Alumina Refining Process

The industrial method, predominantly the Bayer process, used to chemically extract aluminium hydroxide from bauxite and convert it into alumina. The process involves digestion of bauxite in hot caustic soda solution, separation of the resulting sodium aluminate liquor from red mud residue, precipitation of aluminium hydroxide from the liquor, and calcination of hydrate to produce anhydrous alumina for use in aluminium smelting.