Electrolytic refining:
It is type of cell unit in which a thick rod of impure metal is made to act as anode whereas the thin sheet of pure metal is used as cathode. They are dipped in a suitable acidic solution of soluble salt of the same metal which is used in the form of electrolyte. On passing electricity, the metal from the anode goes into solution as ions due to oxidation while pure metal gets deposited at the cathode by accepting electrons. Refining of copper and zinc etc. is done by electro refining method.
