Aluminium is the most abundant metal in the Earth’s crust. Since the discovery of bauxite in 1821 by P. Bertheir, the metal has gradually evolved as a cheap, durable metal which finds applications in several industries.
The metal originally obtained its name from the Latin word for alum, alumen. The name alumina was proposed by L. B. G. de Moreveau, in 1761 for the base in alum and it was successfully shown in 1787 that the base was the oxide of a yet to be discovered metal. The existence of aluminium was established by Sir Humphry Davy in 1808.
Initially, aluminium was produced by reduction with alkali metals and was very expensive. In 1886 C. M. Hall and Paul Héroult, working independently, came up with a cost-effective solution called the Hall-Héroult electrolytic process that refined aluminium production. In this process, the aluminium oxide is dissolved in molten cryolite and then reduced to the pure metal. The Bayer process was deployed to purify the raw material alumina, recover it from sodium hydroxide and used in the Hall-Héroult process.
The Hall-Héroult process consumes a lot of energy but the development of alternative processes was scrapped due to technical problems and also because these were economically unviable. Therefore, the Hall-Héroult process has remained the relatively inexpensive mode of producing aluminium.
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