diluiting ethanol to make 10%

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Erm I more interested in knowing what the remaining 4% of the ethanol is.:eek:

I suspect it will be methanol which is poisonous and added to ethanol to stop people drinking it. If you are going to consume your concoction, be prepared to end up in hospital (or a morgue).

Seriously, lab grade ethanol is poisoned that is used in lab to stop people drinking (for Customs and Excise tax reasons).

Now the tale I heard about the chemical company that was mistakenly supplied with a tanker pure ethanol instead of lab grade is quite amusing, with people smuggling out gallons of he stuff before Customs and Excise turned up on the door step....
 
Caporegime
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Not really, lab grade ethanol is often exceptionally pure. You can't do chemistry without pure ingredients. The 4% is likely to be water.

I have a bottle of 90% ethanol used for cooking. several kilos of sliced lemos and bags of sugar go in - a month later limoncello comes out....
 

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Not really, lab grade ethanol is often exceptionally pure. You can't do chemistry without pure ingredients. The 4% is likely to be water.

I have a bottle of 90% ethanol used for cooking. several kilos of sliced lemos and bags of sugar go in - a month later limoncello comes out....

It will only be pure if you've paid a lot of duty to HM customs.

Basically lab grade (made non drinkable) = low tax.

Drinkable = extortionate tax and HM customs will be VERY interested in what you are doing with it.

Have a look here for more discussion.

http://www.physicsforums.com/archive/index.php/t-49176.html
 
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Not really, lab grade ethanol is often exceptionally pure.
You can't get pure ethanol. Not without ££££.

It's hygroscopic - it will readily absorb water from the atmosphere.

Most in labs, including ours, will be 90-99.5%. You can get 200proof, e.g. for purification and precipitations, but it's double the cost and smaller volumes - and will still contain methanol in traces.
 
Caporegime
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Seriously, lab grade ethanol is poisoned that is used in lab to stop people drinking (for Customs and Excise tax reasons).
.

no it isn't.

cleaning ethanol is, "lab grade" (especially analytical grade) is 99% or if lower the reminder is water, if methanol was in it it would interfere with a great number of experiments.

odds are the op's ethanol contains only water as getting that last 4% out will put the price up needlessly.

iirc labs can be exempt from the dtuy if they prove it;s not for drinking.
 
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Man of Honour
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Lots of people wandering around close to the correct answer...



"Lab grade" ethanol is actually several different grades, with the best-known descriptors being the old Merck ones: Analar, GPR etc. All are about 96% ethanol and 4% water - as meghatronic says, ethanol will absorb water from the atmosphere. It is possible to get less water, but it has to be stored under nitrogen etc. What divides the various grades is the exact amount of various other impurities. This does include methanol, but this is at very low levels (<0.001% IIRC) in every grade.

As a result, lab ethanol is perfectly safe to drink as long as you dilute the stuff. HMRC therefore make every lab that has a licence to possess ethanol account for every drop they use. One of the many annoyances of becoming a GOC was that we were no longer covered by the Home Office exemption, and now we have to fill out a log book every time we take some out of the winchester.


M
 
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