Exactly. Saw the mini chamber and thought it could be a good way to achieve a demonstration of principles on a small scale, but wasn't sure it'd be worthwhile.


This right here is getting much closer to what I believe could be adequate for the purposes of extraction, though I'd like to see something closer to a "honeybee" method:

A quick plug of another reference here:

http://blog.makezine.com/2012/0...d-make-your-own-aerogel/

Did anyone do any experiments with this in regards to DMT ?

I've been toying with this idea for a while now and was about start a thread about it, lucky I searched first.

My lathe should be arriving this week so I need a new project to keep me off the streets.

This would be it.

I'd just like to add that many of the suggestions above don't seem suitable for this process because of the pressures involved.

Co2 becomes super critical at 73 atm which equates to over 1000 psi and the process is more efficient at even higher pressures.

We're not going to able to do this without a purpose built (or adapted) pressure vessel. That's where the lathe comes in.

For example (feel free to shoot me down on the maths, I'm pissed as a nit at the moment and the keyboard looks blury so I could have easily made some mistakes)

If a 2 inch (approx 50mm) inside diameter vessel is chosen as an example, the force acting on the underside of the lid of the vessel would be calculated as such.

Force = pressure * area

pi r squared (surface area) * pressure (1080 psi nominal)

3.1415 * 1 (radius in inches) squared = 3.1415 square inches surface area

3.1415 * 1080 (pressure) = 3392.82 pounds

So that's well over 3000 pounds of force acting on the underside of the lid on vessel.

We haven't even considered the forces acting on the walls of the vessel, this could vary considerably with vessels of different design especially different heights.

For a home made apparatus, a small diameter vessel would be the best shot.

We haven't even considered the pump yet, getting a pump to reliably deliver 73 atm of gas is going to present some real problems. So the idea of using solid carbon dioxide for charging and subsequent heating is starting to look very attractive.

I'm hooked on this idea !

cool idea -

to extract freebases you would need to wet the material with base first, then dry, no?

Also, how do you know alkaloids are the main substance soluble in super critical co2? It seems like a good solvent for many things in plant material.

viewing window? I'd be more inclined to automate it as much as possible and bury the device in cinderblocks/bricks/sandbags while its under pressure.

I'd expect raw plant matter to contain alkaloids in their salt form so basifying would have to be done at some stage. Basifying before the extraction would most likely be the best route as it should eliminate the need for hydrocarbon solvents. That being said there are options for basifying after the extract.

I can't say for sure what the CO2 will extract, there isn't a great deal of freely available information on the topic in regards to what is soluble in SC CO2. My preliminary investigations seem to indicate that non polar molecules are soluble in th SC CO2 so I'm hoping it will be a similar profile to a xylene extract.

It could be more selective I just don't know. Maybe some of our chemists could help here ?

A sight glass rated for boilers/steam should take the pressure, but I tend to agree with you and would most likely omit that from my prototype. I don't know what would be so important that it would need to visually monitored anyway. I'd prefer to monitor the process with thermocouples and pressure gauges.

I was thinking of the safety of the operational procedure for the device too, I certainly wouldn't want to be near something like that in the event of rupture/failure.

Any pressurised gas has the potential to kill. I know a small leak in a dry/superheated steam system can easily cut a man in half. So to run such a device it will certainly need to be safely contained in something resembling a blastproof cabinet or buried. The device will also have to be designed to be fail safe (if it fails it will fail safely) and have an excessive safety factor carefully calculated in the design phase.

This type of device is beyond the scope of your neighborhood plumber or backyard mechanic and I wouldn't consider building this without consultation from an engineer with hands on experience in high pressure applications.

Don't try this at home kids.

I highly doubt it.

for starters, butane extraction, at least with the method you guys are thinking of, is not a supercritical fluid extraction.
also, DMT has poor solubility in short chained aliphatic solvents; applying heat or high pressure (hence, SFE) increases solubility.

OK I'm starting push the boundaries of social etiquette here with all this rambling. It's one of my pet hates when someone dominates a forum with their own fantasies. So I'll make a few minor points and let this go until I have a working prototype.

I was looking into the idea of basifying before the SFE and it seems that an aqueous solution could cause some real concerns in regards to foaming, and could contaminate the extract with non polar molecules and all sorts of junk. So I'd rule that out for now.

It seems the efficiency of the SFE is significantly enhanced by the addition of solvents to the extraction vessel. Ethanol and Methanol are two that seem to be almost standard in many extractions.

I find it interesting that such solvents are used given their polarity, so I need to do some reading to understand their function in SFE.

Wow!

Love the idea.

Definitely a project that could be attempted with a decent metal lathe, or mill, and design the pressure vessel way beyond overkill.

As this is a non-trivial bit of engineering, it has to be meticulous regarding safety.
Ideally you would operate the device remotely. A simple processor, minor programnming, I/O with appropriate sensors would be nice. Not too hard anymore...

But those pressures!

Actually this may be a pipe dream, but damn it would be interesting as all fuck!

DP

I have renewed interest in this topic, and have come across these interesting blogs. I may try my hand at this going into the new year.

http://jyndustriez.blogspot.com
http://skunkpharmresearc...able-diy-co2-extraction/

A few questions ---- >

From what i understand you want to use liquid CO2 to extract things . The " advantage " is the high preasure involved = The peasure breaks down the cells so that the extraction is more " efficient " . = its only for very skilled and knowledgable people with a LOT of money and time that want to extract big quantitys ?

The dangers being the fact that CO2 is deadly and ...... the preasure ?

