Carbon Dioxide Capture and Utilization by Alkanolamines in Deep Eutectic Solvent Medium

The major drawback of the aqueous alkanolamine-based carbon dioxide capture process is the high energy penalty for the regeneration of the absorbent. To overcome this weakness, we studied the absorption of CO 2 in alkanolamines dissolved in greener and nontoxic deep eutectic solvents. Among the alkanolamines in various deep eutectic solvent media, 2-amino-2-methyl-1-propanol in choline chloride: urea (1:2) medium was found to exhibit the highest absorption capacity for CO 2 gas. In addition to that, the value-added product, 2-amino-2-methyl-1-propanol carbamate, was obtained from all deep eutectic solvent medium, which was analyzed by Fourier transform infrared and 1 H and 13 C nuclear magnetic resonance spectroscopic techniques. Under optimized conditions, the maximum yield of 82%, 2-amino-2-methyl-1-propanol carbamate was obtained. The deep eutectic solvent used for the process has been recovered and reused for 4 cycles. Thus, the 2-amino-2-methyl-1-propanol in deep eutectic solvent medium emerges to be a novel promising candidate for capture as well as for the utilization of the CO 2 gas to obtain the value-added product.