Patent ID: 6942810

Claim:
A method for treating a metal-containing liquid, wherein the metal-containing liquid also comprises reducing agents, the method comprising: providing a reaction vessel containing an anode, a cathode, and a hydrogen ion-permeable membrane separating the anode and the cathode; disposing the metal-containing liquid to be treated in the reaction vessel in contact with the anode; disposing a catholyte solution in contact with the cathode; a first placing of the anode and cathode in electrical communication with a power source and driving an electrical current through the anode and the cathode until at least a majority of the reducing agents in the metal-containing liquid are oxidized to create an intermediate liquid and a used catholyte solution; removing the used catholyte solution from contact with the cathode and the intermediate liquid from contact with the anode, optionally from the reaction vessel separately to a first and a second reservoir respectively; disposing the intermediate liquid in contact with the cathode; disposing an anolyte solution in contact with the anode; and a second placing of the anode and cathode in electrical communication with a power source and driving an electrical current through the anode and the cathode until a majority of the metal ions in the intermediate liquid are plated onto the cathode to provide a treated solution.