We didn’t have any batches finish for decarb last week, but we’ll have more than enough to play with next week. We already perform a very similar decarb process, and we’d only be making minor changes to our current protocol. We recently had cured, decarbed product for vapes come back at just over 20% terpene content, so I know the process works. Now it is just about optimizing it.
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Little to no change in the before and after ratios of terpenes?
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Not from what my nose and eyes can tell. Smells just like the flower, only stronger (at least on this specific 20%er I’m referring to). Not sure I have analytics to back that up, as stuff earmarked for carts doesn’t get tested until it’s ready to go into carts.
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If ultimate pressure calc says you’re exceeding the value of your PRV, said prv may let some of your precious terpenes escape.
Still a requirement!!
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Has anyone noticed if wet ethanol speeds up the kinetics of decarboxylation? From my experience things tend to decarb faster with a certain amount of water. My hunch is that it stabilizes the keto-enol intermediate which should lower the activation energy of the reaction.
Any thoughts?
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They have…
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Problem is separating the EtOH without accidentally pulling out terpenes, as per the thread “preserving terpenes”
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If you’re using isolate, this problem doesn’t exist. Has anyone done any experiments going down that rabbit hole?
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Not I.
Although I did put in a request for cannabinoids to throw down that rabbit hole only this morning… I believe the consensus was I first had to manufacture them, using other than our current production tooling, in order to earn my keep.
Which probably isn’t unreasonable given the current market.
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Seems legit to me. But only skimmed the first post this time.
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I wanted to thank the OP @Anonymouse for the decarb tek and detailed write up! We have been using this type decarb terp reflux process for 6+ months and love the product it produces. We also spin off hte, decarb diamonds, and reintroduce for a different product line, which is also really good. Both processes have their place but I love the taste of this terp reflux decarb method. I also agree with the theory that thca produced co2 during vaping is not ideal and should be minimized.
A couple things to note from my experience with this “theoretical” method.
- Assuming 125 PSI prv and typical 6" triclamp stuff, ~1600g of 85% cannabinoid, 10% terps product is the maximum in a 24" x 6" spool with 6" x 4" jacketed pot at 105 psig final pressure. 1200g seems ideal, and 600g is to little to get enough pressure rise for my 24" x6" spool. For 600g use a 12" length spool to double the pressure rise.
- That 1600g decarb at 110c took 14-15 hours with no agitation or stirring. Even 600g took 10-12 hours to stop seeing pressure rise. We are achieving 100% decarb, no thca.
- Pressure test/purge with N2 to ensure everything seals for at least an hour (with product in pressure vessel), as any leak or O2 equals funky terps that will need distillation to recover cannabinoids. Then vacuum down the vessel to at least -14 psig before starting decarb.
- Disolved co2, carbonation, must be addressed. As the write up indicates, heat up the final product and pull vac. I heat it to 40-45c in the jacketed pot and pull a vac to -14 psig for an hour or two. Then the material is warm enough and degassed enough to transfer to flasks for final degassing in rotary evaporators (thin film degas as mentioned in write up). Final degas occurs in small rotary evaporators at 40-45c with vacuum ramp up to -14 psig then hold until no bubbles are visible (1-6 hours).
Huge thanks to @Anonymouse and the f4200 community for sharing tech.
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I’m a little lost here because I thought the point of separating HTE and THCA is that we can decarb the THCA separately and add it back to the HTE.
If everything is decarbed together, this pressure vessel method might preserve some terps during the decarb process, but I’m guessing there still will be a lot of CO2 in the decarbed BHO. Wouldn’t using vacuum to purge CO2 damage the terpene profile?
How would you preserve the terpenes during the final purging process?
I’m guessing the thicker it gets with higher THC it will be harder for the CO2 to be purged. Therefore, more terpene loss happens.
I would think this decarbing setup can be very useful when I decarb the HTE fraction instead of the whole crude. I would like a setup like that if I have to decarb my HTE as well.
With that being said, is it absolutely necessary to decarb 100% for carts?
