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|Section8= }} Petroleum ether is the petroleum fraction consisting of C₅ and C₆ hydrocarbons and boiling in the range 35‒60 ℃; commonly used as a laboratory solvent. The term ''ether'' is used only figuratively, signifying extreme lightness and volatility. == Properties == The very lightest, most volatile liquid hydrocarbon solvents that can be bought from laboratory chemical suppliers may also be offered under the name petroleum ether. Petroleum ether consists mainly of C₅ and C₆ aliphatic hydrocarbons and is usually low on aromatics. It is commonly hydrodesulfurized and may be hydrogenated to reduce the amount of aromatic and other unsaturated hydrocarbons. Petroleum ether bears normally a descriptive suffix giving the boiling range. Thus, from the leading international laboratory chemicals suppliers it is possible to buy various petroleum ethers with boiling ranges such as 30‒50 ℃, 40‒60 ℃, 50‒70 ℃, 60‒80 ℃, etc. In the United States, laboratory grade aliphatic hydrocarbon solvents with boiling ranges as high as 100‒140 ℃ still appear to be called petroleum ether, rather than petroleum spirit. It is not advisable to employ a fraction with a wider boiling point range than 20 ℃, because of possible loss of the more volatile portion during its use in recrystallisation, etc. and consequent different solubility relations of the higher boiling residue. Most of the unsaturated hydrocarbons may be removed by shaking two or three times with 10 % of the volume of concentrated sulphuric acid; vigorous shaking is then continued with successive portions of a concentrated solution of potassium permanganate in 10 % sulphuric acid until the colour of the permanganate remains unchanged. The solvent is then thoroughly washed with water, dried over anhydrous calcium chloride, and distilled. If required perfectly dry, it should be allowed to stand over sodium wire.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Petroleum ether」の詳細全文を読む スポンサード リンク
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