Salt effect on the liquid-liquid equilibrium of (water + diethanolamine + isobutanol/cyclohexanol) systems at T = (298.2 and 308.2) K

In this work, salt effect on the liquid phase equilibrium of (water + diethanolamine + isobutanol) and (water + diethanolamine + cyclohexanol) systems was investigated at T = (298.2 and 308.2) K. The liquid-liquid equilibrium data in the presence of KCl and NaCl salts for various ionic strength of 0.5, 1.0, 1.5, and 2.0 mol·dm− 3 and in absence of these salts were determined. The experimental results were correlated based on the Othmer-Tobias equation, Bachman equation and Pitzer ion-interaction model. Thermodynamic properties such as distribution coefficients and activity coefficients of diethanolamine in water + isobutanol and water + cyclohexanol mixtures were determined. In addition, the separation factor of the chosen solvents were obtained for the investigated systems.