Premium
Cyclotetrabenzoin Acetate: A Macrocyclic Porous Molecular Crystal for CO 2 Separations by Pressure Swing Adsorption **
Author(s) -
Wang YaoTing,
McHale Corie,
Wang Xiqu,
Chang ChungKai,
Chuang YuChun,
Kaveevivitchai Watchareeya,
Miljanić Ognjen Š.,
Chen TengHao
Publication year - 2021
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.202102813
Subject(s) - adsorption , pressure swing adsorption , chemistry , molecule , elution , selectivity , vacuum swing adsorption , porosity , benzene , chemical engineering , flue gas , molecular dynamics , crystal (programming language) , organic chemistry , inorganic chemistry , chromatography , computational chemistry , catalysis , engineering , computer science , programming language
A porous molecular crystal (PMC) assembled by macrocyclic cyclotetrabenzoin acetate is an efficient adsorbent for CO 2 separations. The 7.1×7.1 Å square pore of PMC and its ester C=O groups play important roles in improving its affinity for CO 2 molecules. The benzene walls of macrocycle engage in an apparent [π⋅⋅⋅π] interaction with the molecule of CO 2 at low pressure. In addition, the polar carbonyl groups pointing inward the square channels reduce the size of aperture to a 5.0×5.0 Å square, which offers kinetic selectivity for CO 2 capture. The PMC features water tolerance and high structural stability under vacuum and various gas adsorption conditions, which are rare among intrinsically porous organic molecules. Most importantly, the moderate adsorbate‐adsorbent interaction allows the PMC to be readily regenerated, and therefore applied to pressure swing adsorption processes. The eluted N 2 and CH 4 are obtained with over 99.9 % and 99.8 % purity, respectively, and the separation performance is stable for 30 cycles. Coupled with its easy synthesis, cyclotetrabenzoin acetate is a promising adsorbent for CO 2 separations from flue and natural gases.