Initial solubility & density evaluation of Non-Aqueous system of amino acid salts for CO₂ capture: Potassium prolinate blended with ethanol and ethylene glycol

Amine scrubbing is the state of the art technology for CO₂ capture, and solvent selection can significantly reduce the capital and energy cost of the process. Higher energy requirement for aqueous amine based CO₂ removal process is still a most important downside preventive its industrial deployment. Therefore, in this study, novel non-aqueous based amino acid salt system consisting of potassium prolinate, ethanol and ethylene glycol has been studied. This work presents initial CO₂ solubility study and important physical properties i.e. density of the studied solvent system. Previous work showed that non-aqueous system of potassium prolinate and ethanol has good absorption rates and requires lower energy for solvent regeneration. However, during regeneration, solvent loss issues were found due to lower boiling point of the ethanol. Therefore, ethylene glycol was added into current studied system for enhancing the overall boiling point of the system. The good initial CO₂ solubility and low density of studied solvent system offers several advantages as compared to conventional amine solutions.