Physicochemical Properties of Aqueous 2-Aminoethanoic Acid and N,N-Dimethyl-1,3-Diaminopropane as an Absorbent for Carbon Dioxide Capture

The objective of this study is to measure the physicochemical properties of 2-aminoethanoic acid (glycine, GLY) and N,N-dimethyl-1,3-diaminopropane (DMAPA) solution, which are important parameters for designing an efficient CO2 absorption system. Density meter, refractometer, tensiometer, and viscometer were used to measure the physicochemical properties of 0.1-2.0 M (mass fraction between 0.016 to 0.32) GLY-DMAPA at temperatures ranging from 298.15 to 323.15 K at 0.1 MPa. The results were represented by empirical correlations as functions of both temperature and concentration. The experimental results revealed that the physicochemical properties of the absorbents decreased as a function of temperature. Moreover, the density, refractive index, and viscosity of the absorbent increased as the concentration of the absorbent increased. In contrast, the surface tension of the absorbent showed an opposite trend as the concentration of GLY-DMAPA increased. The experimental data were consequently well represented by the empirical correlations whereby low standard deviations were reported. Moreover, the regression coefficients were reported to be close to 1, which indicated that the correlation fit well within the experimental data.