I was thinking maybe I don’t have to decarb my HTE if I add back the decarbed THCA fraction. If I make the HTE really low in THCA% like <40%, maybe it would be low enough of CO2 to cause no problems in the carts? Idk. any tips on purging CO2 out of the HTE?
@GreenSmoke I’m new to all this but working with numerous experts we ran across two schools of thought regarding decarb of full spectrum bho. Spin off hte, decarb thca (under vac), recombine which is the most popular method. Then you have the camp that prefers to decarb thca with terps present in a pressure vessel.
The decarb in a pressure vessel method carbonates the oil significantly. The degas process uses vacuum and temp to remove the co2, and yes some terps. A friend recommended rotary evaporators over vac oven, but either works and they both have pro/cons. I like rotary evap better but both need vac control or a human to avoid pulling a crazy vac and for sure volatizing terps. I automated a vacuum controller that ramps vacuum as programmed to avoid overflowing angry (highly carbonated) oil at the beginning.
100% decarb is not necessary, and I messed up a couple days ago and left 20% thca in a product by not heating it long enough. It still is in an acceptable range of 0-30% thca. Depending on terps that amount of thca probably won’t crash out in the cart. To increase my decarb repeatability without excessively heating the product I automated the process with a pressure sensor and a contactor to shutoff the heater. Now once the pressure rise slows and stops or almost stops the control system shuts off the heater.
A benefit/detriment of close to full decarb is the employee running the cart filling can run at higher temps to go faster and blow off more terps… all without getting co2 bubbles from filling/decarb.
Purge hte of co2 with vac oven or rotary evap.
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Beautiful!
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Here are the parts to make your own:
You need to put a PRV (125 psi), gauge, valve, and sight glass on that lid. I have already performed the jacketed vessel to spool size (volume) experiment. The 6x6" jacketed base corresponds to a 36" spool with 125 psi prv. With the sugar consistency BHO we produce, 2500g is the max that fits in the jacketed base. That results in a max normal pressure of 115 psi. Put that 6x6" jacketed base on a 24" or 12" spool and you will test the 125 psi prv.
Once full and sealed up, perform a N2 pressure test for an hour. Vent slowly, pull a vac to 28 in hg, start heater. Once the pressure stops building (4-24 hours) shutoff heater and let cool. Vent pressure slowly, remove jacketed base, move highly carbonated oil to flasks, purge co2 on rotary evaporator(s).
I hate watching gauges and hate paying people to watch gauges. Therefore I put a pressure sensor on the lid and tied it into a controller, wrote some gauge watching logic, and have it shutoff heater power when the pressure stops rising. @cyclopath let me know if you want to install this feature on your setup.
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If I understand Perrotin-Brunel, Verpote et al. kinetic studies and modeling correctly (your reference above: https://www.researchgate.net/publication/251476768) you can only get the Activation energy values they obtained by acid catalyzed processes . In other words for THCA decarboxylation under the conditions similar to those put forth here in this discussion, the only process is water or other acid catalysis. ( Here we are dealing with solutions of THCA dissolved in high boiling point terpenes.)
In an attempt to suggest a source of endogenous acids, they estimate the pH of cannabis flower material by measuring distilled water extracts of cannabis. (5.5 -6.1), I have done similar studies with trichomes and get pH 4-5. Considering such values they make no mention of modeling the ionic forms of THCA, only the acid (H). (???). Others have suggested:
“In protic solvents, kinetic data do not permit a clear distinction between (a) a unimolecular decomposition of the free acid or its anion, or (b) a bimolecular reac- tion between the acid or anion and a proton. This system is further complicated by the equilibrium be- tween salicylic acid and the ionized form. The con- centrations of the proposed rate-determining species cannot be varied independently.”. See: https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/files/1982-IV.-Decarboxylation-of-Salicylic-AcidsOxidation-of-Aromatic-Acids.807f.pdf”
Decarbarboxylation noted in this series of posts starts off in a combined solution of aprotic-polar terpene-solvent and liquid THCA, the latter being-protic polar (rescorcinolic acid).
