Measurement and correlation of liquid–liquid equilibria for water + ethanol + mixed solvents (dichloromethane or chloroform + diethyl ether) at T = 293.15 K

Abstract

Liquid–liquid equilibrium (LLE) data for the quaternary systems (water + ethanol + dichloromethane (DCM) or chloroform (CHCl3) + diethyl ether (DEE)) were experimentally investigated at 293.15 K. The thermodynamic consistency of the data was performed using the Othmer–Tobias and Hand plots. The experimental tie-line data were correlated using the non-random, two-liquid (NRTL) model. As a result, the comparison of the extracting capabilities of the mixed solvents with respect to the distribution coefficients and separation factors showed that the (50% DCM +50% DEE) system had a higher separation factor for the (water + ethanol + DCM + DEE) system. On the other hand, the (50% CHCl3 +50% DEE) system had a higher separation factor for the (water + ethanol + CHCl3 + DEE) system. The last solvent (50% CHCl3 +50% DEE) was found to be the best solvent, with a positive synergistic effect on DEE, high separation factor, and very low solubility in water.