Electrochemical cell and process for reducing the amount of organic contaminants in metal plating baths

A process for electrochemically reducing the amount of an organic contaminant in an aqueous metal plating solution containing such contaminant, comprising

• (a) providing an electrochemical cell, the electrochemical cell comprising
• an anode compartment,
• an anode located in the anode compartment,
• an anolyte comprising an aqueous acidic liquid metal plating solution
• containing an organic contaminant and a metal ion,
• a first pump for circulating the anolyte through the anode compartment,
• a cathode compartment,
• a cathode located in the cathode compartment,
• a catholyte,
• a second pump for circulating the catholyte through the cathode compartment,
• a separator between the anode and the cathode, comprising an ionically conducting solid polymer membrane material, and
• a power supply for supplying dc current to the cell,
• wherein the anode includes active material which is stable at acid pH and at high electrical potential, and which selectively breaks down organic compounds by electrochemical oxidation, and wherein the separator minimizes the loss of metal ions from the anolyte,
• (b) activating the dc power supply to provide electrical current to the cell,
• (c) activating the first pump to circulate the anolyte through the anode compartment to expose the aqueous solution to the anode to selectively break down the organic contaminant by electrochemical oxidation,
• (d) activating the second pump to circulate the catholyte through the cathode compartment, and
• (e) removing the aqueous metal plating solution having a reduced amount organic contaminant from the anode compartment.