I got to thinking about grain alcohol today (as we all should from time to time), and I realized that the proof showing on a bottle of Everclear is only 198. I’m pretty sure that Everclear is the closest to “pure” alcohol commonly commercially available. Is it possible to distill a liquor to 200 proof or is 198 the limit?
It’s possible to get it, but it won’t be drinkable.
From here
Alright, that makes sense, and I think that I even get the science behind it. How then is it that Everclear is brought 8 proof over what that mentions as the maximum?
and the point of drinking ethanol would be what, exactly?
That’s a question that’s been asked for centuries…
In addition to producing it in the first place, there’s difficulties in keeping it that way. Ethanol is hygroscopic, that is, it absorbs water from the air. You would have to be careful how you handled it during packaging to avoid picking up a bit of water from anywhere in the system, and even if you got it safely sealed in a bottle for sale, it wouldn’t stay 100% pure once opened. For the purposes of consumption, products like Everclear can essentially be regarded as pure alcohol.
It isn’t. The manufacturer’s web site lists the strongest Everclear sold at 190 proof.
The azetropic problems also explains why you get 190 proof lab ethanol by the gallon but 200 proof lab ethanol by the pint. Though I can’t think of any time I’ve ever needed pure ethanol as either a solvent or a reagant.
What if you used the method mentioned below to get 200 proof and then used one of these alcohol vaporizing machines to inhale it?
Everclear is 95% alcohol and 5% water, the highest possible alcohol content possible by distilation, as Number explained. This is 190 proof in the US system. It’s possible that a different way of measuring the alcohol content results in a ‘198 proof’ designation. Everclear is also available in a 151 proof form (probably to allow its sale in places where 151 proof is the maximum legal alcohol content), but it is not available in a 99% alcohol (198 proof, in the normal US system) form as far as I can tell. 99% alcohol is possible, but would require chemical treatment, and thus would be much more expensive.
asterion: I remember using both 95% ethanol and absolute ethanol quite a few times. You’d need absolute ethanol for a reaction that would fail if water was present, such as a Grignard reaction. I can’t remember whether the absolute ethanol was in an ordinary bottle or the type with a rubber septum (where you keep the liquid under nitrogen to avoid contact with air). If the ethanol was to be used as a reagent, a septum bottle would be more appropriate.
Well, yeah, I know there are times when you’d need pure, clean ethanol. But I’ve never done a Grignard reaction, for example.
100% ethanol (200 proof) is used to dehydrate (and rehydrate) tissues, as part of many protocols for stainings. Also, I’ve seen 100% and 95% both in gallons, not pints. Unless you mean the cost (ie, a gallon of 95% is worth the same as a pint of 100%).
Depending on how strict they are following the protocols, some labs may use 95% instead of a 100% in dilutions.
I remember in my Organic Chem lab there was a 5 gallon container of absolute ethanol. I remember thinking how cool it would be to have it at a party: “Here, let me fix you a real drink.”
But then, I was an idiot when I was 21.
We had absolute ethanol at one of my labs. It had state liquor control stamps on it. I bought it for work with crystals. According to persistent rumor, someone once took some of the stuff back to his office to drink and got seriously ill. They found him with a purple face. Why would you waqnt to drink it?
Back n high school we’d fermented a yeast and sugar water mix and disytilled the result. We calculated it was about 180 proof. It tasted awful.
Many molecular biology protocols call for 200 proof ethanol for precipitating DNA. We used to use it all the time in large scale plasmid preps. As far as I know 190 proof will work just as well in this application, but I think there is a persistent belief that the 200 proof is cleaner and gives you a purer final prep.
A couple of idiots I went to college with stole some of that 200 proof from the chemistry lab and spiked the punch with it at a dorm party. As far as I know no one got sick (well, no sicker than usual, anyway). Presumably it was diluted enough.
When I spent my formative years in the chemical stockroom at a pharmaceutical company, I enjoyed providing pure 200 proof alcohol to the scientists.
The stuff was labeled “200 proof, punctilious”, which this site says is the absolute pure unadulterated article.
Originally, the scientists would belly up to the counter with a pint flask and we would whip out a brown gallon jug of the stuff and a funnel and fill their flask. They had to sign the alcohol log.
A few years later someone probably realized that the alcohol really ceased to be 200 proof the first time we cracked the seal for the first customer, so they started buying it in one-pint flasks – clear round bottles. Another year or so later, the manufacturer started shipping it in small flat plastic bottles that bore a strong resemblance to hip flasks.
Of course, every scientist had a story to tell about the stuff, and considering that it had no nasties in it, it wouldn’t surprise me if at least one of them was telling the truth.
Ours didn’t have liquor tax stamps on it, though we did maintain a strict inventory. I suppose the company had a tax exempt license (as described by the link above)
You’re kidding, right? 
In ethanol distillations for purposes of gasoline additives, a purity of > 99% is required. Modern distillations use molecular sieves to extract the water from the 95% mixture. So you won’t get extra chemicals from a chemically broken azeotrope.
I think the real reason you don’t have 99%+ everclear is that there would be a lot of extra expense, and you can only increase the amount of alcohol 5% at most.
It’s only 190, as somebody else said. Next time, look at the label before you start drinking. 
I recall in my younger, stupid, drinking days we used to drink a bottled concoction named, “Wilson’s: That’s All.”
I haven’t googled it yet to see what history says, but as I recall it was advertised as 200 proof.
FWIW (hic!) N a S t Y stuff, whoo!