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Is it safe to drink lab ethanol?

  1. Oct 22, 2004 #1
    I have been thinking about order 100% ethonal(^^OH) from a chemical supply on line. I know that i need to get undenatured/pure ethanol.

    What other kinds of contaiments way be present in ethanol (i.e. methanol?). Should i dilute it, I have had strong alchol before (151 proof).

    I know enough to no let me or any of my friends drink enough to get alchol posioning. Thanks for your time.
  2. jcsd
  3. Oct 23, 2004 #2


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    Please don't drink reagent grade ethanol...I can't see that any good can come from that.

    The primary impurity is methanol. If methanol concentration in your blood gets high, you will first suffer from nausea, vomiting and mild nervous damage including impaired vision. Consumption of about 10 ml of methanol will make you permanently blind. About 25 ml usually kills you.

    Even, pure ethanol, being lipid soluble, affect the normal working of membrane proteins by messing with cell membranes. Consuming any reasonable quantity of pure ethanol can cause acute ethanol poisoning. Acute ethanol poisoning may present with symptoms ranging from slurred speech, ataxia and incoordination to coma, potentially resulting in respiratory depression and death. At blood alcohol concentrations of greater than 250 mg% (250 mg% = 250 mg/dl = 2.5 g/L = 0.250%), the patient is usually at risk of coma.
  4. Oct 23, 2004 #3
    There is a reason why they don't sell lab grade ethanol to the general public.
  5. Oct 23, 2004 #4
    You should never drink lab grade ethanol. There are two main reasons one of which is technical and the other is so-called administrative...

    Technical is, you cannot have %100 grade ethanol to use in the lab. The major impurity methanol exhibits a azeotrope with the ethanol that is impossible to separate.

    So-called-administrative is that the commercially availible ethanol is denaturised with methanol. This is about taxes. Drinkable ethanol is taxes at the highest ratio (or very high; I am not sure about the rates). When it is denaturised, then this tax is decreased and it can be used as lab grade.

    If you really want to drink, then I recommend you to learn the fermantation of grapes to make "homemade" wine. Fermented alcohol will absolutely be much more safer ;) and making homemade drink is a nice hobby :)
  6. Oct 23, 2004 #5


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    Also technical grade ethanol contained pyridine as additional denaturizing agent in the past, in order not to be drunk (and as Mertas said, for tax-related purposes), but this treatment is not used much I think.
    Last edited: Oct 23, 2004
  7. Oct 23, 2004 #6


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    Home fermented alcohol might not be necessary safer if the proper sanitation and other steps are not done carefully. Brewing beer at home is one of my hobby. You get inexpensive alcohol (50 cents to 1 dollard a bottle, and that canadian money) at a reasonnable quality, better than most commercial breweries but not as good as some artisanal or micro-breweries. I also had to use the knowledge I acquire in my microbio degree.
  8. Oct 23, 2004 #7


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    Here's my question. Why? Why would you want to do such a thing?
  9. Oct 23, 2004 #8
    Beleive it or not one of the chemlab attendant was charged for drinking lab grade alcohol. Funny thing is they say he had been doing it for a long time until the teacher noticed that alcohol simply vanished. i read that u need 98 to 99% pure alcohol to drink. There could be an addition of methanol, pyridine,acetone and even formaline and some aldehydes.

    It is very dangerous to try and brew ur own alcohol at home as more than 50 people have died recently as the result of home made poisonous alcohol in my country. :cry:
  10. Oct 23, 2004 #9


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    I can be safe to brew your own alcoho at home but you have to follow strict guideline in order to have quality materials. I know people that have been brewing beer, wine and mead at home for over 20 years. However, I personnaly would not encourage people to try to recreate hard liquor because these process require a good knowledge of distillation and a good training in chemistry.
  11. Oct 23, 2004 #10
    Thanks for the warning

    I wasn't sure about the impurities. What if I were distill the ethanol out of vodka, or buy undenatured ethanol. I will be preforming distillation next week in lab. Thanks for your advice.
  12. Oct 23, 2004 #11
    Why don't you just put 20 dollars down on a bottle of everclear and see how you handle that? 190 proof. I doubt it'll be too fun though after you feel the burn.
  13. Oct 24, 2004 #12
    If it is only ethanol it is very good... I did Limoncello with that, but be careful that nobody has mixed with other sumstances!!!!!
  14. Oct 24, 2004 #13


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    I thought that the principle impurity in lab grade absolute ethanol was benzene. Trust me, you don't want to drink any benzene, no matter how small the amount.

    BTW, you'll never be able to get 100% ethanol by simple distillation. You have to use azeotropic additives, like benzene.
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