With plain silica the ability of column chromatography to separate low CBD from high THC is much better than separating low THC from high CBD. Both are tough
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Have you tried using pressure and temp as described?
Nope that is new to me. Iāve never had proper equipment to work under pressure. Itās a glaring hole in my knowledge
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This could be conveniently achieved with acids directly extracted from biomass, just through an elegant set of reactors, without even the need for chromatography.
Be here with dealing with oils. These oils might still present variable P/T dependence of their solubility in supercritical CO2. But such approach would turn out to be more messy than with salts.
The next evolution could be a density separation, perhaps it is possible in superciritical conditions.
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Still, SFC chromatography in itself may also work.
But it needs research. It seems other medium than silica are necessary.
There are few reports of such test in another thread on d8.
This sound not complexe, but is not a poor man method at all.
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These pressures are fairly low for SFC, this should be easy enough to pilot. Iām a little surprised an entrainer isnt necessary though. CO2 is still very nonpolar at those parameters
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Well Iāve got a columnā¦ And some silicaā¦ And a supercritical pumpā¦
Sounds like a doable build at some point here. Iād need to figure out the multiple receiver setup. I guess it might be as easy as making a manifold from some swagelok
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Gonna probably want some sort of accumulator too to reduce pulsing
Yeah, proper heat control might be a bit of an engineering problem as well. Although a shotgun style might do just fine as long as we have a slow flow
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Shouldnāt be too bad I think. Make a tube and tube going into the inlet and just run a kiddie pool pump to cool in incoming to just over supercritical, then jacket the column at the setpoint temp. Run a BPR on the other end of the column, and just make sure itās all pumped up to pressure before injecting the sample. I can sketch a diagram up, itās probably only $300 worth of parts other than the pump, column, and BPR and theyāre all parts you already have Iām sure
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Yes the above mentioned pressures-temperatures mentioned are subcritical. But these are precipitation parameters for acid cannabinoids, at the end of the process. For the chromatography, one would need them to move and thus be eventually solubilised, thus critical conditions are required at some points. The solubilities of non acid also differ from one to another in critical conditions, but not to the point where they can be fully separated just based on varrying solubilityā¦
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patent images and diagrams to right of patent language
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Edit: well fuck @tweedledew I guess my fat thumbs just made this open source for those who have enough time in here lol
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Also, to continue the discussion, hereās my relevant question from the edit:
Iām re-reading what @anon1342 said and Iām thinking maybe weāre getting ahead of ourselves: Iāve always wanted to turn out high pressure SFE into SFC equipment but it seems like what heās talking about is basically crashing the cannabinoids based on their solubility in CO2 at different parameters and Iām concerned about the āholdup volumeā. Initially, the CBD may precipitate before the d8 then the d9, but I imagine you wouldnāt be able to crash very much CBD before starting to encroach on the saturation of d8 and so forth.
Am I missing something?
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normally crashing at temp is not that easy.
often you get other substances comming out as well and its more of an equalibrium from my
experienceā¦
the temps and pressures are very close as well.
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Iām very interested in hearing if you have looked into this more or experimented
I have not looked into any kind of fractional precipitation like what was discussed above. Frankly, Iām so sceptical that it would work that I will probably never experiment with it lol.
I have been sketching up frits to go into the extraction columns of all these out-of-use CO2 extractors to turn them into giant HP flash systems.
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This is bizarre- we were literally talking about this exact thing yesterday
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The way I see it, thereās a couple hundred good 5000 psi+ capable columns and appropriate solvent pumps just hanging out unused all over the US. You could pretty much just hook up two variable speed dosing pumps to supply your mobile phase constituents to a feed tank on the inlet of the existing pump and bing bam boom, you have a gradient elution system. Once you do a little validation, you could almost get away with using an egg timer and diverter valve on the outlet for fraction collection lol
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Haha- be nice to have some UV detection too