Solubility of sulfur dioxide in tetraglyme-NH4SCN ionic liquid: high absorption efficiency

摘要

An easily prepared ionic liquid was synthesized by a one-step method and applied in SO _(2) absorption efficiently. The cation of the ionic liquid is a supramolecular structure consisting of NH ~(+) _(4) and tetraglyme, similar to the structure of NH ~(+) _(4) and crown ether, and the anion is selected as SCN ~(?) . The ionic liquid has good thermal stability. Under the conditions of 293 K and 1 bar, one mol ionic liquid can absorb 2.73 mol SO _(2) , which is about 30% higher than tetraglyme. The absorption mechanism was characterized using IR and NMR. And the results confirmed that the interaction mechanism between SO _(2) and the ionic liquid is a physical interaction rather than a chemical interaction.