Physicochemical properties and CO2 absorption performance of poly(ethylene glycol) 300 + hydroxyethyl ethylenediamine mixed solution

Density ( ρ ) and viscosity ( η ) data of the polyethylene glycol 300 (PEG300) and hydroxyethyl ethylenediamine (AEEA) mixed solution were measured at P  = 1005 hPa and T = (298.15–318.15) K. Following these data, Jouyban-Acree model exhibited superior correlation to density in the mixed system compared to nonlinear least square method, while the McAllister four-body equation yielded a better fitting for kinematic viscosity than other models. Utilizing ρ and η data, the Redlich-Kister equation was employed for the systematic computation and analysis of excess molar volume ( V m E ), excess activation Gibbs free energy ( Δ G *E ), partial molar volumes ( V 1 ¯ and V 2 ¯ ), and viscosity deviation ( Δη ) in the PEG300 (1) + AEEA (2) mixed solution. These excess properties indicated the advantageous nature of intermolecular binding in the PEG300 (1) + AEEA (2) mixed solution, further substantiated on the basis of various spectroscopic characterizations. Finally, under conditions of CO 2 flow rate at 150 mL/min, absorption experiments were conducted for 4 h in the PEG300 (1) + AEEA (2) mixed solution, pure AEEA, and pure PEG300, which indicated that the mixed solution exhibited the highest CO 2 absorption capacity of 0.95 mol CO 2 /mol AEEA, demonstrating superior absorption performance compared to the two pure substances.