カルシウムジフルオリド 化学特性,用途語,生産方法
外観
白色の粉末
溶解性
水及び有機溶媒にほとんど溶けない。
解説
フッ化カルシウム，水酸化カルシウムまたは炭酸カルシウムをフッ化水素酸で中和すると得られる．天然には蛍石として産出する．無色の等軸晶系結晶．蛍石型構造．格子定数a ＝ 0.545 nm．密度3.18 g cm－3．融点1360 ℃，沸点約2500 ℃．水，エタノールに難溶，アセトンに不溶．濃硫酸と熱するとフッ化水素を発生する．また，フッ化水素酸に解かすと[Ca(HF2)2]･6H2Oが析出する．フッ素化合物，ガラス，ほうろう工業の原料，融剤，赤外分光器のプリズム，紫外分光器の窓，光学薄膜蒸着剤などに用いられる.
用途
高純度金属化合物。
用途
試薬、ふっ素及びその化合物の原料、光学ガラス、光学部品、セル等の原料。
用途
ふっ素及びその化合物の原料、ガラス及びほうろう工業原料。
用途
フッ化カルシウム (フッかカルシウム、calcium fluoride) はカルシウムとフッ素からなる無機化合物で、組成式 CaF2、白色のイオン結晶。天然では蛍石として産出し、フッ素化合物の原料となる。
蛍石は、フッ素化合物の原料として重要であるほか、古くから製鉄などにおいて融剤として用いられてきた。現在では光学レンズの原料として、望遠鏡や写真レンズ（特に望遠）などで、高性能化のための特殊材料としてキーパーツとなっている。他に、セラミックスのフィラーとしても使われる。
高純度のフッ化カルシウム結晶は、紫外線から可視光線、赤外線まで幅広い波長の光（130nm～8μm）を透過することから、光学材料としてレンズや窓板等、多様な用途に使用されている。また、色分散が小さく、さらに一般的な光学ガラスと傾向が違う（異常部分分散）という特性を持つため、これを組み合わせてレンズを作ると色収差が非常に小さい、すなわち広い波長域にわたって焦点距離の差のない極めて安定した光学性能が得られる（蛍石レンズ）。
使用上の注意
純度は金属ベースで差数法によって産出したもので、重量又は容量分析等の化学的方法によるものではありません。使用目的により、正確な含量が必要な場合は、それらの方法により測定する必要があります。
化学的特性
Calcium fluoride, CaF2, also known as fluorite and feldspar, is a colorless solid composed of cubic crystals. It has a low water solubility, but is readily soluble in ammonium salt solutions. Calcium fluoride is used in the synthesis of hydrofluoric acid and in etching glass.
Calcium Fluoride is not hygroscopic and is relatively inert. It has a sufficiently high resistance to thermal and mechanical shock, and it is easily fabricated into a variety of detector geometries.
Calcium Fluoride has a very low vapor pressure, allowing it to be used in a wide variety of vacuum applications. It is insoluble in water and most organic solvents, permitting radioactive samples in solution to be placed in direct contact with the crystal.
Calcium Fluoride is a transparent material used for detecting γ-rays up to several hundred keV and for detecting charged particles. Because of its low atomic number, the material’s photofraction is relatively small which limits its use in γ-ray spectrometry at higher energies. However, the low atomic number makes Calcium Fluoride an ideal material for the detection of β-particles because of the small amount of backscattering.
物理的性質
White cubic crystal or powder; refractive index 1.434; density 3.18 g/cm3; hardness 4 Mohs; melts at 1,418°C; vaporizes at 2,533°C; insoluble in water (16 mg/L at 20°C); Ksp 3.9x10-11; slightly soluble in dilute mineral acid; soluble in concentrated acids (with reaction).
使用
Fluorspar is the main primary source of fluorine and its Compounds. In ferrous metallurgy it is used as a flux to increase the fluidity of the slag. The steel industry is the largest consumer; the chemical industry, second and glass and ceramics, third. Synthetic fluorspar is used in the optical industry (transmits u.v. rays), and pure calcium fluoride is used as catalyst in dehydration and dehydrogenations. Used to fluoridate drinking water.
調製方法
The commercial product is obtained from naturally occurring mineral fluorspar, which is purified and powdered. Also, it may be precipitated by mixing a solution of sodium fluoride with a soluble calcium salt:
Ca(NO
3)
2 + 2NaF → CaF
2 + NaNO
3Alternatively, it may be obtained by treating calcium carbonate with hydrofluoric acid：CaCO
3 + 2HF → CaF
2 + CO
2 + H
2O.
定義
A pure naturally occurring form of calcium fluoride.
一般的な説明
Odorless gray powder or granules. Sinks in water.
反応プロフィール
Calcium fluoride has weak oxidizing or reducing powers. Redox reactions can however still occur. The majority of compounds in this class are slightly soluble or insoluble in water. If soluble in water, then the solutions are usually neither strongly acidic nor strongly basic. These compounds are not water-reactive.
危険性
An irritant.
健康ハザード
Little acute toxicity
工業用途
Also called fluorite, fluorspar is a crystalline or massive granular mineral of the composition CaF
2, used as a flux in the making of steel, for making hydrofluoric acid, in opalescent glass, in ceramic enamels, for snaking artificial cryolite, as a binder for vitreous abrasive wheels,and in the production of white cement. It is a better flux for steel than limestone, making a fluid slag, and freeing the iron of sulfur and phosphorus.
Acid spar is a grade used in making hydrofluoric acid. It is also used for making refrigerants, plastics, and chemicals, and for aluminum reduction. Optical fluorspar is the highest grade but is not common. Fluoride crystals for optical lenses are grown artificially from acid-grade fluorspar. Pure calcium fluoride, Ca
2F
6, is a colorless crystalline powder used for etching glass, in enamels, and for reducing friction in machine bearings. It is also used for ceramic parts resistant to hydrofluoric acid and most other acids. Calcium fluorite has silicon in the molecule and is a crystalline powder used for enamels. The clear rhombic fluoride crystals used for transforming electric energy into light are lead fluoride, PbF
2.
安全性プロファイル
Moderately toxic by
intraperitoneal route. Mildly toxic by
ingestion. An experimental teratogen. Other
experimental reproductive effects. Mutation
data reported. See also FLUORIDES and
CALCIUM COMPOUNDS. When heated
to decomposition it emits toxic fumes of F-.
職業ばく露
Calcium fluoride is used for production of hydrofluoric acid; as a flux in steel manufacture; in
smelting; electric arc welding, making glass and ceramics;
and to fluoridate drinking water.
輸送方法
Calcium fluoride is not specifically covered by
DOT in its Performance-Oriented Packaging Standards.
不和合性
Dust may form explosive mixture with
air. Reacts with water, moist air, and steam, releasing flammable hydrogen gas; and may self-ignite in air. A strong
reducing agent; incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Incompatible with metal
halogenates, silver fluoride, and tetrahydrofuran
カルシウムジフルオリド 上流と下流の製品情報
原材料
準備製品