Acoustic and volumetric studies on water + diethylene glycol mixtures in a wide temperature range. Comparison with mixtures of water with tri- and tetraethylene glycol

Abstract

Densities (ρ) and sound velocity (u) were measured in the binary liquid mixture of water and diethylene glycol-water (DEG) over the entire mixture composition range. Density values were recorded in a temperature range of 278.15–333.15K under atmospheric pressure, using a precise sealed vibrating-tube densimeter. Sound speed values were recorded in a range of 288.15–318.15K. The values of molar volume (Vm), adiabatic compressibility coefficient (βs), temperature coefficients of these parameters, excess of compressibility coefficient (βsE), excess molar volume (VmE) and derivatives (∂H/∂p), (∂S/∂p) and (∂Cp/∂p) were determined from the experimental data.The values of molar volume were used to determine the values of partial molar volumes of the mixture components. Changes in the values of physicochemical parameters measured and calculated as functions of composition and temperature were analyzed in the aspect of intermolecular interactions in two-component systems. The results obtained were compared with the results of similar studies of the mixtures of water and tri- and tetraethylene glycols.