Measurements and Analysis of Excess Enthalpies of Ester + n‐Alkane Using the UNIFAC Model

Berichte der Bunsengesellschaft für physikalische Chemie 05/2010; 95(2):128 - 135. DOI: 10.1002/bbpc.19910950205

ABSTRACT We present new experimental data of the excess molar enthalpies at 298.15 K for eighteen different binary mixtures of nine methyl alkanoates (ethanoate to decanoate) with n-heptane and n-undecane. The results show that all the systems are endothermic, hE values increase with the length of the n-alkane and decrease with the length of the methyl ester. The data have been analysed with a version of the UNIFAC model, and the parameters corresponding to the CH2/COOC interaction have been recalculated using a larger base of experimental data. New values for the CH2/COO interaction parameters have been obtained.

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