Exactly, @Zoraku! THCa (pKa 3.5, I believe) + base = THCsalt + water.
THCa crystallization lattice is dual hydroxyl mediated:
OH-THC-OCOH * OH-THC-OCOH
HOCO-THC-HO * HOCO-THC-HO
Changing that carboxylic OH to sodium, potassium, or some other conjugate acid moiety screws up the molecule’s ability to form a lattice… unless it retains enough positive charge after neutralizing the THCa.
Yes that is what I was thinking, it’s been awhile since I’ve done any significant crystallisation work, at least THCa is much less finicky than the crystallisation of protein-substrate complexes.
If the pKa is indeed that low then even a slight shift towards a more alkaline environment would have a great effect on the rate/ability of crystallization. I would assume the pKa would be closer to 5 but haven’t been able to find and literature. I think you could probably get a good estimate by taking the same extract and trying to crystalize at pH 3, 4, etc up to 8 and see where the big drop is. That would most likely be where you have complete deprotonation.
Yep! It’s still very weak, being a positive value pKa, but yes, pretty much any dissociated base (nucleophile) present would deprotonate it.
How does carbon powder (charcoal powder) differ from what’s inside a Millipore filter? In terms of the surface chemistry between the THCa and the filter media. Is there a big difference between the media?
That would depend on the source of “charcoal”, and the flavor of millipore filter you’re comparing it to.
Having spec’ed neither, it’s pretty much impossible to answer that question.
Is the carbon “activated”?
How?
acid? Which one?!?
How fine is the powder?
Is that a tight range? Or just the average partial size?
Are their binders in the filter cartridge? are those binders compatible with your solvent of choice?!?
Hey photon,
A quick question on the existence of the pH only in the aqueous phase—preamble here about the context in which I ask the question:
If one were to run a cls with butane/propane, it seems like the combination of pressure/hydrophobicity would push the water (contained in the biomass) towards the bottom of the “material column”, it seems that this would be especially true if then extraction was cold, given the relative density/viscosity of the two phases.
If the pH is concentrated in these pockets of water, wouldn’t it seem as if these pockets could act like the stages (or trays) of a counter-current liquid-liquid extraction vessel?
In other words, couldn’t the activity of an acidic (or basic solution) be encountered in these aqueous pockets and, in turn, affect the quality of the extracted product?
Ph exists even without water
You just can’t test for it without water
This is pretty much the whole point I’m trying to make
You don’t need water for and acid or base to work
If you throw baked t41 into your crude it’ll make it acidic
You wont be able to test the PH till you dissolve in some 190 proof ethanol which has enough water in it to check PH
Maybe lightly off topic…
But couldn’t some of the increase in nucleation rates actually be caused by the tiniest of b80/celite/etf. particles making its way through into the extract, and creating increased surface area for nucleation?
just wanna say thanks for giving us all a crash course / reminder on acid base chemistry without judgement. Very useful stuff in this thread presented in a clear way. Can’t get much better than that.
The range you are experiencing could also be due to the fact that water can dissolve into what was at one point neat ethanol. Without the use of desiccants such as molecular sieve beads, any pure ethanol will take on water at some point in time.
Do you dry your ethanol with a desiccant? Without dry solvent you can definitely bring water moisture into your extract which could cause stability issues
I do not use desiccants to dry the ethanol. Is it possible that older carbon powder (summit carbon A) could be pulling significant moisture onto the carbon surfaces and effecting issues later with THCa:THC ratio?
@TheGratefulPhil, it looks as if you are envisioning and thinking about an emulsion of sorts. Good questions! In a genuine emulsion, yes, any pH would exist only within the bubbles of water. So if there is enough water dissolved in the hydrocarbon, such that it precipitates as microbubbles when some parameter changes, like temperature, any acid or base present could cause those water bubbles to have pH values different than 7. Water ALWAYS has a pH value.
The pressure doesn’t do much of anything, as long as the phase of matter is liquid, but generally water has a higher density than those hydrocarbons, so it would coalesce at the bottom of a still volume.
