Sciencemadness Discussion Board

Where can I get relatively pure ethanol?

Electra - 29-3-2014 at 22:31

While I know it will be hard to get 100% due to moisture absorption, but is there any way to get clean ethanol in the USA? I have some reactions I want to run and denatured alcohol with methanol and whatever else they add into it will provide some very undesirable contaminants to my product that won't simply evaporate away. I would rather not have to distill anything.

Water in the ethanol is not an issue. I figured I could go down to the liquor store and pick up the highest concentration I can find, but do they even make alcohol without flavorings in it? My state doesn't sell Everclear to my knowledge.

I know for like $300 I could get a licenses to produce ethanol "fuel", but I am not sure if such a license is required for its purchase. Any suggestions?

Chemosynthesis - 29-3-2014 at 22:50

What volume of alcohol do you anticipate requiring?

PeeWee2000 - 29-3-2014 at 22:58

They usually have stuff that isnt purposley denatured, but often has trace chemicals to obtain the purity desired on ebay so still not good for any sort of food use but is quite pure.

http://www.ebay.com/itm/Spectrum-Ethyl-alcohol-Ethanol-absol...

numos - 29-3-2014 at 22:58

Try the pharmacy, you can usually buy 70% pure ethanol labeled as "ethyl alcohol" diluted with water

DraconicAcid - 29-3-2014 at 23:06

What reactions are you running? If it's just a solvent, isopropanol is often a good substitute.

Electra - 29-3-2014 at 23:19

Quantities under 1000ml to start, but could be more if I need it later. I do not need it just as a solvent. Additives such as Acetone, Isopropyl Alcohol, Methanol, or any other alcohols or carbonyls will hurt the purity of my final product.

Water content of the alcohol wouldn't matter since the final products easily separate from water, so my best bet may just be trying to find the highest grade I can get at the liquor store.

Chemosynthesis - 29-3-2014 at 23:22

I guess you should get vodka with the highest repetition of distillations on the bottle. I've seen five times distilled go for $17 at some places, since it was purchased in bulk from non-Russian countries.
Edit- that was earlier this year, too, in a US market. I'm assuming your geography is analogous.

[Edited on 30-3-2014 by Chemosynthesis]

Ethanol

essbee - 30-3-2014 at 03:21

Don't you guys have E85 bio gasoline? 85% dry ethanol and 15% gas. A good chemist could distil off the low bp 15% without causing a serious fire and be left with ~100% ethanol.

copperastic - 30-3-2014 at 04:03

If your over 21 you can buy some Ever clear . Its 95 percent ethanol.

Chemosynthesis - 30-3-2014 at 06:25

Quote: Originally posted by essbee  
Don't you guys have E85 bio gasoline? 85% dry ethanol and 15% gas. A good chemist could distil off the low bp 15% without causing a serious fire and be left with ~100% ethanol.

I doubt that would be as simple as that. Gas is so complex of a mixture I am pretty sure you will have azeotropes that would need to be broken with clever vacuum work, or liquid phase column chromatography.

Texium - 30-3-2014 at 07:11

Quote: Originally posted by numos  
Try the pharmacy, you can usually buy 70% pure ethanol labeled as "ethyl alcohol" diluted with water


I almost bought some of this 70% ethanol from Walgreens, but then I looked up the ingredients and found that along with being diluted with water, it had a ton of other stuff in it, making it not a viable option for any sort of lab use.

WGTR - 30-3-2014 at 11:01

Maybe you saw this useful thread recently:

https://www.sciencemadness.org/whisper/viewthread.php?tid=29...

Mixing this product here:

http://www.homedepot.com/p/Klean-Strip-1-Qt-M-E-K-Substitute...

with this product there:

http://www.lowes.com/pd_486650-331-HD-CRY-DO_0__?productId=4...

gives a useful mess of sodium acetate and ethanol. The ethanol can be simply distilled right out of the can according to
the method described in this video:

http://www.youtube.com/watch?v=DT35x-2aR6g

It does involve a distillation, albeit a simple one. A couple feet of refrigerator tubing pressed into the cap, with the can heated
gently in a warm water bath, might give the desired results.

