This study focuses on the removal of metallic impurities such as Fe(II), Fe(III), and Cr(III) from spent plating solutions via electrolytic separation. A two-chamber electrolytic cell separated by a ceramic membrane was used. The choice of the catholyte affected the removal rate of iron. As compared to chromic acid, sodium monophosphate was found to provide the maximum removal rates for iron (5.89 mM h(-1)). The main modes of mass transfer across the ceramic membrane were diffusion driven by concentration gradient and cation migration. Subsequent removal of the impurity from the cathode compartment was achieved via electrodeposition and precipitation as sludge. The iron removal increased 69% when the applied potential was increased from 5 to 7.5 V, while an increase in temperature from 45 to 55degreesC resulted in a 33% decrease in impurity removal. In addition, regeneration of Cr(VI) occurred simultaneously due to the anodic oxidation of Cr(III). The rate of regeneration was found to depend on the applied potential and the concentration of the Cr(111) species in the anode chamber. A mathematical model describing the process was developed and validated. Modeling results indicate that a greater iron removal could be obtained if the impurities transported to the catholyte are deposited or precipitated at a faster rate. The estimated mobilities, diffusivities are in good agreement with those reported in the literature. (C) 2005 The Electrochemical Society. All rights reserved.