Abstract

In this work, we calculated (thermal expansion coefficients),  (excess thermal expansion coefficients) and (isothermal coefficient of pressure excess molar enthalpy) for the binary and ternary mixtures of {1-butanol + hexylamine + n-heptane} from experimental densities (Djordjevic et al., 2010) at (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15) K. The trends of and for the binary mixture 1-butanol + hexylamine are S-shaped dependence on composition, and for the binary mixture 1-butanol + n-heptane the trends of and  are positive and negative, respectively over the mole fraction rage. For the binary mixture of hexylamine + n-heptane, the trends of andare negative and S-shaped, respectively. The values of andof binary mixtures were correlated as a function of the mole fraction by using the Redlich–Kister equation and the ternary mixture was fitted by using the Cibulka equation. By using Flory theory, we calculated the values of  and at different temperature; the results show a good agreement between Flory theory and experimental data.

Key words: Thermal expansion coefficients, excess thermal expansion coefficients, isothermal coefficient of pressure excess molar enthalpy, Flory.