(s):
p. 16390-16394
Sponsoring Org:
National Science Foundation
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