PIM-1-assisted structuring of amine-functionalized porous organic copolymer for post-combustion carbon dioxide capture

Abstract

Capturing CO2 from flue gas of coal-burned power plants has been considered to be a promising technology to mitigate the environmental problems caused by rising level of CO2 at the atmosphere. Amine-functionalized adsorbents, showing impressive CO2 adsorption capability and selectivity even at low CO2 partial pressure, face the challenge of permanent structural changes and performance deterioration due to the irreversibly bonding of SO2, a common impurity of flue gas, particularly under humid condition. Besides, the reported amine-functionalized adsorbents are usually nano-sized powders, impractical for industrial applications. Therefore, the development of efficient, stable, and structured CO2 adsorbents is still an urgent need. Herein, we develop a novel structured mixed-matrix adsorbent (PIM-PP-DETA), using a diethylenediamine-appended porous organic copolymer (PP-DETA, prepared by a copolymerization reaction of dichloro-p-xylene and 4,4′-bis(chloromethyl)biphenyl and a one-step amine grafting process) as main adsorbent and PIM-1 as polymer matrix through a phase inversion process. The as-developed PIM-PP-DETA not only exhibits high CO2 adsorption capacity and outstanding CO2 selectivity over N2, but also shows fast adsorption kinetics and high stability under repeated adsorption-desorption cycling under dynamic flow conditions. Furthermore, PIM-PP-DETA possesses high tolerance towards acidic and moist environments, with CO2 adsorption capacity remained at a relatively high level after SO2 and humid exposure, suggesting its potential usage to post-combustion CO2 capture.