I recently started using my SPD again. I have a 5L lab society set up, I think maybe the G2. I have a -105c cold trap and a pretty large pump i think 13.2 Welch. Sorry im doing all this from memory right now otherwise I would be exact with everything.
Anyway, I recently ran some decarbed THCa mostly for R&D and I wanted to make sure it was fully decarbed. The COA before distillation showed 13% thca still. The stuff was beautiful after distillation absolutely water clear. Then when I took the system apart and air touched it everything turned purple.
My cold finger is consistently at like -24, my vac in main body is like sub 20 micron, mantle never went above 205 and head temp was steady about 180 to 185 I mains.
Ive done a brine wash, with acid and base to try to correct PH, I ran the finished brine wash through sodium bicarbonate to make sure ph was good… still purple.
Ive done a hot scrub with b80, w4, and magsil… better but still purple.
Also, it seems like the purple is like thermochromatic. It gets extremely purple when heated up. (I had it in my vac oven at 250) then got back clear when it cools down except for the top layer
Im going to try a second hot scrub tomorrow but im just wondering if im missing something or if its just purple forever.
I’d recommend getting a COA to check if there’s any d8 in your product. A few years ago when I was still learning my boss was doing experiments with T-41 and we managed to make purple disti with the intent to make d8, but that’s my only experience accidentally creating purple disti.
Also, search bar is your friend. There’s a few threads about purple disti that might help you out.
Hey I appreciate the feedback! I’ve done some searching thats what prompted me doing the brine wash to attemp to correct the ph, but perhaps I overlooked something, I’ll dig in more.
No worries, glad to hear you’ve already done some legwork. But that’s why I recommended the COA to narrow down the possibilities for your discoloration. Good luck!
Thank you, I’ll get some COAs and post them. After further research it appears it could also be rapid oxidation due to high purity d9 having little or no antioxidants. Heat seems to increase the oxidation speed and vacuum also appears to create purple streaks or bubbles.
Seems like the solution is to mix the purple distillate with some “liquid diamonds” that still contain some THCa so that we can get some antioxidant protection and decrease the likelihood of the purple oxidation.
Ill finish my second hot scrub, brine wash/ph correct, and mix with a little liquid diamonds and report the results.
Hopefully this works lol. If anyone has any other ideas, this is all basically R&D at this point so I can do some stuff and report back.
I’ve never ran a short path, but if your cold finger is comparable to an internal condenser -24 sounds too cold to me.
Not sure if there is any relevance to the purp. However, I am unsure if too cold here could possibly cause excessive reflux and thermal soaking in your boiling flask causing heavier noids to fall back in resulting in potential conversions/overheating material.
Your thermochromatic (chromophore?) description sounds pretty specific & might indicate the washes/ph swings. Did you only wash after it initially went purple. Or did you wash the material originally?
Take a small amount, dissolve in pentane or heptane 10:1, and do a saturated ammonium chloride wash and see if the colour disappears. If it does, your THC distillate is alkaline. If it, doesn’t it’s likely oxidation.
Can I ask - why distill decarboxylated THCA? If the THCA was quality it shouldn’t have needed distillation after decarboxylation
Thank you for the advice. I’ll definitely give it a shot.
We mostly did it for R&D. I have a customer that doesn’t like “liquid diamonds” so my thought was to distill it and it would just be high quality distillate. I didn’t anticipate the purple issue. Lol
The cold finger, not sure if thats the technical name or not, is at the end of the SPD and condenses terpenes.
You make an interesting point about the excess reflux and thermal soaking. My liebig condenser is normally at 120f to 130f im using bucket tech right now. But my room is fairly cold (60 ish) so that could contribute to excessive reflux. Ill try putting some foil over my head and see if that makes a difference.
I washed it after it turned purple. I got the liquid diamonds from another lab so I didn’t make them or decarb them.
What is the customer’s issue with liquid diamonds? Distilling won’t add any cannabinoids or lipids to affect viscosity, assuming that is their complaint. The liquid diamond manufacturer may have intentionally left some THCa behind or added THCa to reduce discoloration.
So the first issue is too light in color. Apparently, their customers don’t like almost water clear carts. So they tried adding some distillate to their liquid diamond to make it a bit darker but then got some kind of separation where we are assuming the liquid diamonds and distillate didn’t mix well.
So anyway I don’t have a ton of information other than that… and even that doesn’t make a whole lot of sense to me but just trying to get the people what they want. Lol
I start to believe that feu to new techniques and extraction methods might have something to do with this
extraction by means of salting or at least
Accitic cannabinoid x base reactions are upcoming some big prossesors are implementing this and that the cleanup is faulty and some base is left in the thc-a
The first reaction is a acid chase reaction often straight forward and fast
But to clean this up we use a double displacement reaction that is straight forward yet not equally fast and defenatly has some parameters that influence the yield of reactions
If the final washes are not preformed correctly and preffaraby a recrystelization is not done
