chromatography without banned solvents at home

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

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I'd like to use chromatography in California safely without anything they consider a solvent. Per specific cannabis law, they don't consider ethanol a solvent. There are a few other exceptions possible, and would like to hear more.
I've done a crash course of sorts on chromatography. Home processing for oneself is acceptable, but any use of volatile solvents* is illegal in California. *The California legal definition of volatile solvents in the section on manufacturing specifically lists ethanol as an acceptable non-solvent. https://cannabis.ca.gov/applicants/lice ... ense-types (type 7 license for solvents, type 6 for no solvents, home for oneself is like type 6) Taken as an exception, no other solvents can be used. But taken as a limit of volatility, it leaves open the use of anything less volatile than ethanol.
Not mentioned anywhere related, bottled terpenes can be added when processing cannabis oil and terpenes are non-polar solvents which liquify cannabis oil at only 5% added. Terpenes sold as such should be defensible. D-Limonene bought as a single chemical is more likely to be considered as a solvent. Paying more for the same chemical (limonene) appears more defensible. What do you think of these 'solvents' and what others would meet the intent of California's law?
An acid would be useful for refluxing to clean and isomerize oxidized components (CBN -> THC, CBD -> Delta 8 THC). The acid must be removed without depositing undesirable salts, unless of course the salt can be removed before adding sample to solvent. Hydrochloric and acetic acid appear to fit, but I found 'pros' may use sulfuric. What acid should be used at what maximum concentration?
A brine wash would reduce/eliminate chlorophyll and contaminants. Coconut oil (and others) is non-polar when virgin, but apparently polar as distilled MCT (medium chain triglycerides), which would be useful if they can be removed. Do you have a way to remove them? Are there any other solvents, buffers, augments, or anything else that can be used while meeting the legal definition? (I'm not asking a legal opinion, but a chemistry answer that I'll research the law later)
My intent is to figure out all the chemicals that are allowed and useful, and determine an optimum solvent system given limitations. Terps can be the non-polar solvent, alcohol as the polar non-solvent*, and add a polar solvent to (not quite) equilibrate the column for another batch. I'll use sodium hydroxide, but not for every sample. Does this sound right or should I adjust my thinking?
Cannabis oil can be cooked indefinitely at up to 100c, as it gets limited to with water, going through decarboxylation at about 24 hours. Above 100c, it takes 15 minutes to decarb after water is driven out. https://pubmed.ncbi.nlm.nih.gov/28861498/ There is no degradation after many hours at 110c, or vacuum refluxed indefiinitely. A finished oil for vaping cartridges should be mostly decarboxylated. I have no reference for these suppositions so I may have introduced error. Terps (all essential oils) can be removed at the start and reintroduced, but that's another subject. Cannabis oil can be cooked a long time. The water wash can be done repeatedly before adding solvents and separated by chilling and pouring off the water. Since solvents* are not allowed at home, the water wash stage is needed.
I was going to short path distill, not sure if I can following all local laws, until I discovered chromatography will serve my needs. While I may get to where I'm identifying and pulling out individual molecules using TLC on my fractions, it isn't really necessary. Like a distillation, I only need to remove the heads and tails; as in the most polar and least polar molecules. Cannabis oil has color, so no UV needed to determine what is happening. For good material, you don't want to remove anything more or it ruins the profile. For poor material, it still amounts to eluting near pure THC with high tolerances. As a hobbyist, I can afford time inefficiency. I can combine and concentrate samples and run them again for greater resolution. My time and labor can be wasted in this endeavor. Material cannot.
As an aside, an owner of a large production lab (not cannabis) explained how he uses a dozen cheap shop-vacs and crock pots instead of a dozen RotoVap stations. I'm sure they capture most of the solvent first. So even in California, the alcohol can be completely eliminated.
For personal safety, my biggest concern is Silicosis. Lacking a fume hood, I'll pour silica gel wearing a gas mask, outside where it won't blow toward anyone. I figured I'd pour it into a glass jar, add ethanol, put on the lid, shake, and then hose down any silica outside that jar. Will this be sufficient protection? Does a column need to be run in a fume hood, when used with... ahem, legally not solvents?
In researching columns, and multi-columns, I conclude that a two column system would be useful, especially with a tiny volumetric pump to adjust the column's speed. Would it be correct to say that a 10mm tube, 100cm long would introduce mixing? I found used Luer connectors for 6mm OD tubing to 24/40 which suggest they exist, but found no other examples. What glassware and connectors would serve this purpose?
I am a legal medical marijuana patient in a state where recreational use is legal. My opinions are my own. I do not promote any illegal behavior. The topic of this post is how to proceed while obeying all local laws.
What I usually do when I have a booth at the conference is bring a bottle of vodka and vinegar. This creates EtOH/water/Acetic acid mobile phase. Make sure that your vodka does not have any colorants or additives.
Vlad Orlovsky
HELIX Chromatography
My opinions might be bias, but I have about 1000 examples to support them. Check our website for new science and applications
www.helixchrom.com
Once when doing extractions on broccoli seeds I had a client bring me a few bottles of Everclear which is pretty much 98% Ethanol to use for the extraction procedure.

