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解説
CF4(88.00)．炭素とフッ素を直接反応させると得られる．無色の気体．融点－185 ℃，沸点－128 ℃．気体分子は正四面体型で原子間距離C-F0.132 nm．熱的にも化学的にも安定である．温室効果ガスの一種である．水に不溶，エタノール，エーテルに易溶．低温用冷媒，気体絶縁体，半導体エッチング，反応容器の洗浄などに用いられる．[CAS 75-73-0]
森北出版「化学辞典（第2版）
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用途
低温冷媒、セミコンダクターや記録ディスク製造時のプラズマエッティングの際のガス状絶縁材
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説明
Tetrafluoromethane, CF4, also known as carbon tetrafluoride and fluorocarbon 14, is a colorless gas that is slightly soluble in water.
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化学的特性
colourless gas
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使用
Low tempereture refrigerant; gaseous insulator.
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一般的な説明
Tetrafluoromethane is a colorless nonflammable gas. Carbon tetrafluoride is shipped as a liquid under pressure. Carbon tetrafluoride may be narcotic at high concentrations. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Carbon tetrafluoride is used as a refrigerant.
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反応プロフィール
The reaction of aluminum with various halogenated hydrocarbons produces a self-sustaining reaction with sufficient heat to melt aluminum pieces, examples of other halogenated hydrocarbons are fluorotrichloromethane, dichlorodifluoromethane, chlorodifluoromethane, tetrafluoromethane. The vigor of the reaction appears to be dependent on the combined degree of fluorination and the vapor pressure [Chem. Eng. News 39(27):44. 1961].
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危険性
Toxic by inhalation.
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健康ハザード
Vapors may cause dizziness or asphyxiation without warning. Vapors from liquefied gas are initially heavier than air and spread along ground. Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. Fire may produce irritating, corrosive and/or toxic gases.
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火災危険
Some may burn but none ignite readily. Containers may explode when heated. Ruptured cylinders may rocket.
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安全性プロファイル
Mddly toxic by
inhalation. Less chronically toxic than
carbon tetrachloride. Violent reaction with
Al. When heated to decomposition it emits
toxic fumes of F-. See also FLUORIDES.
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職業ばく露
Tetrafluoromethane is used in fire extinguishers and as a low temperature refrigerant.
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輸送方法
UN1982 Tetrafluoromethane, compressed or or Refrigerant gas R14, Hazard Class: 2.2; Labels: 2.2Nonflammable gas. 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 permission of the owner.
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純化方法
Purify CF4 by repeated passage over activated charcoal at solid-CO2 temperatures. Traces of air are removed by evacuating while alternately freezing and melting. Alternatively, liquefy CF4 by cooling in liquid air and then fractionally distil it under vacuum. (The chief impurity originally present is probably CF3Cl). Use brass equipment. It is non-flammable. [Beilstein 1 H 59, 1 I 8, 1 II 11, 1 III 35, 1 IV 26.]
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不和合性
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. Forms hydrogen fluoride and fluorides on decomposition with hot surfaces above 125F/52C or open flame. Incompatible with powdered metals; including aluminum, zinc, and beryllium.
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廃棄物の処理
Return refillable compressed gas cylinders to supplier. Nonrefillable cylinders should be disposed of in accordance with local, state and federalregulations. Allow remaining gas to vent slowly into atmosphere in an unconfined area or exhaust hood. Refillabletype cylinders should be returned to original supplier with any valve caps and outlet plugs secured and valve protection caps in place.
