what parameters are you running at to get these THC percentages? I can’t seem to get anything over 80% THC.
Did you?
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no. I disassembled his CO2 extractor to make room for ethanol.
I hid the parts 
Edit: but I’ll tell him where they are if he promises to use them for chromatography
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Is HHC heavy hydrocarbons?
Hey guys.
I’m working with a CO2 extracted crude and am having trouble getting cannabinoids higher than 90%. My THC is sitting at 81-82 on a typical run.
Our process is to winterize the crude at 10:1 in ethanol warm and then twice at cryo temps. We then perform a carbon scrub at 40C and filter. We rotovap the oil down and then dissolve in heptane and wash with ph adjusted brine. We do two washes at 4ph, two at 9ph and two at 7ph. The heptane is recovered and it is brought over to the still.
We have a 5L full bore short path setup and an Edwards 28. We run batches around 2000-2200g to reduce dwell time. We pull vacuum around 100-200 microns… sometimes lower. We have a summit distillation key in one of David’s heads. We run a hot condenser at 155 on first pass followed by a condenser running at 30C. We run the first pass on the quicker side… stripping heads and collecting main and tails together.
We then run a slower and lower second pass, stripping remaining heads. We lower the temp on the hot condenser to around 130 when the main body kicks. We collect the main body on the second pass and then move to tails.
The results we are getting are fairly clear (not as clear as on our 2L shortpath with Chemglass head) and free of distillate stink. The oil is very stable, but the potency still dwells around 82% THC and 88% total cannabinoids. We are not getting any isomerization to D10 though we do get about 1% D8 and 2% CBN on a typical batch.
Does anybody have any thoughts or ideas that could help us bump this potency up?
Thanks!
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Looking back through the thread it seems to be as I suspected. I have run open blasted wet trim material from a twister t4 outside of work on a chinese 2L short path and come up with the same results as I have at work, but without saline washes or cryo winterization. Seems even the worst BHO crude from a stainless exhaust pipe runs better than CO2 crude from a 160,000 dollar SFE. Wish I could say I was surprised.
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He who pushes the buttons on a CO2 rig is either a god or a fool
There is no i between
And god s are rare
CO2 extraction with nectar of the gods as a result can get close to perfection thou
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Ya always my experience so i always stay away from as a crude source
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Me to 
I am a atheist
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What temp are you at in the boiling flasks? How do you know you aren’t getting isomerization to d10?
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We grow it here. I run a one man lab… I extract, downstream process, distill and fill carts.
I have a few recipes that we use. The company I work for paid for a consult when they bought the SFE… the recipe they got was garbage. Full extraction, but brown cat turds from all vessels. I have run subcritical terpene extractions and many variants on a supercritical recipe. I am able to pull a decent yield of some nice looking and smelling co2 sludge, but at the end of the day I’m not a fan of the extraction method. When you look at startup cost, maintenance cost, price of CO2 and throughput, a person would have to be insane to choose SFE. Cryo ethanol or hydrocarbon extraction would destroy what we are doing in every way possible at a fraction of the cost.
The first few distillations I ran here were warm pentane extractions in a 2L rig as proof of concept. They came in at over 95 percent cannabinoids using the same techniques that I use on the CO2 crude today.
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Lab testing. I use two labs… one who still shows d10 as a CBC spike and one who is able to differentiate. I send samples to both. We did have a run or two that were having isomerization issues. We found it was a combination of small amounts of carbon not being filtered out coupled with our final brine wash coming in at 5.9 ph. Remedied these issues and no more CBC/d10.
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Temp in the boiling flask around 205 first pass, 195 second pass.
I agree
There are a few solvents left to be
Explored ethane for sure
But none the less I have seen magic from co2 rigs
I feel it s a side extraction thingy
For those with passion and deep pockets
Hey there. If you’re using CO2 extracted crude, I imagine you decarb first. Do you do an additional decarb/devolitalization after the heptane step? After rotovapping the heptane, chuck it in a vacuum decarb reactor @ 150 for an hour with a good vac, maybe 10 mbar. This’ll get rid of the excess heptane and the low bp terps and your first pass will be way easier.
Sorry I don’t use a short path so I’m no help there. Good luck
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I do decarb this way actually. Thank you, it works well. When we were having isomerization issues I switched back to decarbing in the flask to minimize dwell time at temperature, but it turned out that was not our issue so I’ve gone back.
You were running into a lot of the same problems I used to have. What are your CO2 extraction parameters? CO2 is a unique solvent that can pull out lots of interesting things that may not get pulled out by simple cold ethanol or butane. It has been advised to me that I should run a very specific cannabinoid fraction protocol if you are trying to make distillate from your CO2 crude.
What is the pH of your initial CO2 crude + Ethanol mixture you use for winterization? I would use 190 proof ethanol, so there is enough water to have an actual pH reading. The reading would sometimes be as low as 5.5. Ethanol is slightly acidic, but not THAT acidic. One thing I never tried, but would recommend: neutralize this pH before proceeding, use a gentle base like baking soda, add it to the crude/ethanol mix until the pH is 7.0, then proceed as normal with winterization.
As you have learned, the whole heptane wash thing isn’t very useful for distillate. I have only tried it a few times, but found it gave zero benefit to my distillate. I think the saline/heptane washes and degumming thing turned out to be not very important in most cases. It was nice that people experimented with it, but anyone should be able to get 95%+ distillate from ethanol->filtering->molecular distillation (if not, please DM me for consulting help!)
So, give my baking soda thing a try and get back to me! I never had a chance to try it out myself, I eventually ditched the CO2 lab I worked in.
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The heptane washes absolutely do very little, but I did find that using brine with a ph of 7 for the final washes would neutralize the solution like the bicarbonate would. Once I did this I ceased to get isomers in the flask, but the lack of potency is still an issue. I guess the co2 parameters is going to be the place to experiment. It’s truly a flawed extraction method. For reference my winterized and scrubbed co2 crude is ~70% d9 before it hits the still. With two passes I’m only getting to 82% d9
My hunch regarding CO2 crude-> distillate has always been that there are two factors at play 1) isomerization issues due to the presence of acids and 2) CO2 is picking up a (unidentified) very heavy terpene compound that has a high boiling point similar to THC. I suspect this could be separated in the heads, but is really really difficult to fractionate out with the other “heads” garbage. This is all hypothetical, but is my best guess based on experience. When I started this thread I was working with only CO2 crude, whenever I ran a shortpath on ethanol or BHO crude it was very very easy to pull over 90% target compounds using good distillation practices. Let me DM you about extraction parameters.
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It over shoots because of the boiling points. That’s why your temps (especially with the heads). It will stay at the lowest boiling point of whatever it’s pulling. Watch the vac. You’ll notice when it’s pulling hard (jumps up) your temp will jump too then settle.
A guy I ran with back in the day would set his mantle at 200 and let it go. The vac depths, mantle and head changes would jump all over the place but always pulled pristine gold. But, this guy had done distilling for decades for essential oils. Seen him do it on multiple set ups.
Always baffled me.
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