Deacidification of vegetable oils can be easily performed by liquid-liquid extraction using appropriate solvents like ethanol. This paper reports experimental data for systems containing palm oil + palmitic/oleic acid + ethanol + water at 318.2 K and different water contents. The addition of water to the solvent reduces the loss of neutral oil in the alcoholic phase and improves the solvent selectivity. The experimental data were correlated by the NRTL and UNIQUAC models. For systems with palmitic acid, the global deviations between experimental and calculated concentrations were 0.75% for the NRTL model and 0.61% for the UNIQUAC equation. For systems with oleic acid, the corresponding values were 1.05% and 0.84%. The adjusted interaction parameters were used to predict the equilibrium of bleached palm oil + aqueous ethanol at 318.2 K, with deviation between calculated and experimental mass percentages not higher than 1.60%. (C) 2004 Elsevier B.V. All rights reserved.