It looks exactly like the THCA isolate I made with that tech i shared using crc and cold propane to do a terp strip then butane to strip the cannabinoids. I’m pretty sure you have almost pure thca, sometimes i redissolve nasty bho in my material column to rerun, on top of my filter screen there always ends up being a white powder that tested 90-97% THCA the few times i tried and tested the results.
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This was the bottom of my 6" material column, I had a little less then a lb of BHO in there that I was dissolving to rerun through CRC, This stuff tested at 95% THCA after it was all collected, it would of been higher but you can see a decent amount of yellow in clumps.
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Lol not as refined but alot less hassle 4 sure. Did this a few yrs back in neg 8 degree temps. I’ve only messed around def dont have your guys equipment and I only do personal so mostly rosin.
Yeah its surprising how far a few percent go in terms of melting points. Honestly, if there is a well corroborated melting point for a compound I’ve always liked using melting point for indicating my purity. The thing that can sometimes skew this is if there are different polymorphs of the same compound. So 99% purity of polymorph A has a different melting point than the same purity compound as polymorph B just because the intermolecular forces (which must be overcome with heat to melt the compound) differ because of their geometry.
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Im under the impression that THCa had only 1 polymorph to it’s possible lattice structure. Anyone want to provide contrary evidence?
Do all of the THCa isomers share the same polymorphism?
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Undoubtedly different since it isn’t just a stereochemical shift but a complete relocation of a functional group, thereby altering its electrostatic interactions drastically.
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You can perform a crystal-flip (change your polymorph) by recrystallizing out of different solvent systems - this is a known technique. In other words, take some pentane crystals and dissolve them entirely in ethanol and recrystallize will result in a different polymorph. My prediction based on my own observations is that crystals from light hydrocarbons (nC3-nC7) differ in polymorph from those yielded in ethanol, for instance. Generally, different solvents will not yield the same polymorph whether because the solubility changes or because of intermolecular forces between solvent/solute etc. I can damn well guarantee you there are multiple THCA-A polymorphs because…well for one I’ve made them and more to the point I have a background in scaling/performing scaled crystallizations.
@Future As for THCA-A vs THCA-B structural isomers, my prediction is they likely have different polymorphs/crystal stuctures on some level and probably difference melting points. The location of the carboxylic acid relative to the phenol influences hydrogen bonding for instance, or overall polarity of the molecule, or bond strain/angles, or electron distribution across the molecule - lest we forget they are in fact different molecules. It would be a real coincidence in my opinion if that change had zero influence on how the molecules stack upon on another in a crystal lattice. I haven’t proven or done with my own hands (I’ve never gotten ahold of considerable quantities of THCA-B and would likely need to synthesize this which I don’t have time/value for currently) - rather, this is a situation where I’m making what I consider a reasonable prediction based on my understanding and experience with crystallization.
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Good shit… I’m gonna try growing some 150 proof ethanol crystals and see how it goes. Gonna leave it open to the atmosphere so the ratio of ethanol to water decreases over time resulting in percipitation. Gonna try this with a really dirty batch of crystals and see what happens
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Woah that went deeper than I expected
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Some runs when stacked too tight, or real gummy material couldn’t dissolve fully and left chunks of yellow in the white powder for sure. Best I had were shatter pieces broken up real small and lightly packed in there, they came back pure powder. So you did get it tested as thc-a?? Still so curious how only 25% of the original material remained!
Similar to the acetone tek?
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Essentially, but with the addition of an anti solvent. I’m most interested in trying this in a solvent that has hydrogen bonding, as all my previous acetone crystals look essentially the same as my butane crystals
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Looks like isolated “A” to me. Maybe the amount of solvent you used was more than enough to separate some of the A from your oil and the sock worked as a filter to retain the isolate. Kinda when you add tane to terps to crash out the A in a jar. I don’t know how cold your solvent was but if it was cold enough it could happen.
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Did not chill those injection, just ran room temp
I was convinced I read that here to by one of the wizards but f$&)( it s hard to find certain post from the past if you need to
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If that stuff is insoluble in non-polar solvent for real (not just guessing butane, but trying pentane, hexane, heptane) and it is not sticky, then it is very likely mineral from a busted CRC filter leak. It may be coated in organics so that it dissolves in alcohol, but not water or straight non-polar.
However, my guess is THCa. It should dissolve just fine in alkanes and lower alcohols under room conditions. It is the pressure differential in the extraction system, along with cold temperatures, which causes this to happen. This is exactly the type of material I used in my pseudo-polymorph experiments with 3 n-alkanes on Instagram.
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Yep! This is one of the secrets of the high pressure differential across a fine filter screen I was talking about with those conical Bizzybeest filters on Instagram! 
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Pretty positive it was not from busted crc filter, I use many many filters of varying styles stacked as backups and the last ones are always clean. Can’t remember if I wrote this out already or not but
my B80 is vac packed and compressed over
(2) 2.5um paper filters in a filter plate which get most of the powder,
then a 5um mesh gasket, which gets tiny bits every time that I brush off,
then 2more 2.5um papers-stay clean every run,
a layer of Pyrex glass wool sandwiched between
2more 2.5um papers,
and finally a killa 5um sintered disc as a last resort for any failure.
That one I’ve never had even a speck of dust get to. By now I feel it’s super overkill and want to remove some of them for better flow but I really didn’t want any B80 getting through. With N2 I can get really nice flow rates anyway and beautifully clear solution even from dark yellow unfiltered solution so I’ve left the backups in there. I’ll put some pics up later.
So next time I am able to do some research runs I want to try two new tests.
- put white powder direct into collection and run fresh butane into it, see if I can get it to dissolve. In which case I could reintroduce it into other slabs to recover it
- re run low quality/ sugary oil withOUT a sock, see if the powder can go through my crc filters or still gets held up.
Oh the socks were AZ pressco 90um nylon
After reading all the info passed around on this thread I’m definitely leaning towards a THCa isolation. What I’m thinking is that when the oil was in the sock originally and the THC was in lower concentration all the terps and other oils, cannabinoids dissolved out faster with some of the THCa, then as the remaining THCa came to 95-99% purity it crystallized up into bigger pieces and could not get through the 90 µm filter socks.
Anyone want some pure THCa isolate? Got a few kgs sitting here
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