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From: (Don Wilkins)
Newsgroups: rec.crafts.metalworking
Subject: Re: What's in "denatured" alcohol?
Date: Tue, 13 Oct 1998 03:31:39 GMT

On Mon, 12 Oct 1998 06:22:08 +0500, "David G. Michels"
<michels!> wrote:

>Victor Crecy wrote:
>> 95% ethanol, 5% methanol eh?  If a guy knew the boiling points for the
>> two he could probably distill some pretty potent shine out of it.

It is going to take a bit more than knowing the boiling points which
can be found in a chemical handbook but yes it would be potent (and
probably toxic).

> Hey, guess what. I work for the federal govt. I have had near 20 years
>working with oddball things like 'denatured' alcohol etc. I don't work
>for BATF, but have been through their regulations a number of times. I'm
>also a chemist.
> There are two kinds of dentaured alcohol. There is Specially denatured
>alcohol (including specially denatured rum) that is a mixture of alcohol
>with another ingredient that renders it un-drinkable. This type generally
>isn't poisonous depending upon the denaturant.

Close but no cigar. Yes there are two kinds of denatured ethanol.

But SDA (specially denatured alcohol) is treated with denaturants
which permit its use in a greater number of specialized arts and
industries. A SDA damned well might be poisonous and the most common
is SDA No 1 which contains methanol (wood alcohol). A SDA which has
been denatured for use for the synthesis of chemicals, antifreeze, or
fuel for example very well could be toxic.

Other denaturants are used which e.g. make it suitable in a mouth wash
or food flavorings but if you drink a whole bunch for the alcohol
content you are going to get sick enough so you won't do it again.

They use specific denaturants which will allow its use in various
endeavors but always under some kind of permit or bond.

>Examples are cinnamon oil, etc. SDA is used a lot in foods preparation
>where the company doesn't want the time and expense of using pure alcohol
>in a food product and being checked by agents all the time to ensure they
>are using it properly.
> The other kind of denatured alcohol is called completely denatured. This
>is the stuff that is denatured with gasoline, benzene, methanol, etc. It
>is produced in very large quantities, and the major use of this stuff is
>in your car as the oxygen-providing component in the winter time. At
>least where I live, anyway. CDA is a mixture known as a 'eutectic' mix.

As mentioned in another post "eutectic mix" is not the proper choice
of words.

CDA (Completely Denatured Alcohol) contains chemicals specified by the
US government (and other governments) which make it completely
unsuitable for human consumption and also are intended to make it
impossible to recover the alcohol from the mixture. (Note "intended")

There are some pretty obnoxious chemicals used in mixing CDA. E.g.
acetone, diethyl phthalate, ethyl acetate, gasoline, citronella
pyridine bases, soaps, wood alcohol,  brucine sulfate, etc. For the
non-chemists brucine is an alkaloid which will have a reaction in the
stomach comparable to strychnine. They do mean business when they say
unfit for human consumption.

Methyl isobutyl ketone and kerosine are the main ones now required by
the Feds

You will note that methanol (wood alcohol) is used in SDA as well as

> In physical chemistry that means that the components cannot be
>separated; at least, it cannot be done very easily. ( I remember working
>in the lab in graduate school, and we had a 5 foot spinning-band
>distillation column for solvent purification, and in a lot of instances
>that wouldn't remove the ethanol from the benzene). Having methanol and
>ethanol mixed together produce a similar result.
> The only 'fun' SDA mix I remember was the head of the chemicals
>stockroom used to mix ethanol with phenolphthalein-the stuff in 'ex lax'-
>to prevent any students having parties. And if they did, they paid for it
>when the ex lax did its job.

Hopefully that individual was caught and fired before he killed

From: (Don Wilkins)
Newsgroups: rec.crafts.metalworking
Subject: Re: Water break clean
Date: Fri, 08 Jan 1999 13:29:37 GMT

On Thu, 07 Jan 1999 08:18:54 -0500, Ted Edwards
<> wrote:

>Michael P. Henry wrote:
>> I'm not sure, but drug store isopropyl alcohol may contain some water
>> (ethanol typically contains about 5 % water, unless specially purchased).
>Ethanol forms an "aziotropic" mixture with water at 95%.  That is, when
>you heat it, the vapour and liquid both have the same composition.  It
>is therefore not possible to greater than 95% by simple distilation.

Actually all you need to do is add some benzene to the 95 % azeotropic
mixture and do a simple distillation. If this is intended for home
brew consider your chemistry limitations before proceeding but it will
give you absolute ethanol. Ain't chemistry wonderful?

> I don't believe Isopropyl has this property.

Isopropanol does not form an azeotropic mixture with water.

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