The process shown in the diagram is electro-refining.

Electrolytic refining of silver can be done, where in the apparatus anode should be impure silver and cathode should be a thin strip of pure silver. The electrolyte used for the process is the Silver Nitrate solution.

The anode and cathode formed by assembling the apparatus should be connected to positive and negative terminals of a battery respectively.

Diagram:

When electric current is passed through the electrolyte, the impure silver from the anode is dissolve in the electrolyte and an equal amount of pure silver from the electrolyte is deposited on the cathode.

The soluble impurities go into the solution whereas the insoluble impurities settle down at the bottom of the anode which is known as anode mud.

In this way, silver can be refined through electro-refining.