Solid–liquid phase equilibrium study of n-octadecane + lauryl alcohol binary mixtures

Differential scanning calorimetry (DSC) is used to investigate the thermal properties of n-octadecane and lauryl alcohol and their binary system. The experimental results show that the phase diagram of the n-octadecane + lauryl alcohol binary system presents a eutectic behavior for the solid–liquid equilibrium line, and the corresponding mole fraction of n-octadecane in eutectic point is 0.257. The eutectic melting temperature (TE) is 292 K, and the latent heat of melting of eutectic mixture (△fusHE) is 245 J · g−1. Furthermore, the activity coefficients of components in mixtures of n-octadecane + lauryl alcohol have been correlated by the Wilson, NRTL and UNIQUAC models, respectively. The best correlation of the solid–liquid equilibrium data has been obtained by the NRTL equation, in which the average root-mean-square deviation of temperature is 0.15 K.

► The phase diagram of the n-octadecane + lauryl alcohol binary system was determined.
► SLE data were correlated with Wilson, NRTL and UNIQUAC models.
► Superior correlation was achieved with NRTL model.