Isothermal Vapor−Liquid Equilibria and Excess Enthalpy Data for the Binary System (Butyric Acid + Toluene)

The vapor pressures of (butyric acid + toluene) and of the pure components were measured by means of a static device at temperatures between (273 and 363) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions were calculated for several constant temperatures and fitted to a fourth-order Redlich−Kister equation. The system shows positive deviation from ideality. Additionally, molar excess enthalpies, HE, for the binary (butyric acid + toluene) system have been measured at 323.15 K using an isothermal flow calorimeter.