Density and Isobaric Thermal Expansion of the Liquid-Phase Binary Glycerol + Dimethyl Sulfoxide Mixture at Temperatures from 278.15 to 333.15 K and Ambient Pressure

Abstract

The densities of the liquid-phase binary {glycerol (1) + dimethyl sulfoxide (2)} mixture were measured using a vibration densimeter over the entire range of compositions in the temperature range from 278.15 to 333.15 K at atmospheric pressure. At temperatures below the DMSO freezing point, the measurements were carried out over a limited range of compositions. The excess molar volumes, molar isobaric temperature expansions of the mixture, and apparent and partial molar volumes of glycerol (GL) and dimethyl sulfoxide (DMSO), including their limiting values, were calculated. A comparison of the obtained results to the literature data was made. The excess molar volumes were described by the Redlich–Kister equation. The formation of the glycerol + dimethyl sulfoxide mixture was shown to be accompanied by a decrease in volume at all of the temperatures, and as the temperature became higher, the deviation from ideality increased. The limiting partial molar volumes of GL and DMSO were less than their respective molar volumes. The temperature coefficients of the limiting molar isobaric thermal expansion of both glycerol and dimethyl sulfoxide had negative values. The results obtained were discussed from the perspective of solute–solvent and solute–solute interactions.