I detect a pattern of misinterpreting what I’m saying beyond what I care to repair. I regret saying anything.
I understand the advantages of Acetone vs ethanol from chemical extraction standpoint.
I don’t understand the relative solubilities of ALL the pesticides one might run into as a tolling facility.
If you know that everything on CA’s list is extractable with Acetone (I certainly don’t), then you’re correct, acetone is at least as good as ethanol for a biomass prescreen, which is what the OP’s question reads as to me (although not eating cheap plastic tubes seems like a win for etoh to me…)
I have certainly run into pesticides that extract with Ethanol but don’t seem to come along for the ride with Butane. I’m simply generalizing that empirical data and asking the OP if that’s what they’re up to.
I’d love to understand what your point is. if indeed I’ve missed it.
or, we can await the OP’s response and leave the guessing for more important things like winning lottery numbers 
Edit: appreciate the DM @eyeworm. we are on the same page now…
5 Likes
I have done a lot with acetone. Only use high grade acetone, and the extraction is very similar to etho.
Boiling point is lower, so it comes off faster.
Not much too it.
3 Likes
inexpensive disposable extraction vessels:
https://www.google.com/search?q=falcon+tubes
which won’t work with Acetone…
bifenthrin, for example, is soluble in Acetone and only slightly so in methanol.
one might posit that it would also be less soluble in ethanol than acetone.
one could certainly argue that in this case extracting with Acetone would provide more information.
or one could argue that a clean micro extraction with ethanol would bode well for a production run on the same material.
We have experience with acetone. Here’s the thing, if you use a solvent that doesn’t represent how much your extraction solvent concentrates that particular pesticide, then if acetone under concentrates a pesticide there is the possibility that it will be an ND (the labs are permitted 30% error margin, and still get certified by Emerald Scientific). So when you go to extract it could end up showing up.
Another consideration, you typically pick up more material in an acetone extraction, so the pesticides that concentrate in acetone or your extraction solvent will appear diluted as compared to your actual extract.
I’m a fan of the extraction done with the extraction media, but we’ve never tried it. Theoretically, I’d use the exact same conditions as you’d use to run your material.
This part of the process is not my favorite. From time to time there are false positives and negatives. Cross contamination is always a worry.
Also, if you run hydrocarbon or CO2 this presents a challenge…who has a small extractor just for micros?
2 Likes
OCO labs has your itty bitty CO2 covered.
I’ve still got my iitty bitty glass tube from my earliest R&D
2 Likes
Good to know. Let me put you on the spot now, where do you fall on the micro debate?
- Original extraction conditions
- Super solvent (acetone, DCM, etc)
1 Like
I’ve let @drjackhughes put me on the spot…
now where do you fall on the micro debate?
- Original extraction solvent
- Super solvent
- huh?
0 voters
You want to do cryo acetone.
1 Like
Interesting. Explain.
It’s nearly the same as etho. Get it cold. Super cold. -78C. You can do 5 minute washes w/o the need to winterize.
2 Likes
no I did apply to them though lol
Thank you for your input no answer is a bad one in my opinion. I really just enjoy hearing other opinions.
Basically I make A small RSO sample to send in to get tested for Heavy metals and pesticides. I understand that ethanol would possible be a better route but I like how acetone will strip the material at a faster rate. I was thinking possibly a small 2L roto but then I was thinking about cleaning that thing each time and got discouraged at that idea.
This thing looks really cool. I wonder what the yield is like and if this machine would strip the material of heavy metals and pesticides more than a larger CO2 system?
This is only for RSO to be sent to labs for testing.
I guess I always focused on a clean RSO w/o fats and waxes. An extraction that doesn’t need winterization.
Acetone works great. I would consider using it again if I could.
Calling it “RSO” intrigues me…
because it means different things to different people
I don’t know that Rick ever suggested Acetone.
Given he suggested Naptha, who knows.
I’ve also got a local producer that is calling an almost pristine 70-75% cannabinoids cyro-ethanol extract “RSO” because that’s what folks have heard about on the internet. So they buy it.
I get that you’re sending it off for testing. In reality the lab needs miniscule amounts for actual testing. They always ask for more than they actually need to perform the analysis at least a couple of times.
How much are you making, vs how much do they ask for?
How big are the biomass batches you’re sampling?
Are they in-house or external?
how you sample lots that might not be homogeneous is going to affect your false -ve/+ve rates.
were it me. I would extract in 50ml falcons. 5 gm biomass. with ethanol.
taken as 5 one gram samples per 15lb batch (METRC batch size in OR, last time I looked)
I’d use a speed vac (vacuum/heated centrifuge!) with one of these rotors
Lab Evaporators for sale | eBay to remove solvent. capture in matching savant cold trap.
but that’s just me
2 Likes
Notice the end of the clamp has been sharpened for use as a cork-borer. Probably for my first cold trap. Or at least the first one I had to cobble from scratch.
Edit: newly installed in my electric car. A 2011 Th!nk. As an inside joke around the dangers of internal combustion 
(and sharp objects)
3 Likes