EXCESS-ENTHALPIES FOR THE TERNARY MIXTURES PHENOL-1-HEXANOL-N-HEPTANEAND PHENOL-CYCLOHEXANOL-N-HEPTANE, AND THEIR CONSTITUENT BINARIES AT 318.15 K

Excess molar enthalpies H-E as a function of composition for the two t ernary systems, phenol-1-hexanol-n-heptane and phenol-cyclohexanol-n-h eptane, and five constituent binaries have been measured with a Calvet -type microcalorimeter at 318.15 K. All the excess enthalpies of binar y systems containing n-heptane are positive, including those for a par tially miscible system, phenol-n-heptane. The H-E values of phenol-alc ohol systems are negative. The results have been used to predict terna ry H-E data by the UNIFAC model and a version of this, the UNIFAC(3Q), both with enthalpy-fitted interaction parameters. It was found that t he models could only qualitatively predict the ternary H-E values.