Production of aluminium
Although aluminium is very common in the earth’s crust, its production used to be one of the very difficult processes in industry.
This is mostly due to the fact that it is impossible to streamline from its ore in a simple way, e.g. iron through coke in a high furnace.
Only once the method of industrial electrolysis and melting was managed did it become possible to produce hundreds of tonnes of pure aluminium on a yearly basis, as is currently the case.
Elementary aluminium is extracted on a cathode at a temperature of 950° C when electrolysis is used on the melted mixture of previously cleaned bauxite and cryolite. Oxygen forms on the graphite anode and immediately reacts with the electrode material whereby toxic carbon monoxide gas occurs, CO.