The A-C sop to D8 does not use a solvent at 5% by mass
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P-tsa does use a solvent Depending on end product
Hcl gas i use as solvent iso propyle
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D8 reflux AC at 5% at 180c for 4hrs per liter of cbd distillate added?
To get d9 you use anhydrous hcl gas bubbled into the mixture and isopropyl as solvent? All under inert atmosphere, and dry conditions? In a SS pressure vessel.
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No hcl gas makes D8
For D9 it s a Total diffrent sop
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Okay, thanks. Is your method available to convert to d9? And is it a d8 to d9 conversion?
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Another simple minded way to visualize the reaction/pressure/temperature variables:
For refluxing to occur, the liquid phase must be above its boiling point. The refluxing simply returns the vapor phase molecules to the liquid pool, after they have boiled off.
As has been noted, when a liquid is heated, molecular activity increases, as do molecule collisions. Boiling point is reached when those molecules colliding with the liquids surface have enough velocity and mass to exceed the liquids surface tension, and the atmospheric pressure upon the liquid surface.
Increasing atmospheric pressure doesnât slow down the molecules or rate of collisions, it simply stops them from escaping into vapor state, by increasing the Heat of Vaporization required. The boil at the increased pressure, requires higher molecular energy to break through the surface, so the boiling point is raised.
If temperature is held constant and the atmospheric pressure raised so that boiling ceases, the molecules are still darting about at the same energy level, just not breaking free into vapor state. That essentially performs the same function as refluxing, which simply returns the vapor to liquid.
It does so without removing energy from the vapor molecules to condense them back to a liquid, so both more molecules and more energy remains in the liquid state reaction.
That begs the question of why reflux if you can do the same thing with pressure???
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This is lighting up a couple things for me- would you say that if you were using a vessel with a lot of headspace because the rxn mixture didnât fill it over say 30% volume, that it would be considerably slower than a vessel that was filled to 60% volume with rxn mixture?
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Getting a replie from you is an honor 
Some time has passed since I started doing the refluxes under pressure
And I still recomend the use of a cls as reactor for synthesis
Even thou there are pros and cons
As it s use is very easy and can Handel a lot more than glass
Main cons the stainlessteel is not very fond of certain acids we use in isomerizations
Another con I struggled with was stirring speed
The magnetic heating plate works but if you really want to stir an overhead mixer is needed
And the magnetic coupler to be able to work with pressure is expensive
Some reactions create a gas Wich one wants to get out off the reaction atmosphere ASAP
Like with hydrogenation reactions where H2 wants to escape and canât at least not out of the rig
I solved this by having a pressure relief valve
Use one with a flanged outlet
set at the pressure I want to run the reaction at and then backfilling with argon and the argon manifold set at a few psi higher than the prv
This way I can refresh the atmosphere above the reaction (head space) still have the overpressure in the vessel
But the main advantage is beeing able to raise
Bp of solvent used and hence speeding the reaction or it s cleaning up Afterward
Example using pentane at the bp of heptane
And there for purging of the alkane way faster
All in all I think the basis for this idea was yours and I thank you for that never would have known a cls if it wasnât for you 
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If you are asking about whether or not the volume of the headspace affects the actual pressure, the answer is no⌠but possibly yes, for the opposite reason. The volume/height of the reaction mixture will increase the pressure on the liquid below the surface. Where the headspace gas pressure affects the surface liquid, the upper liquid volume will also affect the pressure on all the liquid beneath it. The difference is gas pressure or liquid pressure.
However, if youâre interested only in the gas-phase interactions, then it is probably the smaller headspace that would have the greater rate of reaction⌠this is due to the greater vapor concentration nearest the liquid surface versus further away.
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That answered my question, thank you
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How much PTSA is in there for D9? It will depress the boiling point proportionally to its concentration.
Pressure vessels are expensive and dangerous to operate, limiting their usefulness somewhat.
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I never use ptsa for D9
I dislike ptsa in general for any reaction but thatâs me
What are you using for D9?
Phosforic , hcl ,and a carbonic acid
All make D9
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Thanks for the honorary brother! It is good to see you experimenting and pushing the state of the art!
Good point on the suitability of 300 Series Chromium based stainless for use in organic acids. We stored 70% Nitric in 316L SS tanks, but take a look at the following link to note its performance in other acids like Acetic, hydrochloric, hydrofluoric, sulfuric, and citric.
Yeah, a magnetic stirrer doesnât work well with that much iron in the way, which gave me a brain fart. At the relative low pressures the reactor is operating under, you could put a window of something else like borosilicate/ceramic in the bottom where the stir bar sits.
As overhead mixer is certainly the most reliable in viscous materials and what we used in our chemical processing processes. Typically a pneumatic Lightening mixer that is explosion proof and operates in noxious atmospheres with relative impunity.
Good idea on the argon blanket with bleed! That should certainly encourage any hydrogen generated to seek higher ground. We used similar techniques in inert atmosphere weld chambers, where the argon atmosphere floated out any lighter gasses such as nitrogen, oxygen, and CO2.
Iâm thinking that raising the bp was probably the single greatest driver in reaction speed.
Glad youâre having fun!
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Ummm, reflux condensers and ancillaries arenât cheap either, and the pressures involved are relatively low. The biggest advantage of pressurizing that I see, is to raise the boiling point so that the solvent can be heated to higher temperatures. At any given pressure, a solvent canât be heated hotter than its boiling point.
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Ok I am starting to believe that isomerization reactions work better in darkness than light
And that this might be the reason my yields are better in the cls than in glass
Did some trails and it really seems like light (UV) affects the yield. Or creates side reactions
So whatâs your thought. On the matter ?
@Photon_noir
@Ennui
@ScoobyDoobie
@silverstudent
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I havenât experimented with light deprivation during my reactions. That said, it seems to me that you may be on to something there. UV light can certainly catalyze reactions, I would imagine that it could also effect product formation.
Iâm betting @photon_noir will have more info
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I did 3 trails in 100 ml flask at the same time spinbar speed was identical
Dryied acid from the same flask
Dryied cbd from the same flask
1 setup in a normal windowed room
One setup in lsd lab lightning
The darkroom results are cleaner conversion and higher yielding of target cannabinoid
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How thoroughly are you baking out/drying your labware? Could be a difference in how much water is sticking around on the interior surfaces too