A comparative study of thermodynamic properties of binary mixtures containing perfluoroalkanes

Literature data on molar excess enthalpies and molar excess Gibbs energies, liquid-liquid equilibria, activity coefficients at infinite dilution and partial molar enthalpies at infinite dilution of binary mixtures of n-perfluoroalkanes (C-5-C-8)+n-alkanes (C5-C8) and of n-perfluorohexane+linear monoethers of general formula, CH3(CH2)(m)-O-(CH2)(n)-CH3 (m,n=1-4), are treated in the framework of DISQUAC, an extended quasichemical group contribution theory. The systems are characterized by two or three types of contact surfaces: aliphatic (CH3, CH2, CH and C groups), fluorine (F group) and oxygen (O group). Using a limited number of adjusted contact interchange energies parameters, structure dependent, the model provides a fairly consistent description of the thermodynamic properties as a function of concentration. The model may serve to predict missing data.