Preparation method of china supplier aluminum

2021-08-30 16:17:23

In 1854, French chemist Deville mixed bauxite, charcoal, and table salt, and then heated it with chlorine gas to obtain NaCl, AlCl₃ double salt, and then melted this double salt with excess sodium to obtain metal aluminum. In 1886, Howe of the United States and Hylandt of France independently electrolyzed a mixture of molten bauxite and cryolite (Na3AlF6) to produce metallic aluminum, laying the foundation for large-scale aluminum production in the future.

China supplier aluminum exists in various rocks or ore in the form of a chemical state, such as feldspar, mica, kaolinite, bauxite, alunite and so on. Aluminum can be produced by eutectic electrolysis of aluminum oxide and cryolite (Na3AlF6). The main reaction process is as follows:

The reaction process of extracting aluminum from bauxite

Dissolution: Dissolve bauxite in NaOH(aq): Al2O3+ 2NaOH+3H2O= 2NaAl(OH)4 (sodium tetrahydroxy aluminate)

Filtration: Removal of residual ferrous oxide (FeO), sodium aluminosilicate, etc.

Acidification: pass excess CO₂ into the filtrate: NaAl(OH)4+ CO₂ = Al(OH)3↓+ NaHCO3

Filtering and burning Al(OH)₃: 2Al(OH)₃ = high temperature = Al₂O₃+ 3H₂O

Electrolysis:

Note: In order to lower the melting temperature of alumina during electrolysis, cryolite (Na₃AlF6) is added to Al₂O₃. Do not melt AlCl3 electrolytically to make Al; Reason: AlCl3 is a covalent compound, and its molten state has very poor conductivity.