Thermophysical Properties of Binary and Ternary Mixtures Comprising Methyl Acetate, n-Hexane, and Cyclohexane: Experimental and Modeling Approach

Experimental densities and sound speeds measured at temperatures (288.15, 298.15, 308.15, and 318.15) K under ambient pressure conditions are reported for the first time for the ternary system (methyl acetate + n-hexane + cyclohexane) covering the entire composition range. The corresponding binary subsystems (methyl acetate + n-hexane), (methyl acetate + cyclohexane), and (n-hexane + cyclohexane) have also been studied. The excess molar volumes and excess isentropic compressibilities were calculated from experimental data and correlated using Redlich-Kister and Cibulka equations for binary and ternary systems, respectively. The composition and temperature dependence of these properties provided insights into the nature of molecular interactions and structural effects within the mixtures. The Jouyban-Acree model effectively captured the composition and temperature dependence of densities and sound speeds, and their closely related properties, namely isobaric thermal expansivities and isentropic compressibilities, of the studied binary and ternary mixtures with an optimized set of adjustable parameters. Finally, the ternary excess molar volumes and excess isentropic compressibilities were compared with the predicted values from binary contribution symmetric (Kohler and Muggianu) and asymmetric (Hillert and Toop) models. Kohler symmetric model effectively predicted the excess molar volumes, while the asymmetric Hillert model yielded superior prediction for excess isentropic compressibility, particularly when n-hexane was treated as the asymmetric component.