Study of the thermophysical properties for aqueous alkanediols binary mixtures

• Published in: Journal of molecular liquids Vol. 335; p. 116150
• Main Authors: Dragoescu, Dana, Sirbu, Florinela, Almásy, László
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2021
• Subjects: 1,2-Hexanediol; 1,5-Pentanediol; Microheterogeneity; Molecular interactions; Prigogine-Flory-Patterson (PFP) theory; Thermodynamic properties; Thermodynamic properties; 1,5-Pentanediol; Molecular interactions; Prigogine-Flory-Patterson (PFP) theory; 1,2-Hexanediol; Microheterogeneity
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2021.116150

Partial molar volumes V¯2 values of water in the 1,2-Hexanediol/1,5-Pentanediol (1) + water (2) binary mixtures versus molar fraction x1, at 298.15 K. [Display omitted] •Physico-chemical properties data of alkanediols (1) + water binary (2) mixtures were reported.•The densities and refractive indices data were used to calculate the derived volumetric properties.•The speeds of sound data were used to calculate the excess isentropic and excess molar isentropic compressibilities.•The excess properties were correlated with the Redlich-Kister equation and with the Prigogine-Flory-Patterson model.•The results are discussed in terms of structural effects between components. The thermophysical properties data as densities, speeds of sound, and refractive indices for aqueous binary mixtures of 1,2-hexanediol and 1,5-pentanediol, have been measured at several temperatures in the range of (298.15–318.15) K, atmospheric pressure, and in the whole domain (0 to 1) of diol molar fractions. From the obtained experimental values, the related excess and deviation quantities, namely the excess molar volumes, the partial/apparent molar volumes, the isentropic compressibilities, the excess isentropic compressibilities and the deviation in refractive indices were calculated. The excess thermodynamic properties were correlated with the Redlich-Kister polynomial equation. The experimental excess molar volumes values have been also used to test the applicability of the Prigogine-Flory-Patterson theory and the results were analyzed in terms of molecular interactions between the components of the mixture. Discussions concerning the experimental and calculated results in relation to the molecular interactions and structural effects between components of mixtures are presented. In the dilute range, at (0 to 0.3) diol mole fractions, the characteristic behavior of the excess and partial molar quantities was related to the structural changes in the mixtures as observed by neutron scattering.