Extracting Alumina

The process of extracting a metal from its oxide is known as 'smelting'. Most smelting processes involve direct reduction of the ore by carbon to metal and carbon dioxide. The production of primary aluminium is a good example of such a process.

Bauxite - a rock composed of hydrated aluminium oxides - is the main ore of aluminium oxide (Al2O3), commonly known as 'alumina', which is used to make aluminium (Al). Mined bauxite is refined into alumina, which is then converted into metallic aluminium via an electrolytic process. Once aluminium is formed, the hot, molten metal is alloyed with other metals to make a range of primary aluminium products with different properties and suitable for processing in various ways to make end-user products.

It takes about 2 tonnes of bauxite to produce 1 tonne of alumina; and approximately 2 tonnes of alumina to produce 1 tonne of aluminium.