I wasnt sure how to word this for a search inquiry. I ran some first pass and then ran it as second pass. the distillate from the second pass still has the slightly funky smell that comes after first pass. Can i just run the second pass again without effecting the THC too much?
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I have done 3 passes before, but I find that the third doesn’t change much except for a bit more degredation. If the oil has a good color to it, then I would try just sticking it in a vac oven at 180F for a couple hours, that removes the smell for me. If there are still some un desireables in the oil though (it has a darker color, maybe some of the green heads before the THC got through both times) then the smell may return though.
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How much it will affect the THC depends on how long the run is, how hot it gets, and how strong your vac is. more vac less heat more degredation, more heat less vac more degredation.
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My SPD is different than most. I also can easily detect the funky smell on my second pass stuff. I find that a third pass is always necessary to fully get past that off flavor.
However it will be ineffective if you are running the same temperatures. Each of my runs (typically I run three passes) is set progressively lower in temperature. I have found this to be necessary to really get good separation. When I used to only run one temp I found that the third pass made little difference in removing the off odor. I also found that heating mantle temperatures exceeding about 165°C tended to make th eproblem worse. I attribute this to reaching the smoke point of the oil mostly but also that at this temp there is enough extra energy in the system to pull up those trace compounds that taste so gross.
My third pass protocol in fact usually has me setting the mantle temp for 150°C nominal with a system pressure of one micron when I am shooting for isolate type purity.
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I would think a carbon scrub would kill it. But who wants to do that if you don’t have to. I have been finding that if you take your time around 180F, probably lower on other systems, like 150 or so, that it barely has a stink after the first pass. I am still a newb myself, so I would listen to these other people here with more experience.
When I was at Summit, I talked with a guy who ran some stuff 5X trying to get rid of some red. He seems to claim it was still usable product.
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yeah carbon would work, but a funky smell means that you cut your main body fraction to early. next time let more main go into your heads fraction. Also, if you pour into a beaker at a moderate temp, then whip a bunch of air bubbles into it, then stick in vac oven and pull vac, those air bubbles will help pull out the smell
I found that if you run first pass , decarb at 140° c till bubbles stop , ramp up to 160° -170° pulling this nasty fraction, greens and such, wait for fraction temp to crash Then drop heat back down to 160°, stop stir, remove vacuum , swap out nasty flask with new one QuickTime and revacuum , start stir re heat back to 180° and you should have nice gold fraction coming in, if you like the clarity rotate collect to about 200° to 205° or color change in vigreux and fraction temp crash, rotate to tails collection. After you are finished take main fraction heat and stir for 5min just enough temp to melt, put in final collecting vacuum at 25hg for couple of hours you have no smell and clean mains!
This is a single pass, trim washed at-°40, 1hr soak scrubbed with 1tbs mix /per gallon bvv carbon and celite545 mix , then filtered , recovered and distilled.
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Interesting. You do the scrub in the original volume of solvent? I always hated the idea of rotoing it down, then scrubbing, then rotoing again.
I assume you not not doing a hot scrub.
Yes I add this to starting solvent, cold wash, cold filtered, -40°c at all times
Also, I find decarbing in my 2L is a nightmare. Need a couple pieces till I get my 5L up and running.
So for now I transfer it and decarb in open atmosphere, then transfer and to boiling flask and go.
Any tips here?
I have 1 tip here. Pack the column. That shit seems to work. Same theory here as alcohol. I am starting to think I should remove the summit key and just pack as high as I can.
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I’m seriosuly torn between a silvered V2 head from Lab Society, or a jacketed, non-silvered packable head for my first still. I mean, when I started distilling alcohol I’m glad I started on a pot still before I built a reflux column. Same concept?
I just got a thermal head from summit that is packable. Should help me change make even better product.
what do you guys use for packing? the glass rashig rings or the little expanded metal ribbon bits?
I have the silvered V2 and for the scale of our opperation its great. Not the fastest distillations, but the separation is well defined.
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make sure you leave a space at the very top, maybe a half inch below where it right angles to the condenser. You only want purified vapor here, the small gap helps keep fractions separate.
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