What happens when you distill a distillate over and over again

As the title says, What would happen if you take a 86% THC Distillate and reprocess it at same or slightly elevated temperature, using Wiped Film. Forget Diminishing returns, I want to understand the chemistry. Does the potency increase or decrease, what about other cannabinoids. I would assume a slight increase in CBN each time. Is there a plateau it will reach

Run 1 - 84% THC
Run 2 - 86% THC
Run 3 - ??

How do you imagine it would decrease?

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Degredation from prolonged exposure to high temps can happen. You get cbn and crackdd molecules.


Umm. What temps you cranking? Cannabinoids are quite robust to thermal degradation. Oxidation and UV not so much.


Even at 190-210 C under vac can lead to cracking if you distill the same load over and over. Some users have reported loose, bright yellow and low testing oil from distilling a single load 5+ times. Also only talking about SPD, not WFE.

You’re correct though, thats why you dont see a lot of degredation on a few runs other than CBN.


After how many passes does it turn into fenty. You could get a pretty sweet advertising deal once you crack that code


You’re saying if one were to run distillate over and over through a wiped film at the same parameters, what would change in the final distillate? Normally each pass would be performed at different temps & vac levels to evaporate different molecules, and that exclusion of compounds based on differences in boiling point & vapor pressure influences any changes in potency the most. The goal is to evaporate any lower boiling point molecules first to remove them from your oil, and then to rerun the oil and evaporate only the cannabinoids, leaving any higher bp molecules and non-volatiles in the raffinate.

I’ve never just reran the condenser fraction back into the feed at the same parameters over and over hoping for increased potency, sounds like the definition of insanity to me.

In my experience you don’t get much CBN increase from the wiped film run itself, as the residence time at elevated temps is not that much.

Yep you are correct also the residence time on a regular short path is measured in hours and on a WF is measured in single minutes at most and so while thermal degradation does happen on a WF it is virtually insignificant for all intents and purposes. “All things being equal” and if done correctly each successive pass (up to a certain point obviously) should give you a purer end product. But at a certain point you should take into consideration the “law of diminishing returns”.
Just my little bit of logic before the coffee kicks in and I get motivated to start working. :wink:


On a SPD I see stuff get worse after two passes personally.


How so and why do you think that is?

Probably because his first two passes are so well tuned in that a third is the point where there’s not a worthwhile benefit. Props to those that have the magic figured out. My guess is that’s from fine tuned experience.

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That’s awesome that you can do that but that’s not what he said.

And considering that thermal degradation is close to irrelevant, your comment does not seem to pertain to what he said.

I was thinking that maybe if he’s using discharge pumps he could be having problem with oxidation as the hot distillate pores into his collection vessel but this too has a very simple solution.

Edit: generally speaking you should not be losing purity by adding theoretical plates.

I implied he or his team were that caliber and capable. Nobody else, including my own skills were implied. Fuck hanging around with a heat gun and watching flasks boil. Not my style. Big fan of those that can get shit done.

Wipers are something I have more appreciation for at this point from personal experience. Spd is still very much a learning curve that I could never compare against anyone talented here on. It’s not my cup of tea. “I was just implying wow, two and done.”

I get that bro but it does not apply to his comment. He was not saying he does not see benefit, he was saying he wasn’t seeing losses, which is a very different thing.


Carry on. I’m lost I guess… makes sense to me based on the talent speaking. Not the general audience.

Don’t give me too much credit I’m just an idiot trying to keep his head above water. I just try to pay attention to what people are saying and understand what they are actually saying not what I want them to say.

Second pass in the SPD routinely hits high 90s total cannabinoids. More than two and I’m losing some yield and destroying cannabinoids needlessly. Just a long time to be under heat even in a no oxygen environment. Could be fixed by vacuuming deeper but when it’s not broken there is no budget to fix it these days. Wouldn’t really expect the same results in a WF


Oh, okay, well that’s a whole different story. I thought you were talking about WF.

Long time to be under heat?

What temp is your oil at before it hits the still?

Typically the residence time at max temp is on the order of seconds to minutes in a wiper or rolled film. No reason to have high temps anywhere else and the time it takes to travel from still body to evaporator is minuscule.

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One thing for sure. The propensity to oxidize increases each time IMO.