CBD Crystallization


I have been running into the same problem with an 80% hemp cbd. Has anyone tried cutting cbd isolate into a cartridge?


yea i have. i make co2 pens and i bought some cbd isolate online and made a few different types of carts. some with mct some with peg for 0 thc and some with my subcritical co2 terp sauce stuff.


how about those industrial scale continuous countercurrent columns tho lol those things are legit


That is beautiful! What is the %CBD in your extract when you continue to crystallization?


You ask for % cbd in extract? Do you want to know the values for crude or distillate? I dont know what you mean by the continue to crystallization statement.


Apologies for the confusing wording. What I meant was what purity level (% cbd values) do you typically seek/get before trying to crystallize your distillate?


70-90% seems to work best obviously, however i can make it work with as little as 20-30%


Thank you for the reply. So you’re able to crystallize your crude without distillation?? Are you getting decent yields? I knew CBD crystallized fairly easily but 20-30% purity to crystallize is impressive. I’ve been playing around with crude trying to clean it up enough to crystallize without chromatography or distillation but havn’t had too much success. Are you using pentane? Any tips or small insights into your procedure would be greatly appreciated!


You can do it with liquid/liquid as long as you have dewaxed, once youve isolated the cbd cook off nonpolar solvent


Can you elaborate on what you mean by liquid/liquid? You have a solvent that isolated cbd from crude?


Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent.

Non polar solvent*


Yes and what solvent is used to extract out cbd and not other cannabinoids?





Can you explain more? Genetics of the plant?


Full disclosure: I’m a geneticist not a chemist :slight_smile:

IMO the best way to separate your CBD from other cannabinoids is the genetics of your starting material.

I can’t count the number of times I’ve been asked by patients how to isolate the CDB from their high THC cannabis. Yeah, it can probably be done, but you’re WAY better off starting with measurable amounts of your target.

If you want CBD, then plant something that makes 15% or more CBD in mature flowers. If it makes less than 0.3% THC, many states will call it hemp and make your life easier.

Crystallizing CBD from a 20:1 mixture is going to go much more smoothly that using a 1:1 feedstock.

@Plant2pipe suggests CO2 expanded Ethanol (or Acetone) as a solvent system. Theory suggests that should allow selective crystallization of individual cannabinoids. There are a couple of CO2 extractor manufacturers who are exploring the technology, but as far as I know its not something you can order delivered yet.

Growing the right stuff in the first place seems way easier this summer.


surprise surprise the geneticists thinks the best way is thru genetics lol
im jk i definitely agree


CBD synthase and THC synthase are different alleles of the same gene. Like brown eyes vs blue eyes.

Except in the case of these two, both enzymes seem to produce small quantities of the off target cannabinoid. Based on data presented in the paper below, one might conclude that CBD synthase makes more “off target” product than the THC version of the enzyme. Based on ratios I’ve seen by scanning testing company data, I’d say there are multiple versions of the CBD synthase, with off target production varying 10 fold (see below for alternate explanation. ie 1 CBD allele, multiple segregating modifiers).

THC synthase has been crystallized, so it’s 3-d structure is known. Although I haven’t tried, it should be possible to predict the 3D structure of CBD synthase by threading the primary sequence into the solved THC structure. (I used to play that game http://astral.berkeley.edu/)

A clever monkey might thus see potential mods to what nature (artificial selection actually) gave us to play with. Tweaking the primary amino-acid sequence to avoid the off target production of THC could be done in something simple (like yeast) and then moved (back) into our favourite plant.

It’s also possible that neither enzyme is actually leaky, and that the THC seen in high CBD lines is actually isomerization after the fact. (additional data from @shinyemulsion below)

I don’t currently buy that. IMO the ancestral form made both…and high boys selected for the happy juice… and have been selecting for it ever since.

Targeted work in the other direction has only begun recently, but the tools we have make it pretty straight forward. Even a small scale EMS mutagenesis on pollen would likely yield improvements in CBD:THC ratio.

So yeah, the geneticist thinks using genetics as the first pass it the right way to go. Save the CO2 for later.


Genetics is more of a necessity for creating isolate than a solution. Good starting material with low THC will help but regardless you’re still going to have to clean the extract of all the other “junk” extracted. So really genetics only helps to eliminate a purification step. Industrial scale cbd producers only use hemp already so I’m not sure genetics adds anything more at this point.


I absolutely agree that the right genetics are necessary, but not sufficient.

“Hemp” is a legal construct not a biological one, and not a consistently defined one at that.

If one is in a state where “Hemp” is defined as “used for fiber”, telling the investors that they ought grow Hemp won’t win you any prizes.

Do you have a solvent that will select one cannabinoid over the other?

With the right genetics you still have to remove the non-cannabinoid constituents, but that wasn’t the question I was answering.

As with most purifications, its better to not have the impurity in your starting material, and the higher amounts of target in your starting material, the easier your purification will be.



you should google the patents of one full spectrum labs re: enzyme conversion. They show THCA synthase creating CBD-A, THC-A, and even CBC-A, and they claim to control the ratio by varying solution pH. If correct, it really makes you think what’s happening in the plant, right? And can ratios be affected by growing conditions.

The interesting finding is that under NO conditions could they get 100% conversion to THC, CBD or CBC…

These enzymes are loose, period. So when you hear about 60:1 CBD:THC ratios in raw hemp, question the source and have it retested.