I do not believe our reactor leaks, but not 100% certain we will defiantly check for leaks when we pull vacuum next.
Are you suggesting that we could dry our reactor with just high heat with argon overpressure, opposed to vacuum?
Even my good glass vessels can be tricky to get the bottom port sealed on under vac. IMO a slight overpressure with inert gas is absolutely the best way to go if you donāt need a vacuum to work in.
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Diluting the solution is definitely an option for us, but we are working with a 25L reactor at the moment.
Do you have a suggestion or time that a drying agent is sufficient enough to dry the entire solution? is 24hours in a vessel too long?
We have not been sparging our CBD. That is something we did not think about, but will bring this up to collogues and talk about it.
We defiantly do use inert gas with overpressure while running the reaction. We do not use vacuum during the reaction at any point. We use vacuum once we clean the reactor, to help remove any moisture content that is left in the there, for at least eight hours.
When I do this, I run it for like 3-5hr at 90C. I donāt tend to start the timer until its already visually dry, and the temperature has reached 90C.
That is to say, Iāll heat my reactor to 90C with a gas sweep and when it visually appears dry - Iāll start pulling vacuum for like 5 hours with a sweep. Once Iām done with the vacuum, I release vac with dry inert gas, and then cool my reactor jacket to like 20-25C with dry inert gas flowing.
Its all a waste if you donāt cool the reactor under dry gas - the act of drying will otherwise pull in moisture from the outside environment.
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This sounds like something we should definitely try.
May I ask what temp you are running yours reaction at? We have tried various temps, started with 30C, to 50C, and then dropped to 45C and that is where we currently run at.
If you are completely cooling the system down, with inert gas to 20-25C, are you then introducing your solution from your vessel to your reactor?
I donāt actually run this reaction anymore. Maybe in like 2019 or so we messed around with it and scaled it up, but didnāt like the risks associated with it and abandoned the project
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I personally think that when sparging a blanket inert gas one should try to do this treu the solution
Either from the botom valve right under the mixing rotor or by a dip tube in solution stainlessteel sparging stones or fritted glass
And on some rogue occasions I have used aquarium airing stones Wich more often than not are made of glass with a hdpe hose pillar that have worked well in dcm Wich I call the ultimate dissolving solvent since it will chew almost anything
I believe that only teflon is resistant enough to DCM.
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What % of calcium chloride do you use?
Thank You
It all depends but in general 2 x the amount as minimum of the water that is possibly available when the solvent is/might be saturated
And then I calculate the amount of
Calciumchloride s amount of water to stay in the hydrated salt form and not dissolve becoming a brine water solution
So example DCM can hold 0.24% by volume of water at 20 C
Wich is 2.4 ml
I have another question if any of you guys have an answer for me, or can give some insight.
How were you or how are you moving your cannabinoid solution from your vessel into your reactor?
We have 10gallon keg, we melt the CBD, combine it with the heptane, Put it into the keg, then add drying solution and let it sit overnight.
After we let it dry we transfer it via positive inert pressure, through a inline sieve column, into the reactor. But were running into the CBD crashing out once its hitting the sieve column. It is made of stainless steel.
Thank You!
dilute more. simple as that. wonder why you didnāt figure this out yourself?
The CBD is not crashing out in our keg, our CBD is crystalizing from the pressure pushing it into our stainless steel sieve column. Once we remove the stainless steel column, and replaced it with a filter capsule, the CBD stopped crystalizing right away.
We assume this is due to the pressure and how cold the stainless steel fitting is, causing it to crash out o us.
Its possible to āseedā or ānucleateā a crystallization with certain surfaces. Similar idea to why people will scratch the glass walls of a crystallization dish/flask - the textured scratches on the surface of the flask can cause nucleation. CBD crystallizes pretty readily from heptane, creating some turbulent flow through a drying tube alone could easily nucleate crystallization. But also yes, across any flange/fitting etc there is a pressure drop which causes some amount of autorefrigeration and that bit of cold can cause crystallization.
If you ever run process simulation software, youāll see thereās a slight āheat dutyā associated with various valves fittings and instruments and that generally is the softwareās attempt the describe the cooling associated with the pressure drop across the valve/fitting/instrument.
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dilution will still help. this is a complete non-issue
That does make sense and that is what we assumed. Thinking about how we can add heat to the valve fittings and keep them warm so it doesnāt happen again.
Thank You.
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