Density, Viscosity, and Excess Thermodynamic Properties of Aqueous Ethylene Glycol in Methanol, Ethanol, and 1-Propanol at 308.15 K

The densities, ρ, and dynamic viscosities, η, of 0.3 and 0.9 m aqueous ethylene glycol solutions containing methanol, ethanol, and 1-propanol were measured over the entire composition range at 308.15 K.The density decreased systematically with increasing mole fraction of the alcohols, whereas the viscosity exhibited a pronounced maximum followed by a decrease at higher alcohol concentrations.From the experimental density and viscosity data, excess molar volume, ( E V m ) , viscosity deviation, Δη, excess enthalpy, H E (H E ), and excess Gibbs free energy of activation of viscous flow, ΔG *E , were evaluated.The ( E V m ) values were negative, while Δη, H E , and ΔG *E were positive over the investigated composition range.The negative E V m ) values indicate contraction on mixing and can arise from a combination of specific unlike-molecule interactions and efficient molecular packing.The positive viscosity deviations and excess enthalpies suggest that disruption of the self-associated structures of the component liquids is an important contribution to the mixing behaviour.The excess properties were correlated using the Redlich-Kister polynomial, and the corresponding standard deviations were determined.Experimental viscosities were also compared with values calculated using the Grunberg-Nissan, Hind et Density, Viscosity … M. Kondaiah and K. Sreekanth.