A Characterization of the Aliphatic/Hydroxyl Interactions using a Group Contribution Model (Disquac)

Abstract

AbstractThe data available in the literature for the molar excess Gibbs energies GE, azeotropes, molar excess enthalpies HE, activity coefficients γi∞, and partial molar excess enthalpies HiE,∞, at infinite dilution, and molar excess heat capacities CpE, of n‐alkan‐1‐ol (1) + n‐alkane (2) mixtures are examined on the basis of the DISQUAC group contribution model. Being available the interaction parameters for systems containing methanol or ethanol, we report the interchange coefficients from propanol to hexadecanol: Cah.1DISand Cah,1QUAC (1 = 1,2 or 3). For the dispersive coefficients: Cah,1DIS increase with the size of the n‐alkan‐1‐ol; Cah,3DIS decrease as far as propanol, and then increase regularly, an opposite behaviour is encountered for Cah,3DIS the quasichemical coefficients: Cah,1.DIS and Cah,3.DIS are constant, and Cah,3CUAC varies in a similar way to the maximum of the HE of the mixtures under study; from decanol, they are constant. The model describes consistently the molar excess functions for the systems investigated, even the CpE and, qualitatively, the temperature dependence of this magnitude. Partial molar excess quantities at infinite dilution are reasonably well represented. Larger differences are obtained for H1E,∞.