Wikipedia
Bayer process
The Bayer process is the principal industrial means of refining bauxite to produce alumina (aluminium oxide). Bauxite, the most important ore of aluminium, contains only 30–54% aluminium oxide, (alumina), AlO, the rest being a mixture of silica, various iron oxides, and titanium dioxide. The aluminium oxide must be purified before it can be refined to aluminium metal.
Usage examples of "bayer process".
The infamous red mud is heated with limestone (calcium carbonate) and soda to regenerate sodium aluminate, and the solution is fed back into the Bayer process.