A (likely) unsolvable problem with ethanol extraction (keep them terps!)


I’ll look into the TSA, not sure what you mean by it.


Well, for large scale.
Energy costs would need to be factored but seems like the fastest and most cost effective way would be automated filtration post membrane through sieves.
No distillation needed. The exception being running etoh and water as a vapor through the sieve(s).

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Ohhhhh, running the whole system via sieves with the crude and everything in there already? The having full spectrum oil drop out? I was assuming you meant just the terp recovery.

I guess the ethanol recovery would be a similar amount of energy as distilling it anyhow.

Am I reading that right now?

You’d need to have some pretty massive chambers for the 4A zeolites with the amount of solvent you’d be dealing with. Then need to recover solvent under vacuum (more than likely).

The zeolites are exothermic in the absorption as well, I’d think the oil might slide out decently well.


First filter for heavies like wax and chlorophyll
Second filter separates oil / etoh&water

Solvent recover and crude are done

It’s possible to run crude through a membrane and fraction it idk? Molecular size may be too similar and need distillation.

Seems like the test results this week (77% cbd in crude for hemp 88%thc). Isolate for cbd may just need decarb and then crash it out.
Haven’t been onsite or seen the labs but that’s what I was told.

Returning to the solvent mess…take the terps and water out.


Are you talking about membranes or adsorbents right now for the etoh/crude separation?


Membrane for that separation (solvent / crude)


What could be done with remaining hydrosol?


its puts the cannabis in the hopper and loads it in again


I didn’t see what part you were refering to but I’m guessing after solvent and crude are separated.
The hope was to find a good solution there — possibly seperate terps out with a 4a sieve.
vaporize the etoh and water into some 3a to capture the water.
There should be something above with regards to fuel industry and how they handle ethanol purification but that’s the idea :man_shrugging:

What would work better?


Idk jd coalescing filtration or demister pads would be able to remove terps first

—the water and etoh would then go directly to 3a to adsorb the Water. Wouldn’t need 4a


I think some of the turpenes are alcohols, or very much like them. Not 100% on it though. I really should just do a proper lab test on this so we at least know what we’re isolating


I was curious since I have just been saving the hydrosol layer. Maybe I’ll make soda :yum:. I have heard LLE with Hexane and DCM works although DCM isn’t something I’d want to use in my lab. @tweedledew mentioned using a polar adsorbant to grab all the terpenes and then use SFE to extract but I’m not sure what the best way is in terms of time/results. SFE in my experience is slow and expensive but produces great results.


Agreed :100:


Hexane and dichloromethahe are miscible and neither is miscible with water

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You’re right my mistake.


I’ve got a feeling (not the best for science… I know) but it seems like all the tastiest stuff in life is done low & slow or more labour intensive. Obviously I don’t want this to be the case, but in anyone’s processes in any solvent, seems like time + labour spits out quality.


That’s why we work in labor-atories, so to speak.


Hahaha :joy:

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These guys Are selling DCM
Seems like it’s a pretty dope solvent lol


If you haven’t done small scale steam experiment on your material you should. It can affect yield and quality. There are several basic design types of these stills too. If your goal is just cranking out for your own use, I know a guy. We are selling one of his smaller stills. I can get deets but I think max is 100-150 pounds.

This company has a nice design:


Be aware that plenty of people are doing this, so quality will really make you stand out. Also, a few pesticides will carry through into the oils so do a little research on this. I can’t disclose which ones but it’s in the essential oil literature.