The liquid–liquid equilibria of systems composed of rice bran oil, free fatty acids, ethanol and water were
investigated at temperatures ranging from 10 to 60 C. The results of the present study indicated that the
mutual solubility of the compounds decreased with an increase in the water content of the solvent and a
decrease in the temperature of the solution. The experimental data set was correlated by applying the
UNIQUAC model. The average variance between the experimental and calculated compositions was
0.35%, indicating that the model can accurately predict behavior of the compounds at different temperatures
and degrees of hydration. The adjustment of interaction parameters enables both the simulation of
liquid–liquid extractors for deacidification of vegetable oil and the prediction of phase compositions for
the oil and alcohol-rich phases that are generated during cooling of the stream exiting the extractor
(when using ethanol as the solvent).