Liquid-liquid equilibrium study for ternary system of (water + acetic acid + 2-heptanol)

Abstract

The efficient extraction of acetic acid from dilute aqueous solution is of both research and industrial value. In order to search for acetic acid extractants, the liquid–liquid equilibrium of the ternary system (water + acetic acid + 2-heptanol) was studied at temperatures ranging from 303.2 K to 323.2 K. According to experimental results, 2-heptanol showed high extraction capability and low water miscibility. It is also observed that the distribution coefficient and the separation factor are insensitive to temperature, which facilitates the practical operation. The authenticity of phase equilibrium data was validated by Othmer-Tobias equation and Hand equation. Experimental data were also correlated with NRTL and UNIQUAC models, and binary interaction parameters of ternary system were obtained. Both NRTL model and UNIQUAC model showed high agreement with the experimental data, with NRTL model more accurate than UNIQUAC model.