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How Is Aluminium Extracted From Bauxite Ore?

Did you know that aluminium as we know it is not found like this naturally? Even though this handy material is found in over 250 different mineral compounds, it has to be extracted from bauxite, an ore that is mined worldwide. The process to extract the aluminium from its ore is a seemingly complex and time consuming one, and it goes as follows:

Bauxite Mining
The first step in the process is to mine the bauxite from the earth, mostly from underground deposits (the largest ones can be found in Southern Europe and Hungary). The bauxite is blasted loose and washed to remove any excess clay.

Bayer Process
The second step is known as the Bayer process, which involves a combination of a chemical extraction and a mechanical separation to extract alumina (the base from of aluminium) from the bauxite.

• In the first step of the process, the alumina is released from the bauxite when it is crushed and dissolved in sodium hydroxide. The resulting solution travels through a number of filters and separators to remove insoluble particles (leaving a liquefied sodium aluminate).
• In the second step, the alumina is recovered from this solution when it crystallizes in a precipitation tank. The alumina settles on the bottom, is dried and ground into a find white powder that can be further refined into metallic aluminium.

As you can see, the process used to extract aluminium from the bauxite ore it originates in is fairly complex and requires a number of different machines in order to be completed. Whilst the biggest aluminium manufacturing plants are located in Europe, they do exist here in Australia, just not on the same large scale due to our smaller deposits.