Development of carbon dioxide separation process using continuous hollow-fiber membrane contactor and water-splitting electrodialysis

Abstract

Studies on the development of carbon dioxide (CO₂) separation process using continuous hollow-fiber membrane contactor (HFMC) and water-splitting electrodialysis (WSED) as an alternative method for the conventional processes are reported. Several experiments for CO₂ recovery and absorbent regeneration using HFMC–WSED hybrid system were performed. In this study, four widely used absorbents (KOH, NaOH, K₂CO₃, and N-methyldiethanolamine) were examined and compared in terms of the process efficiency. The results showed that KOH was the best absorbent for this hybrid system due to its high ionic conductivity. In addition, several operational problems including the proton leakage and gas molecule diffusion through the membranes were considered. The results of continuous experiments showed that the continuous recovery of CO₂-rich absorbents was reliably performed during the tests without any problem.