How to remove wax/fat from heptane



I’ve been mulling over the idea of some LLE with heptane and methanol. I haven’t tested anything yet, but I was thinking if I washed with heptane then mixed it with cold methanol the methanol would snag cannabinoids and not as much waxes.

Now the obvious issue is the continuing build up of fats/waxes in heptane. Is there a simple in line process to remove them?

I’d assume membrane filter or -80 temps would do the trick. But curious if there’s an adsorbent or another liquid that would suck them out for cheap?



If your goal is to get all the cannabinoids and none of the waxes in methanol, why do you care if there are waxes in the heptane? Why not just evaporate the heptane later and recover in that way? As far as adsorbents, there is a thread on here where people are trying that with butane, but as far as I’m aware, haven’t demonstrated thorough removal.

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Once al heptane is removed dissolve in iso propanol and probably methanol
And pass treu aluminium oxide
All fats stay on top off the oxide
@beaker Gives a step by step
Running this sop somewhere on this forum



I’m trying to avoid having to evaporate the heptane. If I can dewax in line I can just keep cycling the same solvent. But evaporation would absolutely work



Phase change too much work?

Guess you gotta draw the line somewhere :thinking:



Lol :stuck_out_tongue: I’m already using phase change for the methanol.
Was hoping for a less energy intensive solution (no pun intended) and more continuous cycle.

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Membranes are your solution then.

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Ah, figured that might be the case.

Anyways, can I borrow $40k from you? :stuck_out_tongue_winking_eye:

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So then if the isopropyl is removed, and the oil is dissolved in ethanol at 10:1 solvent:oil ratio and frozen at -85°C for 3 days, no fats will precipitate whatsoever?

How about when the oil is further degummed after isopropyl is removed, either enzymatically or chemicallly?

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IT won t take 100 % If all fats but deffenatly about 90 %
Funny thing is winterization also Lets fats pass treu that get caught by alumina
So all in all we never catch them all
Or losse pruduct along the way dooing all these sop



Does it work with ethanol instead of isopropyl? If so, how about winterize in ethanol and filter the precipitated fats through some aluminum oxide?



Don t know give iT a shot i use alumina gritt 60/120 to have Some speed while dooing iT and do iT warm

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At least heptane requires much less energy than ethanol to vaporize/condense.

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Heptane boiling point 102C ?



Enthalpy of vaporization is much lower even though the boiling point is a little higher.
Reduced pressure deals with the temperature if needed.



with the membranes, you will have a volume of heptane that has accumulated the waxes/fats that were separated over the course of a run/shift. those waxes/fats gotta go somewhere. even using a desolventizing membrane, were left with a 1:1 solvent/product stream

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Yes, that’s true. You’ll need to evaporate some heptane at some point to get 100% recovery But you will be able to cut it down to a very small quantity.

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I was thinking a dewaxing membrane specifically, not a solvent removal one.

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What type of membrane permeability is needed? Can I separate oil from ethanol with a membrane?



Yes, evonik makes a membrane that can do that. I believe they recommend the 300 Dalton membrane.