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Wildfire
01-20-2019, 11:04 PM
Here is a good question. I bought some dirty ethanol from my local store (bioflame ethanol). It says: contains 99% pure ethanol. So I am guessing that 1% must be congeners and other additives to keep it from being used as a drink. It comes up as 96% alcohol on my hydrometer. I have used 3A molecular sieves to (dry) the alcohol to 100%. Now the actual question. After having dried the alcohol would it be possible to use my fractional still to accurately separate the ethanol from the congerners? I am assuming that it is possible as the azeotrope is gone. What do you guys think?

May your lab remain intact

elixirmixer
01-20-2019, 11:11 PM
This basically all depends on what type of additives they are using, and, if its anything like it is in my country, there is no legal obligation for them to tell you what it is, so the only real way to know is to try it out.

:)

Aham
01-21-2019, 01:47 AM
Here is a good question. I bought some dirty ethanol from my local store (bioflame ethanol). It says: contains 99% pure ethanol. So I am guessing that 1% must be congeners and other additives to keep it from being used as a drink. It comes up as 96% alcohol on my hydrometer. I have used 3A molecular sieves to (dry) the alcohol to 100%. Now the actual question. After having dried the alcohol would it be possible to use my fractional still to accurately separate the ethanol from the congerners? I am assuming that it is possible as the azeotrope is gone. What do you guys think?

May your lab remain intact

Personally, I would not use "dirty ethanol" since it's hard to know how much methanol is present... Just my $0.02.

Wildfire
01-21-2019, 01:49 AM
You nailed it right on. So the only way I can really do it is by watching the thermometer on my still and do a smell, taste, burn test in the end. ethanol evaporates around 78C. I am not aware of anything that can be added to ethanol that would also distill at such a temperature, but I will try that. Thanks elixir mixer :)
May your lab remain intact

Wildfire
01-21-2019, 01:51 AM
Oh man... I tried doing the sugar wash thingy but it is sooooo lonnngggg lol. I thought of cheating it a bit and buying fireplace ethanol fuel. With some luck I'll be able to distill it. rectification is fun and relatively quick, but fermenting... I'm growing a white beard just thinking about it. Thanks though bro ;)

elixirmixer
01-21-2019, 03:01 AM
Methanol can be easily removed with a fractionating column or even a normal distillation.

Simply and slowly distill off the first 5%. making sure to bring it up to boil nice and slowly. Discard that 5% as it is a neuro-toxin and can make you "blind drunk" Literally; by dissolving the nerves that attach your eyes to your brain.

Ironically, the only cure for methanol poisoning is, ethanol poisoning. So If you do get a high exposure to methanol accidentally (as some of us have) simply get really drunk on the rest of your brew.

Mmmm Mmmm scrumptious. :D

Wildfire
01-21-2019, 03:12 AM
Thank you bro good info there :)

Wildfire
01-21-2019, 03:16 AM
I did an initial distillation on it and filtered it with activated charcoal then afterwards a second distillation. In the end it wreaked of acetone like smell and when I burned a bit of it the flame was mostly blue with some yellow and there was some residual acetone like smell in the spoon after it flamed out.

elixirmixer
01-21-2019, 05:34 AM
Pure ethonal does tend to have a strong smell. Blue flames are perfectly normal for spirits.

The true test (assuming you have already removed the methanol) is to dilute it;
40% spirits
60% water

Pour 30mls of your 40% solution into a glass, add orange juice and some red cordial and have a sip. If its rather nice, then you've successfully removed the bittering agent. If it still tastes bitter as your mothers temper, than you have failed.

If in doubt about the methanol than distill again, and remove 10% instead of 5. Very simple really, there is only 1 or 2% methanol to begin with so even 5 is being pretty cautious. (methanols boiling temp is a far bit lower than ethanol and thus distills over first if done gently.)

