Sciencemadness Discussion Board

Sourcing Non-denatured Anhydrous Ethanol in the US?

FrozenSpool - 7-4-2023 at 00:18

Where is the best place to get fairly small amounts (~1L) of non-denatured anhydrous ethanol in the US? I can’t seem to find anything on eBay that is non-denatured. Has anyone ordered from LabDirect recently? I see they have non-denatured ethanol but read they were going out of business previously.

I need the ethanol to make sodium ethoxide, and therefore need it to be anhydrous. Would drying a spirit like Everclear with 3A molecular sieves produce sufficiently dry ethanol for this?

BromicAcid - 7-4-2023 at 04:14

It doesn't come up as often but there are different agents used for the denaturing of ethanol. Some ethanols are denatured with Methanol, others with Toluene, some with a mix of both. Some ethanols are simply denatured with denatonium benzoate. Point being there could be some denaturants that do not interfere with your desired synthesis.

Texium - 7-4-2023 at 06:02

Quote: Originally posted by FrozenSpool  
I need the ethanol to make sodium ethoxide, and therefore need it to be anhydrous. Would drying a spirit like Everclear with 3A molecular sieves produce sufficiently dry ethanol for this?
Yes, that will work. That would be my approach. Also, I think it was just an unsubstantiated rumor that LabDirect is going out of business.

Amos - 7-4-2023 at 07:02

If you look up perfumery-grade ethanol, the only thing they use to denature it is a small amount of tert-butanol, if I recall correctly. It's a unique situation that I don't think many people have explored the purification and use of, but I find it attractive for a lot of different uses of ethanol.

FrozenSpool - 7-4-2023 at 09:38

Quote: Originally posted by Texium  
Quote: Originally posted by FrozenSpool  
I need the ethanol to make sodium ethoxide, and therefore need it to be anhydrous. Would drying a spirit like Everclear with 3A molecular sieves produce sufficiently dry ethanol for this?
Yes, that will work. That would be my approach. Also, I think it was just an unsubstantiated rumor that LabDirect is going out of business.


Do any 3A sieves work? I had seen some things that ones off of eBay/Amazon are usually pretty crappy. Which is fine for my use case as long as it brings the concentration to ~99%.

hodges - 7-4-2023 at 11:08

Un-denatured, 99.8%: https://www.ebay.com/itm/204168520398

CharlieA - 7-4-2023 at 13:36

Undenatured grain alcohol (190 proof; 95%) is available at liquor stores.

Dr.Bob - 7-4-2023 at 14:35

You will either need an ATF exception letter to buy undenatured ethanol, or pay the $55/gallow tax on it. And few places sell anhydrous undenatured ethanol except to companies with ATF exemption. You may be able to find some denatured ethanol with acceptable denaturants, but hard to find it anhydrous. 3A sieves should work for drying it, as does very dry alumina. If you can buy small amounts from Lab Direct, that may be the best way forward.

AvBaeyer - 7-4-2023 at 15:15

I have purchased food grade 200 proof ethanol via Amazon. There are also distilleries that sell direct and can be located on google with the food grade search term. It is expensive as it is heavily taxed and minimum amount is typically 1 gallon. I use it in the lab as well as for limoncello. If you do buy it in plastic gallon bottles I suggest transferring to smaller glass bottles for storage.

AvB

esquizete_electrolysis - 9-4-2023 at 15:44

Since M.E.K. has slowly been phased out in my area and replaced with a substitute containing pure ethyl acetate (at least according to the SDS) I have gotten the idea of obtaining ethanol via hydrolysis. This wouldn’t be anhydrous and I haven’t tested it so it’s a pretty weak idea. I have noticed in some thrift stores they sell nearly pure ethanol in the form of hand sanitizer left over from Covid.

Sulaiman - 10-4-2023 at 04:32

Quote: Originally posted by FrozenSpool  

Do any 3A sieves work? I had seen some things that ones off of eBay/Amazon are usually pretty crappy. Which is fine for my use case as long as it brings the concentration to ~99%.

Cheap Chinese 3A sieves do produce >99%ABV
But
Mine had a lot of dust in with them.
The first use produced a cloudy suspension.
After recycling they gave no noticeable dust
and
Mine also absorbed/adsorbed quite a bit of ethanol
So (from memory) about 750ml of >99%ABV from a litre of >95%ABV
... but don't quote me.

PS one thing about my 3A sieves,
they do absorb about 15% w/w water
but they are not very dense so quite a large volume is required.
Like many, my goal was just anhydrous ethanol,
not efficiency,
So I poured alcohol into the sieves bottle to just cover the sieves.
Lots of sieves required, but easily recycled.
(wash with plenty of water to remove most alcohol before ovening)

My ethanol source was fractionally distilled fermented sugar

[Edited on 10-4-2023 by Sulaiman]

FrozenSpool - 20-4-2023 at 21:04

I ended up acquiring some sieves off eBay and used them successfully. I added an excess of sieves (about 1 cup) to 750 mL of commercially available 95% ethanol and let it sit for two days. I ended up at >99% on my hydrometer. There was some dust so in a last ditch effort I threw up a prayer and filtered through a coffee filter into a bottle, which didn't work. However, after another day, most of the dust had stuck to the bottom of the bottle which allowed me to pour out the ethanol to get it mostly dust-free. I might do that again or try to get ahold of some 3um filter paper to remove the rest.

The sieves did absorb some of the alcohol though. I ended up with around 550-600 mL.

[Edited on 21-4-2023 by FrozenSpool]

Keras - 21-4-2023 at 12:15

Try distilling E85. It is made with anhydrous ethanol (theoretically), since alcohol separates from petrol (sorry, gas) if it sucks in too much water.

E85 is cheap and widely available in the US.

It doesn’t matter if you have traces of alcanes in your distilled product, as they don’t react with sodium anyway.

ErgoloidMesylate - 4-5-2023 at 16:25

Quote: Originally posted by Sulaiman  


My ethanol source was fractionally distilled fermented sugar

[Edited on 10-4-2023 by Sulaiman]


Making your own alcohol is the low profile route.

Jenks - 5-5-2023 at 07:40

If you want a decent amount and have more time than money, the route I recommend is to buy the cheapest vodka you can find along with a pound of potassium carbonate. Use the potassium carbonate to remove water, and remove the water from the saturated potassium carbonate by evaporation before a fan on a hot plate. Repeat the drying with potassium carbonate until not all of it dissolves, by which time the ethanol should be about 95% with the remainder water. Remove the water with molecular seives, recycling them in a conventional oven at its top setting around 540F. An advantage of this route is that it gets around the obscure law in the US against distilling ethanol.

ErgoloidMesylate - 5-5-2023 at 11:28

Except you may not understand how insane big brother has become in the US.

Would you believe the govt may follow up on anyone who buys high% alcohol?

If not, and they are, you are fucked if they decide to enforce intrusion into your life at that point.