Thermodynamic properties of (a propyl ester + ann-alkane). XII

Abstract

Excess molar enthalpies HmE and excess molar volumes VmE were determined at the temperature 298.15 K for 21 binary mixtures of three propyl esters (ethanoate, propanoate, and butanoate) and seven odd n-alkanes(pentaneto heptadecane). All the mixtures exhibited endothermic enthalpies which decreased quasi-exponentially with the ester chain length in the same proportion as their dipole effects. The variations of the excess molar volumes for these mixtures followed a similar decreasing trend, with contractions observed in the systems consisting of high molar mass esters and lowest n-alkanes. These effects have been interpreted on the basis of molecular interactions. The UNIFAC, DISQUAC, and Nitta-Chao models were used to estimate the thermodynamic properties considered, and yielded acceptable results. © 1999 Academic Press.