i see in this patent that CBDA can precipitate with water and alcohol.
extract at -75 Celius two washes 7 minuts each
filter with bentonite/carbon/DE cake
reduce in roto vap under vacum at 40 Celcius
LLE with alkane, evap in roto
dissolve in etoh
add 1/2 part of water and slow cold
cbda can precipitate.?
seems like a pretty obvious trick. its certainly well known that the solubility of cannabinoids decreases as the proof decreases. which increases the saturation level beyond the carrying capacity of the solvent…
look up anti-solvent & louche around here (or use the all knowing one).
The cbd-a itself is pretty hard to crystalize. You might want some seed crystals.
I haven’t tried myself; if you’ve fully winterized you’ll get the cbd-a out. Otherwise you’ll probably get some fats and waxes falling out first.
I’d be a bit worried you’d get an oil before a crystal, then in turn, you’d have some water and Ethanol stuck in your stuff. But in the right conditions, and with a bit of experience I’d certainly think it’s doable.
I think there’s 3 different isomorphs of the cbd-a crystal from what a little birdie with a master’s degree and some experience in crystal morphology
the questios is in the first message, with that procediment can i get cbda precipitate. and try to purificate the precipitation or descarboxylation … is for preserv the terps and not have to destilate… is an idea… dont know
Solvent extraction methods can produce an extract which includes an impurity exhibiting a detectable peak at 4.07 ppm, relative to a tetramethylsilane internal standard, as measured by H NMR spectroscopy. This impurity can be isolated in the form of a white residue in methods according to the invention. In a specific embodiment, hydrocarbon (e.g., n-heptane) extracts of Cannabis sativa industrial hemp containing less than 0.3% of THC which are desolvated to form white crystallites of impure CBD and/or CBDA. The white crystals are then redissolved in ethanol, pressurized liquid carbon dioxide, for example at or near ambient temperature, or supercritical or near supercritical carbon dioxide, and a white impurity with a melting point of about 8 1 °C. precipitates to form a separate solid scum which can be removed from the ethanol-CBD solution by sedimentation and decantation, filtration, centrifugation, or other recognized methods of separating solids from liquid solutions. These impurities are believed to be one or more long chain wax esters.
If you precipitate out the CBDA all you will have is cannabinoids and any impurities that co-prepitate. You wont have any terpenes. You will how ever have an “isolate” sitting in the low 90s.
This technique is know as antisolvent crystallization.
You could further purify this by dissolving in etoh and running through a thin patty of AC and t5. This will get you into the high 90s. Recrystalization of this will get you into true isolate purity numbers.
I know it kind of works with THC, but it makes a nasty emulsion that can only be separated by cooling the mixture and adding bentonite. Then the cannabinoids clump together and the solution clears up.
I’ve not been able to make good use of this process though.