Homotopy method to predict liquid–liquid equilibria for ternary mixtures of (water + carboxylic acid + organic solvent)

Liquid–liquid equilibrium (LLE) measurements of the solubility (binodal) curves and tie-line end compositions were carried out for the ternary systems (water + acetic acid + dichloromethane), (water + acetic acid + methyl isobutyl ketone), (water + lactic acid + methyl isobutyl ketone) at T = 294.15 K and atmospheric pressure. The reliability of the experimental tie-line data was ascertained by means of the Othmer–Tobias and Hand correlations. For the extraction effectiveness of solvents, the distribution and selectivity curves were plotted. In addition, the interaction parameters for the UNIQUAC and NRTL models were retrieved from the obtained experimental results by means of a combination of the homotopy method and the genetic algorithms.

► LLE data of ternary systems (water–carboxylic acid–solvents) are experimentally studied. ► The homotopy method and the GA are used for the estimation of the interaction parameters of NRTL, UNIQUAC. ► The experimental results are compared with values predicted by NRTL and UNIQUAC.