July 2025

Journal

Performance Degradation of Amine-Infused Fiber Sorbents for Direct Air Capture: Mechanisms and Solutions

By:
Wang, Yuxiang; Marreiros, Joao; Thompson, Joshua A; Toops, Todd J; Campbell, Zachary; Kidder, Michelle K; Janke, Christopher J; Sholl, David S; Lively, Ryan
Journal Name:
Industrial & Engineering Chemistry Research
Page Number:
13512-13518
Volume:
64
Issue Number:
26
Publication Date:
July 8, 2025
View DOI Listing:
https://doi.org/10.1021/acs.iecr.5c00462

Abstract

Sorbent stability poses significant impacts on long-term performance of direct air capture (DAC) of CO2 and levelized cost of capture (LCOC). We report the DAC performance degradation of amine-infused fiber sorbents based on poly(ethylenimine) (PEI), mesoporous SiO2, and cellulose acetate (CA) over CO2 cyclic sorption cycles in a nonoxidative environment. Infrared and nuclear magnetic resonance spectra indicate that the aminolysis reactions between CA ester moieties and PEI amine sites lead to the formation of acetamides and hence lower CO2 affinities of the sorbents. This stability issue can be remedied by hydrolysis treatment of the CA fiber sorbents before PEI impregnation or replacing CA with poly(ether sulfone). This study underscores the importance of selecting proper support or additive materials of DAC contactors that are compatible with active species of CO2 capture.