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解説
フッ素，元素記号F，原子番号9，原子量 18.9984032。安定同位体はフッ素 19のみである。周期表 17族，ハロゲンの1つ。天然には蛍石，氷晶石などとして産出する。地殻における存在量 625ppm，海水中の平均濃度 1.3 mg/l 。フッ素の存在は 16世紀頃から知られていたが，単体の形で得たのは H.モアッサンである (1886) 。単体は二原子分子 F2 で，常温では黄緑色の特異臭ある気体である。沸点－188℃。化学作用は劇甚で，希ガスの一部を除くすべての元素と直接反応する。銅およびニッケルはフッ化物の薄膜を生じ，内部はおかされないので，反応容器などに使用される。第2次世界大戦中に工業的規模での生産がアメリカで開始された。冷媒，フッ素樹脂，防腐剤，殺虫剤など広範な用途をもっている。
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用途
強化剤
冷媒、樹脂、洗浄剤、製鋼滓化剤等幅広い用途
蛍石（CaF2 ）、氷晶石(Na2AlF3)、リン灰石（Ca5(PO4)3F）などの鉱物から産出される。フッ素化合物の主な出発原料は、フッ化水素であり、主に蛍石から生産されている。最大需要用途は、エアコン冷媒等に使用されるフロンである。フッ素樹脂は耐熱性、耐薬品性、絶縁性等に優れ、フライパンから輸送機器におけるオイルシール、軸受、精密機械、電子基板など広い範囲で用いられている。フッ酸は半導体製造用のエッチング、液晶ガラスの薄化やステンレス製造用洗浄剤に用いられている。その他、リチウム電池用電解質、触媒、CVD洗浄ガスなどフッ素の用途は幅広い。
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性質
常温で二原子分子F2からなる淡黄色の気体。刺激臭が強く有毒である。液体フッ素はきわめて反応性が強く皮膚、粘膜などを侵す猛毒である。F-F結合間隔は1.418Å、解離エネルギーは155キロジュール／モル。液体は淡黄色で、低温になるにつれ無色に近づく。酸素、窒素以外のほとんどすべての元素と直接化合する。水素とは暗所でも爆発的に化合してフッ化水素をつくる。金、白金とも高温で反応して高級酸化数のフッ化物をつくる。銅は表面にフッ化物の膜を生じ、内部は侵されない。水と激しく反応して酸素、フッ化水素のほかにオゾン、過酸化水素、二フッ化酸素を生じる。
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説明
Fluorine is a highly toxic, pale yellow gas about
1.3 times as heavy as air at atmospheric temperature
and pressure. When cooled below its
boiling point (-306.8°F or -188.2°C), it is a
liquid about 1.5 times as dense as water.
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化学的特性
Fluorine (F) is a chemical element(group VIla, halogens).It is a pale yellow,highly toxic, corrosive, flammable gas. It is a stable, extremely strong oxidant, which may react violently with combustible materials, including plastics, reducing agents, and organic material. It reacts with water to form corrosive acids. Fluorine is very toxic and may be fatal if inhaled. Fluorine reacts violently with many oxidising agents (e.g. perchlorates, peroxides, permanganates, chlorates, nitrates, chlorine, bromine, and fluorine), strong acids (hydrochloric, sulphuric, and nitric), organic compounds, combustible materials like oil and paper, hydrogen, bromine, iodine, and chemically active metals like, potassium, sodium, magnesium, and zinc.
Fluorine is the most electro negative of all elements and the most chemically energetic of all nonmetallic elements. Fluorine is a high-tonnage chemical that is used in production of fluorides, in synthesis of fluorocarbons,and as an oxidizer for rocket fuels. Because of its severe oxidizing characteristics, special permits are required for shipping of fluorine,and all containers,piping,and processing equipment used for fluorine service must be passivated prior to use. Thereafter, they must be designated for exclusive fluorine service.
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物理的性質
Fluorine does not occur in a free state in nature, and because fluorine is one of the mostreactive elements, no chemical can free it from any of its many compounds. The reason forthis is that fluorine atoms are the smallest of the halogens, meaning the electron donated by ametal (or some nonmetals) are closer to fluorine’s nucleus and thus exert a great force betweenthe fluorine nuclei and the elements giving up one electron. The positive nuclei of fluorinehave a strong tendency to gain electrons to complete the outer shell, which makes it a strongoxidizer.
