Limonene extraction of cannabis

[Daub Marley]

Its seems like it wouldn't be much of an issue to get rid of residual limonene. Just use a rotovape to remove most of the volume and then add some water at the end. Then short path and it should be completely gone. Honestly there's really no reason why it wouldn't come out in short path distillation. Most of the predominant terpenes in cannabis have the same molecular weight and can be removed by spd. Why would limonene be any different? The boiling point under vacuum is going to be way different than its referenced boiling point which is done under standard pressure. The referenced bp for THC is way low and believe to have been done under vacuum. If you were comparing limonene and THC bp at room temp there would be like a 250° difference. This makes sense because limonene is a liquid at room temp whereas THC is pretty solid. Just this qualitative observation (viscosity at room temp) is enough for me to safely assume there is a large difference in bp between the two.

 

[Ollie]

In a recent HC episode, there where talks about the actual boiling point of THC is 420 degree celcius.

Hash Church LXIX 69 (1:36:00 / 1:39:57)

 

[Pastelero]

The boiling point of d-limonene is much higher than D9-THC and D8-THC and very close to CBN.
RB

this was long time the status quo, but this is now outdated!

BP of d-limonene is 176 °C
BP of THC is 420 °C

 

[Gray Wolf]

this was long time the status quo, but this is now outdated!

BP of d-limonene is 176 °C
BP of THC is 420 °C

The 420C boiling point for THC, flies in the face of published data. My Merck Index shows it as 200C @ 0.02 atmospheres.

 

[Pastelero]

The 420C boiling point for THC, flies in the face of published data. My Merck Index shows it as 200C @ 0.02 atmospheres.

Rafael Mechoulam determined THC's boiling point to 155-157°C (311°F) at a vacuum of 0.05 mm of Hg, this was published in JACS (Journal of the American Chemical Society)

At atmospheric pressure, it appears the nomograph predicts about 420°C (788°F).

 

[SkyHighLer]

That can't be correct, you've all seen THC boil off rapidly at much lower temperatures than 420C/788F. I have a highly accurate and precise heat source to flash evaporate (dab) my BHO, and know the Bp range to my satisfaction, imo it won't boil off fast enough to take a dab at much lower than about 315C/600F, but it's definitely boiling at much lower temps. Here's what I use to generate my opinions, but anyone with a modern PID controlled lab hot plate and some high quality BHO should be able to come up with better data than you guys are floating...
http://www.tokecity.com/forums/show...zation-Temperatures-(and-ways-to-achieve-them)

 

[HashoftheTitans]

That can't be correct, you've all seen THC boil off rapidly at much lower temperatures than 420C/788F. I have a highly accurate and precise heat source to flash evaporate (dab) my BHO, and know the Bp range to my satisfaction, imo it won't boil off fast enough to take a dab at much lower than about 315C/600F, but it's definitely boiling at much lower temps. Here's what I use to generate my opinions, but anyone with a modern PID controlled lab hot plate and some high quality BHO should be able to come up with better data than you guys are floating...
http://www.tokecity.com/forums/show...zation-Temperatures-(and-ways-to-achieve-them)

I don't have a precise way of determining boiling points but I am curious if you are referring to cannabis oil or THC. I notice that obviously all shatter etc boils way faster than my 90+% isolate. Do you have THCA available to support your argument or are you basing your statement on your observation on the observed boiling of cannabis oil?

 

[SkyHighLer]

The Bp of THC here at 1440 feet of elevation (slight reduction in pressure) is definitely less than 200C/392F. That's as low as my heat source goes. I tested a small dab of plain old ordinary nugg run shatter (single solvent, run at room temp, non-decarboxylated,) and it took about 30-40 seconds to completely vaporize.

Someone buy me a new lab hotplate, and I'd be glad to give you better data... lol

Horatio says he pulls off the cannabinoids first, leaving the d-limonene solvent behind.

 

[HashoftheTitans]

The Bp of THC here at 1440 feet of elevation (slight reduction in pressure) is definitely less than 200C/392F. That's as low as my heat source goes. I tested a small dab of plain old ordinary nugg run shatter (single solvent, run at room temp, non-decarboxylated,) and it took about 30-40 seconds to completely vaporize.

Someone buy me a new lab hotplate, and I'd be glad to give you better data... lol

Horatio says he pulls off the cannabinoids first, leaving the d-limonene solvent behind.

