Hello Everyone,
I have an urgent question for the community. We have some oil on hand that is testing at 169ppb for bifenazate.
I was wondering if any of you had any advice on how we can remediate this out of the distillate.
In addition to advice about how we can remediate this out of our oil. I was wondering if there is anyone out there that has the capabilities to remediate this out of our oil ASAP.
Thanks in advance for all of the help.
Cheers,
-Kyle
Bifenazate06.pdf (572.5 KB)
From this data it looks like dissolving the extract in heptane/hexane and partitioning with a methanol/water solution could give decent results.
Get the oil nice and dissolved in heptane. Citric acid w/ph ~2. Wash 3x. Neutralize,
If bifenazate is still detectable, rinse and repeat.
Would the bifenazate partition into the methanol/H2O or into the heptane? Probably the methanol and the water correct?
Thanks for the reply, What would you recommend as our acid? Also what pH would you try?
Take a second to look at the data that i posted, solubility in hexane at 20c is 230mg of bifenazate per liter of hexane. Solubility of bifenazate in methanol is 45g per liter of methanol. Taking into consideration the very low concentration of bifenazate and the insolubility of methanol in heptane is what made me suggest methanol/non polar partition. But cannabinoids will be slightly soluble in the methanol/water mixture so i suggets trying @Ruwan suggestion first.
@Ruwan what concentration of oil would you recommend in the heptane (g/ml)? Also should I separate the phases before neutralization?
This is a fantastic publication. I’ve tried LLE with hexane and acetonitrile buffered with acetic acid per this publication before and had interesting results. Took the idea from the section where they use acetonitrile to extract the bifenizate metabolites from animal fat. Water would work fine though, and have better health implications if any trace solvent was left behind anyways.
If you are feeling crazy and don’t want to do it the easy way with LLE, exposing to light rapidly degrades bifenazate into non-detect compounds (like as shown in the previous paper posted). Cannabinoids slowly degrade as well, definitely not as fast as the bifenazate.
My old LED lights brought a gallon and a half of 10:1 ethanol solution from 75 ppm down to 3 ppm in a couple hours. Mad scientist stuff.
So what was so interesting about your results with the hexane/acetonitrile LLE?
Do you have any lights that you would specifically recommend? You said you did it with a 10:1 ethanol/oil ratio?? Thank you for the reply!
Do you think that a LLE would work with heptane and water?
What’s your opinion on the acidic wash followed by neutralization?
It made three well defined separate phases in my seporatory funnel. I was not expecting it.
What were the constituents of the phases if you don’t mind me asking?
Try a light source that is in the visible spectrum. The brighter the better. I just happened to have some LED grow lights on hand at the time from a previous project. I’ve tried pure UV and did not have much success. 10:1 is what I did because it was performed immediately after winterization and that happened to be the ratio after that process. I’m not 100% sure if this played a role, but the ethanol was denatured, 90% ethanol, 5% isopropyl, 5% methanol (weird I know, but great for winterizing).
I’m not sure about heptane because I don’t have experience with that solvent.
edit: From my understanding of the publication and hands on work, use of acids converts the bifenazate-diazine to bifenazate. I wasn’t sure what the solubility was of diazine and the publication stated that it could be converted back with acid.
Top organic phase: most of the oil
Middle phase: trace oil and most of the bifenazate and bifenazate diazine.
bottom aq. phase: acidic water and some bifenazate and bifenazate diazine.
Was the acetic acid modifier in your acetonitrile pure acetic acid or was it a solution of acetic acid and water?
From my understanding of the publication use of acids converts the bifenazate-diazine to bifenazate. I wasn’t sure what the solubility was of diazine and the publication stated that it could be converted back with acid. I think it was a solution 5% acetic acid plus the acetonitrile for extracting the pesticide out of cattle fat.
Do you know the DOI of this paper?
Thank you very much!
