Extraction of aluminium

• The main ore of aluminum is bauxite – high m.p.
• Aluminum (III) oxide (alumina) is dissolved in molten cryolite – this mixture has a lower m.p. (industrially preferred)

  
• During electrolysis aluminum is produced at the carbon cathode and oxygen at the carbon anode.
• Due to the high temp. the oxygen reacts with the carbon in the graphite anode to form CO2 and so anode has to be periodically replaced