Removal of Zn(II) from chloride medium using a porous electrode: current penetration within the cathode

An electrolytic process for the removal of zinc from aqueous solutions usin g a flow-through cell with a reticulated vitreous carbon cathode is propose d. The operational conditions for the reactor were optimized as a function of the electrolyte pH, the cathode porosity and the solution flow rate. Bot h a synthetic solution and a real effluent from an industrial electroplatin g plant were processed until zinc concentration dropped from 50 to 0.1 mg d m(-3) and from 152 to 0.5 mg dm(-3), respectively. After the processing of the real effluent, tomographic images of the cathode were taken in order to investigate the current depth penetration during electrolysis. Results hav e shown that the current density decreases from the outer surface to the ce ntre of the RVC cathode.