modeling of liquid–liquid equilibria of aqueous alcohol + salt systems using amodified nrtl

the modified nrtl (m-nrtl) model is used to represent the excess gibbs free energy of aqueous (alcohol + electrolyte) solutions. in this work, the m-nrtl model previously developed for representation of vapor-liquid equilibria for (polymer + salt + water) systems has been extended to represent liquid-liquid equilibria of (alcohol + salt + water) systems. the proposed extension is a modified of the extended nrtl model. the model provides a thermodynamic framework for both correlating and predicting the phase equilibrium of complex systems containing both electrolytes and alcohol. the utility of the model is demonstrated with successful representation of (liquid + liquid) equilibrium of several (alcohol + salt + h2o) systems at different temperatures. the liquid–liquid equilibria of the ternary systems involved and the mean activity coefficients of the salt + water systems were used simultaneously to obtain the adjustable parameters. for the several aqueous systems containing an alcohol and a salt the performance of this m-nrtl model was examined at the correlation of lle data. in addition, the results of suggestion model were compared with those obtained using the setschenow-type equation, extended wilson (e-wilson) and extended nrtl (e-nrtl) models.