My 2 cents....

annaandherdad - 30-3-2014 at 11:07

In California the liquor stores sell Everclear as a 75% alcohol/water mixture; in North Carolina (when I used to live there) Everclear was 95%. I don't know about other states. I've distilled the California Everclear to get a higher concentration. It's not super cheap, you pay a lot in taxes.

I have also distilled cheap wine to get alcohol. You could also brew your own.

Dr.Bob - 30-3-2014 at 11:55

You definitely need a license to buy ethanol for "fuel" that is not pre-mixed with gasoline or other nasties. If you only want small amounts, most liquor stores sell smaller bottles of relatively pure ethanol for flavor extractions and other uses, already taxed, but quite strong without flavoring. I have used such in the past, and know that some states allow that. Otherwise you will have to make your own, you could distill any of many sources, or even make your own starting material with sugar and yeast, it is easy to find directions on the internet for bioethanol, but it is not trivial to distill it, even to 95% purity. If it needs to be anhydrous, then it will be hard to get without work, or using denatured sources and purifying it, unless you can find an ATF license holder to buy it that way. That is a major pain as it is a government agency with little sense of humor or home science interest.

copperastic - 30-3-2014 at 11:57

Wisconsin has 95 percent.

numos - 30-3-2014 at 13:33

Quote: Originally posted by zts16  
Quote: Originally posted by numos  
Try the pharmacy, you can usually buy 70% pure ethanol labeled as "ethyl alcohol" diluted with water


I almost bought some of this 70% ethanol from Walgreens, but then I looked up the ingredients and found that along with being diluted with water, it had a ton of other stuff in it, making it not a viable option for any sort of lab use.


You're right, it does include some other ingredients :/ looks like I need a new source for ethanol. Although for cleaning it works great!

Steam - 30-3-2014 at 16:34

Try buying a bottle of 95% everclear, you could dry it using standard methods for alcohols.
Maybe you could distill it over sodium?

Zephyr - 30-3-2014 at 19:43

If you do not have access to Everclear and desire purity higher than 70%, I have bought 90% ethanol at a local hardware store. This is in Washington, but I think that if you want to purify it further, it is worth it to go the extra mile to get the 90% stuff as opposed to the 70% ethanol solution.
A method of drying simpler and safer than distillation over sodium would be to mix the alcohol with anhydrous magnesium sulfate.

essbee - 31-3-2014 at 04:28

Quote: Originally posted by Chemosynthesis  
Quote: Originally posted by essbee  
Don't you guys have E85 bio gasoline? 85% dry ethanol and 15% gas. A good chemist could distil off the low bp 15% without causing a serious fire and be left with ~100% ethanol.

I doubt that would be as simple as that. Gas is so complex of a mixture I am pretty sure you will have azeotropes that would need to be broken with clever vacuum work, or liquid phase column chromatography.


Well it worked fine for me, double distilling got rid of a very slight 'oily' smell and then I used the 'pure' ethanol for extractions and synthesis with no problems at all.....'pretty sure' there were no azotropic issues.



Chemosynthesis - 31-3-2014 at 05:50

Quote: Originally posted by essbee  

Well it worked fine for me, double distilling got rid of a very slight 'oily' smell and then I used the 'pure' ethanol for extractions and synthesis with no problems at all.....'pretty sure' there were no azotropic issues.


