CBD isolate not crashing in pentane?

I’m trying my first small scale pentane isolation and having some difficulties.

I started with 125ml of first pass cbd distillate warmed and added to stainless steel mixing bowl, then added 500ml room temp pentane and mixed while in a water bath of 45c until the pentane started to boil.

I then let it cool down and put into a deep freezer that gets down to -33c. It’s been 24 hours so far and when I just checked on it it looks like the distillate has separated out and is at the bottom of the bowl.

Im wondering if maybe I didn’t mix it well enough while warm or if there’s a possibility my distillate doesn’t have the needed cbd % to allow crashing. I haven’t had this distillate lab tested so it’s hard to say percentage.

Here’s a video of what it looks like when stirring.

The mixing isn’t the issue. Have you put a seed crystal in? While high CBD distillate will spontaneously crystallize, distillate with marginal percentage CBD will need a kick in the pants to start. And if it’s too low, it won’t work at all.

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Unfortunately I don’t have any CBD Isolate to seed it with, guess I’ll need to order some.

How much do I need to seed it with?

Just a little dusting. More importantly though, you should know what the potency of the distillate is going in. That is the only way to know what yield to expect. I actually have an equation showing expected yields for different ratios with this method.

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besides the seed material you need to ramp down the temperatures. after boiling let it cool to ambient, then put into a regular fridge, regular freezer, and finally the deep freeze.

its all about the temp ramp.

Also, i have a sneaking suspicion that when you have a extreme jump in temp changes, ie ambient to -33c you decrease the total amount of available “energy” so much that there isnt enough energy in the system to start and continue with crystallization, so everything just drops where it stands. ive observed this numerous times. just my thoughts on this.

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I see, looks like I need to have this distillate lab tested to know what I’m actually working with.

Anyone know somewhere cheap/fast to get testing done in Southern Oregon?

i always use green leaf in portland, they are good people

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I had a feeling it was the extreme temp jump from boiling to room temp and then -33c.

I’ll reheat and try a slower transition from room temp, fridge, regular freezer, and then deep freezer like you recommended and see what happens.

Will be ordering some isolate to seed it with too.

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give it a shot, report back your results!!! best of luck!

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Definitely seed and slow temp ramp I’m all in on that one. Curious as hell please report back I’ll follow this thread🤙

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is that something you’d be willing to share?

I had I client tell me yesterday they expected 37% losses in the crystallization process, I laughed at the precision, and asked where they got that number from.

not saying it’s wrong, just that 30-40% would seem like a better characterization, and even then, that is making assumptions about the input cannabinoid ratio.

if the biomass in the field is 1:1 they won’t be crystallizing anything…

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Try saturating the solution more. You want to get to the point where you cant dissolve any more distillate into the pentane.

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Scratch the glass with a lab tool

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Yes, you need to know the ratio and potency first. If you do you can make a prediction very close to quantitative. I mean there’s always an error margin but I was surprised how well my predictor worked, and it was derived from many data points. If anyone is interested in it please DM me for now. I may eventually post it down the road.

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We had the same issue, ended up being too rapid of a temp change causing the oil to fall out.

After heating let sit to room temperature, then put in the freezer until 0c, then seed, then incubate.

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Thanks for the help, I was unsure about what point to seed at.

Got a gram of isolate on the way so I’ll be able to seed it.

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When you crystallize you dont want to move the solution around, it will cause some of the small crystals that have already formed to dissolve back into the solution and slow down your process.

Ideally you would want to use a chiller with a wide temperature range to cool the solution inside a jacketed spool instead of setting it in the freezer, because it would allow you to ramp down the temperature without having to move the solution from fridge to freezer etc.

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old school crystallization trick ;D

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Thats not necessarily true, yes there may be microfluctations in saturation of regions of the solution but any dissolution of product will be net-zero by the end of the process(with proper temp control). Since it really only takes a couple hours to crash all of the cbd out, the point is moot.

Youre using too much pentane and need to agitate way more. You dont need a seed if you have proper saturation rate and adequate cold agitation

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What ratio of pentane to distillate would you recommend?

Also at what point in the temp ramping down should I be agitating while cold?

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