from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An uncommon, white, vitreous natural fluoride of aluminum and sodium, Na3AlF6, nearly invisible in water in powdered form and used chiefly in the electrolytic recovery of aluminum. Also called Greenland spar.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The mineral sodium aluminium fluoride (Na3AlF6).
from the GNU version of the Collaborative International Dictionary of English
- n. A fluoride of sodium and aluminum, found in Greenland, in white cleavable masses; -- used as a source of soda and alumina.
from The Century Dictionary and Cyclopedia
- n. A fluorid of sodium and aluminium found in Greenland, where it forms an extensive bed.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a white mineral consisting of fluorides of aluminum and sodium; a source of fluorine
Sorry, no etymologies found.
At the smelter, the aluminum oxide crystals are dissolved in a bath of something called cryolite (sodium aluminum fluoride) and zapped with enormous jolts of electricity (100,000 to 150,000 amps), which strips the oxygen from the aluminum.
It was at first manufactured from common clay, which contains about one-fourth its weight of aluminum, but in 1855 Rose announced to the scientific world that it could be obtained from a material called "cryolite," found in Greenland in large quantities, imported into Germany under the name of "mineral soda," and used as a washing soda and in the manufacture of soap.
At length he tried a stone from Greenland called "cryolite," which had already been used for making a kind of porcelain.
This process also breaks off bits of the fluorine from the cryolite, which escapes the smelter in the form of perfluorocarbons PFCs—these are the most noxious of greenhouse gases, trapping thousands of times more heat than carbon dioxide.
Hall, fresh out of Oberlin College in 1886, tried dissolving the aluminum salt in a fused-cryolite (sodium aluminum fluoride) bath instead of water.
In this process, alumina (aluminum oxide) is dissolved in molten cryolite (cryolite is an aluminum fluoride mineral, Na3AlF6).
The basis of Hall's invention involves "passing an electric current through a bath of alumina dissolved in cryolite, which results in a puddle of aluminum forming in the bottom of the retort."
He produced his first small bits of aluminum using the cryolite, aluminum oxide and homemade batteries.
After years of intensive work in which he had to fabricate most of his apparatus and prepare his chemicals, Hall found the solvent he needed: molten cryolite, the mineral sodium aluminum fluoride on February 23, 1886.
In order to produce aluminum from alumina on Earth, the alumina is dissolved in molten cryolite at 1,000°C and then electrolyzed with carbon electrodes, which are used up in the process, while the cryolite is unharmed.
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