It’s a common misconception because people refer to reclaiming their solvent as “distilling” from the oil. You get your solvent (etoh in your case) back, and you’re left with your crude oil.
The plan is absolutely to winterize, or at least, to do the extraction at dry ice temperatures and see what effect winterizing has. From what I’ve read, doing the extraction at those temperatures leaves it pretty clean from waxes and such.
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This makes sense, the distilled part is what you collect, so the rotavap definitely wouldn’t distill the crude, just the ethanol. rotovap is still distillation equipment, but not for what I’m trying to distill.
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So you’re going to chill the alcohol to -78c and then do the extraction? Followed by filtration?
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That’s the plan, yeah. Then the filtrate would ideally be good to go into the roto if I didn’t need to do anything else with it beforehand.
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Yep. That is not winterization, but may well get you to an almost cart ready crude.
If going that route you might Decarb under pressure to retain terps?
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It is a distillation apparatus, but as you’re now aware, not for distilling your cannabinoids, or making the product known in the cannabis trade as “distillate”.
If you need terps, because you cooked yours off on a hot plate, then you have to purchase them. Sources for those can be found here too.
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I guess winterization is specifically when you let an ethanol extract sit at temperature to let your impurities precipitate out? doing a filtration right after a cold extraction would be a shortcut to that process? if I’m off base here let me know. And I’m going to check out the link here. i can’t speak your guys’ praises enough. thank you all for your help.
If you extract cold you don’t pick up much in the way of waxes. If you concentrate that primary extraction, then get it even colder, you might drop some fats and waxes that you can filter out.
Right now you are simply filtering out the plant matter (particulates).
Check out the bucket tek thread & get yourself a panda with a sock in it.
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Here is my drawing of the entire process from Cannabis extraction to cannabinoid distillation. It includes solvent recovery using a falling film evaporator, which operates on the same basic principles as a rotary evaporator.
…and here is a simplified version with a more refined appearance, but far fewer details.
I hope these are “worth a thousand words” insofar as explaining how cold ethanol-based cannabis extraction generally proceeds.
One thing they may not reveal is the purpose of using low temperature (and 5% water) tuning of ethanol’s selectivity as an extraction solvent. The main reason for this is to avoid the necessity for excessive post-extraction clean-up of the liquor. Warm extraction with ethanol can bring a lot of undesirable compounds into the mix, such as sugar, protein, alkaloids, etc.
Another useful fact is that you do not need to worry about the efficacy of the ethanol for multiple extractions; as many as can be done before the alcohol is naturally lost to evaporation, in fact. If there is excessive water in your biomass during extraction, the ethanol may pick up some of it. However, when you recover the ethanol in the rotovap, only use temperatures below about 50°C. When you see the crude resin get milky splotches forming in it, empty the ethanol from the receiving flask and store it for other runs. Then, after resealing the system and pulling vacuum back down, turn up the temperature to 60-70°C to evaporate the milky watery splotches. When the crude goes solid black/brown again and you no longer see drops of condensation forming in the condenser, your crude is perfectly concentrated and ready for the decarboxylation & devolatilization phase of the process!
And fyi, no, you cannot effectively decarboxylate while solvent is still in the crude, because the solvent’s evaporation cools the resin, keeping its temperature at or near the solvent’s boiling point for the given pressure (which is easily below room temperature under vacuum). Once the solvent is finished evaporating, the resin stops “sweating” (i.e. evaporative cooling), so its temperature is free to increase to a degree more effective for decarboxylation (110-120°C).
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This might be my favorite comment in the forum, ever.
That first picture is perhaps the most useful thing people could find on here.
Thanks, dude.
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Aw, thanks! You’re welcome, of course! 
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I’m stunned at how much information is here. It’s like everybody is competing to be most helpful. Awesome, somehow you managed to nail what point in the process I’m at in terms of understanding the system at a glance and getting my feet off the ground. Thanks so much.
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Fucking awesome man…as always
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If someone happens to know then:
If what I was planning on making wasn’t distillate, then what the hell is it actually? EHO? Seems like something smokable safely, just shittier than distillate. I think it would be best for me to look into a SPD rig, but in the meantime, what would I have been making?
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I literally saved this first picture to my work computer, it is everything and more that a newbie could ever dream of being useful. As always, very well done.
@tuclibys If you’re only extracting one strain at a time I would commonly refer to what you’re making as Strain Specific Extract. I don’t know what your end goal is here? It seemed like you wanted to throw this into a cart and then sell that? If this is the case then you really need to purge the hell out of your extract in order to get the solvent off. In doing this you’re probably going to destroy your terp profile and I assure you its not going to taste the same as the original terp profile in the plant. Making a cart out of pure SSE is honestly not going to work. The formulation is going to be too thin and will probably leak out of your cart. Also, if the ppm of Ethanol is 5000 ppm (0.5%) in Canada you are not going to want to try and fill carts with just your extract. Just FYI I’m in Florida and our regulations for medical dropped a few months ago and our state requires 5000 ppm of Ethanol for all vape products so this is pretty common as far as low levels go for that solvent. I have posted in here a few times in an effort to stir up ideas on how to remove ethanol and still retain terps but it really is seeming like an impossible mission. You can do some digging around here and probably find the posts I’m referring to. If you want further help or the search bar seems to not be working for you I can try and assist.
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EHO is the term. It’s going to be lower potency than distillate, but it will have more terpenes than distillate which can be a plus.
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Yeah, I’m beginning to accept this. It’s more important to get a decent quality thc yield, and if I’m looking to add terpenes I can still do that afterwards. I like the idea of doing an SSE but if it’s not what I can start doing, I can focus on it later.
Why is that? too thin? If I can’t do an SSE I’m okay with that; if the full terp profile dilutes it too much, I’m okay with using a proportional amount fewer terps as well, but primarily yeah I don’t want any carts to leak.
Thanks so much.
@tetramethylsilane Thank you, noted. I’m okay with EHO as well, as long as it’s quality overall.
@cyclopath When you’re running your EHO/distillate (whichever it is on a given day; I’m not so privy to your processes) in your pens, which I saw from your other thread that you get from R&D, what sort of typical thc% do you end up with (if you know), and how would you rate the flavor compared to distillate?
I’m going to let you know this because once you see some things on a GC you can’t unsee them. The terps you buy that claim to be pure are not at all pure. They have so many peaks that are other terpenes and even solvents sometimes. The major peak on there is the terpene in question but it is surrounded by so many other peaks as well. If you can get away with adding as little as possible I would recommend that. If you could get a wipe film you could just use the distilled terp fraction and the cold trap terps to make your carts hella fire. Add back 8 to 10% SSE and you got yourself a gnarly cart.