Because the fluorine atom has only nine electrons, which are close to the nucleus, thepositive nucleus has a strong tendency to gain electrons to complete its outer shell. As a gasits density (specific gravity) is 1.695, and as a liquid, its density is 1.108. Its freezing point is–219.61°C, and its boiling point is –188°C. Fluorine, as a diatomic gas molecule (F2), is paleyellow in color. Fluorine is the most electronegative nonmetallic element known (wants togain electrons) and is, therefore, the strongest oxidizing agent known.
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同位体
There are a total of 16 isotopes of fluorine. Only one, F-19, is stable. It makesup 100% of the fluorine found on Earth. All the others are radioactive with half-livesranging from 2.5 milliseconds to 4.57100×10-22 years.
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名前の由来
From the Latin and French words for “flow,” fluere.
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天然物の起源
Fluorine is the 13th most abundant element on the Earth. It makes up about 0.06% of theEarth’s crust. Fluorine is widely distributed in many types of rocks and minerals, but neverfound in its pure form. Fluorine is as plentiful as nitrogen, chlorine, and copper, but lessplentiful than aluminum or iron.
The most abundant fluorine mineral is fluorite—calcium fluoride (CaF2)—which is oftenfound with other minerals, such as quartz, barite, calcite, sphalerite, and galena. It is mined in Cumberland, England, and in Illinois in the United States. Other minerals from which fluorineis recovered are fluorapatite, cryolite, and fluorspar, which are found in many countriesbut mainly in Mexico and Africa.
Today fluorine is produced by the electrolysis of potassium fluoride (KF), hydrofluoric acid(HF), and molten potassium acid fluoride (KHF2).
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特性
Fluorine reacts violently with hydrogen compounds, including water and ammonia. It alsoreacts with metals, such as aluminum, zinc, and magnesium, sometimes bursting into flames,and with all organic compounds, in some cases resulting in such complex fluoride compoundsas fluorocarbon molecules. It is an extremely active, gaseous element that combines spontaneouslyand explosively with hydrogen, producing hydrogen fluoride acid (HF), which is usedto etch glass. It reacts with most metals except helium, neon, and argon. It forms many differenttypes of “salts” when combining with a variety of metals. Fluorine, as a diatomic gas,is extremely poisonous and irritating to the skin and lungs, as are many fluoride compounds.Fluorine and its compounds are also corrosive.
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使用
Fluorine is used in the manufacture of vari ous fluorocarbons and fluorides, as a rocketpropellant, and in many inorganic and or ganic syntheses.
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定義
Nonmetallic halogen element in group 17 of the periodic table. An 9, aw 18.99840, valence of 1, no other
stable isotopes, the most electronegative element
and most powerful oxidizing agent known.
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製法
工業的には電解法によって製造される。電解浴のKF:HFの組成比により、高温法（1:1、約250℃）と中温法（1:2、約100℃）がある。電解槽（陰極となる）、隔膜に銅、モネル合金または鋼、陽極に炭素材料が用いられる。
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一般的な説明
Fluorine is a pale yellow gas with a pungent odor. Fluorine is commonly shipped as a cryogenic liquid. Fluorine is toxic by inhalation and skin absorption. Contact with skin in lower than lethal concentrations causes chemical burns. Fluorine reacts with water to form hydrofluoric acid and oxygen. Fluorine is corrosive to most common materials. Fluorine reacts with most combustible materials to the point that ignition occurs. Under prolonged exposure to fire or intense heat the containers may violently rupture and rocket.
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空気と水の反応
Water vapor will react combustibly with Fluorine; an explosive reaction occurs between liquid Fluorine and ice, after an intermediate induction period, [NASA SP-3037: 52(1967)]: If liquid air, which has stood for some time is treated with Fluorine, a precipitate is formed which is likely to explode. Explosive material is thought to be Fluorine Hydrate, [Mellor 2:11(1946-1947)].
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危険性
Many of the fluorine compounds, such as CFCs, are inert and nontoxic to humans. Butmany other types of compounds, particularly the salts and acids of fluorine, are very toxicwhen either inhaled or ingested. They are also strong irritants to the skin.
There is also danger of fire and explosion when fluorine combines with several elementsand organic compounds.
Poisonous fluoride salts are not toxic to the human body at the very low concentrationlevels used in drinking water and toothpaste to prevent dental decay.
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健康ハザード
reactions; highly irritating and corrosive to the eyes, skin, and mucous membranes.
