Equilibrium solubility of CO2 in aqueous blends of 0.23 mol/kg piperazine (PZ) + 0.92 mol/kg 2-diethylaminoethanol (DEAE), 0.52 mol/kg PZ + 2.08 mol/kg DEAE, 0.92 mol/kg PZ + 3.68 mol/kg DEAE, and 1.49 mol/kg PZ + 5.96 mol/kg DEAE in the low pressure region of 0.1-65 kPa and at temperatures of 303.15-323.15 K is reported in the present article. A thermodynamic model is developed, which correlates the experimentally generated data on CO2 solubility in the newly proposed blend with an excellent agreement. Density and viscosity of DEAE + PZ + H2O have been measured at temperatures of 303.1-323.1 K and total amine mass percentage in all the blends are kept constant at 0.3. The mass % ratios of PZ/DEAE considered for measurements were 3:27, 6:24, 9:21, and 12:18. pK(a) of aqueous DEAE solution are reported in 298.15-333.15 K temperature range. Generated density data are correlated using Redlich-Kister equation, Grunberg and Nissan, and Gonzalez-Olmos, and Iglesias type model's and viscosity data are correlated using Grunberg and Nissan model.