Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

Mixtures formed by cyclohexane p 1-alkanol have been investigated in the framework of the Kirkwood-Buff theory of solution. The alcohols considered are 1-pentanol up to 1-decanol. Data for the Kirkwood-Buff integrals, Gij excess or deficit number of molecules around the central ones, Dnij and coefficients of linear solvation, dij are reported. For solutions with a given cyclohexane, the increase in the eCH2 groups of alcohols chain causes a decrease in G12 by the following sequences: 1-decanol greater than 1-nonanol greater than 1-octanol greater than 1-heptanol greater than 1-hexanol greater than 1-pentanol. The comparison of G12 and other calculated parameters for cyclohexane p 1-alkanol mixtures reveals that the interactions between similar molecules are more outstanding and the decrease in the alkyl chain of alcohols leads to the weakening of interactions related to the selfeassociation of 1-alkanol, differences in the free volumes, hydrophobic interactions, and structural changes. These trends are consistent with experimental data on the excess molar volumes.