Determination and thermodynamic modeling of solid–liquid phase equilibrium for the 2,4,6-trimethylphenol and 2,5-dimethylphenol binary system

The solid–liquid phase equilibrium for binary system of 2,4,6-trimethylphenol (TMP) and 2,5-dimethylphenol (DMP) was built by differential scanning calorimeter under atmospheric pressure (101.3 kPa). Two thermodynamic models of Wilson and NRTL were employed to correlate and calculate the experimental data for the system. The mean-root-square error values are 0.1924 and 0.2204. The residual sums of square values are 0.4810 and 0.6315, respectively. Values \( R^{2} \) are all larger than 0.9995. The pure TMP, pure DMP and the mixture of them were confirmed by gas chromatography, Raman spectrometer and X-ray diffraction before and after the determination. In addition, the specific heat (Cp) of solid TMP and DMP between 285.15 and 335.15 K and liquid TMP and DMP between 353.15 and 403.15 K were determined at atmospheric pressure.