LLE (liquid-liquid equilibria) data have been determined for the n-butyl alcohol-water-butyl acetate ternary system and the related binary systems at20℃

30℃ and 40℃. The experimentally determined LLE data for the n-butyl alcohol-water binary system have been found to be in satisfactory agreement with available literature data. The correlation and prediction of the LLE data have been done by using NRTL and UNIQUAC models. The model parameters of binary systems have been identified with a thermodynamic criterion. In the correlation of ternary LLE data

two objective functions (mole fraction and distribution constant) have been used for purpose of comparison. The effect of weighting in the first objective function has been examined. In predicting the ternary LLE with different sets of parameter values obtained for each of the constitutent binary systems

improved prediction results have been obtained by comparing the results of different combinations of the sets of parameter values and choosing those giving the best results.