VOLUMETRIC PROPERTIES OF SOLUTIONS OF DIMETHYLSULFONE IN ETHANOL-WATER MIXTURE AT TEMPERATURES RANGE OF 298.15-323.15 K

Abstract

This paper studies volumetric properties of ternary dimethylsulfone-ethanol-water systems. The biomedical and environmental significance for the fundamental investigations of aqueous solution of dimethylsulfone and influences of third component on volumetric behavior of this system arises from several reasons. In the global sulfur cycle dimethylsulfide is converted to dimethylsulfone leading to an annual atmospheric production of some million tones of dimethylsulfone, much of which would be deposited in rain and snow. In addition, dimethylsulfone has been extensively studied from a medical point of view. It was established that dimethylsulfone is contained in small amounts in human blood and urine. Also of interest is that methionine is transformed into dimethylsulfone in living organisms. In this work densities of solution of dimethylsulfone in ethanol-water mixtures with various compositions have been measured over available concentration range. As it is evident from experimental data, the increase in a temperature leads to the reduction of density. The apparent and partial molar volumes of solutions were determined over the 298.15–323.15K temperature range. As it follows from these data, the apparent molar volumes increase with increasing of temperature. The influence of ethanol on the volumetric behavior has been taken into account by changing the apparent molar volume compared with the apparent molar volume of the binary aqueous solutions of DMSO2. It is found also the effect of the amount of ethanol on the volumetric properties of these solutions. It is interesting that the effect of ethanol on the values of apparent molar volumes does not change monotone with increasing in quantity of ethanol in ethanol-water mixture. In dimethylsulfone+(ethanol-water) solutions the partial molar volume of dimethylsulfone increases when quantity of ethanol in ethanol-water mixture more than 0.5 molar fraction. The observed phenomena are explained by the presence of competition of intermolecular interactions. In the DMSO2-ethanol-water system the strongest interaction between ethanol and water molecules leads to the increase in partial molar volumes for DMSO2.For citation:Ghazoyan H.H., Markaryan S.A. Volumetric properties of solutions of dimethylsulfone in ethanol-water mixture at tempe-ratures range of 298.15-323.15 K. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 7. P. 27-33.