DE36827C - Production of acetone-free methyl alcohol from raw wood spirit - Google Patents

Description

IMPERIAL

PATENT OFFICE

The previous method of preparing an acetone-free methyl alcohol consists in that. from the partly purified, crude methyl alcohol, which is mainly acetone contains, by mixing with calcium chloride separates a crystalline compound, which then freed from acetone by drying and decomposed again by distillation with water, which gives a pure, watery methyl alcohol, which on further treatment gives up Column apparatus respectively. Anhydrous distillation over lime is obtained. In whole In a pure state, methyl alcohol is also obtained by decomposing the oxalic acid methyl ether with potassium hydroxide. Finally, by distilling the raw wood spirit over lime, Cleaning with potassium hypermanganate, sulfuric acid and sodium hydroxide solution, as well as distillation Column apparatus also produce an almost pure methyl alcohol, which is almost exclusively Contains acetone as an impurity. The first two methods are extremely costly since the whole amount of methyl alcohol in connection with calcium chloride respectively. with oxalic acid is to be transferred and then decomposed again, while with the latter Method, even with the most careful work, the acetone content only down to 0.4 pCt. bring down is what still gives the product of sale an inferiority.

The present invention relates to a method by which the acetone content of the methyl alcohol is completely removed, and consists essentially in the fact that in purified and still acetone or even completely crude methyl alcohol is introduced with heating chlorine gas. The wood spirit will for this purpose it is best to remove the adhering acids by distillation with lime freed and the acetone content on the column apparatus to a low level (approx to 2 pct.). The so obtained acetone-containing methyl alcohol is with dry Chiorgas treated. This is best done by heating the methyl alcohol containing acetone up to the boiling point in a suitable vessel with reflux condenser, in which then dry chlorine gas is introduced. The same does not decompose the methyl alcohol, but only the acetone and from this forms the mono- and dichloroacetone, compounds, which at a much higher temperature than the methyl alcohol, 119 and 120 °, boil. From time to time a sample of the liquid is taken from the formed Chloracetones are distilled off and the distillate is examined for acetone by a known method. As soon as there is no longer any precipitate of iodoform, the introduction of chlorine is stopped. The methyl alcohol will then by fractional distillation of the. low-boiling chlorine substitution products formed of the acetone separated and purified from the last residues of adhering chlorine by distillation over lime.

In this way it is possible to produce a completely acetone-free methyl alcohol; the Any chloroacetone obtained can be converted back into acetone by suitable decomposition. This method of introducing chlorine can also be used with raw wood spirit, only then longer initiation is necessary;

but then at the same time other impurities are also destroyed by the chlorine the cleaning of the wood spirit is an easier one. The advantage of this method is in that not the whole mass of the methyl alcohol (98 to 99 pCt of the crude methyl alcohol) must be converted, isolated, and converted back into methyl alcohol, but that only the low acetone content, 1 to 2 pct., to move away remains.

Claims (1)

Patent claim: The production of acetone-free methyl alcohol by treating the pre-purified methyl alcohol that still contains acetone or the very crude methyl alcohol (possibly after it has been heated) with dry chlorine gas in order to convert the ^{acetone boiling at 58 0} into the chlorine substitution products of acetone boiling at 119 and 120 ° , and separation of the latter from the methyl alcohol.