Why is it important to recycle aluminium?
To recover bauxite (the main aluminium ore) from the earth is a cheap operation as it is of fairly low density and it is produced from open pit mines from countries with low cost labour. However, it is then transported to an aluminium smelter where it is necessary, using the Hall-Heroult Process, to heat the bauxite in the presence of cryolite (Na3AlF6). The bauxite (or alumina) would normally melt at 2000 Celsius but the cryolite reduces the melting point to 1000 Celsius. This still requires enormous heat which when coupled with the electrolysed extraction of the aluminium metal by passing a 150,000 ampere current through the molten material, it can be appreciated that aluminium smelters tend to be located next to dedicated hydro-electric power plants. The vast majority of the cost of producing aluminium from entirely raw materials is NOT in the mining but in the metallurgical recovery of the aluminium metal from its oxide ore. This high metallurgical recovery cost is avoided by recyc
