Testing the waters to see if anyone has had experience removing Abamectin and Spiromesifen or had any ideas on how to accomplish the task. I have looked though the remediation threads and haven’t really found any information on removing these two pesticides.
Abamectin:
water soluble(Low): 1.21mg/L
Heptane: Not Soluble
Boiling point: 940.9±65.0 °C at 760 mmHg
Spiromesifen:
Water soluble(low): 0.13mg/L
Heptane: Soluble 23g/L
Boiling Point: 531.1ºC at 760mmHg
I have not started on the material but the biomass tested at 0.925ppm abamectin and 0.014 Spiromesifen. just to place it safe I’m assuming a 15x concentration once extracted putting me at 9.25ppm abamectin and 0.21ppm Spiromesifen. I plan to remediate in batches of 10L at a time.
10L of disti should contain
Abamectin: 92.4mg
Spiromesifen: 2.097mg
If I water washed with 55 gallons of distilled water per 10L . I should be able to pull 251.68mg of abamectin and 27.04mg of Spiromesifen.
That should solve the Abamectin issue but I don’t think it will solve the Spiromesifen issue. Ill be using 2:1 ratio of heptane to disti. 20L of heptane will hold 460g of Spiromesifen.
Other Possibilities to remove pesticides
Using a Nomograph I calculated that Spiromesifen will boil at 217.6c at 30 microns and Abamectin boils at well over 300c. That would lead me to believe that if I keep the distill under 200c that those pesticides should remain in the bf unless it co-distills at at lower temp with THC or something along those lines.
I have also looked into using magsil pr but it does not look like it does the trick for these pesticides. My math might be incorrect so please double check. Definitely not a professional chemist.
That’s the typical response that I have but the grower has been a great client and I’m taking it as a challenge to better myself and my companies abilities. As an extractor we need to bring as much value to the farms as possible.
I hear you! I was more joking than anything to be honest, I apologize. Sometimes I can’t help myself. It’s like Tourette’s, but with stupidity… There’s a couple different remediation SOPs around here, and I’m sure some more knowledgeable people will chime with time.
in theory I think more water washes would work for something like abamectin since it is not soluble in heptane but barely soluble in water but I think it would be beating a dead horse if you are trying to LLE something that is soluble in both. Especially when the carrying liquid can hold 10x what the waste liquid can hold.
Looks like for Abamectin there is a study out of Egypt that is specific to using ozonated water to as a liquid wash.
If I was going to try to do this - I would probably start with a general carbon scrub, then MagSil, then a brine wash. Expecting to remove a bit at each stage. I might also consider general chromatography - the literature on Abamectin development indicates that chromatography and SPE was utilized effectively for separation using ACN, Hexane, and salt water. There’s also a study that indicates that it hydrolyzes within about 12 hours - then you might be able to get it out using acid/base LLE washes.
For the Spiromesifen - there’s another study out of India - this covers degradation patterns under normal conditions for growing plants. This indicates that it readily degrades in the presence of sunlight and water. There’s information about it hydrolyzing as well - so doing aqueous washes may also work but may take extended periods to be most effective. Its also known to readily dissipate in soil - which leads me to believe going with a carbon scrub would help facilitate removal more quickly.
Aqueous LLE with a carbon scrub sounds like the best option here. And then you just need to get your distillate dry (there are many methods, pick the one you like the best). <3
Let us know what ends up working for you so we can all learn from your experience.
I believe that you can remove both of these pesticides using magsil Pr or silica 60.
General rule of thumb for determining similar pesticides:
When the 66 pesticide mixtures are sold to analytical labs theyre sold in my experience as 4 separate mixtures. 3 of the mixtures contain all the pesticides remediated with magsil or normal phase chromatography
1 of the mixtures contain all the pesticides too fat soluble for normal phase chromatography
This isn’t a perfect rule but it is generally something that can guide your R&D towards something that works.
I have 180kg of crude with those exact two pesticides. Im glad i randomly stumbled across this thread. Ill throw em in the wipe film and run a test after.