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METHYL ALCOHOL (CH3OH)
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METHYL See also:ALCOHOL (CH3OH) , the simplest aliphatic alcohol; an impure See also:form is known in See also:commerce as See also:wood-spirit, being produced in the destructive See also:distillation of wood. The name methyl, from Gr. 00u, See also:wine, 6Trt, wood, explains its origin. Discovered by See also:Boyle in 1661, it was first carefully studied by See also:Dumas and Peligot in 1831; its See also:synthesis from its elements (through methane and methyl chloride) was effected by See also:Berthelot in 1858. It is manufactured by distilling wood in See also:iron retorts at about 5oo° C., when an aqueous distillate, containing methyl alcohol, See also:acetone, acetic See also:acid and methyl acetic ester, is obtained. This is neutralized with See also:lime and redistilled in See also:order to remove the acetic acid. The distillate is treated with anhydrous See also:calcium chloride, the crystalline See also:compound formed with the alcohol being separated and decomposed by redistilling with See also:water. The aqueous product is then dehydrated with potash or lime. To obtain it perfectly pure the crude alcohol is combined h oxalic, benzoic or acetic acid, and the resulting ester separated`, purified, and finally decomposed with potash. Methyl alcohol is also obtained in the dry distillation of See also:molasses. The amount of methyl alcohol See also:present in wood spirit is determined by converting it into methyl iodide by acting with See also:phosphorus iodide; and the acetone by converting it into See also:iodoform by boiling with an alkaline See also:solution of See also:iodine in See also:potassium iodide; See also:ethyl alcohol is detected by giving See also:acetylene on See also:heating with concentrated sulphuric acid, methyl alcohol, under the same circumstances, giving methyl See also:ether. Pure methyl alcohol is a colourless See also:mobile liquid, boiling at 66°-67°, and having a specific gravity of o•8142 at o° C. It has a burning See also:taste, and generally a spirituous odour, but when absolutely pure it is said to be odourless. It mixes in all See also:pro-portions with water, alcohol and ether. Its compound with calcium chloride has the See also:formula CaC12.4CH3.OH, and with See also:barium See also:oxide BaO.2CH3OH. Oxidation gives formaldehyde, formic acid and carbonic acid; See also:chlorine and See also:bromine react, but less readily than with ethyl alcohol. The See also:chief See also:industrial applications are for making denatured alcohol (q.v.), and as a solvent, e.g. in See also:varnish manufacture; it is also used for a See also:fuel; a purer product is extensively used in the See also:colour and See also:fine chemical See also:industries. Methyl chloride CH,Cl, is a See also:gas, boiling at -23°, obtained by chlorinating methane, or better, from methyl alcohol; wood spirit is treated with See also:salt and sulphuric acid, or hydrochloric acid gas conducted into the boiling spirit in the presence of See also:zinc chloride, the evolved gas being washed with potash and dried by sulphuric acid. It is also prepared by heating trimethylamine hydrochloride. Alcohol dissolves 35 volumes and water 4. Methyl bromide is a liquid, specific gravity I•73, boiling point 13°; methyl iodide has a specific gravity of 2.19, and boils at 43°. Additional information and CommentsThere are no comments yet for this article.
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