Absorption of dilute sulfur dioxide in aqueous poly-ethylene glycol 400 solutions at T = 308.15 K and p = 122.60 kPa

Isothermal (gas + liquid) equilibrium (GLE) data at T = 308.15 K and p = 122.60 kPa are reported for the absorption of dilute SO2 in various aqueous poly-ethylene glycol 400 (PEG) solutions, in which SO2 partial pressures are in the range of (0.9 to 92) Pa. Measurements are carried out by a saturation method using a glass absorption apparatus, which was controlled at constant temperatures by a thermostatic circulation bath with a Beckmann thermometer. The GLE data were obtained with uncertainties within 0.02 K for temperature, 0.1 kPa for total pressures, 3% for SO2 concentration in the gas phase, and 0.6% for SO2 concentration in the liquid phase. The measurements show that the solubility of dilute SO2 in the system of {PEG (1) + water (2)} increases with increasing PEG concentration in the mass fraction range of w1 = (0.40 to 1.00), and the solubility of SO2 in the system of {PEG (1) + water (2)} presents an extreme minimum at the mass fraction of w1 = 0.40 of 190 mg · L−1 when SO2 in the gas phase is designed at ΦSO2ΦSO2 = 5 · 10−4. The peculiarity of this work is used to provide important GLE data for the design and operation of the absorption and desorption process in flue gas desulfurization (FGD) with potential industrial application of the solutions containing PEG.

► Isothermal (gas + liquid) equilibrium (GLE) data at T = 308.15 K and p = 122.60 kPa.
► Solubility of SO2 in pure PEG 400 presented an extreme maximum of 951 mg · L−1.
► Solubility of SO2 in w1 = 0.40 PEGW is an extreme minimum of 190 mg · L−1.