Red color during short path

Anyone know what this may be? The potency is very high in THC but the red throws me off!

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I personally think it’s CBN.
Based on looking at a couple of Beaker’s sublimation runs on my GC yesterday.
see pH balancing THC distillate (quick oxidation/color issues) - #20 by Beaker


I think I found the reason MY distillate has been sub-par. Anyone have any clue how I did this?

I thought of that, CBN is rose color. But I keep my boiling point well below the CBN boiling point. I am running under 170C to get my flow… but still. CBN is the only thing I can find while searching. The CO2 crude was winterized at -60c for 36hrs then double filtered.

without protection, the makers of synthetic THC found that THC oxidized/degraded to CBN at room temperature. accompanied by a color change. Stability of dronabinol capsules when stored frozen, refrigerated, or at room temperature - PubMed

excluding oxygen helps after distillation.

running at lower temps reduces production during distillation.

getting the pH right after any washes or chromatography doesn’t hurt.


they also found it can be stopped if stored in vacuum or inert atmosphere at 0 f

When the seal broke a fragment was trapped between the scroll passage. Upon the next oscillation of the scroll the seal debris was trapped, something had to give. My guess was it was eroded by it’s own debris, first innitated by the bad seal.

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sounds legit. lack of yearly tip seal replacement.

[equivalent to not replacing timing chain in infernal combustion engine at appropriate interval & smashing valves with pistons when it gives…]

thanks you!

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Just to be clear.

I was not attempting to derail this thread with a dead vac pump post.

I’m 100% convinced that the damage shown on the pump IS the reason my SPD runs have been sub-optimal. (read: "dead vac pump == red distillate in MY case)

The pump we switched to has also been beat to hell, but I found a brand new one in a box yesterday…only min after being shown the damage to the Agilent above…so things should improve from here.

At least until somebody figures out that I stole the vac pump from the EtOH recovery still we’re putting together :wink:

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No problem. Great vac is the key to high potency. If I get below 400 microns I am consistently hitting 90% or higher first pass


1011mg/g is cannabinoids?

doesn’t leave much room for anything else…

I believe if the color seems to separate from the distillate, it is more than likely a pigment like anthocyanin or possibly carotene. I lean towards the former considering I have seen it in high quantities coming from “purple” strains. @anon42519203 uses a condenser at 155c to allow the red to bypass his collection flask.


That’s one of the fun capabilities of the BR spinning band, real time condenser temp adjustment (from computer attached PLC) for selective bypass to cold trap.

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I’d like to play with a SB but went with the 3 stage WF instead. I have an obsessive issue with batch processing that I need to get over. I’m looking forward to using it in July-August and will post results.


If you are doing 3 stage WFE, other forms of distillation might just slow you down.

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3 stage Wfe system what do you mean

Some say that degumming can remove this effect. :sunglasses: I haven’t tried myself yet.

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I find the red color can be scrubbed out in a couple pre washes and might show up if I push certain batches to a higher than normal temp . In the begining I saw it alot.

I see the red bad any time I go over 200c in the boiling flasks

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