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The global market for chemicals from fluorine was about US$16 billion per year as of 2006.〔(【引用サイトリンク】url=http://www.freedoniagroup.com/brochure/15xx/1555smwe.pdf )〕 The industry was predicted to reach 2.6 million metric tons per year by 2015. The largest market is the United States. Western Europe is the second largest. Asia Pacific is the fastest growing region of production.〔 China in particular has experienced significant growth as a fluorochemical market and is becoming a producer of them as well. Fluorite mining (the main source of fluorine) was estimated in 2003 to be a $550 million industry, extracting 4.5 million tons per year. Mined fluorite is separated into two main grades, with about equal production of each. ''Acidspar'' is at least 97% CaF2; ''metspar'' is much lower purity, 60–85%. (A small amount of the intermediate, ''ceramic'', grade is also made.)〔〔 Metspar is used almost exclusively for iron smelting. Acidspar is primarily converted to hydrofluoric acid (by reaction with sulfuric acid). The resultant HF is mostly used to produce organofluorides and synthetic cryolite. Image:The fluorine economy.svg|thumb|675px|center|Fluorine industry supply chain: major sources, intermediates and applications. Click for links to related articles. rect 9 6 81 34 Fluorite rect 9 172 81 199 Fluorapatite rect 142 5 244 34 Hydrogen fluoride rect 142 65 245 97 Metal smelting rect 142 121 244 154 Glass production rect 309 5 411 33 Fluorocarbons rect 310 63 413 92 Sodium hexafluoroaluminate rect 311 121 414 154 Pickling (metal) rect 310 171 412 200 Fluorosilicic acid rect 309 211 412 243 Alkane cracking rect 483 6 585 34 Hydrofluorocarbons rect 484 47 585 76 Hydrochlorofluorocarbons rect 483 88 586 116 Chlorofluorocarbon rect 483 128 585 160 Teflon rect 484 170 586 200 Water fluoridation rect 483 210 586 238 Uranium enrichment rect 484 258 586 287 Sulfur hexafluoride rect 484 297 585 357 Tungsten hexafluoride rect 28 246 177 293 Phosphogypsum desc bottom-left ==Inorganic fluorides== About 3 kg (6.5 lb) of metspar grade fluorite, added directly to the batch, are used for every metric ton of steel made. The fluoride ions from CaF2 lower the melt's temperature and viscosity (make the liquid runnier). The calcium content has a tangential benefit in removing sulfur and phosphorus, but other additives such as lime are still needed. Metspar is similarly used in cast iron production and for other iron-containing alloys.〔 Fluorite of the acidspar grade is used directly as an additive to ceramics and enamels, glass fibers and clouded glass, and cement, as well as in the outer coating of welding rods.〔 Acidspar is primarily used for making hydrofluoric acid, which is a chemical intermediate for most fluorine-containing compounds. Significant direct uses of HF include pickling (cleaning) of steel, cracking of alkanes in the petrochemical industry, and etching of glass.〔 One third of HF (one sixth of mined fluorine) is used to make synthetic cryolite (sodium hexafluoroaluminate) and aluminium trifluoride. These compounds are used in the electrolysis of aluminium by the Hall–Héroult process. About 23 kg (51 lb) are required for every metric ton of aluminium. These compounds are also used as a flux for glass.〔 Fluorosilicates are the next most significant inorganic fluorides formed from HF. The most common one, that of sodium, is used for water fluoridation, as an intermediate for synthetic cryolite and silicon tetrafluoride, and for treatment of effluents in laundries. MgF2 and, to a lesser extent, other alkaline earth difluorides are specialty optical materials. Magnesium difluoride is widely used as an antireflection coating for spectacles and optical equipment. The compound is also a component in newly devised constructions (negative index metamaterials) which are the subject of "invisibility" research. The layered structures can curve light around objects. Other inorganic fluorides made in large quantities include cobalt difluoride (for organofluorine synthesis), nickel difluoride (electronics), lithium fluoride (a flux), sodium fluoride (water fluoridation), potassium fluoride (flux), and ammonium fluoride (various).〔 Sodium and potassium bifluorides are significant to the chemical industry. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fluorochemical industry」の詳細全文を読む スポンサード リンク
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