FAF (fast as f***) CBD Isolate

Very interesting that it got so hot during crystallization, without any heat source.

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it was a new observance, not related to my original post. but happened nonetheless. pretty much I had the solution sitting there, stirred in frustration then minutes later crystallisation. still had the temp probe inserted and noticed the temp increase.

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I wonder if this will work with cbda? Ill have to try got a bunch in pentane though

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Do you have the rotovap spinning or still when crashing out isolate from mother liquor?

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I tried it today. It never got below 41F. I got frustrated and let it sit for lunch when i came back no crystals so i was thinking maybe its not a temperature or boiling thing ITS A PRESSURE THING. I took to it at 70 degrees took it to boil let off the valve harsh “thumped” the molecules creating a pressure shock. Did it a second time and bam isolate started falling out like crazy.

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If you roll the roto it sticks to the walls all over…

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Maybe try putting fresh hexane in the ball and heating while spinning to dissolve all the isolate then pour out into a tray to crash it again.

I’ll be trying some mother liquor/hexane in my rotovap with it not spinning and see if I have any different results.

Try my thumping method. 90% vac harsh pressurize. Release 2 or 3 times. Then pour your flask out into a jar and watch what happens.

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when pulling vac initially make sure you are getting some sort of boil or stir. The agitation creates the nucleation sites.

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Is the solvent completely removed from the solution at the point the temp starts to drop? If not, at what ratio of solvent to distillate does the temp drop happen?

no, if there wasn’t solvent then the endothermic reaction would not occur and cool the solution. Playing around with ratio’s vs time we have noticed that putting in too much solvent will cause a temperature drop so much too soon that evaporation slows to a crawl as the solutions temp drops to below it’s boiling point at that specific pressure if that makes sense. You can break this by getting deeper vac, or of course applying slight heat, sometimes even just holding the glass. Which explains @Apex situation where he did not get crystallization until adding heat. If the endothermic reaction from evaporation cools the solution too fast without increasing saturation the cbd will not crash out.

Edit: fixed a word

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Pull a vac to 95% and hold for 1 min then release. Easy peasy.

Negative 11 degrees F lol

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Yep that makes sense.

I got it to nucleate and form a few crystals, but I think I was a bit light on hexane at that point. What is your estimation of the ratio of solvent to oleoresin after initial evaporation?

I did a test run of this in the rotovap. it works great but my first go didnt have enough slurry to pour out. it ended up being a large chunk of isolate.

I did another run doing what @Apex suggested and after a vacuum releases i had nucleation points and then at that point i poured out the solvent and it crystallized in the beaker in less than 5 minutes.

I’ll continue to play around with this process. now if only i could find a way to purge the hexane from the isolate as quick as it can crystallize~

Would a series of water washes work to wash out the hexane?

I did end up getting crystalization to occur. I had to keep it above a 1:1 of solvent to distillate while cold boiling to get it right. Lightly hlding the flask helped to get it to the correct ratio.

No, you want to filter via buchner, then dry in a vac oven or atmo

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How about acetone instead of hexane? Would it need some water mixed in to make less soluble? I’ve noticed acetone does that endothermic thing when pulled through a dcvc. Are you using a magnetic stirrer under the roto ball?

Stick with alkanes for crystallization.

I just use the rotovaps motor to spin the flask, no need for a mag stirrer.

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I filtered over a buchner with cold hexane. What is atmo?