Evaporating 100% Heptane from distallate

CannaBusiness
1

Tried a search for this guys but Im having trouble removing 100% of the heptane via our roto. Killer vacuum with temps at 75c. It pulls 95% of it but i know their is residual heptane as I can smell it. I understand that a second pass would remove all of it, but i am trying to avoid a second pass. How hot do i need to push this roto? I dont like the idea of going to 100 or something.

Any tips or pointers much appreciated. I am running the roto until i see ZERO drops condensing anymore yet still smell it.

-Joshua

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Temperature is not high enough.

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heptane is a bit persistent in these viscous oils. If you think its worth your time, take the round bottom and put it under high vacuum (rotary pump) with heat and stirring (mantle/sand bath on a stir plate should work). Even then, I would not expect you to remove all heptane, just considerably more heptane that is feasible via rotovap.

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Distill it again.

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Redissolve in ethanol to dilute the remaining heptane, even though heptane boils at a higher temperature than ethanol the addition of ethanol will greatly lower the surface tension of the liquid and allow the small amount of heptane to boil off along with the ethanol.

Only reason i advise doing that is because heptane, pentane, and hexane all smell like gasoline and its very easy to detect by nose in small quantities unlike ethanol.

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Would this be effective at removing all trace elements? As if i were to have it tested for residual solvents in a testing facility would i be clear? Im trying to make the product sellable.

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I am aware it will remove the rest. I am trying to sell pesticide remediated 1st pass.

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The maximum allowable residuals from a given solvent is different for each state but as far as i know ethanol usually has the higher number.

I would imagine you’re not going to remove ALL the heptane, but you should be able to remove it to below odor threshold levels.

Just make sure you allow the alcohol to violently boil if only for a minute or two to make sure your boiling the heptane.

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Ive read that Neopentane has no odor while i know from working with N-Pentane that it smells like gasoline. Costs an arm and a leg though lol.

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you’re going to need a thinner film and/or a deeper vacuum. long chains are hard to get out.

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@ScoobyDoobie is right to remove heptane below sense treshold
Boiling ethanol along in the last part works
Yet i must say i have had to do iT up to 3x on occasion to get rid of the smell
Although i also think that the smell treshhold is way lower than your solvent state treshold :+1:

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the reason this might work for removing heptane is that ethanol and heptane have an azeotrope - if both are present then will both co-distill at a fixed ratio and if there is considerably more of one then the other, than the lesser will eventually deplete. So dissolving in ethanol and concentrating multiple times should remove the heptane. This is called azeotropic drying.

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it should be super easy to remove all the heptane in your extraction. what sort of vacuum are you pulling?

You said you using a roto so it should be even easier. Maybe gasify the undistilled material and then pull a vacuum

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Well dr josh heptane has a oder treshhold higher than hexane but is still tough to get rid off onless You have a hands on experience sop for us😀