I am interested to know if it’s possible to distill directly from dried buds or sugar leaf. I am thinking of trying the following experiment :
Putting the plant material in a round bottom flask in a heating mantle, starting at room temperature.
Pulling a high vacuum on the flask, with a cryogenic colld trap between the vacuum pump and the flask
Slowly increasing the temperature of the heating mantle, and collecting the terpines and cannabinoids in the cold trap.
Hopefully I think that the terpenes will come off first at room temperature, followed by cannabinoids at 100c or less.
Please let me know if this will be a waste of time, because I don’t have much experience of distillation. My reasoning is that the low pressure will lower the boiling point of the cannabinoids to 100c or less.
This will almost certainly be a waste of time. People have a hard time dealing with crude oils hitting 65-70% THC… you’re gonna be nowhere near that with flower and you’ll have way more lipids and undesirables to deal with. If you do end up experimenting I’d be curious about your findings. I just can’t see it working well…
Give it a try for the sake of research, but as already been said, you now have more material to have to separate as fractions than if it had been extracted first. Also, since you have more material in the flask, you are going to cause all sorts of surprise reactions between the thousands and thousands of different chemicals in the flask, and probably cause some strange isomerizations of cannabinoids. You will most likely be left with a considerable amount of biochar on your flask.
Was this what Shiva Processing was proposing at some conference a while back?
I tried a version of this in a few different ways. The problem is the enormous volume of smoke and solid debris generated during thermal breakdown. In other words lots of smoke and sooty tar and black. I even threw out a flask rather than try to clean it hehe. It is possible to recover a bit of cannabinoid doing this but the mess is horrid and I doubt a cryo trap would be able to trap the smoke particulate from entering the pump and fouling the oil.
Also, something about removing the oxygen and then breaking down the plant material sans oxygen seemed to produce some chemical smells that seemed toxic almost. Perhaps a chemist type knows what happens with plant solids heated until decomposition in a vacuum?
There is a techinque call dry distillation, used for extraction of wood tar. I think it’s a way to recover extra useful product when making charcoal from conifer wood. Sounds very crude and dirty.
It sounds like you tried this under vacuum. Does the vacuum not help reduce the boiling point of the cannabinoids enough not to need harmful temperatures? Perhaps a higher vacuum would help, like what a scroll pump would produce.
The boiling point of all liquids that I know of is reduced with reduced pressure. This is the core of the idea here. The problem starts first with the fact that generally the cannabinoids are entrained within the plant material. If the compound turns to gas at 120C at a reading of one micron which is typical of the single plate distillation I do in a sublimator then it will remain gas so long as the temp and pressure remain constant but then how does the gas escape the plant matrix? The answer is the matrix must be removed or destroyed for the gas to escape.
I tried a lab once in which I buried the extract in aluminum oxide and then sealed the sublimator to try to run it. My theory was that the cannabinoid would turn to gas and migrate up through the alumina and would discourage contaminates. It did not work and just made a messy lump of alumina and extract but burnt. Lowering pressure might help but the reality is that down below ten microns the point is a bit moot because down that low there really is no system pressure as a practical matter.
Here is the archived photo of me trying this. I had to recover the burnt compound using solvent and washing the alumina.
Nothing really made it up to the cold finger so that month my med supply was… @Photon_noir tell me again what the scientific term for “really gross” is?
Just mix like 2:1 kief with lab sand with no solvent and agitate, that might actually be worth it…But with only biomass? A whole lot of wasted energy in heat and vacuum to perform a separation that could be performed mechanically without distillation. Isn’t that why rosin presses were invented?
Back in 2010 I first experemented with this preposal, my results were never that great. Some of the main issues are : Particulate matter that can deposit on the coldfinger, and condenser reflux back down toward the plant material.
the picture shows the first way I ran the apperatus, with the condenser above the reactor. It was plagued with reflux issues, I had a sidearm adapter made for it that would offset the condenser, and allow the liquid falling from the condenser to collect in a rbf. The entire project was a messy pain in the ass with heat transfer fluids and low yeilds. I came to the conclusion that the resin was extracted better with hydrocarbons. It’s a novel Idea tho!
I have done extensive work on this, you can do it with a controlled nitrogen flow through a packed and heated column. Connect the exhaust to multiple condensers, at different temps to drop out the compounds that turned to vapor.
I can say that it it did produce a golden oil fraction with lipids, but efficiency issues with my prototypes caused lower than expected yields. Still, it should be explored more.
Issues that needed solving are:
A more efficient condenser, the vapors are like a cloud and not like distillate vapor in a short path. Because of the nitrogen, it is highly expanded.
I had trouble condensing the vapors and it did condense in a pinched tube in between 2 dewars at -40°c
Heating the column, you need to hit 240°c and preheat your gas to this heat as well. I figured this out in a few ways, but it still had issues as all prototypes do.
Scaling the apparatus so the yield is actually worth the trouble is another concern of mine but it can be done. Or running higher percentage biomass.
If anyone wants to make a serious go at designing a system and working with me on it i would be interested, i have built 2 variations and have valuable input.
Nice! Seems the question I posed in the similar thread on doing this in vacuum ovens applies here: anyone tried fresh material?
That way there’s lots more terps to hopefully azeo over cannabinoids lower, not to mention the water ought to help some evolution of the desired compounds, or at leadt theoretically
How about using this technique purely to extract and save terps that would otherwise be lost during an ethanol extraction? So vacuum purge out the terps from the plant material, then do the ethanol extraction, then add back the terps to the extraction. Can anyone suggest what pressure and temperature to do this at?
I would start with an ln2 cold trap inline with the best vacuum pump you can find. Start at room temp and ramp up, watch the cold trap for condensation.
