Isothermal vapour pressures and thermodynamic excess properties of 3,5- and 2,6-dimethylpyridine with cyclohexane. Measurements and prediction

The vapour pressures of liquid mixtures 3,5- and 2,6-dimethylpyridine (or lutidines) with cyclohexane were measured by a static method in the range of 283.15–353.15 K. The pure components vapour pressures data and those of corresponding mixtures were correlated using Antoine type equation. Data reduction by Barker's method provides correlation for excess molar Gibbs energy GE.The excess molar enthalpies HE of binary liquid mixtures of 3,5- and 2,6-dimethylpyridine with cyclohexane were measured at 303.15 K using a Calvet type microcalorimeter, C80 Setaram.The experimental results, along with our previous data of GE and HE[1] and [2] are used for estimating interaction parameters in DISQUAC, an extended quasi-chemical group contribution model [3].