Acetone crystallization of THC-A


I think you guys are missing the best recrystalization solvent, Terpenes! Get yourself some plant derived terpenes and use that for the final recrystallization, if there’s any residual stuck in the lattice, it will just be terpenes! :slight_smile:




So you basically just get the acetone crystals then drop them into a small amount of say limonine then would you jar it then let it sit or would you leave the lid off the mason jar?


that’s the gist of it…

you probably want to get your D-Limonene good and warm first…because you want to completely dissolve those first round crystals.


No, u definitely want to crush your diamonds and then pull vac on that. Get all the acetone out that u can, then redissolve that into terps. Or else your going to still have a small amount of acetone trapped inside.



no point in recrystallizing from a mixture of acetone & D-limonene.


So why wouldn’t diamonds dissolve back into the terpene layer already present in the jar that’s the part that’s confusing me.


it would dissolve back into terpenes. then after the terpenes start to evaporate and you hit saturation point, the crystals will nucleate onto scratches in the glass or particles in the solution. If you are seeing crystals in your concentrate with no temperature or pressure fluctuation, then your concentrate is at full saturation and are in abundance of thca compared to terpenes, which needed to dissolve the thca. I dont know the exact number but i would guess when you reach saturation point you are probably near 9:1 thca:terpenes, so 90% cannabinoids and 10% terpenes.


What type of purity are we talking here? It this going to rival using pentane to crystallize? Clear or muddy looking lattice?


Is it safe to say that acetone extraction, when done properly, will preserve terpene profiles like that of its LPG (isobutane/n-butane/propane) counterparts?


That would make sense. It’s not polar and doesn’t have a similar boiling point to the terpenes. Also it should be easier to purge.



As to acetone’s polarity, here’s a list of common solvents arranged as to polarity,

Notice ethyl acetate is more non-polar, and 100% pure is available off the shelf in every state but California.

Kleen Strip labels theirs M.E.K. Substitute,

A mixture of ethyl acetate and butyl acetate is used in nail polish, the wickedly sweet odor is the butyl, the ethyl is much more mellow. Excellent dissolving power with relatively low toxicity.


I just got done looking …

U can actually get acs reagent grade food grade acetone…


We sell 99.7% acetone used in the semiconductor industry.


@Aurion @Future @ColumbiaLabsPDX @cyclopath

Well, what about using Pentane to recrystalize THCa, and preserve terpenes? It’s non-polar and its boiling point is 36° colder than acetone and a hell of a lot lower bp than etoh. It seems like it would be more likely to preserve the terpenes than the other common chemicals, ie hexane heptane ethanol acetone I hear thrown around; but not propane or butane, which we know that’s dangerous when doing post extraction filtration.

One other question I have is how soluble plant based waxes fats and lipids are in pentane vs etoh which is most commonly used with winterization. Why is etoh the conventional methodology for this and not pentane? It’s the same price, they are both class 3 solvents, but pentane boils much lower; am I missing something?

Additionally, Could you take terp sauce layer, add pentane, winterize, filter carbon scrub, and then winterize to increase the clarity and purity of the terp layer?


microcrystals on my photos on summer made of butane


I wonder if this tek would work well for removing THC out of fully decarbed hemp extract that is around 50% CBD? The goal wouldn’t be isolation of CBD, just to get the THC to < .03%. I’ve seen the pentane crystallization tek, but that looks more applicable to making isolate, and pentane is way more expensive than acetone.


I don’t have access to a rotovap at the moment. Will this tek work if I skip that step and let the acetone evap at room temp? I can blow a fan on it, or (worse comes to worse) I can hot plate/stir bar at a low temp to evap faster. I also have access to lab testing and can check my residuals/potency under R&D runs.


Howdy. Can anyone tune me in to the first extraction steps i.e. ratio of flower to acetone? What’s the best way to accomplish the wash; short wash in a mason jar or maybe flower packed into a stainless steel tube with the solvent gravity fed through? I was thinking perhaps 60 grams in a tube and wash through 600 ml of acetone, which is the amount of butane I used to used in the tube back in the old blasting days.

How much do you need to etch the mason jar and is that completely necessary?

Thanks for all the great info.