The reaction rates of CO2 in an aqueous blend of amine solutions of N-(2-hydroxethyl)piperazine (N-HEPZ) and 2-amino-2-hydroxymethyl-1,3-propanediol (AHPD) at 298?K were investigated in a concentration range of 0.00250.03?kmol?m3 N-HEPZ with a blend of 1?kmol?m3 AHPD. The reaction was modeled using a termolecular reaction mechanism with a rate of 12?971?m3kmol1s1. The results indicate that the blended aqueous solution of N-HEPZ and AHPD is a potential candidate as an alternative solvent for CO2 absorption, where the sterically hindered AHPD increases the CO2 capacity and the reaction rate is enhanced by the promoter, N-HEPZ.