Re: ethyl alcohol

J. Wayde Allen 303-497-5871 (allen@boulder.nist.gov)
Tue, 10 Sep 1996 08:07:47 -0600 (MDT)

On Tue, 10 Sep 1996, David Morrish wrote:

> On Tue, 10 Sep 1996, Jack Fulton wrote:
>
> > <<<snip>>>.... I think that properly, the most common denatured alcohol
> > used in photography is called Methyl.

No! Denatured alcohol is ethyl alcohol (ethanol) that has been rendered
unfit to drink by the addition of some unwholesome substance, usually
methyl alcohol (methanol). In other words, denatured alcohol is a
mixture. The denaturing substance is usually chosen to make it difficult
to separate from the ethanol. Denaturing ethyl alcohol makes it possible
to sell it for commercial uses without having to worry about the liquor
laws.

> Excuse my ignorance if I'm wrong, but I thought not all alcohols are the
> same, safety-wise. If ethyl can be ingested "safely" (in moderation, of
> course ;-), methyl, on the other hand, is not just toxic when injested,
> but I thought it was also DANGEROUS to handle.

Methanol is not any more dangerous to handle than ethanol, but it is
poisonous to drink. Both are very flammable, and burn with an almost
invisible blue flame. Those flaming desserts that you get at the
restaurant use ethanol. The spirit lamps sometimes used in chemistry
labs and the kids old chemistry sets usually use methanol.

> (Unless, I'm confusing
> methyl hydrate with methyl alcohol, or are they the same?)

I'm not familiar with methyl hydrate, but I don't think it is the same as
methanol.

- Wayde
(allen@boulder.nist.gov)