What happens at the anode and cathode during silver electrorefining?

In the process of silver electrorefining, impure silver (often in the form of doré bullion) is cast into anodes and placed into an electrolytic cell containing a silver-copper nitrate electrolyte solution.12

• At the Anode: The impure silver anode dissolves into the electrolyte solution as the electric current is applied. Impurities that do not dissolve, such as gold and platinum-group metals, fall to the bottom of the refining tank as slimes, where they are later recovered.231
• At the Cathode: Pure silver ions from the electrolyte solution are deposited onto the cathode.23

This electrolytic process effectively separates the silver from other metals, typically resulting in a high-purity product of 99.9 percent or higher. The specific arrangement of these electrodes depends on the technique used, such as the vertical configuration in the Moebius system or the horizontal setup in the Thum Balbach system.1