Solubilities of carbon dioxide in the eutectic mixture of levulinic acid (or furfuryl alcohol) and choline chloride

• Solubilities of carbon dioxide in six renewable deep eutectic solvents (DESs) have been reported.
• The experimental data were well correlated by Henry’s law.
• The dissolution Gibbs free energy, enthalpy, and entropy changes were derived.
• The absorption capacities of CO2 in present DESs and other DESs as well as several ionic liquids were compared.

The solubilities of carbon dioxide (CO2) in the renewable deep eutectic solvents (DESs) containing levulinic acid (or furfuryl alcohol) and choline chloride were determined at temperatures (303.15, 313.15, 323.15, and 333.15) K and pressures up to 600.0 kPa using an isochoric saturation method. The mole ratios of levulinic acid (or furfuryl alcohol) to choline chloride were fixed at 3:1, 4:1 and 5:1. Standard Gibbs free energy, dissolution enthalpy and dissolution entropy were calculated from Henry’s law constant of CO2 in the DESs. Results indicated that levulinic acid based DESs are more effective to capture CO2 than furfuryl alcohol based ones. The solubility of CO2 in the DESs increased with increasing mole ratio of levulinic acid (or furfuryl alcohol) to choline chloride as well as pressure and decreased with increasing temperature.