Solubility of n-alkanols (C16, C18, C20) in binary solvent mixtures

The solubilities of C16, C18, C20 n-alkanols (1-hexadecanol, 1-octadecanol, 1-eicosanol) in 12 binary solvents consisting of cyclohexane and heptane or 2-propanol have been measured by a dynamic method from 286 K to melting point. Cyclohexane + 2-propanol mixed solvent systems were found to exhibit the synergetic effect of solubility. The results of these measurements have been compared with those predicted by means of six correlation equations that describe the Gibbs excess free energy of mixing GE: the equations of Wilson, UNIQUAC, UNIQUAC associated-solution model, as well as the simple and two modified NRTL equations. The best predicted results and correlation were obtained with UNIQUAC associated-solution model.