In this work, the viability study of the removal of zinc and iron from chromium (III) passivating baths is presented. The Emulsion Pertraction Technology (EPT), a liquid-liquid extraction process performed in membrane contactors has been applied. Real passivating baths with the following metal concentrations have been tested: Zn, 7000 mg/L; Fe, 30 mg/L and Cr, 5500 mg/L respectively. After the EPT treatment and at the applied experimental conditions, these concentrations were decreased to 2450 mg/L of Zn and 4 mg/L of Fe, while the chromium concentration was maintained approximately at the initial value. The EPT process allowed the simultaneous recovery of Zn in a concentrated stripping phase. The influence of the pH of the feed phase strongly affected the kinetics of metals removal. A value of pH = 2.5 allowed to attain the required high selectivity values Of alpha(Zn/Cr). (C) 2009 Elsevier B.V. All rights reserved.