Absorption, desorption and interaction of SO2 with the binary system tetraethylene glycol + dimethyl sulfoxide

The gas-liquid equilibrium (GLE) data were determined for the mixture SO2 + N2 in the binary system of tetraethylene glycol (TeEG) + dimethyl sulfoxide (DMSO) at T = 298.15–313.15 K and p = 123.15 kPa with the SO2 partial pressures of 0.4–150 Pa. From GLE data, Henry’s law constants (HLCs) were obtained. When the SO2 concentration in the gas phase was designed at ySO2 = 500 ppmv, the SO2 solubility in the binary system is located in a minimum of 9.36 mol m−3 in TeEG and a maximum of 80.34 mol m−3 in DMSO. The SO2 absorption process was reversible from the five absorption–desorption cycles, and the solvents could repeat utilisation without obvious loss of absorption capacity and the homologous SO2 desorption efficiency was nearby 98.7%. Furthermore, the spectral consequences illustrated that H-bonding was formed among TeEG, DMSO and SO2.