Maybe that is how he makes his distillate, but not his shatter. I believe I somewhat replicated his process for a basic winterized Limonene shatter.

https://www.instagram.com/p/BCdjnaiRqrQ/

He has been making the shatter for quite some time. You should see what he is distilling from his THCA.

 

[Cannabliss420]

The Bp of THC here at 1440 feet of elevation (slight reduction in pressure) is definitely less than 200C/392F. That's as low as my heat source goes. I tested a small dab of plain old ordinary nugg run shatter (single solvent, run at room temp, non-decarboxylated,) and it took about 30-40 seconds to completely vaporize.

Someone buy me a new lab hotplate, and I'd be glad to give you better data... lol

Horatio says he pulls off the cannabinoids first, leaving the d-limonene solvent behind.

Again.. the BP of Cannabis Oil seems to be much faster than a 99% pure sample of THC-A. You can't justify an entirely different beast just because thats all you have access to. A crude oil containing high amounts, or the pure compound. Which seems like the most quantifiable reference point? ....

 

[thegreenman91]

Please somebody correct me if I am wrong but isn't the boiling point of THC-A irrelevant because of how readily it decarbs into d9THC.

 

[HashoftheTitans]

Please somebody correct me if I am wrong but isn't the boiling point of THC-A irrelevant because of how readily it decarbs into d9THC.

Not when discussing the possibility that Limonene has a lower boiling point than THC. When making distillate, it is very relevant. However, Horatio has shown that he can isolate THC-A and terpenes using Limonene as a solvent. Boiling point of THC is irrelevant when doing this.

 

[Roji]

Not when discussing the possibility that Limonene has a lower boiling point than THC. When making distillate, it is very relevant. However, Horatio has shown that he can isolate THC-A and terpenes using Limonene as a solvent. Boiling point of THC is irrelevant when doing this.

he doesnt use limonene for crystals or terpenes.

 

[HashoftheTitans]

he doesnt use limonene for crystals or terpenes.

My mistake, I was under the impression that Limonene was the initial solvent, followed by chromatography.

 

[Phineas Freak]

Boiling points of pure and mixed sustances are normally different.
Ex.: Dissolved salt in Water rises the boiling point of the mix. Alcohol lowers the bp.
It is somehow similar with melting points: Unpure substances have lower melting points than pure substances.

 

[River_Ramblin]

H2o creates a great azeotrope with limonene lowering the boiling point below 60c. The biggest thing is getting the ratio of water to limonene correct so that you reach equilibrium at 0 solvent. Its very easy to leave extra H2o or limonene and have the distillation stop dead and over heat your batch. That ratio of water to limonene will depend on the quality of H2o you are using and, just like bubble hash the quality of water is critical to the finished product.

 

[Phineas Freak]

H2o creates a great azeotrope with limonene lowering the boiling point below 60c. The biggest thing is getting the ratio of water to limonene correct so that you reach equilibrium at 0 solvent. Its very easy to leave extra H2o or limonene and have the distillation stop dead and over heat your batch. That ratio of water to limonene will depend on the quality of H2o you are using and, just like bubble hash the quality of water is critical to the finished product.

Great, thanks for shareing.

 

[Phineas Freak]

But I would have guessed that the bp of a water:limonene azeotrope is higher, more in the low 100°C's

 

[SkyHighLer]

Again.. the BP of Cannabis Oil seems to be much faster than a 99% pure sample of THC-A. You can't justify an entirely different beast just because thats all you have access to. A crude oil containing high amounts, or the pure compound. Which seems like the most quantifiable reference point? ....

Please somebody correct me if I am wrong but isn't the boiling point of THC-A irrelevant because of how readily it decarbs into d9THC.

So, I grabbed some decarbed oil and started playing around with the full range from 400F to 666F... there was barely a faint stream of vapor coming off the puddle at 400F, and it's still just the puddle boiling off (only faster) until I got up to my usual dabbing range (600-710F.) At about 650F, there isn't really a 'puddle' stage, the dab just rolls into the blue... at higher temps the dab is starting to react violently. I usually dab at 666F

 

[Pangea]

H2o creates a great azeotrope with limonene lowering the boiling point below 60c. The biggest thing is getting the ratio of water to limonene correct so that you reach equilibrium at 0 solvent. Its very easy to leave extra H2o or limonene and have the distillation stop dead and over heat your batch. That ratio of water to limonene will depend on the quality of H2o you are using and, just like bubble hash the quality of water is critical to the finished product.

Does water and limonene form an azeotrope? Arent they immiscible? I dont think the lower BP of a mixture means azeotrope, especially if they are immiscible.