Double bond carboxylate ionic liquids for reversible SO2 capture

Solubility of SO 2 in [N 2224 ][Met] was measured at temperature from 313.2 to 333.2 K and pressure up to 1.8 bar. The [N 2224 ][Met] absorbed SO 2 at high speed and could be recycled for four times. The Reaction Equilibrium Thermodynamic Model (RETM) was used to correlate the experimental data, Henry’s constant ( H ), reaction equilibrium constant ( K 0 ), and thermodynamic properties ( Δ r H m 0 , Δ r G m 0 , Δ r S m 0 , Δ H phy a n d Δ H chem ) were derived. Considering the absorption capacity and low absorption enthalpy, as well as the fast absorption process, [N 2224 ][Met] is thought to be a promising absorbent to ordinary solvent as a desulfurizer.