PRESSURE EFFECTS ON THE THERMODYNAMIC PROPERTIES OF (N-HEXANE PLUS 1-HEXANOL) BINARY-MIXTURES

On the basis of pressure-scanning measurements of isobaric thermal exp ansivities, alpha(p)(p,T), of n-hexane, 1-hexanol and their binary mix tures at 0.1088, 0.2735, 0.4965, 0.6034, and 0.7453 hexanol molar frac tions, and of isotherms of molar volumes at reference temperatures, th e pressure derivatives of excess thermodynamic functions have been der ived over the pressure range up to 400 MPa and at temperatures from 30 3 to 503 K. The obtained results presented in the form of isobars-isop leths clearly demonstrate the shifting, from positive to negative, of the pressure effects on thermodynamic functions when composition, temp erature or pressure varies. The observed phenomena are discussed in te rms of association equilibria in this system. (C) 1997 Elsevier Scienc e B.V.