Bayer Process

The dominant industrial process for producing alumina from bauxite, developed by Karl Bayer in 1887. The process involves four main stages: digestion (dissolving aluminium hydroxide minerals in hot caustic soda), clarification (separating insoluble bauxite residue), precipitation (crystallising aluminium hydroxide from solution), and calcination (heating to convert hydroxide to anhydrous alumina). The Bayer process accounts for over 95% of global alumina production and is fundamental to the aluminium industry supply chain.