Annual magnesium metal

Most zirconium is used as an oxide in commercial applications. Only a few percent is converted to the metal and used in chemical process industries because of its excellent corrosion resistance, while a special grade of zirconium is used in the nuclear industry. There are no official statistics for the production and consumption of zirconium metal. The annual global production capacity is estimated approximately at 85001, and total production/consumption is about 7000 t/year. The main applications of zirconium metal are for the nuclear energy and chemical process industries. About 85% of zirconium metal, 5000-6000 t/year, is used in the nuclear industry. Commercial-quality zirconium still contains 1 -3% hafnium. This contaminant is unimportant except in nuclear applications. For nuclear reactor materials, the zirconium metal should have a very low hafnium content of less than 0.01 wt%. Most Zr metal is produced by the reduction of the zirconium (ZrCy chloride with magnesium metal in the Kroll process. 

USSR 76 and Brazil 37 tonnes of contained Be, which together accounted for 98% of world production. The cost of Be metal was 690/kg in 1987. By contrast, world supplies of magnesium are virtually limitless it occurs to the extent of 0.13% in sea water, and electrolytic extraction at the present annual rate, if continued for a million years, would only reduce this to 0.12%. 

Compounds of cerium and its relatives find numerous suggested uses. The pyrophoric metal known as " kunheim is a mixture of the hydrides of the cerium earth metals with magnesium and aluminium. Cerium fluoride and titanofluoride have been used in the preparation of electrodes for the flaming arc light. By impregnating the carbon electrodes with the cerium salts a more intense light is obtained and the arc bums evenly and quietly. Steam declares 1 that 300 tons of ceria are used annually for this purpose. 

Magnesium (Mg) is a valuable metal used in alloys, in batteries, and in the manufacture of chemicals. It is obtained mostly from seawater, which contains about 1.3 g of Mg for every kilogram of seawater. Referring to Problem 1.69, calculate the volume of seawater (in liters) needed to extract 8.0 X 10 tons of Mg, which is roughly the annual production in the United States. 

Zircon silicate is the most important source of hafnium. Ion-exchange and solvent-extraction techniques have supplanted fractional crystallization and distillation as the preferred methods of separating hafnium from zirconium. The metal itself is prepared by magnesium reduction of hafnium tetrachloride (the Kroll process), and by the thermal decomposition of tetraiodide (de Boer-van Arkel process). The annual world production of hafnium metal was about 40 tons at the end of the 1980s (Soloveichik... 

T HE alkali metals constitute a chemical family of growing importance. The big boy of the family is sodium, of course, really a heavy chemical with world production on the order of 300,000,000 poimds annually. It is not a well balanced child, however, in that some 60% goes into the manufacture of a single chemical—tetraethyllead. But healthy signs include the commercial manufacture of isosebacic acid and a swing from magnesium to the sodium processes for titanium manufacture. 

As a conclusion, it is foimd to be economic to use SO2 instead of SFg as a cover gas in magnesium die-casting, at least in plants with an annual metal output of 500 tonnes and more, regardless of whether the plant is to be newly built or still runs with SFe. 

These metals are all produced by electrolysis of a mixture of molten metal chlorides the electrolyte composition is selected to minimize the process temperature and to ensure that it is the desired metal that is discharged at the cathode. The estimated annual world production of sodium and magnesium is a few hundred thousand tons while that for lithium is only a few thousand tons. The... 

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