塩化コバルト(II) 化学特性,用途語,生産方法
外観
青紫色, 粉末又は塊
定義
本品は、コバルトの塩化物であり、次の化学式で表される。
溶解性
水に易溶 (45g/100g水, 7℃), エタノールに可溶, エーテルに難溶。水に極めて溶けやすく、エタノール及びアセトンにやや溶けやすい。
解説
塩化コバルト(II),えんかコバルト,化学式 CoCl2 。コバルトの粉末に塩素を作用させて得られる。淡青色，葉片状の吸湿性結晶。湿った空気に触れると淡紅色に変る。融点 735℃，沸点 1049℃，比重 3.37。6水和物は [CoCl2(H2O)4]・2H2O の構造をとり，淡紅色ないし赤色で，弱い潮解性のプリズム状結晶。融点 86℃，比重 1.92。加熱すると 52～56℃で 4H2O を失い，紫青色の2水和物 (比重 2.48) になる。 100℃でさらに水1分子を失い，紫色，吸湿性の針状または無定形固体に変る。 120～140℃で完全に脱水する。水，アルコール，アセトンに可溶。水溶液は淡紅色だが，加熱あるいは塩酸，硫酸の添加により青色となる。あぶり出し用インキ，湿度指示剤，メッキ，ガラスや磁器の着色剤，触媒，肥料などに対する添加剤，毒ガスやアンモニアの吸収剤，ビタミン B12 の製造など，用途は広い。
用途
無水物から水和物へと吸湿して変化してゆくにつれて青から赤へと色調が変わり、水を失う場合は可逆的で色調が変化するので、シリカゲルなどに水分の指示薬として添加される。他にも示温顔料、ガラス、陶器の着色、ビールの泡の安定剤、植物が取り込む物質を調べる時、ビタミンB12の原料などにも利用される。
用途
シリカゲル
用途
触媒。有機合成(和光試薬時報Vol.63 No.1,p.27(1995))。
説明
blue crystals (anhydrous)
violet-blue (dihydrate)
rose red crystals (hexahydrate)
Sinks and mixes with water. Pale blue leaflets, turns pink upon exposure to moist air.
化学的特性
Cobalt chloride (CoCl₂) is a purplish-red or red monoclinic crystal that is slightly weathered and easily deliquescent. It has a melting point of 724°C and is soluble in water, ethanol, ether, and acetone. The anhydrous compound has the molecular formula CoCl₂, containing 45.4% cobalt and 54.6% chlorine. The monohydrate compound has the molecular formula CoCl₂·H₂O, containing 39.9% cobalt. The hexahydrate compound has the molecular formula CoCl₂·6H₂O, containing 24.8% cobalt.
Cobalt chloride crystals are stable at room temperature but lose water of crystallization and turn blue when heated. They turn red in humid air. When heated or when concentrated hydrochloric acid, chloride, or organic solvents are added, its aqueous solution becomes blue. The compound crystallizes at 30–45°C and begins to weather, becoming turbid. It forms a tetrahydrate when heated at 45–50°C for 4 hours, and becomes anhydrous when heated to 110°C. It is obtained through the reaction of cobalt powder, cobalt oxide, cobalt hydroxide, or cobalt carbonate with hydrochloric acid.
物理的性質
Blue leaflets; turns pink in moist air; hygroscopic; the dihydrate is violet blue crystal; the hexahydrate is pink monoclinic crystal; density 3.36, 2.48 and 1.92 g/cm3 for anhydrous salt, dihydrate and hexahydrate, respectively; anhydrous salt melts at 740°C and vaporizes at 1,049°C; vapor pressure 60 torr at 801°C; the hexahydrate decomposes at 87°C; the anhydrous salt and the hydrates are all soluble in water, ethanol, acetone, and ether; the solubility of hydrates in water is greater than the anhydrous salt.
使用
Cobalt chloride (CoCl2) is used to manufacture vitamin B12, even though the compound
itself can cause damage to red blood cells. It is also used as a dye mordant (to fix the dye to
the textile so that it will not run). It is also of use in manufacturing solid lubricants, as an
additive to fertilizers, as a chemical reagent in laboratories, and as an absorbent in gas masks,
electroplating, and the manufacture of vitamin B12.