That is impressive. I would be slightly leery to distill gasoline without vacuum, preferably inert atmosphere. I'm glad that worked for your purposes, but unless you have spectra available (preferably clean NMR), I am extremely skeptical that your ethanol was what I would consider pure, especially if you only re-distilled once. I know I've had to rotovap, and sometimes flash chromatograph multiple times to get clean spectra from single reactions stages. The complexity of gasoline, if the OP seems concerned about denatured or possibly absolute alcohol, is what I consider extreme. Other alcohols in particular, which the OP is concerned about, can be present in at least a few percent in gasoline; for this reason alone, compounded by the addition of alkenes and lack of knowledge of the specific reaction(s) intended, I would be reluctant to suggest it without additional data indicating a grade or standard of extraction purity. The variation of gasoline compositions between states, seasons, and sometimes counties doesn't even ensure repeatable sampling.
http://www.afdc.energy.gov/fuels/ethanol_e85_specs.html

http://www.us.edu.pl/uniwersytet/jednostki/wydzialy/chemia/a...

http://www.atsdr.cdc.gov/toxprofiles/tp72-c3.pdf

edit meant re-distill, not distilled once.

[Edited on 31-3-2014 by Chemosynthesis]

Steam - 31-3-2014 at 05:59

If you can't go buy your own ethanol, you could just make your own!
Just look up "how to make moonshine"! ;)

zed - 8-4-2014 at 17:50

I have the impression that 190 proof (95%) ethanol is sold in Oregon State Liquor stores. I also have the impression, that it costs about 60 bucks a gallon. Used to be the federal tax was about 30 bucks a gallon. AND, the feds really do want their tax money. They are deadly serious about it.

http://www.oregonliquorsearch.com/servlet/FrontController?vi...

[Edited on 9-4-2014 by zed]

Texium - 9-4-2014 at 18:41

Texas has the 95% stuff. I don't understand why anybody would want to consume it, but I'm glad that they sell it, for the sake of chemistry.

Loptr - 15-4-2015 at 08:39

VA does not sell Everclear.

Magpie - 15-4-2015 at 10:13

A quote from an article about a Wisconsin lawmaker trying to ban Everclear:

"States that currently ban the sale of Everclear include California, Florida, Maine, Massachusetts, Hawaii, Iowa, Michigan, New York, Nevada, Ohio, Washington, North Carolina, New Hampshire and Minnesota."

If you live in one of the above states (except Hawaii) just take a field trip to an adjacent state that sells it. Field trips to obtain reagents are one of the exciting aspects of this hobby.

UnclearReactor - 15-4-2015 at 10:22

Buy the cheapest vodka you can find. Absorb the water with an anhydrous salt (e.g. Copper Sulfate, Magnesium Chloride). Distill gently with a water bath; you don't even need a condenser if the tubing is long enough.

Loptr - 15-4-2015 at 10:41

I just use denatured ethanol I get from the hardware store. The MSDS says that it contains both ethyl and methyl alcohol, along with methyl isobutyl ketone.

The ethanol and methanol have too close of a boiling point to effectively separate, but the methyl isobutyl ketone has a boiling point of 117.5C, so it can be separated using fractional distillation since that is a 39.5 degree difference.

I don't mind methanol being a minor constituent, and if I wanted to, I could just remove the MIBK.

EDIT: What I do hate though is when the MSDS says that denatured ethanol could be anywhere from 0 to 50% methanol. You could take some measurements and figure out how much methanol was there, but the lack of a guarantee that you are actually being ethanol irks me.

[Edited on 15-4-2015 by Loptr]

Dr.Bob - 15-4-2015 at 11:18

There is a guide (google the web to find it) to specially denatured alcohols that tells what the law says must be in each one. So if the MSDS says which SD it is (eg, SD 42), you can see what the level of MeOH is by law. In many states you can buy 95% EtOH in liquor stores as long as you don't mind paying the tax, which is a lot. I know one person who used to do that. You might have to ask for it, maybe say that you wish to make some extracts for flavoring agents or something. All the state cares about is that you pay the taxes, most of the time.

Ephesians - 15-4-2015 at 17:03

I have 4 liters of reagent grade ethyl alcohol available from Fischer scientific if you are interested

gdflp - 15-4-2015 at 17:10

Quote: Originally posted by Steam  
Try buying a bottle of 95% everclear, you could dry it using standard methods for alcohols.
Maybe you could distill it over sodium?


