At this point I’m not even asking for particular methods, just trying to gather data about what is or isn’t possible.
That looks like a significant research project there. Each one of those would have to be tested individually then as a mix with cannabis crude oil to see how it behaves during distillation. Some may not even survive distillation intact but instead break down under the heat into other compounds. SPD itself is a pretty blunt instrument when it comes to distillation. If it was me doing the research I would opt for a fractional distillation unit like spinning band. It would be an interesting study, I’m not sure anyone here knows whether it’s doable or not.
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It’s doable but a few days work for each. Also you have to decide what concentration of pesticide to use. Some techniques that work on low ppm don’t work on high ppm.
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I was able to do enough tests, in 2017, to determine everything other than PBO, Pyrethrins, and Permethrin are susceptible to having their concentration levels altered through the singular use of, or combinused use of these medias [either in normal or reverse phase, GRADIENT BASED, TRUE form chromatography!!!]: (Silica, Magsil/Florisil, C18)
I had success with various of the 100’s of spiked samples I played with, using a LLE process involving a heavy salt water at various PH’s. These washes really remove ALOT of contaminates other than fats/lipids. But you need to understand what pesticides you are dealing with, do you backend research on them using toxicology/lab data, and then approach removing them in an appropriate way.
I can even remove Permethrin and Pyrethrins with ease, using an expensive/proprietary reverse phase media. PBO is able to be removed too. Just picky to what absorbency/binding properties your media has, and what solvent systems you use.
Wish everyone actually learned classical chemistry. The way everyone else does ‘chromatography’, isnt true chromatography. You’re meant to load your sample on an equilibrated column first, and then pass the compound through the column using a specific gradient of solvents, at a ‘strength’ to target a specific compound to elute from the output in a specific fraction. Using a UV wavelength derector and a sightglass lets you seperate fractions.
I will not state how to input solvents at specific gradients, what equipment I used, what medias remove what, what PH’s dissolve/transfer/degrade what pesticides, etc…
My consults are not cheap, but results are always seen.
Recently finished a build of a custom chromatography skid, capable of gradient based elutions; parts cost was less than 10K, and it’ll process a few dozen KG a day, easily. This was inline to a nearly automated washing station, with stock tanks for various PH water solutions, etc…
Have done numerous of these consults and installs for various gigantic facilities, @Future and a few other verified consultants can vouch for me.
Photos available, but only shared as a reference and when trust has been established.
Username used to be something different, used to be pretty well known on these forums. 
I can travel to all 50 states; traveling cost, and daily fees apply.
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Can you elaborate when you say magsil alone with saline wash before will remediate it? Thx
Mix a batch of like 60gal of water with salt. As much salt as you cab put in it. Split that into 3, 20 gallon containers.
Then for 1 container, mix some citric acid in and lower the PH to around 3ish Ph.
For another container, raise the Ph to 10, by mixing in Sodium Hydroxide crystals. Make sure you dont go too high on the PH, too high and it will dissolve the oil into it.
Then you have one container thats not mixed. Thats your neutral.
Figure out how you wanna wash, either small scale with seperatory funnels, or larger scale with a glass reactor or something like that.
Use whatever SOP you have for liquid liquid extraction then.
Magsil in any type of chromatography column will work. Glass, stainless, plastic, etc… this should be done after your LLE process. An easy way to use magsil is with just heptane/hexane, alone. Either your extract is still in heptane/hexane, after the LLE, if not dissolve it now.
Equilibrate, or prewet your packed column by pouring some clean solvent into it, slowly, until it passes through the bottom of the column. It helps to settle/set the media and gets you a tighter column packing. It will often show you areas of possible channeling, before ut effects your actual process.
Once the columns ready, follow the chromatography SOP from someone you know that has one posted on here. Theres a few, im sure of it.
Magsil alone will remove it. After the saline washes at those various Ph’s. Its really quite complex, and theres alot of small details im leaving out that must be addressed during the process, for it to work.
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Don’t discount some of the people on this forum…
Hey Future, Do you believe a 2:1 distillate:media mass ratio is most useful with pesticide remediation?
Has anyone performed LLE with hexane/methanol regarding this PBO situation?
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Go for it. You’re assuming PBO should be more soluble in MeOH.
You can get some remediation of PBO without this.
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oh snap, great read. Definitely something I’m going to use.
@drjackhughes the safety data sheet says that it is soluble in methanol so if this regular remediation does not pass this week I will be attempting reverse phase with methanol
Fatty acids will not dissociate in an acidic aq. solution. In alkaline environment fatty acids are fatty salts (anionic fatty chain + cationic metal) therefore; dissociate. Acting as soap molecules
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Yes I have done a redemption of PBO using LPE and Chromatography column. I used Heptane and a 3 part saline solution 4,9,7 . Then magsil- pr column . I also used T-41
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That pink color in your image can be gotten rid of. The red line is harder.
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Would I do a PH 7 saline wash then re-distille
See DM.
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Is there any benefits to doing a heavier blend with the heptane (4:1 instead 2:1), or would it potentially effect the process in a negative way i.e the blend being too thin and the pesticides passing through the column quicker?
Negative in terms of chromatography. Might bring up your yields.