Quite a few terpenoid aroma substances are known to be possible allergens or allergy sensitizers and several of them occur in natural cannabis. It's great that there now appears to be an accessible way of producing allergy-free cannabinoids

Edit: this post mentions several. Linalool in particular is a known sensitizer.

higher reaction time equals higher conversion rates to the more stable Δ8 isomer, if you don't mind this you could extend the time by 15-20 minutes and probably reach conversion rates that touch the 80% mark, but keep in mind that most of the Δ9 isomer that will be present at the 15 minute mark will degrade to Δ8-THC if you extent the duration of your isomerization, and it will not degrade just to Δ8 but to other cannabinoids as well, like Δ10-THC, HHC (mostly to the S isomer for Δ9 ), and of course to the stable CBN, Δ8 converts to CBN at time-exteded and high temperature isomerization methods, the outcomes are numerous, always depending on the reaction techniques and the reactants being used.

Thanks for the very useful info!

I found that the filtered solution was distinctly pink, is that indicative of predominance of any particular cannabinoid?


Frac4

it is actually, color is not a very trustful method to determine cannabinoid concentrations usually, but in the case of pink there is an exception, pink means Δ8-THC,which indicates that there was probably moisture involved, or longer duration of applied heat, oxygen also has an impact, can you describe your steps?.
edit: no intention to say that this is bad, Δ8-THC is also psychoactive and very enjoyable personally, but it is slightly less psychoactive than Δ9.

I suspected that my foil wrapping could have been better, so delta 8 is likely, thanks!

I'm trying packet in a jar with oxygen scrubbed by burning cotton method alongside a normal foil packet next bake to see what difference it makes.

This is all good clean fun

Cheers,
frac4

the color of the distillate can help determine if there is Δ8-THC present, the more vivid the pink color in your distillate the higher the Δ8 concentration.
it can also be transparent with a slightly pink undertone which indicates high concentration in both Δ8 and CBD.
also even a small percentage of Δ9 will make almost every distillate slightly or vividly orange to yellow. (always depending on concentrations)
a small percentage of CBN will also turn your distillate to orange/yellow. (Δ8 and Δ9 degrade to CBN in prolonged reaction times, higher temperatures and interestingly under high exposure to UV light)
i will soon update you with a reagent test using potassium hydroxide and ethanol to determine CBD content.

98% "homemade" Δ8:

Potassium hydroxide CBD reagent test.

To prepare the reagent, dissolve 1 gram of potassium hydroxide in 24ml of ethanol, agitate the container until complete dissolution of the potassium hydroxide, and there you go, its ready.
when CBD is reacted with a 5% ethanolic potassium hydroxide solution, CBD is converted to quinone, which has a strong purple color, so the more vivid the purple, the higher the CBD content, this method can have many applications and is really simple, you could use it for example in combination with the zeolite isomerization tek and test CBD conversion rates in different timeframes, temperatures and conditions.
google patent for the interested ones: https://patents.google.c...patent/WO2014131114A1/en
brief explanation is on page 1

Hey! This sounds amazing.

I have one question though that I hope a more experienced chemist can answer me, about physical separation...

While I enjoy edibles, this sounds like an amazing way to make dabbable or vapable cannabinoid mixtures... and I'd want to be 99.9% certain that I'm not inhaling any zeolite because that is like, bad news.

Is there anything I can do in terms of filtering, choice of filter paper, etc. to ensure that no fine zeolite gets into the final product?

the better way to separate the zeolite is through short path distillation of the cannabinoids, but since most people don't have a distillation apparatus and a heating mantle, micron specified filtration should be mentioned (not as safe as distillation in my opinion)
search for zeolite of specific micron (μm), 20-30μm will do, so if you filter the 20μm zeolite dust through a 5μm filter, the zeolite particles would be 4 times bigger than the holes of the filter, so the risk of residual zeolite in you distillate is low, the bigger the size difference between your zeolite and your filter, the harder it becomes for any zeolite particles to pass through.
keep it safe and do your own research.

This is amazing! I'll definitely try this.

Regarding the dangers of smoking/vaping zeolites, maybe i missed it but does anyone have a link? Googling "zeolite pyrolysis" or "zeolite smoke", all the results i get are about how zeolites can catalyse the pyrolysis of other things, or remove carcinogens from old fashioned smoke.

I'd like to know what the dangers are, if any, and why.

