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The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) (obtained most often from bauxite , aluminium 's chief ore, through the Bayer process ) in molten cryolite and electrolyzing the molten salt bath, typically in a purpose-built cell.
The Bayer process is the principal industrial means of refining bauxite to produce alumina (aluminium oxide) and was developed by Carl Josef Bayer. Bauxite, the most important ore of aluminium , contains only 30–60% aluminium oxide (Al 2 O 3 ), the rest being a mixture of silica , various iron oxides , and titanium dioxide . [ 1 ]
Alumina is extracted from the ore bauxite by means of the Bayer process at an alumina refinery. This is an electrolytic process, so an aluminium smelter uses huge amounts of electric power; smelters tend to be located close to large power stations, often hydro-electric ones, in order to hold down costs and reduce the overall carbon footprint ...
Aluminium production possesses its own challenges to the environment on each step of the production process. The major challenge is the greenhouse gas emissions. [200] These gases result from electrical consumption of the smelters and the byproducts of processing. The most potent of these gases are perfluorocarbons from the smelting process. [200]
Aluminium recycling is the process in which secondary commercial aluminium is created from scrap or other forms of end-of-life or otherwise unusable aluminium. [1] It involves re-melting the metal, which is cheaper and more energy-efficient than the production of virgin aluminium by electrolysis of alumina (Al 2 O 3 ) refined from raw bauxite ...
An overview of the Hot Form Quench process. Hot forming of aluminium alloys consists of four main steps performed on a custom-shaped sheet blank: heating and solutionising (above 450°C), blank transfer, quenching (to near ambient temperature) and forming, and artificial aging. In the solutionising step, the blank is heated in a furnace to a ...
Carl Josef Bayer (also Karl Bayer, 4 March 1847 – 4 October 1904) was a chemist from Austria-Hungary who invented the Bayer process of extracting alumina from bauxite, essential to this day to the economical production of aluminium.
This is a list of primary aluminium smelters in the world. Primary production is the process by which alumina is smelted to pure aluminum. [1] Secondary production is the process of recycling aluminum scrap into aluminum that can be used again. [2]