Large Scale Extraction with Hexane/Heptane

Hexane has been used as a solvent in large scale industrial oil extractions for years. It’s highly efficient.

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Yes. There’s very large continuous extraction systems for it already available, could be converted over with little effort. Follow up with a screw centrifuge for further solvent recovery into membranes and cycling hexane back and you’re well on your way to a fully continuous start to finish operation.

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Could you send pentane through a membrane as fast as heptane?

If so wouldnt that be the better choice for solvent since it would take less energy to remove.

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I don’t have any data on that, but it might even go faster, because it’s viscosity is lower.

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Could probably just go straight to crystallization after extraction. Even if the membrane cant catch all the waxes im pretty sure solubility of cannabinoids in pentane is lower than other alkanes.

Someone om this forum said thats the reason the cold crash technique works so well in pentane when compared to hexane.

When temps drop pentane precipitates cannabinoids from the solution faster than other alkanes would at the same temp.

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Yeah. Conversely the pentane is also got a lower solvency than hep/hex for the cannabanoids. So I can definitely foresee extraction efficiency as the loss with that solvent.

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But if we’re talking about a massive system then solvent volume wont be an issue. It might make sense to just adjust the solvent volume per kg of material based on the degree of cannabinoid retention when compared to hexane or heptane at a given temperature.

The amount would probably be almost unnoticeable.

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easier to boil, harder to condense.
also more expensive.

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Pentane can be condensed without refrigeration, a big heat exchanger with a fan would be all you need provided the outside temperature isnt too high.

In the case of those big industrial oil extraction units they achieve pretty good solvent recovery rates. Also anyone whos using equipment like whats being discussed is going to be able to afford the extra cost of the pentane.

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Gotta be up North or by a river :stuck_out_tongue:

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Anyone doing a large operation can afford Pentane sure but the question is what costs more money, spending more on solvent or spending more on energy. It is a very good question but since every industry doing these extractions uses hexane and I don’t think any use pentane, i’m guessing it pencils out on the solvent side. Though the membrane transmission difference is unknown. If pentane is a lot better maybe it could be useful. It would require some detailed process analysis in the plant to nail that one down.

Another reason why hexane might be better is if your process generates any kind of heat pentane will start generating significant back pressure a lot sooner.

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Any temp rise treu friqtion in the process is a risk with pentane low bp :cry:

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As long as the system stayed sufficiently pressurized you should be fine though?

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Large scale hydrocarbon extraction can’t be done. NFPA and OSHA won’t allow that much flammable gas to be used in production. So, frankly it shouldn’t be attempted.

Only CO2 and Ethanol. Capture

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Guess thats not a independent statement😀

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What on Earth are you talking about. There are plants doing this right now for canola oil extraction, at a far larger scale than anything anyone will ever do with hemp.

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Ahahhaa right?! Sorry about your inventory bro :stuck_out_tongue:

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It could be something to do with the NFPA flammable classification of the liquid - pentane is class 1A, while hexane, heptane, and ethanol are 1B.

Most of the really big plants doing hexane extractions also to my knowledge don’t care about terpenes - they’re purely plants in -> ultra refined oil out. Pentane should have an advantage on terpene retention.

Completely wild ass guess: if you care about terps, pentane could be the better choice, if you’re just going to distillate, hexane or heptane could be a better choice. I plan on playing with both heptane and pentane to see what the actual data says.

I hope all of my competitors continue to believe this. I’ve heard this kind of statement a lot.
(Here’s a hit to anyone believes the above statement: go read NFPA 36.)

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check out the process for making canola oil.

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I only have one doubt
Pentane isn t such a good solvent for cannabinoids
IT really isn t that good at. Striping cannabinoids from biomass
Rinses Need to be long and multiple

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