SO ---- >

Why not freeze / thaw the substance several times = The cells get brocken ....... then put the shreded substance in a stainless steel tube ...... with dry ice on the top and seal it ...... as was done in the 70s to extract cannabis . At the bottom is a hole to let the goods out ?

Or a step further = with a preassure gage on it and a preassure switch = that when the preasure gets to a certain ........ not dangerous level ........ it opens and lets the gas / goods and preasure out = The preasure inside the tube comes from the dry ice turning into gas and getting warmer = you have the same solvent and the same ...... or very nearly the same results and not the expense . the work , the time and most of the danger .

If not why not ? Disadvantages and advantages of both please ?

has nothing to do with lysing the cells, so freeze/thaw is moot. supercritical carbon dioxide permeates plant material and carries biomolecules with it. this is how coffee is decaffeinated.

i'm looking at it from the aromatherapy p.o v... it does not thermally degrade fragrant compounds.

the disadvantage, as you mentioned, is cost. the equipment is somewhat expensive..pumps, backpressure regulators, etc.
carbon dioxide isn't terribly hazardous; i'd rather work with that than butane, where any random spark could potentially win you a darwin award.

OK . @ you and everyone ---- >

So its not the breaking down of the cells its the preasure ? Or is liquid CO2 a better solvent than dry or gas CO2 ? = Is it more efficient ? If so how much more efficient ? = Is that efficiency realy only theoretical ? = The difference for a personal fantasy example between getting 90 % out in 5 minutes instead of 7 minutes ? Or the one way gets 93 % and the liquid way gets 95 % ?

Are these " efficiencys " realy efficient / worthwhile when we think about the difference between 93 and 95 % after considering the work , time , money and danger ?

And what about what i sugested ? ...... is the liquid way realy more efficient than doing it how i said ?

is it a "better" solvent in liquid form as opposed to gas? of course...
you learn in general chem that molecules in the liquid phase interact more closely than in a gas phase.
carbon dioxide has unique properties in the liquid phase. it readily dissolves amphipathic molecules, and carries them out of cell membranes, like dmso...but evaporates in seconds.

relative efficiencies are just that... relative. what do you mean by efficient? save time? money? energy?

there are advantages and disadvantages to every technique/method. you first need to
determine what your end goal is, and consider every option at your disposal.

given the option, for the purpose of extracting, say, psilocin or dmt, I'd certainly consider a liquid CO2/hexane mix, 60/40.
that sort of extraction may even be carried out in subcritical temp/pressure. the trick is carefully monitoring/controlling temp and pressure.

Thanks for the good explanation . I didnt do chemistry at school .

Part of what i am trying to point out is what you said about efficiency . The other part is the efficiency in this case = What is / how big is the difference in the results of extracting with liquid CO2 in comparison to CO2 gas and CO2 gas under preasure ? For example 1 kg of P.Viridis leaves containing 2 % DMT ? A trip ? 5 % ? = If we look at it from that direction does it make sense ? What return / improvement are we going to get for how much money . time , work and risk ?

Is it worth it as compared to what i said = CO2 gas under preasure ?

I am not expecting exact answers for my theoretical questions from anyone .

you probably won't get impressive yields from gassing the plant material, for the aforementioned chemistry reasoning. Solubility is negligible/extremely low in a gaseous state. however, as a liquid, it acts similarly to methylene chloride, yet it's nontoxic.

keep in mind, it depends on the compounds being extracted... there are reports of successful extractions of CBDs at subcritical pressures, which would mean CO2 was in a dense gaseous state.

the systems mentioned in the links i posted can be used at critical/subcritical conditions, but they are open loop systems (no solvent recovery).

BUT ....... then i think of butain extacts with cold gas ( yes yes diffeent solvent with different qualitys ........ but not THAT different ) ...... and the fact that CO2 extractions of cannabis useing dry ice or CO2 gas were done and talked about in books in the 70s and 80s .

I want to point out possible weaknesses , improvements and perhaps different ways of going .

I understand that most of what i want to know ...... and what i think people should think about when they do things like this ...... is theory because its very hard to do any reliable expeiments because of the unsure legal status .

Cross thread and subject thinking ---- >

The subject has interested me for years and also maybe the posibility of extracting psilocybin with gas ? As the only other sensible method i can find is useing ethanol . As i said the results of useing just methanol and evaporating that off produces a yellow slime mixed with lumps . That then needs cleaning to get a white result = Much to much for me at least . The methanol came from a chemists . He told me that one cant buy pure methanol or ethanol because it has a small % of water in it because it is hygroscopic . I read that the strongest ethanol for exsample is about 95 %= When the methanol is evaporated off it leaves a small amount of water and other things besides psilocybin ...... and thats what the yellow slime is . < ---- thats ment to be part explanation , part defence and part me asking questions to you and other knowledgable people .

Gas if it works with psilocybin would be fantastic . The results a dream product . Would it work ?

I never got yellow slime.
https://www.dmt-nexus.me...aspx?g=posts&t=17734

that was rotovap'd.

the SC CO2 method could be promising, especially with hexane in the mix..it's great for recrystallizing.

Thanks . I licked my lips . Smile .

" that was rotovap'd. "

Maybe thats the difference . My rotovap was the top of a cupboard in a dark room .....

I know THC/CBD are not alkaloids, but there seems to be a lot of Co2 extracted Cannabis concentrates, at least in the CA MMJ markets. I have sampled some of it, but I do not like the taste, flavor, consistency or potency compared to shatter, budder or thick oils/waxes made from other solvents. Does anyone else feel the same way about Co2 extracted Cannabis concentrates or have they had some good ones?