Simple LLE SOP wanted for prep for WFE

I’m stuck running crude from a guy who is “cryo” ethanol extracting at -40. Predictably, I’m getting a nice caramel crunch on the inside wall of my wiper on terp strip pass, and chunks of busted toffee in the disty. We don’t have this problem with our stuff, extracted at -80, and since the gunk is water soluble, I’m assuming I have a sugar problem.
I’ve done the searching and seen references to SOPs for remediating this, but haven’t seen any complete SOP available. Is there a simple process out there that one of you uses that will get me back to a clean wiper and maybe allow some of the hair to grow back on the top of my head?

Thanks

Dissolve crude 1:1 in heptane. Add water, stir/agitate. Drain aqueous layer. Repeat until water is clear. Rotovap and distil. Can also try degumming with 5% citric acid in first wash. Generally best to winterize afterwards however

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Thanks McFly. I’ve seen a lot of discussion of the use of brine - have you found that this is not necessary? I’m assuming the water is at least RO or distilled?

Greatly appreciate the help.

you could throw in some saline and sodium bicarb washes as well… distilled water is sometimes tough when youre doing washes at large scales. in smaller scales its fine to get from the grocery store… ive switched to RO water but noticed my emulsion layers can be a bit more stubborn

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I’ve got access to Pentane, which I know is similar to Heptane. Would this work at an equivalent level? I assume we’re just trying to get the oil into a non-polar solvent and then adsorb the sugars into the water? (Not a chemist. At all).

Heptane is a little better for reactor work , but pentane will do. The only issue is, pulling too deep of a vac on pentane will evaporate a lot and lower the solubility. Pentane would work great in a stainless steel reactor, so that you can work under pressure and not vac.

That being said, if you have access to heptane I have an epic sop I can walk you through.

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Depends how dirty your material is. Pentane won’t work if too dirty the emulsion will take days to break. Salts might help but if real dirty heat is way better to break emulsions. As for water just make sure your ph out = ph in otherwise you’re gonna make d8

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So I’ve been dealing with this alot lately and I’ve found I only need 1 water wash to clear all the sugars out

The only reason I do 1 is because the second doesn’t seperate fully no matter what and it becomes a bitch to remove the water from the crude after

Just my .02 cents!

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Thanks much @Kingofthekush420 , that’s what I wanna hear. I only need to clean it up enough not to gunk up the wiper and wreck my gear pumps.

You’re doing this with heptane and water?

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I’ve got heptane ordered, but it takes a bit to get it here (rural mountains of BC)

I’ll most happily take you up on your generous offer of an SOP when it arrives.

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Heptane, water, and 50 grams of salt per liter of water used

The first one on really bad warm ethanol crude will come out red but you’ll get most the stuff you want out.

The second wash will seperate about 70% of the way and the 3rd about 50% (if you’re doing a 1:1 water to crude&heptane mixture) this is why I only do 1 wash

I get canning salt from Walmart, regular salt has a caking agent in it. You also want the pH of your water at 7.1

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Another way to remove sugars without solvent is settling them out. This works best with a solid bowl centrifuge. It can be done with gravity in a heated container over time.

-Heat your oil to 140C after decarb and allow to cool to room temp.
-Cycle your temperature between room temp and 80C over several days.
-Decant the oil at 60C. Most of the sugars should have settled to the bottom of the container.

A solid bowl centrifuge can remove any of the sugar that crashed from your solution in a few minutes. The gravity method can do a decent job, but you’ll still have some sugar to deal with in the wiper.

For LLE, I’ve had good luck making a water/oil emulsion and hitting it with steam to dissolve sugar into the water. Then breaking the emulsion with a L/L Centrifuge. Haven’t had the opportunity to scale it up yet, but it’s promising that the LLE can be done without adding a solvent other than water.

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Hey, I wanted to follow up with a “thank you” for the help, this worked beautifully.

I tried a sample of our own crude using the same process, and the photo below shows the material removed from the other extractor’s crude vs ours. These two are from identical-volume samples. A world of difference.

Process: We agitated for 10 minutes a 1 to 1 ration of heptane to crude, and then introduced a similar volume (1) of 7.1 ph water with 50 mg/l canning salt. Agitated another 10 minutes, decanted into a reactor with a sight-glass on the bottom drain, and waited another 10 minutes. The aqueous layer separated almost immediately, such that we could already drain it off after only a 10 minute wait.

The only difficulty was removing ALL of the heptane. We rotovapped the hell out of it, and still got some odd lights in the terp trap on distillation that I assume was the residual heptane. That made maintaining vacuum a little trickier, but I gather that we can just boil off the final 5% before distilling, or live with slightly wonky vacuum and heptaney terps.

As always, the community at F4200 (and @Kingofthekush420 in particular) generously shared their expertise, which is part of what makes this site so great. Muchas gracias guys.

John

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We played with this same SOP, and found that heating up the wash and increasing the salt fraction helped split stubborn emulsions.

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Not sure what scale your at and whats practical for washing it all. We run -40 also and still deal with it but decarb in a jacketed vessel at 140, when done let it cool to 110 and filter your drain output using these. I find the walls of the decarb vessel will eat alot of it. Clean with hot water afterwards. Have never had issues with discharge from the wiper. I also clip a screen over my distillate discharge port as well.

https://www.amazon.com/gp/product/B07V7YF29Y/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1

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Right, we have been heating it during agitation as well. In fact there’s no way to get the crude in solution with the heptane without some heat.