Density and refractive index at 298.15 K and vapor-liquid equilibria at 101.3 kPa for binary mixtures of ethanol plus N-methylpiperazine

Densities and refractive indices at 298.15 K, and isobaric vapor-liquid equilibrium (VLE) data at 101.3 kPa are reported for the binary mixtures of ethanol + N-methylpiperazine. Excess molar volumes and refractive index deviations are calculated from the measurement results. Negative values for excess molar volumes are observed over the whole composition range, whereas refractive indices exhibit positive deviations from linear additive values. The VLE data are correlated by the UNIQUAC liquid-phase activity coefficient model with satisfactory results. This binary system has no azeotrope.