Solubility measurements of carbon dioxide (CO2) in aqueous 2-(2-aminoethylamino)ethanol (AEEA, 15 wt %), AEEA + N-methyldiethanolamine (MDEA, 5, 10 wt %), and AEEA + 2-amino-2-methyl-1-propanol (AMP, 5, 10 wt %) solutions as CO2 absorbents were performed at CO2 partial pressure from (0.8 to 800) kPa and temperatures of (303, 313, and 323) K. With increasing the MDEA/AMP amount to AEEA, CO2 loading of the absorbents decreased, while the absorption rate increased. At low CO2 partial pressure (<30 kPa), the loading of AEEA + AMP was higher than that of AEEA + MDEA, while at high CO2 partial pressure (> 100 kPa), the loading of AEEA + AMP was lower than that of AEEA + MDEA at the same concentration. Furthermore, the absorption rate was in the order AEEA + AMP > AEEA + MDEA > AEEA.