Investigation of Thermodynamic Properties on CO2 Absorbents Blended with Ammonia, Amino Acids, and Corrosion Inhibitors at 313.15, 333.15, and 353.15 K

The wet absorption method is currently one of the key technologies employed for the capture of carbon dioxide. In this method, the selection of an optimal absorbent is of particular importance. As such, we herein propose a series of novel and efficient absorbents based on a 7 wt % NH3 solution containing 3 wt % amino acid (beta-alanine or L-arginine) and 1 wt % corrosion inhibitor (imidazole or 1,2,3-benzotriazole). To investigate the thermodynamic properties including density, viscosity, diffusivity of CO2, kinetic constant, rate equation, and physical and chemical CO2 solubility data on capturing carbon dioxide in these absorbents, various experiments were conducted on each absorbent at 313.15, 333.15, and 353.15 K. All of the proposed absorbents showed better capacity than monoethanolamine which has been most widely used as a wet absorbent. Among them, the absorbents with added L-arginine were found to be superior to absorbents with added beta-alanine.