Will a pesticide carry over to isolate

Hi everyone,

I was wondering if anyone knows if a pesticide (specifically bifenazate) would carry over into isolate?

We have some distillate that is testing around 160ppb for bifenazate and I was thinking that I might turn this distillate into an isolate and then remediate the pesticide from the mother liquor.

Any thoughts are appreciated.

Cheers,
-Kyle

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Not sure. I’d pr before trying to go to isolate just to be sure.

I have some 3rd party tests out for pesticide on the isolate so I’ll know for sure soon. I was just looking to see what people think is going to be the outcome, or for anyone who has shared a similar experience. Thank you for the reply though, your insight is appreciated.

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Try a small scale water wash at various pH. If it works at the small scale, a reactor is a small investment in regards to future preparedness for such events. Realistically you just need the cheapest reactor available to use as a large sep funnel.

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Thank you for the reply, I also tried to a pH wash of our distillate. We diluted our oil 1:2 oil to heptane and did an acid wash followed by a base wash followed by a neutral salt wash then ran it over a Büchner funnel with Silica 60 loaded on it over a filter (loaded as a slurry). We have also sent that sample in for testing and will be getting the pesticide results for that soon as well. I will update this thread with our results, I am hoping for the best.

Have you ever tried a similar method with successful results?

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Ethyl acetate looks like a good choice for recrystallization solvent.

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Would CBD crystallize in ethyl acetate?

Do you think washing the iso with ethyl acetate would help?

I dont know how you intend to isolate intially, but what i suggest is that once you have your isolate you REcrystalize in ethyl acetate. Bifenazate should stick around in the mother liquor. Some mother liqour will be caught up in the crystal structure as it forms.

It will definitely dissolve in ethyl acetate, which means of you evaporate the solvent slowly you can cause crystals to form. Im not too sure about washing the isolate with ethyl acetate, if you did so it would need to be very very cold. Not worth it imo but maybe ln2 can be be used

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Hi I just wanted to share that the isolate came back pesticide free.

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What did you end up using for your reX solvent?

Pentane

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I have done this many many times. Recrystallization is the most general and reliable form of remediation; doing it enough will get rid of anything.

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Bifen you can do a LLE with ACN (acetonitrile) and Heptane as they aren’t miscible. The ACN will grab the Bifen.

Mix oil with ACN,
add equal part of heptane (enough to capture all of cannabinoids)…
dilute with RODI water — heptane is not miscible with water — this dissociates the cannabinoids from the ACN.
Discard and properly dispose of ACN/water layer.
Keep heptane/oil layer. Recover heptane, test oil

Problem Is that most people’s skill level to handle ACN is questionable and no residuals are acceptable because ACN converts to cyanide in the human body.

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I haven’t tried but in theory high pH hydrolysis would work as well
At the very least you could use this as a protocol for disposal.
Your ACN/bifen/Water — swing pH to 9 or higher for 2 hours or whatever the time (have to double check if that’s isn’t at 50% steps or completed at 1.6hrs — check for UV décomp too you could add that in). That might make disposal easier or better
—I would look but “spoons”.
:call_me_hand:

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What initial ratio do you use for your Oil:ACN?

How much water do you generally add to cause the full cannabinoid disassociation from the aqueous layer?

Shouldn’t having no residual ACN be as easy as fully separating the organic layer from the aqueous layer? To be safe give it 48 hours under high vacuum in an oven?

Thanks for the reply it is very much appreciated!

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Read the SDS on ACN and yes there shouldn’t be any in your heptane