Would it affect the extraction? Of course! Water will always affect the extraction, especially when dissolved in the hydrocarbon. If that water was or is pH adjusted, that will also affect the way it extracts things. So, yes, pH can affect an extraction performed with hydrocarbon and dissolved water. Dissolved (not-yet-dissociated) acids and bases in a hydrocarbon will (little as there may be) can also affect extraction by ionizing in contact with water (they will attract it, in fact) or other compounds on the biomass.
Still, @Kingofthekush420, again, pH is the specific inverse logarithmic function of hydronium (H3O+) ions in water and ONLY water. These are present all the time in all water, unless it is electrolyzed into hydrogen and oxygen (i.e. NOT water). What you are talking about might be:
A. dissociation of ions (which only happens in polar solvents, like water) or
B. redox reactions (which can happen almost anywhere).
Either way, if it is not in water, there is no pH! Lol! 
Thc can be deprotenated or protenated. Many substances can be which is my point.
If you take some thc and run it across a magsil column it will deprotenate the thc even though theres no water present
When you dissolve your thc in 190 proof alcohol the thc will then deprotenate the water, altering ph
If this weren’t true why do we need to water wash after magsil chromatography to get a proper PH? We use distilled water as our reference to return the wax to the correct PH. Water has nothing to do with this
If disassociation only happened in a polar solvent magsil wouldnt cause funny colored wax.
Also, does that mean that MgO only works in ethanol to reduce decarb temp?
I dont think so
I don’t think so on that last part, either!
I hear what you are saying about protonation and deprotonation, and you’re not wrong about that part. That is due to differences in solid phase (considering single molecules to be “solid”) nucleophiles/electrophiles. It is oxidation/reduction. It is reaction. It is not inverse natural log of hydronium ion concentration (pH).
Ethanol is what I call a “semi-polar” or “partially polar” solvent. It is actually polar enough to be mildly acidic in water; it donates protons to water molecules, making H3O+ cations. Ethanol in ethanol, this does not occur, because every molecule is the same… since they all have the same nucleophilicity, nobody donates anything. Weak acid does not dissociate much at all in pure ethanol, but it might a little bit, depending on the competing pKa/pKb relationships of the conjugates. Strong acids can dissociate more… Regardless of the fact that these are still just H+ protic cations and zero OH- anions, one could say there is a theoretical pH present. And you are also correct that it cannot be measured.
Using 190 proof ethanol is just using water. It has pH. Whether there is acid, base, salt, cannabinoids, radioactive isotopes, everything or nothing at all in it, but water, it has pH.
I am not arguing whether or not dissolved acids and bases have an effect on washes or other extractive processes. We know they do. It’s just that pH is not the only effect of acids and bases!
Bingo, my 2 cents, anything and everything we pull into solution could effect pH quantification. Various compounds and environmental variables play into it. It’s a lot of heavy duty “sciencing” happening, the condition of material, moisture content, environmental factors of the material, media used to scrub your material, solvents, affinities/fluctuations, added material, general processing, insert variable here, there, elsewhere.
I am garnering more and more of an appreciation and respect to the people moving this science forward, I hope to be well rounded enough to grasp it as well as displayed here, to have a real 2 cents, as I am curious what the implications of the discoveries made will bring.
Thank you for giving me homework and more rabbit holes to chase down. You gents are a lot to keep up with.
Do you notice a color difference between the t5 and t41 ?
Has anyone tried using magsil or aluminum oxide to create a stable, crystal resistant CBD distillate?
using magsil or AO how? if you mean to just change the PH level to create a crystal resistant than yeah, people have tried, not sure its the right solution since changing the ph of a finished product will drastically effect the shelf stability.
I am trying to create crystal resistant by taking mother liquor and then using chromatography to remove THC down to below 0.3. After distillation though my levels are up to ~70%CBD. I added 10% CBG by weight but it still started crashing out after about 2-3 weeks. Was wondering, if I changed the pH if that would help but not sure what it would do to my color as Im trying to get a nice golden color for a vape cart contract. Shelf life would be another concern as your mentioned.
Any help would be appreciated.
Thanks,