Densities, viscosities, excess molar volumes, and refractive indices of acetonitrile and 2-alkanols binary mixtures at different temperatures: Experimental results and application of the Prigogine–Flory–Patterson theory

Abstract

Densities, viscosities, and refractive indices of mixing of acetonitrile with 2-propanol, 2-butanol, 2-pentanol, 2-hexanol and 2-heptanol, have been measured as a function of composition at 293.15, 298.15, 303.15 and 308.15 K and ambient pressure. The excess molar volumes, viscosity and refractive index deviations calculated and fitted to Redlich–Kister polynomials. From the experimental data, partial molar volumes, V ¯ m , i and partial molar volumes at infinite dilution, V m , i o ¯ were also calculated. The latter values are interesting from a theoretical point of view since at infinite dilution the only interactions present are solute solvent interactions. For mixtures of acetonitrile with used 2-alkanols, over the entire range of mole fractions, Δη is negative and both, V m E and Δ n D are positive. The effect of temperature and chain-length of the 2-alkanols on the excess molar volumes, viscosity and refractive index deviations of its mixtures with acetonitrile are discussed in terms of molecular interaction between unlike molecules. The experimental results have been used to test the applicability of the Prigogine–Flory–Patterson (PFP) theory.