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Torpedo juice: Legendary, illegal WWII liquor drunk in Alaska and the world

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Re: Torpedo juice: Legendary, illegal WWII liquor drunk in Alaska and the world

#91

Post by devilbunny »

hilbert42 wrote: post #88
devilbunny wrote: post #71

Earlier quoted context omitted.

Benzene really only shows up in traces if you're trying to get absolute ethanol (100%). You can distill up to 95% ethanol (the EtOH-water azeotrope) without introducing anything else.

Right, the EtOH/azeotrope is the normal domestic (industrial grade) product available where I am (Australia), it's available in all supermarkets, etc. That said, it often has impurities that ought not be present (see my other post). Here, 'absolute ethanol' is typically 99%. No doubt H2O is a significant part of that last 1% but going on my experience with 95% EtOH I wouldn't be a bit surprised about it being benzene…

Absolute ethanol in the US is a chemical product and does not have denatonium in it. It isn’t much used, but you will sometimes see it in chemistry labs for IR spectroscopy. It’s at least 99%, the whole point of it is having a solvent that wipes out that huge water absorption band on IR so you can see the rest.

Re: Torpedo juice: Legendary, illegal WWII liquor drunk in Alaska and the world

#92

Post by hilbert42 »

devilbunny wrote: post #91
hilbert42 wrote: post #88

Earlier quoted context omitted.

Right, the EtOH/azeotrope is the normal domestic (industrial grade) product available where I am (Australia), it's available in all supermarkets, etc. That said, it often has impurities that ought not be present (see my other post). Here, 'absolute ethanol' is typically 99%. No doubt H2O is a significant part of that last 1% but going on my experience with 95% EtOH I wouldn't be a bit surprised about it being benzene…

Absolute ethanol in the US is a chemical product and does not have denatonium in it. It isn’t much used, but you will sometimes see it in chemistry labs for IR spectroscopy. It’s at least 99%, the whole point of it is having a solvent that wipes out that huge water absorption band on IR so you can see the rest.

You'll note I've put absolute alcohol in quotes, here I'm referring to industrial/commercial grade 99% EtOH that's required in processes that cannot tolerate the 5% H2O such as in the application to which I've referred.

Clearly this grade should have denatonium added no matter where it's sold and I'm surprised that it's not readily available in the US. Moreover, there's no technical/chemical reason why denatonium shouldn't be added given that so little is need to be an effective bitterant. It seems to me the residual 1% 'impurities' would be much more relevant than the denatonium, even then, for most purposes, this 1% is already insignificant as far as the EtOH chemistry is concerned.

On the other hand as you note absolute ethanol as used as a reagent in precision experimentation (and in the pharmaceutical industry) would have to be devoid of denatonium. I'd add these grades usually come with a certified purity analysis/impurities percentage list together with the complying standard, BP grade, etc.

I'm unfamiliar with the regulations covering denaturants in the various countries but it seems to me the normal 99% grade with denatonium of the type I use is suitable for most purposes including most undergraduate lab chemistry (there's little point unnecessarily tempting students to imbibe).

Incidentally, when I was studying chemistry the denatonium option wasn't yet available so labs always had absolute EtOH available and the normal commercial denatured grade was roughly EtOH ~80%, MeO ~15%, pyridine ~5%.

I'm now curious as to how US-based woodworkers and painters manage using shellac if 99% denatured EtOH isn't readily available.

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