Journal of Applied Electrochemistry, Vol.30, No.1, 61-70, 2000
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 using a flow-through cell with a reticulated vitreous carbon cathode is proposed. The operational conditions for the reactor were optimized as a function of the electrolyte pH, the cathode porosity and the solution flow rate. Both a synthetic solution and a real effluent from an industrial electroplating plant were processed until zinc concentration dropped from 50 to 0.1 mg dm(-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 have shown that the current density decreases from the outer surface to the centre of the RVC cathode.
Keywords:RETICULATED VITREOUS CARBON;MASS-TRANSFER;AQUEOUS-SOLUTIONS;FLOW;ZINC;CELL;ELECTROCRYSTALLIZATION;DEPOSITION;BEHAVIOR;REACTOR