Investigation of Amine-Based Ternary Deep Eutectic Solvents for Efficient, Rapid, and Reversible SO2 Absorption

Effective and reversible absorption of sulfur dioxide (SO2) with commercially available and easily prepared absorbents now has drawn increasing concentration. In this work, a series of amine-based ternary deep eutectic solvents (DESs) composed of diethylenetriamine (DETA), acetamide (AA), and ethylene glycol (EG) were prepared to study the SO2 absorption performance. Results demonstrate that these obtained ternary DESs not only exhibit a rapid absorption rate but also present desirable absorption capacity and cycling performance. Mass capacity of 0.82 g of SO2/g of DES would be received with DETA/AA/EG (1:1:2) ternary DES, which could be ascribed to the Lewis acid–base interaction and hydrogen bonding between alkaline ternary DES and acidic SO2. This work would provide a novel route to prepare ideal absorbents for effective SO2 capture.