Dilute resin with MCT oil BEFORE Rotovap

Hello everyone,

Does anyone have any experience in running a rotovap to distill ethanol once winterized cannabis oil (from CO2 extraction) has already been blended with MCT oil?

Traditionally the winterized cannabis/ ethanol solution is distilled using a rotovap, then oil is added to the cleaned resin to create an oil blend.

But removal of the resin from the Florence flask can prove difficult. So if we could blend it with MCT oil first it’d help.

Any feedback would be appreciated

If it has ethanol in it AND it has MCT oil in it, reduce temperature below the freezing point of the MCT and filter it.

Rotovap and then readd MCT.

i think they want to add MCT to their ethanol tincture… as in add it before they recover their etoh so the viscosity is low after recovery and enables them to “pour” it better i guess?

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Sounds like a recipe for burnt coconut oil :mask:

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ya not sure that would go over too good but i dont know the chemistry behind adding mct straight to the tincture.

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I know that @cyclopath has a fondness for the addition of MCT to reduce transfer loss. He has encouraged me to use it before in similar situations, though I never had the opportunity. Maybe he’ll chime in too…

Sounds fine, try it.

You got it. I’m not sure this has ever been attempted, or what effect it may have on separating the EtOH from the oil.

Depends on your heat source. If you’re using a rotovap with water as your heat transfer fluid, you’re not going to burn anything.

An uncontrolled heating element? Sure…but you’re just as likely to burn your product in that setup with or without adding MCT

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The Rotovap uses a waterbath to transfer heat to the sample in the Florence Flask.

My concern isn’t with burning the product, but with how MCT oil may effect ethanol separation from the oil

The ethanol should evaporate just fine, and you shouldn’t have to worry about burning anything. The only concern I would have is separating the oil from the resin, but you aren’t doing that. Let us know how it goes.

It has.
It helps. Especially if you don’t have fancy tools like rotovaps.

And makes things move easier when the ethanol is gone.

This was helpful, thank you.

I’ll pass on the info to the higher ups and see if they want to try it out

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If you’re still skeptical, get a tare weight of your roto flask. Then once ethanol is fully purged, add your specific amount of mct relative to the weight of oil on the flask. Spin the flask on the rotovap with some heat to get the solution to mix

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I came across this old thread quite by chance. I currently extract on a small scale (run size around 1Kg of biomass) and am working on product development. I had been frustrated by the difficulty of fully purging ETOH from resin, given that as the level of ETOH reduces then the viscosity of the resin increases, hindering the release of further ETOH. I have recently switched to using a vacuum chamber for this process. I hit on the idea of adding MCT prior to final purge, initially on a 2:1 ratio to anticipated CBD yield. It appears to work very well. Purging time is reduced, and subsequent testing using a magnetic stirrer hotplate showed no signs of any ETOH bubbles, even when taken up to 105degC. As my CBD is being mixed into tinctures and salves, using bases of MCT and coconut oil respectively, a simple calculation is all that is needed in order to compensate for the initial injection of MCT.

As to previous comments concerning the possibility of burnt coconut oil, refined coconut oil (Crisco for example) is extensively used for frying food, at much higher temperatures than those used to evaporate ETOH, especially under semi-vacuum conditions.

yep. works great. so long as you actually want your cannabinoids in MCT.

some concept applies is you’re adding ethanol to winterize BHO. No need to vacuum purge the first solvent before adding the second.

see: No need to purge crude that’s going to be winterized?

indeed. “burning” coconut oil at 78C is probably gonna take some prep work.

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