Characteristics of mass transfer in various aqueous amino acid salt solutions for CO₂ capture

Screening test were conducted for CO₂ absorption among six potassium amino acid solutions by wetted-wall column. Potassium L-prolinate, potassium sarcosinate and potassium glycinate were picked out for further studies on mass transfer characteristics. The effects of concentration, CO₂ loading, temperature and total pressure on mass transfer properties were analyzed. The liquid phase mass transfer coefficient increases with the increase of temperature and concentration of amino acid salt solutions. The Arrhenius plots between the rate constant and temperature were obtained. Liquid phase mass transfer coefficient decreases when CO₂ loading rises. The elevated total pressure shows positive effect on CO₂ absorption. The gas phase mass transfer coefficient decreases with the elevated total pressure. The gas phase mass transfer coefficient decreases by 86% from 0.1 MPa to 0.3 MPa.