Thermodynamic study of the mixtures (butylbenzene + an alkane or + an alkyl ethanoate): Experimental Hm(E) and Vm(E) values

Abstract

This article shows the experimental data of mixing properties for a set of nine binary mixtures formed by an aromatic hydrocarbon, butylbenzene, with several alkanes (C-7 to C-12) and several alkyl ethanoates ( methyl to butyl). The excess enthalpies, H-m(E), were measured at T = 298.15 K for all systems, while the excess volumes, V-m(E), were obtained for the same set of systems but at two temperatures of 298.15 and 318.15 K. All systems studied presented endothermic effects with the excess enthalpy increasing regularly as the alkane chain-length increases, however in the mixtures with ethanoates the endothermicity decreases with the increase of the ester molecular weight. In this case V-m(E) are positive for all systems except for those mixtures containing heptane or octane, which present V-m(E) < 0. In both sets of mixtures the temperature effect on V-m(E) is analysed. All experimental values are correlated with a suitable equation. Lastly, the UNIFAC model is applied to all the mixtures to estimate the H-m(E) considering two versions, being necessary to recalculate the interaction parameters corresponding to methyl/aromatic and carboxylate/ aromatic in the version of Dang and Tassios (Ind. Eng. Chem. Des. Dev., 25, 22, 1986). The estimation for the elected mixtures is acceptable.