Evaluation of hybrid amines and alcohol solvent with ion-exchange resin catalysts for energy-efficient CO2 capture

Abstract

The traditional carbon dioxide (CO₂) desorption process in amine-based carbon capture requires high regeneration energy consumption, a factor that has severely limited its application. In this work, cation exchange resin catalysts are tested as a novel approach to accomplish improvement in aqueous monoethanolamine (MEA) regeneration in terms of the CO₂ desorption rate, amount of CO₂ released and relative heat duty. The results indicate that the cation exchange resin Amberlyst-15 significantly increased the amine regeneration rate and improved the amount of CO₂ desorbed by 21%. A possible catalytic mechanism is proposed. In addition, the solvent effects of methanol and ethanol were also explored for low temperature and energy-saving CO₂ desorption technology. In the case of a mixed 12.5 wt% ethanol and 2 wt% Amberlyst-15 catalyst, the system exhibited a reduction of 59% in the energy demand of CO₂ desorption compared with the 5 M MEA baseline. To sum up, this work provides an efficient strategy for MEA regeneration at low temperature, thus reducing the energy consumption for CO₂ capture.