kryoliitin

Kryoliitti, also known as sodium aluminum fluoride, is a mineral with the chemical formula Na3AlF6. It is a white or colorless crystalline solid and is relatively rare in nature, occurring primarily in Greenland. Historically, kryoliitti was mined in large quantities in Ivittuut, Greenland, for its crucial role in the industrial production of aluminum.

The primary use of kryoliitti is as a solvent in the electrolytic production of aluminum. When aluminum oxide (alumina) is dissolved in molten kryoliitti, the melting point of alumina is significantly lowered, making electrolysis more energy-efficient and economically viable. This process, known as the Hall-Héroult process, revolutionized aluminum smelting. Although synthetic kryoliitti is now produced industrially and is more commonly used, natural kryoliitti was essential for its development.

Beyond its use in aluminum production, kryoliitti has found applications in other areas. It has been employed as a flux in metallurgical processes, particularly in smelting and refining metals. It has also been used in the production of glass and enamels, where it acts as a whitening agent and aids in melting. In some specialized applications, it has been used in insecticides and as a filler. Due to its declining industrial importance and the availability of synthetic alternatives, the mining of natural kryoliitti has largely ceased.