Solventless Terpene Extraction


Why are you under that impression?


Viscosity issues, mostly. I suppose if you only pulled the low pressure fraction for it it might.

The terps are advertised as full spectrum though, and I know not all of the terps come out in that first fraction, implying the entire terp fraction is being isolated.


I only said ethanol cause that’s what I do
I can def do inert gas stripping on co2 extract and I don’t know y u keep saying it’s not big enough scale they do huge scale gas stripping in other industries


You are on the right track considering there are terpenes that even boil hotter than THC, but I’ll suggest that you control the temperature of the oil to keep its viscosity down. With the system under reduced pressure and with a stream of inert gas, there shouldn’t be any serious alteration to the flavor profile.

I suppose by “low pressure fraction” you actually mean the “volatile” or “high vapor pressure” fraction. Correct me if I misunderstood, please.
Check into what Shadownaught suggests. I almost bought a benchtop lyophilizer for the purpose a few years ago, and I still kick myself for not running that experiment. I had soooo much tasty oil at the time. Now it’s mostly distillate… :frowning: By slowly raising the temperature and keeping the oil in a state of relatively low-viscosity (via heat) I see nothing wrong with the process. As a matter of fact, I’ve been telling people to do it since before I ever extracted oil from cannabis. They still look at me like I’m crazy… Like it’s too simple to believe…


you can i can also make them using a cold trap on my co2 machine. I only partialy recover my co2 and I noticed the venting co2 definitely still smelled strongly and i tried it and it worked just not very much could be collected


yea me too lol you can also combined vacuum and inert gas stripping to minimise degradation. that is what that link i posted was saying, it talks about doing it with cannabinoids which means you can def do it for terpenes and with terpenes the pump wouldnt have to be that powerful


I can see why @ExTek90 might have concerns for upscaling the inert gas stripping, in that there are surely some heavier terpenes or perhaps acid esters and all sorts of aromatics that would be much less costly to extract with something like steam distillation than with nitrogen gas (and I do understand that you stated steam distillation was not the process you were speaking of). But in these instances, perhaps the quality of the product extracted under inert atmosphere gives it more value? Or does it not? What do you all think about steam-distilled cannabis terpenes vs. CO2-extracted terpenes vs. whatever you have tried that is high in terpenes but lacks cannabinoids?


yes but from what ive seen the benefits of steam distillation have little to do with steam thats why hydrodistillation isnt nearly as effective and inert gas stripping has very similar results. altho its not talked about much things can “dissolve” in gases like steam to a small degree and since h2o is a good solvent it often strips compounds better then inert gases that have no attraction to what they r stripping but this is a small factor in cannabis cause most terpenes r hydrophobic


In fact steam distillation can only work with organic compounds that are hydrophobic. Steam distillation cannot work with water soluable organic compounds.


I have done steam distillations of extract and terps.

From observation I believe it does not matter much what gas you use to strip terpenes or really any part of the compound that is volitile. By this I mean that water vapor as steam works great but also blowing a fan across extract is pretty effective at releasing at least the pinene. My nose tells me so :see_no_evil:. Evaporation below the boiling point occurs with all liquids at the surface. More surface area equals more evaporation. Crumbling my crude into small chunks makes it smell stronger because of more surface area.

Blowing a gas through the liquid compound increases the surface area exponentially because of the added surface area of the inside of each bubble. Depending on temps there will be more evaporation of volitile liquids. Fresh gas moving through the compound gives fresh surface area and volume continuously for volitile liquids to evaporate into and the newly evaporated volatile gas is carried along with the bubbles and out of the compound. It is just another way to accelerate evaporation and it is really mechanical in nature as I view it.

Bubbling a fish tank bubbler up through solvent also speeds evaporation dramatically for the same reason but it will make the remaining solvent colder.

Steam works well simply because you need a LOT of gas passing through a liquid compound to speed the surface evaporation this way. Furthermore steam introduces necessary heat which overcomes the enthralpy of evaporation of the volitile liquids from the compound as well. An inert environment might work well if it was designed to recycled the gas in some fashion but would be prohibitively spendy otherwise. Steam is simple to implement but has water purge issues on an epic scale. An inert gas would be great if the gas didn’t cost anything to run except you would have to pump it through at pretty high velocity to match that of steam. The equation has to do with how fast you can create new surface area through the compound me thinks. :nerd_face:


But are we really just after terpenes? I find it hard to believe that a true, full, cannabis flavor profile excludes hydrophilic compounds.

There are definitely a few slightly water-soluble compounds listed here for example, with solubility even over 500 g/L in water. Is the water from hydrosol really clean of any aromatic compounds?


The water will become saturated with the volitiles at the ratio published. The water is not clean at all normally. It is actually a good thing. The extract has to get pretty hot to begin evaporating a lot of pinene. Lots of steam will pass through until it hits this point. You will see only clear water recovered in the condenser until the system begins running well. Pinene is clear until it mixes with water. It is only slightly miscible in water but a little bit turns the water white.

You will see the water begin to drip white and cloudy when the system hits running temp and a high enough steam flow rate. Simultaneously you will begin smelling a potent scent of pine tree in your entire lab…very potent. The white water is a visual marker for pinene which seems to come off first on the extracts I get.

The pinene that does not absorb into the water is clear and extremely odiferous. Generally I spot it as an oil sheen on the surface of the water and likely other terps are there too but pinene really trumps the scent for me.


You are correct about the CO2 fraction. I understand the process of inert stripping pretty well, just haven’t had the oppertunity to try it.

Part of the viscosity issue I mention, is stripping the terps that come out of the entire extract, hence full-spec. Additionally I’m not convinced you wouldn’t pull at least some cannabinoids in that process, these products are tested 100% cannabinoid free (unless they’re cheating, I doubt it,) cannabis derived.


For my purposes, yes, I’m just after the terpenoids.


This is a bit of an older thread but I found this on reddit and it seems relevant:


@Sapes Is this a home built short path? Note* esp when he said heat and change gas to liquid , and short path better he said …just curious…like short path for plant matter?


I have been reading this patent and it is fascinating. I note it is granted in 2012 but filed in 2002. Are you aware of any equipment that has been developed based on the patent? I did not see any in my searches.


What would your thoughts be on;

Inert gas strip - collect
Subcritical co2 soak (800-1000psi) - collect
Thc extraction (ethanol?) - collect

then combine the three fractions?


My guess is If You use your cls rig in revurse You have a pretty decent pressure proof (50psi )
Steam/inertgas unit😀


I suppose that would work well as far as making a product providing you used subzero ethanol, that’s a lot of handling the material in different ways though. It certainly isn’t scalable.