Distilled White Vinegar should do nicely for the acid just as Vlad mentioned. That would make everything essentially a food instead of a solvent.
The past is there to guide us into the future, not to dwell in.
Vlad Orlovsky wrote:
What I usually do when I have a booth at the conference is bring a bottle of vodka and vinegar. This creates EtOH/water/Acetic acid mobile phase. Make sure that your vodka does not have any colorants or additives.

I did not know you responded until now, sorry.
I found using silica outside with a gas mask was too sketchy, so I stopped. i ordered alumina but haven't opened it yet. Silica + ethanol turns into a concrete mess.
I also went through a few iterations of glass and gear; this has been a hard journey alone. I'm just messing with my own, so there's time between experiments. I'm ready to tackle this again.
I will try "a bottle of each" vodka and vinegar for in situ ethyl acetate as suggested, thanks. This rides that fine line very nicely.
It appears boiling off under vacuum or degassing doesn't remove the last traces of alcohol. What would you recommend to clear the last traces? I may use limonene instead, or after to remove everything.
Will this produce any side products that require another step to clear?
I'll use TLC to figure out my best combination and gradient. Any suggestions on that?
Limonene is a non-polar solvent and a terpene common in uplifting cannabis, so it is okay to leave a trace. It degrades to just isoprene (I think) and is pretty easy to deal with so far. Limonene appears immiscible in ethanol. Limonene can be removed a few ways, and a trace amount doesn't hurt. Other terpenes could be used.
Any recommendation on how to combine these elements is welcome.
I can see I'll take a few more months just to do what a lab could do in a week, but I'm not in a hurry. I'm open to recommendations.
I switched to DCVC (dry column vacuum chromatography) but still made silica concrete a few times. I found a claim that alumina and ethanol work well with cannabis in DCVC.
So you could use denatured HPLC ethanol?

We needed to develop an assay for a consumer product (OTC drug) containing 5 active ingredients. Of course it was desired to have the separation be fast/isocratic and complete a cGMP validation, and be thus amenable to use at our QC facilities.

I tried to use conventional solvents like methanol, ACN, THF, etc., experimented with different buffers, columns, temperatures, etc., but results were less than desired.

I settled on a mobile phase using denatured HPLC ethanol as the organic, full well knowing that the denatured HPLC ethanol contained about 5% methanol and 5% isopropyl alcohol. Well, at first, my pointy-haired boss had a fit, believing that the denatured HPLC ethanol would not be a pure substance, so how can we depend on the supplier to deliver consistent product? Anyway, boss relented, came to believe that supplier did QC to ensure methanol and isopropyl alcohol levels were correct, and we did cGMP-validate the procedure and did use it with zero issues.
I found this untenable and unsafe, and stopped. I honed my related skills and will be professionally continuing these trials with 'tracked and traced' cannabis oil. I'll have the same rules I anticipated, and have two cameras on me at all times from two government agencies. There are too many profitable lab projects that I'll get to do, that won't need a fume hood nor chromatography. As we'll be specializing is a range of CBN products, oxidized "Crude" cannabis oil extracted with hydrocarbons is a fine starting point, and chromatography would really help before distillation.
Dry column vacuum chromatography (DCVC) using <something allowed> in alumina seems my best way forward. I tried and failed to use limonene as I can't get it out by distillation and burned limonene is the worst possible mess. A trial of MCT (medium chain fatty acids) was a mess, though I should try again. Caprylic acid, octanoic acid, marketed as "C8 MCT" aka brain food in mother's milk (great marketing) boils at 240C at 1atm. For products that are not smoked, this seems ideal. I need to do more research to see what percent caprylic acid and its side products are allowed in cannabis distillate for vaping.
I bought "alumina dessicant" which are large beds, and a cheap 3A Zeolite which are ~3mm beads. What should I try in chromatography?
Would caprylic acid (with some ethanol as determined by TLC) work for (dry or wet) chromatography, and what media should I choose?
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