In electrolytic reduction graphite electrodes are used which are of same size. in electrolytic refining the anode is made of the impure metal which is to be purified and the cathode is made from that pure metal. ... whereas in electrolytic reduction molten chloride form of the solution is used.

Electrolytic reduction and electrolytic refining are two different processes used in metallurgy. Though they both involve the use of electrolysis for the extraction and purification of metals, there are distinct differences between them. Let's explore each process in detail:

Electrolytic Reduction:
Electrolytic reduction is a process used to extract metals from their ores. It involves the reduction of metal ions (positive ions) at the cathode (negative electrode) during electrolysis. The key points of electrolytic reduction are as follows:

1. Electrolyte: An electrolyte is a solution or molten compound that contains metal ions. It acts as a medium for the flow of electricity during electrolysis.

2. Cathode: The cathode is the negative electrode where reduction takes place. Metal ions gain electrons at the cathode and are reduced to their respective metal atoms.

3. Reduction: During electrolytic reduction, metal ions are reduced by gaining electrons. This results in the deposition of pure metal on the cathode. For example, in the electrolytic reduction of aluminum oxide, aluminum ions (Al3+) gain electrons and are reduced to form aluminum metal (Al).

4. Anode: The anode is the positive electrode where oxidation occurs. It releases electrons into the electrolyte, maintaining the overall electrical balance during electrolysis.

5. Oxidation: At the anode, a reaction called oxidation takes place. Here, negatively charged ions or atoms lose electrons and are oxidized to form positive ions. In the case of aluminum extraction, oxygen ions (O2-) are oxidized to form oxygen gas (O2).

Electrolytic Refining:
Electrolytic refining is a process used to purify metals that have already been extracted from their ores. It involves the purification of impure metals through electrolysis. The key points of electrolytic refining are as follows:

1. Anode: In electrolytic refining, the impure metal is used as the anode. The impurities present in the metal are oxidized and dissolve into the electrolyte as ions.

2. Cathode: The cathode is a pure metal sheet or rod, often made of the same metal as the one being refined. The pure metal is deposited on the cathode during electrolysis.

3. Purification: As the impurities dissolve into the electrolyte, they are removed from the anode. Meanwhile, the pure metal ions from the electrolyte are reduced at the cathode, resulting in the deposition of pure metal. This process helps in the removal of impurities such as copper, zinc, and lead from the metal being refined.

4. Electrolyte: The electrolyte used in electrolytic refining depends on the metal being purified. It may be a solution of a suitable compound containing the metal ions.

In summary, electrolytic reduction is used to extract metals from their ores, while electrolytic refining is employed to purify already extracted metals. Electrolytic reduction focuses on the reduction of metal ions at the cathode, while electrolytic refining aims to remove impurities from the metal by dissolving them into the electrolyte. Both processes utilize the principles of electrolysis but serve different purposes in the