ReXing THCa in pentane

Background:
Extraction is usually done in isobutane using a 2 stage CRC protocol.The 1st stage going into the collection vessel 2nd stage when a product is moved from the collection vessel to honey pots. In this Instance stage 1 media was reaching saturation so this fraction was dumped into a small pot (6x6 with a base). After recovery a dark goo was put aside to be dealt with later. Upon opening large crystals were observed and felt when a tool was moved through the product. So I filtered out the THCa via desktop Fuge
I would like to reX in pentane. My questions are:

  1. cold pentane?
  2. how cold?
  3. jar tek cold crash?
    Or room temperature?
  4. Jars in vac oven at 95F?
  5. Ratio of material to solvent?

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two steps

redissolve in HOT pentane (pressure vessel helps)
cool down (slower makes bigger crystals)

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Hot= 72f, 95f…or

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Thank you for the input but the me take your suggestion and try to clarify I heat my pentane on a hotplate to 95ďľź i add the product while stirring I let this cool to Room temperature then move it to the refrigerator for a few hours to take it to 40ďľźF then I moved to my freezer which will take it to negative 29C?
Is this a correct clarification of your advice?

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Theres so many threads with every answer you have on this subject

Also please don’t use pentane on a regular hotplate

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crystallization in general:
supersaturated solution. a saturated solution involves adding solute to solvent until no more can be dissolved. supersaturated solutions involve heating the solution in order to be able to dissolve more solute than you normally would be able to. when this is done, as the solution cools, it loses its ability to hold that extra amount of solute, which then crashes out of solution in its crystalline structure.

so when youre trying to recrystallize, you want to bring your solvent up to near its boiling point, and add as much solute as you possibly can. you want it to be as concentrated as possible while all still going into solution this is key. this will likely involve some calculations before hand.

then cool your solution. solubility decreases with temperature, so as it cools your thc will drop out of solution as a crystalline solid.

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Thank you for the input I will be doing this shortly and will update with photos and details

Pentane boils at ~body temp (36C/98F).

Would you heat an open container of butane to -3C? On a hot plate?!?

That is not quite what you’ve proposed here, but damn close.

I recommend your CLS…

And some reading. Although the basics are all here.

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Thank you, however I was being a little bit facetious based on the advice to use "HOT PENTANE " Without defining how hot hot is…around here hot is about 80゚ since everything else is done it’s cold possible.

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I will build a small vessel with PRVs from stainless steel parts around here And add heat via hot water bath.
Don’t get me wrong I appreciate everybody that contributes to this forum and it is in amazing forum every nascent industry should be so lucky. But as a scientific forum I don’t think people should say add a smidgen of this to a bunch of that get it hot…
Science and our safety deserves precise language whenever possible.

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Just a random though…sometimes supersaturation requires cooling not heating such as sodium hydroxide in water

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hot equals 31c (87.8f) within bp of pentane

If heat is relative, then check the boiling point to see what “hot” means

Your attitude is gonna leave you with 3rd degree burns. Slow down, think, breathe…

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Advice taken. Stress level currently 11

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The fact that pentane has a very high vapor pressure makes it much more likely to be ignited. Even far below its boiling point pentane is still a pretty decent fire hazard.

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And since we’re assaulting the horse corpse here, static dissipation with alkanes is poor so the likelihood of a static arc when that pentane evaporates off the hotplate at 15 degrees below its boiling point is fairly high

Edit: well hopefully the OP hasn’t lit anything in fire in the last month :person_facepalming:

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Did the person who flagged my post think it was an insult…? :woozy_face:

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Lol wtf. Someone’s just out to get you bud. I laughed my ass off

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Please don’t!!! …

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