Oh my god I love the carpet in your lab-
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I work in the shed
âŚbut I store my stuff in my spare bedroom, def not the lab itself just storage
Can you use heptane for recrystallization?
You guys kinda got me not wanting to try pentane lol
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Hexane is a neurotoxin, avoid if at all possible
Several industry leaders have reported best yields with heptane- itâs high BP, favorable toxicity profile, and better yields make it a no brainer.
If you are having issues with purge time, reserve some pentane to rinse your crystals- it purges easy- butane and propane are better still but require a CLS
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Meant heptane sorry
But is anyone crystallizing thca with heptane
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I currently crash isolate with heptane, rinse again with cold heptane, then do a final rinse with cold pentane and into the vacuum oven.
Idea is the final pentane rinse will take the heptane with it and Iâm only purging pentane from the isolate in the vac oven.
Now Iâm thinking hexane might be a simpler option if your not getting any residual solvents. How long and what temp are you purging in the vac oven to get ND with hexane?
2 days at 60c and -30mmhg, taking the trays out to remix and spread maybe every 12 hours.
As @Rowan said, hexane is much more toxic than heptane or pentane, both of which are Class 3 Pharma solvents like ethanol and acetone, while hexane is Class 2. I would avoid it if you can, but in my experience Iâve never had a hard time hitting ND (I believe the FDA limit is 250ppm?) My main concern with hexane is when unregulated labs use it and donât conduct analysis to quantify residual PPMs, if a clandestine lab doesnât do their footwork then they could be putting hexane contaminated products on the market.
My question would be, if you already have pentane on hand and use it, why not do the whole thing with pentane?
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Thank you for the information.
I already have drums of heptane around since I do my extraction with it and only smaller amounts of pentane so it made more sense to crash with heptane.
Also heating up pentane to mix in cbd distillate has me nervous and Iâd rather heat the heptane since it has a higher bp.
I feel much safer only working with the pentane when itâs cold for the final rinse.
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Pentane works great at room temp 65-75°F to melt thca. Should work just fine on distillate without having to heat it.
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Do you have a fume hood in your lab? If you dont, take a peak at biotech surplus and Ebay, you can find some great deals if youâre willing to dig.
I was used to hoods from school, but having also come from black market extraction I can say adding hoods to work with solvents and adsorbents is a game changer. I definitely hear you on warming pentane and concern, if youâre working with 4L or less with adequate ventilation and training then you can manage your concerns fairly well.
It all comes down to one of the laboratory golden rules: Know and anticipate all dangers, design for safety, utilize for excellence.
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No fume hood yet but itâs definitely on the to-do list. Iâll have to check out eBay for one.
New to pentane and love learning about all the different solvents.
How long would 5 gallons last? This sounds like a dumb way to ask. Ha. It seems like a small amount.
Depends on what youâre using it for.
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Very true. As the primary solvent? Or for recrystallization?
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As a primary solvent, it all depends on how youâre recovering and how youâre using it.
If youâre using it in a closed loop system, youre looking at minimal loss.
If youâre using it for recrystallization, you lose more. How much more? I canât sayâŚ
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