• Reduction: The process can be done by either heating the metal oxide or chemically reducing the metal oxide using chemical reducing agents such as carbon, aluminium, sodium, or calcium.

• Electrolytic reduction: Electrolytic reduction is the process used to extract oxides (or chlorides) of highly reactive metals like sodium, magnesium, aluminium, and cal­cium. Molten oxides (or chlorides) are electrolyzed. The cathode acts as a powerful reducing agent by supplying electrons to reduce the metal ions into metal. For example: Fused alumina (molten aluminium oxide) is electolysed in a carbon lined iron box. The box itself is the cathode. The aluminium ions are reduced by the cathode.

Fig. 14.12 Magnetic separation