Solubility of N2O and CO2 in Dimethyl Sulfoxide, 2-(Butylamino)ethanol, and Their Water-Lean Blends

The water-lean absorbent of dimethyl sulfoxide (DMSO)/2-(butylamino)ethanol (BAE)/H2O has recently been proposed for energy-efficient CO2 capture. The CO2/N2O analogy method can provide important fundamental data for its kinetic study. In this work, the physical solubility of N2O and CO2 in DMSO was measured in a static equilibrium cell at temperatures of (293.15–333.15) K. Solubility of N2O in BAE and the BAE/DMSO binary blends with 22.6, 34.9, and 61.8 mass % BAE was also determined. The effect of the water content on N2O solubility in the water-lean ternary blends with 61.8 mass % BAE was also discussed. The ratios of solubility of CO2 to N2O in polar solvents (i.e., DMSO and water) were found to be very close at temperatures of 323–333 K. Experimental solubility data and the ones calculated from the recommended correlation models match well with each other, with average absolute relative deviations within 0.9%.