Preserving Terps from EtOH extraction

So I recently got some super cold ethanol extract from some beautiful trimmed finished flowers. The ethanol crude smells amazing. Wondering if there is a way to capture those terps and not destroy them?

Maybe boil off the residual ethanol at 60C under full vac, then try a steam distillation on the remaining product?

Azeotropes are hard to break, majority of the short chain terpenes are gonna go with the ethanol. Taking the ethanol off will still leave a large portion of them, but, it won’t quite be the same.

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I believe the trick is to alter the solvents affinities.

possible routes are salts, water, LiqCO2…

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Should come out w the etho right?

I’d probably stir and use some inert gas and some strong vacuum. Only add just enough heat to keep it liquid enough to stir. You could possibly find a good azeotrpe with pentane as well.

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What do you mean by adding inert gas?
More why are u using it?

https://www.google.com/search?q=inert+gas

N2, Argon, Helium…

heat + oxygen = chemical reactions you don’t want.
aka oxidation.

https://www.google.com/search?q=oxidation

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Thank you. Would protic and aprotic be same thing?

exact opposites.

haz available proton (H+). vs has not. ish

image

In general terms, any solvent that contains a labile H+ is called a protic solvent. The molecules of such solvents readily donate protons (H+) to reagents. Conversely, aprotic solvents cannot donate hydrogen.

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Sorry I’m not knowledgeable in chemistry at all so might word things weird.

I was just reading about protic and aprotic last night after reading the ethanol diamond thread. So I was wondering if that’s what could be same here (ethanol protic, inert gas aprotic) and by that train of thought if aceton could help.

I see now that was flawed. Thanx for taking the time.

no worries. the inert gas is just there to stop things reacting.

boiling the ethanol off at atmosphere would boil off many of the terpenes. using a fractional distillation setup to separate by boiling point is an option, except that high heat and O2 will wreck many of the delicate compounds we’re after.

performing the distillation under vacuum, and backfilling with an inert gas to lower those temps, and remove O2 from the equation might make it possible to remove the ethanol selectively (add back anything that boils off before the etoh).

the other option is to turn a great solvent in to one that is less great. by adding stuff.

adding liqCO2 is probably the most tunable solution, and if direct distillation from biomass isn’t a better route, I imagine CXE (CO2 expanded ethanol) will eventually be our go to. @Plant2pipe?

Adding water makes you a loucher :wink:

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Has anyone tried what you are describing with using CO2 to selective pull the terpenes from the ethanol solution? Or any of the other ideas using inert gases?