Measurement and correlation of liquid–liquid equilibrium data for 2-methyl-1-propanol + 2-propanol + water at several temperatures

Liquid–liquid equilibrium (LLE) tie-line data for 2-methyl-1-propanol + 2-propanol + water were determined experimentally under atmospheric pressure over the temperature range of (298.15–348.15) K, respectively. A type 1 LLE phase diagram for the ternary system studied was got and the influence of temperature on the phase diagrams was reported, too. The Othmer–Tobias and Bachman correlations were applied to check the accuracy of the LLE data reported. Moreover, the experimental data got were regressed with the NRTL (α = 0.2) and UNIQUAC activity coefficient models, meanwhile, the binary interaction parameters between each pair of components in the studied system were obtained. The root-mean-square deviation (RMSD) between the measured and calculated data was less than 0.0032. The results can be used to design and optimize the separation process of aqueous solution containing 2-propanol and 2-methyl-1-propanol.

► LLE tie-line data for 2-methyl-1-propanol + 2-propanol + water have been measured.
► The effect of temperature on phase diagrams for the studied system is detected.
► The NRTL and UNIQUAC models are used to correlate the experimental data given.
► The NRTL and UNIQUAC interaction parameters were obtained.
► A good agreement has been observed between the calculated and experimental data.