イソブタン 化学特性,用途語,生産方法
定義
本品は、次の化学式で表される炭化水素である。
解説
イソブタン，無色，特異臭をもつ気体．融点－159.60 ℃，沸点－11.73 ℃．容易に液化する．化学的には安定であるが，引火，爆発性がある．爆発範囲1.8～8.4体積％．液化石油ガスの成分として燃料に用いられるほか，オレフィンによりアルキル化されて，C6～C8 のイソパラフィン類(アルキレートガソリン)の製造原料，また脱水素によるイソブテン製造の原料に用いられる．
化粧品の成分用途
噴射剤、起泡剤
効能
噴霧剤
製造
イソブタン，脂肪族飽和炭化水素(アルカン)の一つ．分枝状パラフィンのもっとも簡単なもの．湿性天然ガス，石油系炭化水素の分解ガス中に含まれる．上記ガスより分離されるほかに，n-ブタンの異性化によっても生成される．構造は，プロパンの中心炭素と結合している水素の一つがメチル基と置換した形をとる．
化学的特性
2-Methylpropane (isobutane), C4H10, a flammable gas,
occurs in small quantities in natural gas and crude oil. It
has been detected in urban atmospheres at concentrations of
44–74 ppb. It also evolves from natural sources and
has been measured in diesel exhaust at 1.4–11 ppm
and in cigarette smoke at 10 ppm. The partition
coefficient of propane between olive oil and air at 37℃ is
12 using the method described by Sato and Nakajima and
Perbellini et al.. The lower explosive limit is
18,000 ppm in air.
使用
Isobutane occurs in petroleum, natural gas,and petroleum cracking products. It is usedas a fuel gas or a liquefied petroleum gas. Itis also used in organic synthesis.
定義
ChEBI: An alkane that is propane substituted by a methyl group at position 2.
一般的な説明
ISOBUTANE is a colorless gas with a faint petroleum-like odor. ISOBUTANE is shipped as a liquefied gas under its vapor pressure. Contact with the liquid can cause frostbite. ISOBUTANE is easily ignited. The vapors are heavier than air. Any leak can either be liquid or vapor. ISOBUTANE can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket.
空気と水の反応
Highly flammable.
反応プロフィール
ISOBUTANE is incompatible with the following: Strong oxidizers (e.g., nitrates & perchlorates), chlorine, fluorine, (nickel carbonyl + oxygen) .
危険性
Highly flammable, dangerous fire and
explosive risk; explosive limits in air 1.9–8.5%.
健康ハザード
Isobutane, like other saturated aliphatic alkanes,is nontoxic. It is an asphyxiate. Exposureto high concentrations of 1% in air maycause narcosis and drowsiness. Other thanthis, there is no report of any adverse healtheffect from exposure to this gas.
火災危険
EXTREMELY FLAMMABLE. Will be easily ignited by heat, sparks or flames. Will form explosive mixtures with air. Vapors from liquefied gas are initially heavier than air and spread along ground. CAUTION: Hydrogen (UN1049), Deuterium (UN1957), Hydrogen, refrigerated liquid (UN1966) and Methane (UN1971) are lighter than air and will rise. Hydrogen and Deuterium fires are difficult to detect since they burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.) Vapors may travel to source of ignition and flash back. Cylinders exposed to fire may vent and release flammable gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket.
安全性プロファイル
An asphyxiant. A
common air contaminant. A very dangerous
fire and explosion hazard when exposed to
heat, flame, or oxidizers. To fight fire, stop
flow of gas. When heated to decomposition
it emits acrid smoke and irritating fumes.
環境運命予測
Photolytic. Based upon a photooxidation rate constant of 2.34 x 10
-12 cm
3/molecule?sec with OH
radicals in summer daylight, the atmospheric lifetime is 59 h (Altshuller, 1991). At atmospheric
pressure and 300 K, Darnall et al. (1978) reported a rate constant of 2.52 x 10
-12 cm
3/molecule?sec
for the same reaction. Rate constants of 1.28 x 10
-9 and 6.03 x 10
-12 L/molecule?sec were reported
for the reaction of 2-methylpropane with OH radicals in air at 300 and 296 K, respectively
(Greiner, 1967, 1970). Rate constants of 7.38 x 10
-13 and 6.50 x 10
-17 cm
3/molecule?sec were
reported for the reaction of 2-methylpropane with OH and NO3, respectively (Sablji? and Güsten,
1990).
Chemical/Physical. Complete combustion in air produces carbon dioxide and water vapor. 2-
Methylpropane will not hydrolyze because it does not contain a hydrolyzable functional group.
純化方法
Olefins and moisture can be removed by passage at 65o through a bed of silica-alumina catalyst which has previously been evacuated at about 400o. Alternatively, water and CO2 can be removed by passage through P2O5, then asbestos impregnated with NaOH. Treatment with anhydrous AlBr3 at 0o then removes traces of olefins. Inert gases can be separated by freezing the isobutane at -195o and evacuating out the system. [Beilstein 1 IV 282.]
イソブタン 上流と下流の製品情報
原材料
準備製品