定義
ChEBI: Cobalt dichloride is a cobalt salt in which the cobalt metal is in the +2 oxidation state and the counter-anion is chloride. It is used as an indicator for water in desiccants. It has a role as a two-colour indicator, an allergen, a calcium channel blocker and a sensitiser. It is a cobalt salt and an inorganic chloride. It contains a cobalt(2+).
一般的な説明
Cobalt(II) chloride is an anhydrous cobalt salt. Cobalt(II) chloride participates in the synthesis of various esters in the presence of acetonitrile.
空気と水の反応
Hygroscopic. Soluble in water.
反応プロフィール
A 0.2 molar aqueous solution has a pH of 4.6. Cobalt chloride acts as a weakly acidic inorganic salt, which is soluble in water. The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases. These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid. They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible. Many of these compounds catalyze organic reactions. Potassium or sodium metals act to reduce metal halides, producing exothermic reactions, even explosions [Bretherick, 5th Ed., 1995].
危険性
May not be used in food products (FDA).
Can cause blood damage.
健康ハザード
Inhalation causes respiratory disease, shortness of breath, and coughing; permanent disability may occur. Ingestion causes pain, vomiting, and diarrhea. Contact causes irritation of eyes and may cause skin rash.
火災危険
Special Hazards of Combustion Products: Toxic cobalt oxide fumes may form in fire.
安全性プロファイル
Suspected carcinogen
with experimental carcinogenic data. Poison
experimentally by ingestion, skin contact,
intraperitoneal, intravenous, and
subcutaneous routes. Moderately toxic to
humans by ingestion. Human systemic
effects by ingestion: anorexia, goiter
(increased thyroid size), and weight loss.
Experimental teratogenic and reproductive
effects. Human mutation data reported.
Incompatible with metals (e.g., sodmm and
potassium). See also COBALT. When
heated to decomposition it emits toxic
fumes of Cl-.
純化方法
A saturated aqueous solution at room temperature is fractionally crystallised by standing overnight. The first half of the material that crystallises in this way is used in the next crystallisation. The process is repeated several times, water being removed in a dry-box using air filtered through glass wool and dried over CaCl2 [Hutchinson J Am Chem Soc 76 1022 1954]. It has also been crystallised from dilute aqueous HCl. The hexahydrate m 86o forms pink to red deliquescent crystals. It loses 4H2O on heating at 52-56o and forms the violet dihydrate which loses a further H2O at 100o to form the violet monohydrate which loses the last H2O at 120-140o to give the pale blue anhydrous deliquescent salt m 735o and b 1049o. A pink solution of CoCl2 in H2O becomes blue on heating to 50o or adding conc HCl which may precipitate the mono or dihydrate. The solid dihydrate gives a blue-purple solution with EtOH. Note: CoCl2 in H2O is a “sympathetic ink”, i.e. writing using an aqueous solution is almost invisible on paper, but becomes blue on warming the paper. On cooling or standing, the writing becomes invisible again. The anhydrous salt is soluble in H2O, EtOH, Et2O, Me2CO and pyridine. [Glemser in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II p 1515 1965.]
参考文献
M.K. Willkinson, et al., Phys. Rev., 133, 497 (1959).
塩化コバルト(II) 上流と下流の製品情報
原材料
準備製品
クロロチオりん酸ジメチル
水酸化コバルト(Ⅱ)
シリカゲル
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酢酸コレステロール
3-フェノキシベンズアルデヒド
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sodium [2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][1-[(2-hydroxy-4-nitrophenyl)azo]-2-naphtholato(2-)]cobaltate(1-)
炭酸コバルト(II)
ストレプトマイシン硫酸塩
C.I.アシッドイエロー116
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3,6-ジクロロ-2-メトキシ安息香酸 塩化物
Acid Yellow 128
LEATHERSPRAYINGBLUERL
ビタミンB12
ビス(2-エチルヘキサン酸)コバルト(II)
塩化コバルト(Ⅱ)
4-アミノ-1-ブタノール
Acid Red 213
1,2-ヘキサデカンジオール
チオりん酸O,O-ジメチルO-(3,5,6-トリクロロ-2-ピリジニル)
亜塩素酸ナトリウム
コバルト(II)オキシド
Ｏ，Ｏ－ジエチル－Ｏ－キノキサリン－２－イルホスホロチオアート
1,4-ヘキサジエン
ビス[2-[(4,5-ジヒドロ-3-メチル-5-オキソ-1-フェニル-1H-ピラゾール-4-イル)アゾ]ベンゾアト(2-)]-クロム酸(1-)塩