Modeling of Liquid-Liquid Equilibrium Data and Estimation of New Binary Interaction Parameters for NRTL Model for the Quaternary System Water/ Ethanol/1-Butanol / KCL at 298.15K

Abstract

The present study concerns experimental measurements of the salting-out effect on liquid-liquid phase equilibrium (LLE) of partially miscible systems such as water/ ethanol/1- butanol /Potassium chloride at 298.15K. The salt KCl was used at different mass percentages of 5, 10 and 15. The binodal and tie line data results were determined by the cloud point method. The addition of the salt showed to be effective in altering the LLE of water/ ethanol/1- butanol system in favor of the solvent extraction of ethanol from the aqueous solution particularly at high salt concentrations. The experimental data were correlated considering the modified version of the NRTL model for the activity coefficient, with the estimation of new binary interaction parameters corresponding to salt-solvent and solvent-solvent pairs. The deviations between experimental and calculated compositions in both phases for the ternary system using these new interaction parameters showed the ability of NRTL to determine liquid-liquid equilibrium data of the studied system in the presence of the salts.