AbstractThe 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 0.0025–0.03 kmol m–3 N‐HEPZ with a blend of 1 kmol m–3 AHPD. The reaction was modeled using a termolecular reaction mechanism with a rate of 12 971 m3kmol–1s–1. 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.