Hm, all zeolite sources I have looked at were described as 'zero to something' in particle size. I guess running through 3um filter paper multiple times should be.. okay? I guess?

The risk status of zeolite seems to be quite up in the air. There is one specific form of zeolite that is considered almost as bad as asbestos, but in general only chronic exposure to a lot of inhaled zeolite seems to be indicated as a risk on most material safety sheets.

I wonder how one would assess the risk of vaping a filtered thc/cbd isolate vs. for example smoking a joint (or spending a day in a downtown with traffic).


It's not about burning, it's about inhaling. It's stone dust.

https://www.cancer.gov/a...risk/substances/erionite
https://www.zeolite.guid...-potential-side-effects/

Ah i see. Sounds like inhaling the dust is a problem, which makes sense of course.

I wonder if letting gravity separate zeolite out of the ethanol solution, and carefully siphoning off the liquid might be feasible.

i could see a centrifuge work. i found zeolite advertised with 50 micron

A distillation apparatus would probably be cheaper though at that point, and work better.


I've seen it advertised with various granule sizes, like '20 um,' but then in the detailed description it says 'ultra fine <20um' or '0-20um', which I guess is to be expected. As a coffee nerd I'm intimately familiar with the phenomenon of being able to control the largest granule sizes, but not the smallest ones..

I guess sticking with edibles is definitely a solution, and probably the healthiest approach.

Pre-washing the zeolite would tend to reduce the proportion of finer particles, as long as the zeolite is reasonably mechanically stable. The washings can be checked for Tyndall effect dispersion by using a beam of light, although I guess the 20μm material may take a while to settle anyhow, perhaps?

I'd like to do this, the cotton + ethanol in a jar. But what kind of jar should I look for? Air tight but surely not ones with plastic under the metal lid? I bet there are ones used in labs but al that equipment is often really expensive. I have old medical bottles with grinded glass tops but I feel reluctant to use then in a hot oven.

I just did an experiment with a roughly half-quart jar, and a piece of cotton wool soaked with IPA. The oxygen in the jar was used up in less than a five seconds, and the fire went out. There was heat generated, but not in any dangerous quantity. The lid was slightly warm to the touch, and that's it.

So I'd say as long as the lid is metal, you don't need to worry about plastic coating.

Thanks!

And the temperature in the oven is also to low? I'm thinking that one could take some aluminum foil and cover the jar and then screw the lid on top of that to protect the inside from the plastic lining.

I did a quick search and found that the lining, called Plastisol. Here it says 'maximum temperature of 185°F/85°C.' but I mean everyone pour boiling hot water in jars and close the lid without issues. Or +

https://www.tricorbraun.com/blog/what-everyone-must-know-about-plastisol-liners.html

Alright!
Now I got all the stuff I needed and got things cooking in the kitchen lab.
I've not tried it yet and I have a few 'particularities' that I want to share.

I used the standard version, aluminum foil folded and not the oxygen free jar. I wasn't sure it the metal tin I had was really air tight and I also wonder what it would be with the small amount of moisture that eventually would be left in the cotton it it didn't completely burnt out.

So 1 g of CBD isolate from a friend (so I don't have any data for the purity, but works in a lab so he should know). 1 g of zeolite clinoptilolite. Mixed properly and folded.
I put a thermometer probe in the outer layer and put the package in the oven when it was near 105°C. It slowly raised and after about 12 min. the probe showed 150°C. I left it in for 15 min in total.

I took it out and let it cool. Exiting times unpacking! It was unlike what any of you have written here. Middle gray and really sticky. I tried to wash/scrub the foil with 96% ethanol and that part took some time.

Then I did a mistake. I somehow thought that I wanted to use it as a sublingual tincture and thought that about 50% ethanol/water would be good. So I started to dilute the mix (still with the zeolite in it). It quickly became milky since the cannabinoids crashed out. Oh well, I then filtered it with a coffee filter, trying to wash it out with undiluted ethanol. It's still dripping, not really milky anymore but full of the finest particles of zeolite I guess. And I can see some orange drops at the bottom of the liquid (THC?).

I think I'll try to evaporate the ethanol/water and then mix it with undiluted ethanol again.

Well, it's a start. I wonder about the grayish color after the baking. If it related to the particle size or if the different ways of 'activation' of the zeolite makes any difference. My type says "Diameter 6 µm Ground and Activated in Air Flow".