Liquid–liquid equilibrium for the ternary system of 1-butanol + 3-methyl-1-butanol + water at different temperatures

Liquid–liquid equilibrium (LLE) data for the ternary system 1-butanol + 3-methyl-1-butanol + water were measured at T = 298.15, 333.15 and 368.15 K under atmospheric pressure, respectively, in this article. The reliability of the experimental data was checked by Othmer–Tobias, Bachman and Hand correlations. Moreover, the NRTL and UNIQUAC activity coefficient models were applied to correlate the measured data and both of them gave a root-mean-square deviation (rmsd) of less than 0.0057. The results showed that both models were suitable for the determination of LLE data of the studied system at the investigated temperatures.

► LLE data for the system 1-butanol + 3-methyl-1-butanol + water have been measured.
► The effect of temperature on LLE diagrams for the ternary system has been detected.
► The NRTL and UNIQUAC models have been used to correlate the experimental data.
► A good agreement has been observed between the calculated and the experimental data.
► The NRTL and UNIQUAC interaction parameters were calculated.