Enjoy :cool:

Wildfire
01-27-2019, 11:32 AM
Ok guys I have figured out exactly how to purify the store bought alcohol. Dear Lord I almost died of frustration, but alas it is done.
1. You must do a primary distillation with a vigreux column IF the starting alcohol is not 96.5% alcohol or around this mark.
2. dry magnesium sulfate to its anhydrous state. Put Epson salts into a stainless steel pot and heat it until it becomes chalky dry. You can find many YouTube videos about this. For the least amount of work I would suggest just leaving it in the pot while drying with minimal disturbing. No matter how much stirring you do, it will become a gooey sticky mess and you will have to break it up in the end anyhow. So better let it dry on highest heat until there is no more water.
3. Use a mortar and pestle to grind the chalky bulky salts (DO NOT USE A COFFEE GRINDER!) if you use a coffee grinder the powder will ruin your grinder and the mortar and pestle can do a reasonably good job as well with little effort.
4. Make sure that your distillation apparatus is clean, dry and has no visible moisture in it. Grease all joints with Vaseline or your choice of grease and make sure it is air tight as you don't want air coming into this setup.
5. As soon as your salts are ground and still warm, transfer then into the distillation flask and immediately add the alcohol to be distilled.
6. Attach a small tube hose to the vacuum outlet of the apparatus and put the tip of the other end into an oil jar. The reason for this is that this process produces positive pressure and it is a relief for that pressure without letting air back into the setup.
7. Start the distillation and keep and eye on your thermometer. whatever comes over below 78C is garbage as it contains all sorts of denaturing agents. pure anhydrous ethanol will distill at 78.37C and you can distill until maybe 82C. I got just pure stuff until the end as there was no tails in my store bought stuff ;)

The tests:
1. Smell test: Pure ethanol does not smell like anything. If it does you probably and most likely have acetone in it (nail polish remover)
2. Burn test: Put a few drops of it on a spoon and light it on fire. The flame should be blue and NOT yellow. Once it burns you can smell the spoon. If it smells like vinegar you know you have acetone present (in my opinion this is one of the best tests!)
3. Taste test: Pure alcohol does not have any taste. I wouldn't taste this stuff until at least a 3rd distillation is done and you cannot smell any vinegar on your spoon. Even so just one drop guys. lol

I would suggest that you distill the alcohol 3 times to get as pure a product as possible and each time using the Epson salts as a desiccant agent.
May your labs remain redundant!

Wildfire
01-27-2019, 11:37 AM
Damn that water azeotrope. Chemists loathe rectifying alcohol because of it lol. Oh I forgot to mention that molecular sieves (at least the cheap ones I got) are not as effective as the magnesium sulfate. Epson salts in its anhydrous form has much much better water absorption potential than 3A molecular sieves. I can't speak for the high end sieves though. And you can boil the Epson salts together with the alcohol in the flask without releasing water. Sieves cannot be used while distillation is going on as they will release the water they initially absorbed and all your work will be for naught (even if you use high end sieves!). So when you use sieves you have product loss because you have to transfer it through a funnel and filter. In this process some alcohol gets evaporated and water from the air gets attached to the alcohol almost instantly. In the end it is just not worth doing sieves, but this is just my humble opinion.

Wildfire
01-27-2019, 11:56 AM
Hmmm. I don't know what to say about this one. I have some activated bamboo coal that I used in my initial rectifications and I can't say I saw a very positive result. But there different kinds of activated charcoal and you can have different sizes too. Whatever the case you have product loss as well as there is filtering involved. So for this reason I decided to go the distillation way only. Anybody has had any significant results using activated coal? Please let me know. Thanks.
May your labs remain redundant.

catmandu
02-04-2019, 04:22 PM
I am not sure what additives you have in the alcohol so not sure what you can remove by distillation. In my experience with wine, if you have the time then repeated distillations should make the alcohol taste sweet/candy cane like. I didn't think it tasted good untill 7 distillations/rectifications and it was sweet at 12 distillations. Sweetness can be a sign that the alcohol is purified at least if you are using wine. I also make sugar washes and the fermentation stage takes about 5-8 days if the temperature is correct.

Wildfire
02-16-2019, 04:46 PM
Yeah you're right. I had to do multiple distillations and the first few using Mg2SO4 as a drying agent to remove the water azeotrope. The alcohol was tasting sweet afterwards. Mine was store bought ethanol for fireplace lighting.