Particles in roto boiling flask???

Why wouldn’t I want to use ethanol vs isopropyl

Looks like water solubles to me. Are you also getting precipiate on decarb? It will be more sludge like in that case.

Check out my bucket Tek for an extraction and filtration approach that should eliminate this issue.

?? $$

Where did I suggest iso?

For folks in OR, and Northern CA, I’m an advocate for the hippy friendly folks who used to be alchemicalsolutions.com (now organicalcohol.com) in Ashland.

Isn’t 190 isopropyl? Or I’m totally understanding that wrong and you mean 190 proof vs 200 proof. Now that I am more awake I realize what you wrote. Sshhhh. My coffee and cannabinoids hadn’t kicked in

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With that said, why wouldn’t I want 200 proof etho and extract -70 or colder?

Both those are covered here I believe

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I was planning on using ethanol, regardless. I was wondering what the difference is between 190 and 200 proof. And why wouldn’t I use 200. And if do extract at -70 do I need to reproof it or dehydrate, or if I’m using the incorrect term the correct one later on. Or, if I roto/recover at a low enough temp I will be good?

You can start with 200proof etoh. Many do. You’ll end up with 190 in short order. 190 is probably ideal.

Get a proofing gauge, and learn how to use it. Temp compensation is important.

Rotovap has been reported to be useable, but that was not my experience.

190 is azeotropic ethanol, typically at 95.63% ethanol and the remaining as water. 200 is 100% ethanol. Once you crack open that 200 proof though, it’ll start pulling in moisture from the air until it hits that azeotrope at 190. Molecular sieves can be used to “dry” your 190 proof, but it’s not foolproof.

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I haven’t decarbed it yet so i’m not particularly sure about that. I will try your filtration approach. I will also try re-proofing my alcohol. Although, bvv has a 55gal drum of 200 proof ethanol for $450 so I may just do that because I can’t seem to find a straight forward re-proofing technique.

I will be joining GLG monday so hopefully i’ll find something useful in there!

Thays denatured etoh, not food grade at that price

“Future Readers” idk if there was a pun there.

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I have written several treatises on the pros and cons of 200 proof ethanol, 190 proof ethanol, denatured ethanol, and isopropanol (which is not ethanol at all).

Every one of those except 190 proof ethanol fails to perform highly selective extraction. They all extract vegetable oil (fats) and epicuticular wax to varying degrees, just like hydrocarbons do… and they keep a lot of those undesirable materials in solution even at very cold temperatures, just like hydrocarbons, but to a lesser degree.

Using 190 proof ethanol at -70°C is perfectly ideal. You still want to use short residence times (brief contact with plant matter) to avoid extracting sugars, proteins, and other deeper cellular materials, but 190p at -70°C is the most selective solvent for cannabis, period.

…and if you absolutely cannot stomach the taxes on potable (drinkably pure) 190 proof ethanol, you can use the new 5% n-heptane-denatured ethanol by adding 4.15% distilled water to it by weight. That will make the 95% ethanol present in the denatured solution into just over 190 proof instead of 200 proof. The small remainder of the needed water for the azeotrope will be absorbed from the air and plant matter (even dry plant matter has a little water available).

Speaking of which, re-proofing any 190 proof ethanol is only necessary if you intentionally add excess water to your resin solution, and then you force that excess water to mix with the azeotrope in your rotovap or other recovery receiving vessel upon recovery. To avoid doing that, perform recovery at 40°C or so until the ethanol azeotrope stops condensing. When you see white cloudiness in the resin, that is the excess water (that was not part of the azeotrope) emulsified with the resin. Drain your receiver of the azeotrope you recovered, then raise the boiler temperature to evaporate that water out of your resin. The water collected after the resin turns dark again (no more white clouds) can be tossed.

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If I was going to be running counter current, kinda like a bizzy system or similar. Would that be a short enough residence time, along with efficiency of time and amount of solvent?

I appreciate the knowledge

See my edit above. I don’t know what you mean by countercurrent in an extraction process. Liquids or gases must be moving in opposite directions, such as in a condenser or other heat exchanger, for it to be called countercurrent.

Just curious what happens if i don’t add the distilled water to the 200 Proof Ethanol?
Is the 190 Proof required for the extraction process, or is a process issue?

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I’m using the reference wrong, my bad. I’m thinking of a different phrase that I can’t remember, I’m sorry. But as using a chilled solvent tank and chilled column, like a standard butane extraction setup, but using ethanol. And from the collection to roto or treatment. Then spd.

I was under the impression that it was an efficient use of etho

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If you open the bottle, you will end up with 190. Details on why 190 is better for this task are available from links provided in this thread.

Maybe check out one of the treaties @Photon_noir mentioned?

Ethanol Extraction White Paper

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Is there any way to really modify a bho extractor to use etoh

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@PofH As @cyclopath mentioned, 200 proof ethanol is hygroscopic (absorbs water from moisture in air) until it reaches the azeotrope of approximately 95% ethanol and 5% water. Yes, it is best to use 190 proof for extraction, Winterization, etc. Always cold and short contact times.

@dred_pirate No worries on misused terminology, I just wanted to clarify what you meant.

@GroovyOctopusLabs Sort of, but not really. Because one can use short contact times for almost any solvent extraction of cannabis, the whole “tube shaped extraction vessel” concept is rather outdated. If you look at industrial essential oil extraction facilities, you will find a lot of extractions being performed in a very short, wide vessel. This is because such a form factor minimizes the drainage time, thereby minimizing the difference in contact time between the top of the herb mass and the bottom. Also, as you are aware, ethanol takes more energy [e.g. than butane] to recover/distill out of the resin. That is why thin film technologies, such as rotovaps and FFEs are used in ethanol recovery. Granted, a very hot (and preferably stirred to avoid scorching) pot still also works for ethanol, but it is more complex and higher energy than a simple warm-water jacketed butane pot. Finally, chilling a column shaped extraction vessel and running cold ethanol through it is extremely lossy, since ethanol (and even butane) will only evaporate/drip dry from the biomass very slowly or not at all, even under vacuum, in super cold conditions.

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