At these temperatures, the aluminium is dissolved as sodium aluminate (the Bayer process). The aluminium compounds in the bauxite may be present as gibbsite(Al(OH)3), boehmite(AlOOH) or diaspore(AlOOH); the different forms of the aluminium component will dictate the extraction conditions. The undissolved waste, bauxite tailings, after the aluminium compounds are extracted contains iron oxides, silica, calcia, titania and some un-reacted alumina.
At these temperatures, aluminum is dissolved in sodium aluminate (the Bayer process). Bauxite's aluminum compounds, including gibbsite, boehmite, and diaspore, influence the extraction conditions. The remaining waste after aluminum extraction contains iron oxides, silica, calcium oxide, titanium dioxide, and some unreacted alumina.