I know this post is over a year old, I just didn't want any viewers to be misinformed. Although this is standard practice for some solvents, it won't work as well with with ethanol because ethanol reacts rather vigorously with sodium to form sodium ethoxide.

thanos thanatos - 17-4-2015 at 20:31

Quote: Originally posted by gdflp  
Quote: Originally posted by Steam  
Try buying a bottle of 95% everclear, you could dry it using standard methods for alcohols.
Maybe you could distill it over sodium?


I know this post is over a year old, I just didn't want any viewers to be misinformed. Although this is standard practice for some solvents, it won't work as well with with ethanol because ethanol reacts rather vigorously with sodium to form sodium ethoxide.


Use 3A molecular sieves.

Zombie - 17-4-2015 at 20:44

Period.

Buy Ever-clear, and follow the above post.

It doesn't get any better than that.

You have to purge with nitrogen to store for long periods but you also have to purge to use it if you want 99% +

adk - 20-4-2015 at 19:40

Well, there are a few options for pure ethanol;

1. Go to a laboratory supplier and buy "absolute ethanol". Where I live (Australia) one must obtain a permit to obtain alcohol that has not been denatured. There is no problem in buying absolute ethanol that has been denatured (typically with denatonium benzoate/Bitrex). Denatured alcohol is therefore not suitable for use in any application where the end product may be consumed.
Cost: $20-30 / 2.5L bottle

2. Go to a liquor shop and buy high proof alcohol or rectified spirit. Here in Australia, this product is typically available as a product called "Spirytus", a Polish grain alcohol. It is 95% v/v ethanol and not denatured. You will need to use 3A molecular sieves and distillation to remove the last bit of water. Cost - $60-70/500ml - expensive but very useful for products that may be consumed later. I use it for extracting lemon oils in order to make Limoncello. Potent but tasty

3. Ferment your own alcohol from grain and distill using fractional distillation. You may need to distill twice or three times to get the constant boiling azeotrope which is also 95% ethanol. A little more difficult but in the long term it may be cheaper, depending on where you live.

4. Distill cheap & nasty white spirits. You can buy cheap vodka and distill it using very simple laboratory glassware. Recommend using a 1 or 2 litre flask, 200-300mm insulated fractioning column and efficient condenser to obtain a good yield of alcohol. May be cheaper than buying rectified spirit but risk of contamination from alcohol congers significantly increased if you use a spirit other than vodka.

Magpie - 20-4-2015 at 20:36

I buy Everclear (95%), distill it over CaO (burnt lime), then treat with 3A mole sieves. This has been suitable for some very finicky syntheses. See Vogel.

I don't see why you couldn't skip the burnt lime and go right to the mole sieves. Seems like I tried it and it didn't work as well.

I make my burnt lime by firing hydrated lime, Ca(OH)2, aka slaked lime. This is available dirt cheap by the pound at your neighborhood weed & feed store. Bring your own container or plastic bag.

adk - 21-4-2015 at 19:18

Well, there are a few options for pure ethanol;

1. Go to a laboratory supplier and buy "absolute ethanol". Where I live (Australia) one must obtain a permit to obtain alcohol that has not been denatured. There is no problem in buying absolute ethanol that has been denatured (typically with denatonium benzoate/Bitrex). Denatured alcohol is therefore not suitable for use in any application where the end product may be consumed.
Cost: $20-30 / 2.5L bottle

2. Go to a liquor shop and buy high proof alcohol or rectified spirit. Here in Australia, this product is typically available as a product called "Spirytus", a Polish grain alcohol. It is 95% v/v ethanol and not denatured. You will need to use 3A molecular sieves and distillation to remove the last bit of water. Cost - $60-70/500ml - expensive but very useful for products that may be consumed later. I use it for extracting lemon oils in order to make Limoncello. Potent but tasty

3. Ferment your own alcohol from grain and distill using fractional distillation. You may need to distill twice or three times to get the constant boiling azeotrope which is also 95% ethanol. A little more difficult but in the long term it may be cheaper, depending on where you live.

