I have recently had extra time (a very rare occurrence), and it dawned upon me that I’d like to insert the entire playbook of remediation for my EtOH-extracted distillate.
The process is as follows: Cold EtOH extraction (generally between -40 and -20C), cold bag-filtration 10um->5um->0.5um, solvent recovery, decarb, terpene strip, distillation.
My intention is to take that first pass distillate and do the following:
Water Degum - Add 10% neutral RO water (not brine) to 1st Pass Distilalte, stir at maximum RPM and 90C for 30mins. Cool Solution to RT, filter (if needed).
Citric Acid Degum - Titrate Citric Acid Brine* into solution, until pH = 4, stir at maximum RPM and 30C for 30mins. Maintain Solution at 30C
Neutralization - To prepare for enzymatic degumming, the solution must be neutralized (so as not to denature phospholipases) – titrate Sodium Bicarbonate Brine** until pH = 7.
Enzymatic Degumming - Hydrate enzymes with minimum water required, add them to the (now) neutral solution, stir at max rpm and 37C for 30mins.
Recovering Cannabinoids - Add 2 parts n-heptane to solution, shake (or stir) vigorously, and allow to settle. Drain water and emulsion to waste. At this point, the water soluble component of the gums should have been removed from the solution.
Winterization - Recover n-heptane and redissolve cannabinoid fraction in 190proof EtOH. Cool to -40C and allow to settle for 24 hours. Filter over Celite in aliquots.
Brine Wash - Recover EtOH and resuspend cannabinoids in 2 parts n-heptane. Wash with 20 volumes of acidic brine, 20 volumes of alkali brine and 20 volumes of neutral brine.
Hot Scrub - Add 5% T41 to heptane-cannabinoid fraction, safely heat solution to 50C and keep well mixed for 30 minutes.
Chromatography - Prepare a column as follows: 0.5 parts Celite on top of Grade 1 filter paper, 1:1 Magsil PR on top. Pass primary fraction over column and rinse through with 3 additional volumes of heptane.
Color Scrub - Additionally, different media can be used to further remdiate the color of the solution (T5, silica, W1, W2, W3, AA, etc)???
2nd Pass Distillation - This one is obvious.
Given the extremely convoluted, complicated process, yield loss is an absolute certainty–do not expect that this will retain all cannabinoids.
*Citric Acid Brine = 7.5% NaCl in RO Water, pH = 3 by means of Citric Acid
**Sodium Bicarbonate Brine = 7.5% NaCl in RO Water, pH = 10 by means of Sodium Bicarbonate
***Neutral Brine = 5% NaCl in RO Water, pH = 7 by means of acid/base
I’ve recently tried dewaxing via LLE. Add 1-2 parts non polar to 20 parts alcohol cannabinoid solution. Mix, settle and discard non polar layer. Should remove some nasty stuff
Ahh, the methanol is crucial–evidently cannabinoids prefer methanol even relative to non-polar alkanes.
Makes more sense this way–methanol holds cannabinoids, non-polar layer siphons off waxes. Plus you get the added benefit of the stuff precipitating out in the methanol at room temp, so you can see it being removed from the methanol layer.
What kind of enzymes are you using? What is the optimal reaction pH of your enzymes?
The reason I’m asking this is because I’m familiar with enzymatic degumming in vegetable oil. The industry standard is the use of lecitase ultra pla . This particular enzyme has an optimal reaction pH of ~ 4.5. It reacts with all phospholipids (PC, PI, PE and PA). And as you may know, enzymatic degumming reduces the loss of oil. In fact, it’s more efficient than caustic degumming in that respect so I don’t understand why you’re using the other techniques. What’s your percent recovery after the process is completed?
I’m not certain of recovery following this barrage of methods. I wanted to put it out there first and get some opinions
Also, I’m glad you mentioned pH of the solution affecting efficacy/cleavage rate of the enzymes themselves. I’m using Yang et al from 2018 as a starting point, they say pH of 4.9 is optimal so I was thinking about going to around 5.
I feel that the problem will not be the initial PL cleavage (achieved with citric acid), but the hydration of the PAs created and retained in the non-polar layer. Some folks have mentioned saponification, but I fear that I may over-acidify the solution will pull cannabinoids into the aqueous phase (around pH = 12) by the time those non-desirables fall into the aqueous phase.
The reason I’m acidifying-> “neutralizing” to pH 5-6-> incubating with enzyme, is because this the typically process flow that is seen in industry—just copying the folks that have it figured out already.
Oh I see. Im totally on board, no need to reinvent the wheel. I was just curious to why you were taking the extra steps, but thanks for clarifying =]
pH is very important for enzyme activity to occur. So in order to yield optimal results in a reasonable time you must streamline the process by making sure that the parameters that governed the reaction are fixed. Fluctuations in temperature will negatively impact your pH. Additionally, doing it under vacuum is recommended. It’s supposed to speed up the rate of the reaction, but it’s not necessary.
I used to use only 10% methanol in water and it worked well with minimal losses to the nonpolar/cannabinoid phase (though I don’t have the exact data anymore).
@TheGratefulPhil titration/pH adjustment may be in order after Step 9 (MagSil chromatography). Or after the final brine washes, if no chromatography is necessary. Neutralization of the water isn’t enough in my experience (pH vs pKa explanation from someone more knowledgeable, perhaps?)
I find that chemical degumming (saponification, acidic degumming, etc) removes major redness more than enzymatic degumming, while enzymatic does a little more for strictly clarity. A more chemically-driven explanation would be great but that’s the best I can put it. I think it’s as simple as the water solubility of the broken down phospholipids, which is irrelevant during ethanol winterization.
Though I agree with @Kingofthekush420 - I’ve really never found both necessary for the same batch (though I’ve done it just to give that oil what we call “the gauntlet.” Great headstash material!)
So after final chromatography through MagSil, how would one pH up? I’d imagine this stuff lowers the pH because it has an affinity for acidic compounds (i.e. why it pulls compounds with lower log Po-w)
All I have is hydrion paper.
Also, how many volumes (in your experience) of alkane should be flushed over the chromatography column following the first distillate/heptane mixture?
Silica60 is acidic. Magnesium silicate is alkaline. The best neutralizations for me were done by titrating aqueous solution into 190 proof ethanol solution, then removing ethanol and reintroducing heptane and distilled water. Labor intensive, I know. But I’ve had a few instances of inability to avoid purple oxidation no matter how many distilled water washes I gave. As soon as I adjusted with the above method, I got gold.