Comparison of physicochemical properties of choline chloride-based deep eutectic solvents for CO2 capture: Progress and outlook

For green chemistry processes, the choice of solvent plays a strategic role. So, to have a sustainable environment, Deep Eutectic Solvents (DESs) emerged as a green medium solvent for CO2 capture because of their high absorption capacity. DES stand out among all the traditional solvents, as it meets the standard criteria of being benign, inexpensive, non-toxic, biodegradable and 100 % atom economic efficient. In this minireview, the comparison of Choline Chloride based-DESs with three commonly used Hydrogen bond donor molecules like Urea, Ethylene Glycol, and Glycerol have been made. The fundamental fluid and electrical properties of the mentioned DESs, like density, viscosity, conductivity, and CO2 solubility depends on the Hole theory; which is being reported for understanding the mobility of ions and their interaction with the molecules. So, this review aims at demonstrating the parameters for synthesizing the efficient DESs with low viscosity and how these approaches can be improved for high CO2 absorption capacity.