Electrolysis in industrial process

Anodising of aluminum
Anodising is the process of increasing the thickness of aluminum oxide layer on the surface of aluminum in order to protect the metal underneath. The aluminum that is to be anodised is made the electrode during the electrolysis of sulphuric acid. Recall that oxygen is evolved at the anode during the electrolysis. the oxygen released combines with aluminum and thickens the oxide layer.

Electrolytic purification of copper
The impure copper rod is made the anode. At the anode, the copper ions is oxidized to Cu2+ ions. The Cu2+ ions is attracted to the cathode where is gains 2 electrons to form the copper metal. The electrolyte is copper sulphate solution. Effectively the copper is transferred from the anode to the cathode.