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• Diamine (DMAPA) and glycine (GLY) mixtures have high CO 2 loading capacity. • Ethanol was used to convert liquid absorbent and CO 2 into carbamates. • At low GLY-DMAPA concentration (0.1 mol/L) no product was formed. • Carbamates were generated at high concentration of GLY-DMAPA (0.5–2.0 mol/L). 3-dimethylaminopropylamine (DMAPA) and glycine (GLY) mixture was studied as a potential absorbent for carbon dioxide (CO 2) capture and utilization. The solubility of CO 2 in aqueous GLY-DMAPA solutions within the range of 0.1–2.0 mol/L (M) were measured experimentally using pressure differential technique. Utilization of CO 2 was also studied by mixing the CO 2 -saturated absorbent with ethanol. The final products obtained were characterized by using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The solubility study revealed that the CO 2 loading capacity increased as pressure of CO 2 increased. In contrast, the loading capacity decreased when concentration of the absorbent and temperature in equilibrium cell increased. However, the total moles of CO 2 absorbed showed an opposite trend such that net CO 2 absorbed increased as concentration of absorbent increased. The chemical interactions between CO 2 and GLY-DMAPA molecules were studied by analyzing the changes of characteristic peaks observed form the FTIR spectra. For CO 2 utilization, the addition of ethanol as a reagent into 0.1 M CO 2 -saturated GLY-DMAPA solution did not produced any precipitate. Nonetheless, as the concentration of GLY-DMAPA increased from 0.5 M to 2.0 M, white precipitates were produced, indicated that the conversion of CO 2 into solid compounds occurred instantaneously after the CO 2 capture. The optimum concentration of GLY-DMAPA for CO 2 capture and utilization depends on the amount of solids generated and the CO 2 loading capacity of the absorbent. At 5 bar, the optimum concentration was found to be 1.0 M with 45 mg/g of solids recovered and CO 2 loading capacity of 1.6 mol CO 2 /mol absorbent. The final product was identified as carbamate salt based on the main characteristic peaks present on the FTIR and XPS spectra. [ABSTRACT FROM AUTHOR]