So here not unlike “Butane works but no theory”, we have BHO extract, with BUTANE REMOVED leaving us with cannabinoic acids in Terpene solution at fairly concentrated solution. We have no idea concerning the “form” of the cannabinoics, homologous dimers, , monomers or ion pairs in the terpene solution. Moreover, the Energy of activation for the decarboxylation process seems to suggest either short chained, endogenous carboxylic acids or water complexes to act as catalysts.
These subtle differences in reaction rates and possible pathways (“theory of terp soup decarboxylation under pressure”) vs Perrotin-Brunel et al. “Solid state with water” should be considered somewhat different from decarbing 99% diamond form (undefined) melts.
Certainly this post contains effective standard and operational procedures, but its title claiming “theory” is a bit amiss. Excepting of course the math dealing with pressures which evolve if the reaction were to proceed with pure-melt THCA. Someone might “boil the terps” separately and get an idea what fraction of the total pressure they contribute.
Above reference: Perrotin-Brunel use salicylic acid models to help explain results. If you are wondering where the water might come from in a non polar solvent…read here:
Redirecting (Copy and paste). Pay attention to the hydrogen bonded water complexes and solvation rates in “non polar” supercritical CO2 for nice explanation. One might say this explains “why butane works so quickly at -40” and why the energy of activation values are so low in decarb studies.
Cannabinoic acid water complexes.
@cyclopath; @Akoyeh; @UneekkUserName
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@moronnabis In a cave man manner, I believe to understand what you and @cyclopath are discussing. Water and endogenous acids lowering the decarb energy. Interesting yall bring that up, I added automation to our decarb reactors to shutoff heat once PSI rate of change dropped off. It has been working great and gives really consistent thc/thca test results. We go for under 3% thca, ideally 0% but without excess energy past 0% thca. The automated system tracks times and pressures. The pressures are consistent but the time varies greatly, like 6-18 hours. Same product volume, same heater temp, similar thca/terp ratios…
I need to get a flow meter and temp sensors installed. That will give me energy into the jacketed vessel over time. Anyway thanks for giving me more to think about.
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If you were using what people refer to a “diamond form crystal” of THCA….crushed as input material for decarb do you have an average recovery number? We might have to account for the remaining THCA as well.
Or is this just a terp soup decarb we are talking about….ie decarbing in the terps under pressure? (The latter I assume)
I am looking for someone with some amount of what is referred to as Diamonds and crush it mortar and pestle style into a powder. Then put this powder into a microwave using 50% power and zap it repeatedly for 1 minute at a time.
A little square boat of glassine weighing paper with a gram of powdered THCA will do. Prezap the paper to remove any adsorbed water. Now after 4 or 5 repeated zappings with a 1 minute rest in between to prevent any heating in the oven components itself…do you find your self with an off color crunchy material that can be milled back into a powder?
We are not trying to decarb here…this is just gentle microwave drying and attempting to see if a diamond is a mono or dIhydrate…you would never know unless someone does a gravimetric study. If you have a CEM lab wave 9000 which does the whole process ….you can just pop a diamond in and go.
We can produce using water extraction procedures RCOOH forms of cannabinoic acids forced into this form by low pH precipitation (pH 1-2) and Re Extract into pentane ….upon evaporation of the pentane we get hydrates.
So the question is does a butane extraction of wet or dry biomass extract hydrates of R-COOH from biomass? (For the moment I am ignoring and conjugate base forms or complexes)
Studies with salicylate and supercritical CO2 (which has polarity similar to butane) suggest the answer is yes it is possible and highly favorable.
Because there is no control over the pH or water in a butane extraction and evaporation to terp soup…and diamond precipitation…what is a diamond?
Zapping a diamond with microwaves might help figure this out. Do it slowly at half power. IF there is sufficient water present it will super heat and decarb (thc goop)…so this is slow drying…it may or may not melt…but still recrystallized to amorphic state and remains crushable to a powder.
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IR can determine hydration number.
https://nvlpubs.nist.gov/nistpubs/jres/68A/jresv68An6p625_A1b.pdf
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