Hall-Héroult process
Quick Summary
The Hall-Héroult process is an industrial method for producing aluminum. Discovered independently by Charles Martin Hall in the United States and Paul-Louis-Toussaint Héroult in France in 1886, this process revolutionized aluminum production. It involves dissolving purified alumina (aluminum oxide) in molten cryolite and then using direct electric current to electrolyze the mixture. The oxygen from the alumina is released as carbon dioxide at the carbon anode, while molten aluminum collects at the carbon lining of the cell, which acts as the cathode. This electrolytic process made aluminum affordable and widely available for various applications.123
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metallurgyElectrolytic smeltingIn the Hall-Héroult smelting process, a nearly pure aluminum oxide compound called alumina is dissolved at 950 °C (1,750 °F) in a molten electrolyte composed of aluminum, sodium, and fluorine; this is electrolyzed to give aluminum metal at the cathode and oxygen gas at the anode. The…
Read MoreIn the Hall-Héroult smelting process, a nearly pure aluminum oxide compound called alumina is dissolved at 950 °C (1,750 °F) in a molten electrolyte composed of aluminum, sodium, and fluorine; this is electrolyzed to give aluminum metal at the cathode and oxygen gas at the anode. The…
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Use of the Hall-Héroult process on an industrial scale depended on the replacement of storage batteries by rotary power generators; it remains essentially unchanged to this day.
Read MoreUse of the Hall-Héroult process on an industrial scale depended on the replacement of storage batteries by rotary power generators; it remains essentially unchanged to this day.
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aluminum processingSmelting…been found for the Bayer-Hall-Héroult approach.
Read More…been found for the Bayer-Hall-Héroult approach.
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