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Title: Inverse CO 2 /C 2 H 2 Separation with MFU‐4 and Selectivity Reversal via Postsynthetic Ligand Exchange
Abstract

Although many porous materials, including metal–organic frameworks (MOFs), have been reported to selectively adsorb C2H2in C2H2/CO2separation processes, CO2‐selective sorbents are much less common. Here, we report the remarkable performance ofMFU‐4(Zn5Cl4(bbta)3, bbta=benzo‐1,2,4,5‐bistriazolate) toward inverse CO2/C2H2separation. The MOF facilitates kinetic separation of CO2from C2H2, enabling the generation of high purity C2H2(>98 %) with good productivity in dynamic breakthrough experiments. Adsorption kinetics measurements and computational studies show C2H2is excluded fromMFU‐4by narrow pore windows formed by Zn−Cl groups. Postsynthetic F/Clligand exchange was used to synthesize an analogue (MFU‐4‐F) with expanded pore apertures, resulting in equilibrium C2H2/CO2separation with reversed selectivity compared toMFU‐4.MFU‐4‐Falso exhibits a remarkably high C2H2adsorption capacity (6.7 mmol g−1), allowing fuel grade C2H2(98 % purity) to be harvested from C2H2/CO2mixtures by room temperature desorption.

 
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NSF-PAR ID:
10403041
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
18
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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