Committee on the Separation of Methyl, or Wood Spirits, from Ethyl Alcohol, 1882

The National Academy of Sciences’ Committee on the Separation of Methyl, or Wood Spirits, from Ethyl Alcohol, 1882

The reasons for which the advice of the Academy was desired on this subject are very clearly and fully stated in a letter which the Commissioner of Internal Revenue, Green B. Raum, addressed to the President on April 12, 1882. He writes:

“There is now pending before Congress a bill (H. R. 5082) ‘To authorize the withdrawal from distillery warehouse, without tax, of alcohol and other spirits to be used in industrial pursuits,’ which bill provides that ‘such spirits shall either first have been mixed with one-ninth of their bulk of methyl, or wood alcohol, of equal proof strength, or that such spirits shall be withdrawn for use in tobacco factories, or such other industrial pursuits as shall entail their complete destruction so that they cannot be recovered by any process of distillation.’

“It is therefore deemed important to the interests of the revenue that a careful and thorough investigation be made, having for its object the determination of the fact whether the methyl, or wood spirits may be entirely, or approximately, separated by distillation, or in any other economical manner from the ethyl alcohol, or spirits of wine, upon which the tax is imposed.

“In other words, the information sought is as to whether the science of chemistry now enables the possessor of the methylated spirits to separate the ethyl alcohol from such mixture in such a state of purity, and at such a probably cost as might enable the holder to sell it in the market at a less price than those persons who withdraw spirits from bond upon payment of the tax at the rate of ninety cents per proof gallon.

“I have therefore to respectfully request that a committee of the National Academy of Sciences be appointed to undertake this investigation, and to inform this office of the result at the earliest moment practicable.

“I desire particularly to be advised as to the relative vaporizing point of purified wood-naphtha as compared with distilled spirits of the same specific gravity, and such other information on the subject as may assist this Office in reaching a conclusion as to whether or not the bill referred to would be liable to abuse if it should become law.

“I have to ask if it is the pleasure of the academy to undertake this investigation, and if so to be informed as to the nature and quantity of alcohol, wood-naphtha, and other materials which will be needed in the prosecution of this inquiry.” [Rep. Nat. Acad. Sci. for 1883, pp. 57, 58.]

The Acting President, Prof. O. C. Marsh, appointed a committee consisting of Ira Remsen, G. F. Barker and C. F. Chandler which reported on September 18, 1882. The report covered various aspects of the question at issue. It began by pointing out that in both England and Germany the law had for a number of years permitted the use of methylated spirits in the arts, and gave a resume of the reports of the committees on which the legislation was based. It then defined the several liquids known as ethyl alcohol, methyl alcohol, crude wood-naphtha, and refined wood-naphtha or wood spirits, and described a number of experiments made by the committee with mixtures of ethyl alcohol and refined wood-naphtha. The committee summed up its report as follows:

“The final conclusion to which we are led is this: That by treating the mixture of ethyl alcohol and wood spirits (in the proportion proposed in the bill now before Congress) with bone-black, filtering, adding a caustic alkali—as, for example, caustic potash—and then distilling with the aid of the Hempel tube, the principal product obtained is nearly free from methyl alcohol, and that the odor and taste of this product are not very marked. At the same time, even in the best product thus obtained, the odor and taste characteristic of wood-naphtha can be detected, though only with difficulty, by those who are unskilled in such matters. We believe that the method employed by us which gave the best product could be applied economically on the large scale, and a product fully as good as our best, if not better than it, might thus be obtained.

“As regards the question whether the product obtained could be used for drinking purposes, that is difficult for the committee to answer satisfactorily. We have submitted our best specimens to some well-known dealers in alcohol and alcoholic beverages, and we learn that the purified product might easily be used in the manufacture of low-grade whiskies and rum, though all the gentlemen whom we have consulted on this point have unhesitatingly recognized the presence of the wood-naphtha in the best specimens.

“It would appear from this that, while after the addition of the wood-naphtha to alcohol, it is extremely difficult, if not impossible, to separate the two perfectly and thus regenerate the pure alcohol, it is quite possible to get from the mixture a product which might be used in the manufacture of alcoholic beverages of lower order.

“It is plain from the foregoing that, considering our experiments as final, it is impossible to purify the mixture containing wood-naphtha to a sufficient extent to make it palatable without the aid of distillation. Hence, apparently, it would be as difficult to carry on the process of purification on the large scale as to carry on the illegitimate manufacture of alcohol. This fact, in itself, might be a sufficient protection against fraud, though the committee does not feel competent to express a decided opinion on this point.” [Rep. Nat. Acad. Sci. for 1883, pp. 62, 63.]