COPPER REMOVAL FROM AERATED SOLUTION CONTAINING VARIOUS METAL-IONS USING AN UNDIVIDED ROTATING CYLINDER ELECTRODE REACTOR

Potentiostatic control of a rotating cylinder electrode reactor enable d copper retrieval from a solution containing multiple metallic ions. The treated solution (pH 4 sulphuric acid) was obtained from a mine ta iling. A batch process was used in laboratory experiments to simulate possible industrial treatments. Oxygen reduction was the major parasit ic reaction at the cylinder cathode since the reactor was not separate d, allowing the gas produced at the anode to dissolve in the electroly te. A higher current therefore generated an increase in oxygen product ion and an increase in dissolved oxygen concentration. Since the oxyge n reduction proceeded under diffusion control, the oxygen reduction cu rrent efficiency also increased. Reduction of ferric ions to a ferrous state and arsenic deposition were other less important side reactions decreasing current efficiency. Polarization experiments were conducte d using a rotating disk electrode to study the reactions encountered a t the cylinder cathode.