Densities, viscosities and ultrasonic velocities were measured for the two ternary liquid mixtures containing morpholine (1) + 1,4-dioxane (2) + nitrobenzene (3) or + toluene (3) at 308.15 K over the entire range of mole fractions. Thermodynamic parameters, such as excess volume (V E), deviations in adiabatic compressibility (ΔK S), free length (ΔL F), isothermal compressibility (Δβ T), free volume (ΔV F) and viscosity (Δη) were calculated and applied to the Redlich−Kister polynomial equation to determine the appropriate coefficients. The deviations of the ternary liquid mixtures from their ideal behaviour were determined from the measured and calculated thermodynamic properties. In addition, an insight into the molecular structure and possible interactions for the investigated mixtures was attempted.

Thermodynamic properties provide a deep and significant insight of the various interactions taking place multi component liquid mixtures especially in the field of petrochemical and reservoir engineering. The density, viscosity and ultrasonic velocity were measured experimentally for diethylmalonate (DEM) +1,4-dioxane with nitrobenzene (TM-1) and diethylmalonate (DEM) +1,4-dioxane + toluene (TM-2) at the temperature of 308.15K and atmospheric pressure over the entire range of mole fraction. The excess thermodynamic properties such as excess volume (VE), excess adiabatic compressibility (ΔKs), excess viscosity (Δɳ), excess free volume (ΔVF), excess free length (ΔLF), excess isothermal compressibility (ΔβΤ), were calculated from measured values and applied to Redlich - Kister polynomial equation to determine the appropriate coefficients. The excess or deviation properties were found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures. The deviations of the ternary mixtures from its ideal behaviour were determined in order to investigate the molecular interaction between the components of ternary liquid mixtures.

No abstract