How do you get aluminum from the ground?

Answer 1

Aluminum metal is too reactive chemically to occur as pure aluminum in nature. Instead, it is found combined in over 270 different minerals. The main ore from which aluminum is extracted is bauxite. Bauxite is usually strip mined because it is almost always found near the surface of the terrain, with little or no overburden. Approximately 95% of the world's bauxite production is processed first into alumina, and then into aluminium by electrolysis.

Bauxite is converted to alumina by first heating it in a pressure vessel along with a sodium hydroxide solution at a temperature of 150 to 200 °C. At these temperatures, the aluminum in the bauxite is dissolved as an aluminate (the Bayer process). After separation from the residual mud (from which most of the aluminum has already been extracted) by filtering, pure gibbsite is precipitated when the liquid is cooled, and then seeded with fine-grained aluminium hydroxide. The gibbsite is usually converted into alumina (aluminum oxide, Al2O3), by heating.

The alumina is then mixed with cryolite (Na3AlF6, sodium hexafluoroaluminate) and heated to about 1000 °C. The cryolite helps the alumina form a liquid solution. The aluminum is then separated by passing a lot of electricity through it (electrolysis). This separation is called the Hall--Héroult process after the men who developed it. Before the Hall--Héroult process was invented, producing aluminum was much more time consuming and expensive - to the point that aluminum dishes and utensils were considered more exotic and a mark of greater wealth than gold or silver dishes and utensils. Napoleon III, Emperor of France, is reputed to have given a banquet where the most honoured guests were given aluminum utensils, while the others made do with gold.

Answer 2

Aluminum is extracted from bauxite ore in a process called the Bayer process which involves crushing and dissolving bauxite in sodium hydroxide. The extracted aluminum is then electrolyzed to produce aluminum metal.