Toxicity The acute toxicity of fluorine is high. Even very low concentrations irritate the
respiratory tract, and brief exposure to 50 ppm can be intolerable. High
concentrations can cause severe damage to the respiratory system and can result in
the delayed onset of pulmonary edema, which may be fatal. Fluorine is highly
irritating to the eyes, and high concentrations cause severe injury and can lead to
permanent damage and blindness. Fluorine is extremely corrosive to the skin,
causing damage similar to second-degree thermal bums. Fluorine is not considered
to have adequate warning properties.
Chronic toxicity is unlikely to occur due to the corrosive effects of fluorine
exposure. Fluorine has not been found to be carcinogenic or to show reproductive or
developmental toxicity in humans.
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火災危険
Fluorine is not flammable, but is a very strong oxidizer, reacting vigorously with
most oxidizable materials at room temperature, frequently with ignition. Water
should not be used to fight fires involving fluorine
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燃焼性と爆発性
Fluorine is not flammable, but is a very strong oxidizer, reacting vigorously with most oxidizable materials at room temperature, frequently with ignition. Water should not be used to fight fires involving fluorine.
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农业用途
Fluorine is the lightest of the halogens, occurring naturally in fluorapatite, fluorite and cryolite. A pale yellow toxic gas, fluorine is made by electrolysis of potassium fluoride in liquid hydrogen fluoride. It is the most reactive, electronegative and oxidizing of all elements, and reacts with almost all elements, giving fluorides. It is used in rocket propulsion and in the production of uranium and fluorocarbons.
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材料の用途
Nickel, iron, aluminum, magnesium, copper,
and certain of their alloys are quite satisfactory
for handling fluorine at room temperature, for
these are among the metals with which formation
of a surface fluoride film retards further
reaction.
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職業ばく露
Elemental fluorine is used in the con version of uranium tetrafluoride to uranium hexafluoride;
in the synthesis of organic and inorganic fluorine com pounds; and as an oxidizer in rocket fuel.
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特性
フッ素原子はすべての元素の中で最も電気陰性度が高い
単体は二原子分子（F2）の淡黄緑色、特異臭のある気体で
極めて激しい化学反応性を有
し、全ての元素と直接反応する
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環境運命予測
Fluorine remains persistent in the environment. In water,
fluorides attach to aluminum in freshwater and calcium and
magnesium in seawater and settle into the sediment. Fluorides
may be taken up from soil and accumulate in plants or
they may be deposited on the upper parts of the plants. The
amount of fluoride taken up by plants depends on the type of
plant, the nature of the soil, and the amount and form of
fluoride in the soil. Levels of fluorides in surface water
average about 0.2 ppm, while well water levels range from
0.02 to 1.5 ppm. The 15 000 water systems serving about 162
million people in the USA are fluoridated in the range of
0.7–1.2 ppm.
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貯蔵
Work with fluorine requires special precautions and protective equipment and should be carried out only by specially trained personnel. Fluorine will react with many materials normally recommended for handling compressed gases.
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輸送方法
UN1045 Fluorine, compressed, Hazard Class:
2.3; Labels: 2.3-Poisonous gas, 5.1-Oxidizer, 8-Corrosive
material, Inhalation Hazard Zone A. Cylinders must be
transported in a secure upright position, in a well-ventilated
truck. Protect cylinder and labels from physical damage.
The owner of the compressed gas cylinder is the only entity
allowed by federal law (49CFR) to transport and refill
them. It is a violation of transportation regulations to refill
compressed gas cylinders without the express written per mission of the owner.
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純化方法
Pass the gas through a bed of NaF at 100o to remove HF and SiF4. [For description of stills used in fractional distillation, see Greenberg et al. J Phys Chem 65 1168 1961; Stein et al. Purification of Fluorine by Distillation, Argonne National Laboratory, ANL-6364 1961 (from Office of Technical Services, US Dept of Commerce, Washington 25).] HIGHLY TOXIC.
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不和合性
Fluorine is an extremely powerful oxi dizing gas. Keep away from heat, water, nitric acid, oxidi zers, organic compounds. Containers may explode if
heated. Reacts violently with reducing agents; ammonia, all
combustible materials, metals (except the metal containers
in which it is shipped). Reacts violently with H2O to form
hydrofluoric acid, oxygen and ozone. The most potent
oxidizer.
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廃棄物の処理
Return refillable compressed
gas cylinders to supplier. Fluorine may be combusted by
means of a fluorine-hydrocarbon air burner followed by a
caustic scrubber and stack. Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform with EPA regulations gov erning storage, transportation, treatment, and waste
disposal.
