Sodium aluminum hexafluoride

Aluminum oxide is added in an amount of 7 to 12%, dependent upon the bath composition. The eutectic mixture, sodium aluminum hexafluoride/aluminum oxide with 10.5% aluminum oxide, melts at 960°C. The yield with respect to current consumed is 85 to 95%, the cell voltage is 4,5 to 5%, the anode consumption is ca. 0.5 kg/kg aluminum, the power rating of a plant - consisting of many (100 to 200) individual cells connected in series - is in the range 50 to 300 kA. 

Sodium fluoroaluminate CAS 15096-52-3 EINECS/ELINCS 215-560-3 Synonyms Aluminum sodium fluoride Cryolite Sodium aluminofluoride Sodium aluminum fluoride Sodium aluminum hexafluoride Sodium fluoaluminate Sodium hexafluoroaluminate... 

It is witnessed that combustion products of the mixture AIF3 -I- 3NaNg over nitrogen pressure 4 MPa consist of three phases aluminum nitrogen, sodium aluminum hexafluoride, and sodium fluoride. On the assumption of the reflex magnitude relation it is fair to assume that Nag AlFg < AIN < NaF. 

Electrowinning of Aluminum. Aluminum, the most abundant metal in the Earth s crust, did not become readily available commercially until the development of the Hall-Heroult process. This process involves electrolysis of dry aluminum oxide (alumina) dissolved in cryolite (sodium aluminum hexafluoride). Additional calcium fluoride is used to lower the melting point of the cryolite. The process runs at about 960 degrees Celsius and uses carbon electrodes. The alumina for the Hall-Heroult process is obtained from an ore called bauxite, an impure aluminum oxide with varying amounts of compounds such as iron oxide and silica. The preparation of pure alumina follows the Bayer process The alumina is extracted from the bauxite as a solution in sodium hydroxide (caustic soda), reprecipitated by acidification, filtered, and dried. The electrolysis cell has a carbon coating at the bottom that forms a cathode. 

Hydrogen cyanide Iron oxide black Mercury chloride (ic) Nickel cyanide Nitric acid Sodium chloride Sulfurous acid Zirconium potassium hexafluoride metallurgy, aluminum Sodium silicofluoride metallurgy, beryllium Sodium silicofluoride metallurgy, ore separation Phosgene metals... 

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