It's not Methanol?! A Theory for Medusa, part 2

In part 1 some details regarding amine sweetening and merox treating of LPG were highlighted. This all began after initial discussions and theories were based on potential of hydrogen peroxide ppm being a possible cause, but it pertained mainly to the material not the solvent.

There was a strong likelihood in our minds that the solvent was causing this “feature” to occur, and so we began taking a look at the refineries. Originally we thought potential contamination from residual ppm of Isobutane could be the reason as it was the only other substantial residual commonly found within packaged solvents used in our industry. That was not it, so the search continued.

We identified a highlighted interest in Ammonia mainly because it was also already established as a potential candidate as per @Roguelab and @Photon_noir indications.

Throughout the process flow we saw Merox and decided to get into that a little more.

TL;DR

After the community was able to correlate a matching theory:

to our independent research;

We dug deeper, and learned about some considerable key factors. Mainly that; as per many of @moronnabis comments in various discussions on this forum, pH plays a very key role since Amine’s are salts. Its likely that a lewis base is required within a wash, and this is exactly what the Merox and its regenerative processes do, I am no chemist but what I think folks are missing is that you don’t need very much of this stuff to create a chain or continuous cycle of reaction (correct me if I’m wrong).
Amine Removal From Aqueous Process Streams by Ligand Exchange…pdf (7.9 MB)

Opportunity crudes
As the environmental and geopolitical landscapes shift, and we work to change our energy supply sources. The actual sourcing of input crudes will vary more and more and thus opportunity to utilize the “perfect” amine cocktail in LPG treating cheap sour gas from a cost perspective will result in these changes with the butane and propane used in botanical extraction.
neutralising-amine-selection-for-crude-units.pdf (554.3 KB)

^^^ This guy knows what’s up and can explain in technical terms for those that are savvy, and if were lucky he can chime in and kickoff the conversation. But, what I am here to tell you is this; we kind of think the addition of a tertiary amine may have occurred since 2020 and continued sporadically with different supply channels and other things like the Bakken plant being back online, etc.

I believe but perhaps am confusing myself that in my prior reading of many papers there was mention of tertiary amines not being removed but actually neutralized. I think that basically means there is a “liquid salt” in residual that is neutralized but possibly becomes “active”(?) when interacted with carboxylic acids.

It’s Not Methanol?!
We think that methanol can be used for transfer pipelines, and in liquid containers, so it seems more like a common byproduct of the handling and shipping procedures. We also don’t think a primary amine is root cause since they have been used prior to any noticed changes in supply line. We think the only variable would be the addition or removal of a tertiary amine solvent, that is if the amine theory is correct in general.

By the way, @Dukejohnson is a very good dude, glad to have met him in Toronto. I’m not in any way attempting to discredit his thread or any of the work those folks have attributed towards discovery and providing solutions for “Medusa”.

Shoutout to @Graywolf, @Zack_illuminated, and others! for working with us on this stuff.

Please feel free to provide your thoughts, and or any input. I don’t claim to know exactly that this theory is correct, its just a theory.

Sour Gas = More Salt, too much salt, more than the refineries care to try and beat up their equipment removing so neutralized amines are better, but they can react with carboxylic acids?

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Definitely several amines and several oxygenates at play in all the gas and they all have their own effects on the crystallization. Rami been saying he may make an account here to share some of his newer findings.

You must have me confused with someone else though. I’ve never been to Toronto and we have never met. :call_me_hand:

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pH only has meaning with water. So while the THCA may be exposed to water in the trichome during development, and that may determine protonation of that moeity during the extraction, subsequently not so much.

Not saying protonation/deprotonatkon doesnt occur, but just that it has no link to the auto dissociation of water into OH- and H+ (which is what pH is). So different theory and different rules.

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Really? Wow thats embarrasing. Okay sorry. We’ll be in Vegas.

Yes exactly, and water is used in Merox treating, but at what pH? That number is specific to the amine cocktail used? Not talking about pH in the LPG, more or less talking about how pH washes affects amines?

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I have a few questions. Why does Medusa only happen in the cold? Why not in rocks that were crystallized hot? Why can’t it just be a polymorphism issue?

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My belief; is that heat causes more lipids/wax’s which entomb the THCA, versus cold which would leave those molecules more exposed?

