Excess molar enthalpies of mixing of 1-butanol with aromatic hydrocarbons at 308.15 K

Abstract

Molar excess enthalpies, <em>H^E, </em>of mixing data for 1-butanol with benzene, toluene and <em>o-</em> <em>m- </em>and <em>p</em>-xylenes at 308.15 K over the entire range of composition have been reported. <em>H^E </em>values for all the present binary mixtures are positive and <em>H^E </em>versus mole fraction curves are slightly skewed towards the low mole fraction of 1-butanol, x₁ having <em>H^E </em>(max) at x₁=0.3S. Qualitatively, the data show the dissociation of self associated 1-butanol molecules through hydrogen bonding with the addition of aromatic hydrocarbons. Further there are electron- donor acceptor interaction between the p - electrons of aromatic ring and the hydroxyl hydrogen. of 1- butanol. Quantitatively, the data have been analysed in terms of the Mecke-Kempter type association model with a Flory contribution term by estimating association parameters like standard enthalpy, entropy and volume of H-bond formation.