4. Distill cheap & nasty white spirits. You can buy cheap vodka and distill it using very simple laboratory glassware. Recommend using a 1 or 2 litre flask, 200-300mm insulated fractioning column and efficient condenser to obtain a good yield of alcohol. May be cheaper than buying rectified spirit but risk of contamination from alcohol congers significantly increased if you use a spirit other than vodka.

TonyZ - 11-6-2015 at 13:40

Quote: Originally posted by Magpie  
I buy Everclear (95%), distill it over CaO (burnt lime), then treat with 3A mole sieves. This has been suitable for some very finicky syntheses. See Vogel.

I don't see why you couldn't skip the burnt lime and go right to the mole sieves. Seems like I tried it and it didn't work as well.


Are you saying that when you tried directly treating Everclear (95%) with 3A mole sieves, it didnt work well? Meaning it didnt dry the everclear well? or didnt work well in some syntheses?

From what I read, static drying of 95% ethanol can be done with 3A sieves. I attached one of the papers.

Here are a few of them.
J. Chem. Tech. Biotechnol. 1984, 34A, 187-194 (static and column drying of 95% ethanol)
*J. Org. Chem., Vol. 48, No. 14, 1983

Thanks
TonyZ

* I noticed in an older thread, you referenced this paper regarding drying ethanol (which contains 1500ppm (0.15%) water).

Attachment: J. Chem. Tech. Biotechnol. 1984, 34A, 187-194.pdf (466kB)
This file has been downloaded 1665 times

[Edited on 11-6-2015 by TonyZ]

[Edited on 11-6-2015 by TonyZ]

Magpie - 11-6-2015 at 14:43

Quote: Originally posted by TonyZ  

Are you saying that when you tried directly treating Everclear (95%) with 3A mole sieves, it didnt work well? Meaning it didnt dry the everclear well? or didnt work well in some syntheses?


I'm sorry but I can't remember.

IIRC, CaO will take the water down to 1%. So, if you use CaO first you reduce the load on the sieves by about 80%.

binbin - 11-6-2015 at 17:27

It is so easy to ferment and distil your own alcohol. Sugar, water, yeast, a glass bottle, a vent top, and 5-6 days. Distil after fermentation is complete.. 95.6% ethanol if you have a good column and condenser.

Molecular Manipulations - 11-6-2015 at 20:09

Easy? Sure. Practical? Not really. Legal? Almost certainly not, even if you can prove you didn't drink it.
I've done this a few times, and found it to be a big pain.
The most recent time I used turbo yeast, capable of withstanding alcohol percentages of up 18%. Let it ferment at room temperature for a week (twice as long as the package suggested). Distilled twice normally and then once with magnesium sulfate (I didn't need it to be more than 95%, otherwise I'd of used a stronger desiccant).
Overall time took a week and a day, the week doing nothing but the last day I spent about six hours monitoring several distillations. Yield was one liter of not very pure ethanol, containing at least 4% water and many trace organic impurities.
I could have gone to work that day and earned enough money to buy five liters of vodka (40%) or about one to two liters of everclear (95%).
The only application I can think of this being useful is for those who can't legally buy ethanol (because of either country, or age restrictions). However this is very, very rare these'a days. I had friends who bought me liquor to drink at age 14, and my parents would've done it if it was for chemistry purposes.
Regarding countries where it's illegal, I'm sure they have denatured alcohol, which works most of the time. Oddly I wasn't able to buy denatured alcohol under age either, probably because they think teens are really dumb and might drink it and die, (I wasn't planning on drinking it, I had in molotov cocktails in mind:P, turned out gasoline works fine though).