I have tried only thca and butane. No sauce or Terps involved. Still I see the same results

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Things can crystallize differently in regards to shape and geometry of the rocks depending on the Temperature or pressure in which they are crystallized. Many compounds have different polymorphs depending on the crystalizing conditions

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Exactly…different sets of rules…or models.

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You have water with merax, which determines the protonated/deprotonated form of those moeities at that point. Just as with THCA in the trich.

But when the two come together it has nothing to do with pH when/if they react. That’s my only point.

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My apologies, it isn’t so much that pH is the “cause” but a solution to removal of amines, and thus hopefully we’re able to identify how or why the “solution” works to deviate a “cause” from there?

Isn’t it that our attention should be focused on carboxylic acids (THCA) with amines? Rathen “pH” so to speak, I guess pH speaks more specifically to the downstream washing part of the process? But is that not a place to start and work back from?

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pKa’s are still a thing in protonated organic solvents IIRC and organic chemists are the keepers of those gems, not me.

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9 -9.8 pka are amines of interest

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This is an excellent article…and all who are wondering what amines may contaminate your Butane…and WHY that may be a mixture of amine-compounds that continually change…. A
MOVING TARGET…read it…

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I think he’s focused on your usage of pH because that implies somehow that water is involved. It might be involved later - but on the column when cold its not involved.

So you need to be looking at the pKa values of the amines (or whatever impurity…) and their interaction with the cannabinoids in their acidic (and non-acidic, honestly) forms. And I think that @Roguelab is probably right about the ranges…I would probably be looking from 9.5-10.5 but that’s just me.

We could be considering the temperature differential that @Waxplug1 mentions - why does this only happen in the cold? Why not in recrystallized hot THCa? Is this an issue with crystal structure?

When I consider why this might only be happening in the cold… and I consider the presence of these potential impurities that you have outlined… that leads me to a couple of hypothesis, that I wish I could test myself.

*Because they are cold the amount of carboxyl groups available for reacting with each other is limited, so those that are present allow reacting with impurities for longer amounts of time. there is an experiment with alka seltzer on the internet for kids, which shows this. the reaction is slowed down by things being cold. the reaction would happen very fast at warm temps - boom and over. but at colder temps there is an opportunity for other things to happen. So consider that both reactions are always happening. But that in one case temperature has one reaction happen so fast that it uses up all the available starting material before the other reaction could be noticed.

*its possible that the impurities degrade as well at higher temperatures. therefore partially or completely removing their ability to react with the carboxyl groups that become present. this happens to lots of impurities in lots of things (think pesticides and what not) where those things are degraded just by the presence of heat or light and then create new paths of impurities. those impurities are still there they are just so minimal that it is hard to notice them.

At this point - the impurities would need to be removed with water washes and what not. Which is what it appears many people are already doing. You could do this to your gas (with special equipment) - and maybe some suppliers are already doing this.

Back in my lab days - I used to handle amine removal by creating non-soluble salts using ketones and then filtering those off. I suppose that could be done - and probably you wouldn’t need very much since the impurities are hardly detectable? Perhaps even a keyed filter with solid state ketones would do the trick. -shrug-

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If you dig deep you will find that all alkanes are contaminated with micro clusters of water, H2O n-mers…
There is a German Ph.D thesis with a 20 page introduction to the “problem”…if you are interested I can find reference (?).
Think those clusters interacting with the homoconjugates acid-ion complexes…to define your “solution chemistry idea’ for a best approximation of carboxylic acid/anions in non polar aprotic.

However, any new ideas will certainly be entertained…other than
Butane works….no theory…
There is also considerable theory of “relative “”pH”” “ based on the anions and anion pairing. …etc…

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If you look at the paper noted above…a couple of figures…
The pH of the wash uses the amine to neutralize acid…
The choice of end point pH…determines the amount of non protonated amine left over to partition into the alkane and contaminates the product.
I think this is the point…that is what is in the butane…and where it comes from…and why it continually is changing …as it is readily adjusted to the daily feed stock.

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Something to note, Primary and Secondary amines are not as thermally stable as Tertiary amines… weither that speaks more to the warm thing or reverses it to point back to the Primary amines I don’t know… I just know MDEA is no longer thermally stable after a 150c

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Fuck this noise. Scaling squish seems simpler…

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You’re suppose to write one of those …things, what are they? Haiku / poem? I was actually really looking forward to that…

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