Cleaning Crude

I need help, not looking to be spoon feed, just need some sound advice. I have done a lot of reading with regards to cleaning RSO.
I have Methanol, Hexane, AC, DE, Bentonite clay and a 2lt Sep Funnel, I need to cleanup 200g of 75% THC RSO crude.

is crude usually that potent?

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Seems like you have what you need to simply dissolve the resin and pass it through a bed of adsorbent media. At that point, you’re looking for dilution ratios and a starting media to resin dosage.

There would also be the question of your goal in cleaning this resin up.

My go-to would be 3:2 - 2:1 Pentane/Resin, and the dosage is tricky but I think 2:1 Media/Resin Grams should do it with well-activated bentonite clay. :+1:

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I dont know this stuff so im asking for other people who dont know like me. Isnt rso supposed to be not over processed and that the whole concept of it? And are you gonna eat it? why filter it if so? And im still surprised a dirty product liek that has 75 percent thc? mustve been some dank bud.


You filter it so you have even cleaner crude going to distillate.

Less garbage, better distillate


ive nevver done etoh extract or distillate. I thought 80 ish was good for hydrocarbon extract? by good i mean acceptable. I base my guess of edible potency off that. I kinda leave some garbage in- its full spectrum that way and seems super potent.

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Yes when you playing around with premium bud.

I only have methanol and hexane to do the job, couldn’t find heptane or pentane here in SA.
Thanks for the advice. :call_me_hand:t2:

I have crude coming out 75-80% regular… Decarbed

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But I would say your logic isnt flawed interily.

RSO suggests a long wash and all bioactive moelcules extracted more or less… But if you do a swift qwiso its still RSO? Or is it? If you use some carbon is it still rso? Or crc

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I’ve recently been tinkering with etoh extracts, Activated Carbon and Diatomaceous Earth depth filters in a Buchner.

I’ve taken some really dark extract and turned it to a light honey color with just the above. I shouldn’t be filtering out any cannabinoids, other than the loss that happens if you don’t flush the filter well enough.

The biggest change is the removal of chlorophyll. Before filtering you can see the chlorophyll fluoresce under a bright LED light I have, after there’s no fluorescence or very VERY little.

Just tossing the above out there, I’m just a wook doing this at home.


I wouldn’t use pentane for a diluent solvent for use w media. Sounds like a bad, more dangerous than necessary time.


What would be your recommended solvent for this process?



Heptane is your best choice

Pentane evaporates way too easily and its a pain to work with, you lose oil to your media this way

I would do this:

Decarb your crude oil, if you can get activated alumina fine grind is best here, sandblasting medium works great you can add this to your decarb step as it will reduce temps required for decarb and help pull undesirable compounds

Activated alumina is a cheap metallic compound that functions as a catalytic decarboxylation enhancer and needs to be used more often in that process because it drastically reduces energy consumption and degradation of your oil via reducing process temperature. Did i mention how cheap it is? Its like the cheapest adsorbent media at our disposal.

Decarb under vacuum with strong stirring let it cool with heavy stirring - if you want to reduce temps, oxidization, and subsequent degredation-
Do not drop temps under vac, bubble a stream of nitrogen through the oil with an el-bulliator as you stir.

Vacuum reduces heat transfer, you’re removing heat now but its hot and therefore reacting with oxygen at a higher rate- nitrogen is cheap gas! And its cold gas! liquid nitrogen is overkill obviously elbulliation vi nitrogen gas is a great little tool for cooling down your oil post decarb and blows a lot trashy fishy stinky vapor crap out with it that is normally trapped in the thick oil espntowards the cooler end of cool.

Once the temp of the oil has dropped to 67C, add 10% by weight bentonite clay and 5% by weight activated carbon and stir it hard, this is called a “hot scrub” which seems to be totally forgotten by most media companies- hot scrubbing with media during post decarb is AMAZINGLY effective because heat is a major factor in process efficiency! driving the rate of chemical reactions between the media and the oil, you need heat or some other energy input! (Ultrasound can be substituted for heat input in many situations but thats a whole new subject for another day)

the bentonite clay acts as a flocculation aid, essentially providing nucleation sites for fat/wax crystals to being forming on at a higher temp than without clay present- floccing fats and waxes is very well studied process and google is your friend if you want to really dig in there.

Okay back to process at hand:

Bring methanol to a boil at 65c atmospheric pressure - mix methanol with cannabis oil via slowly pouring oil into near boiling Solvent- you have to have the oil within 5 degrees C of your solvents boiling point for optimal dissolution.

bring the oil and methanol ratio to 8:1

8 parts methanol 1 part oil,

then add quarter part of water, stir it overnight, cool it but not nessescary to go super cold, refrigerator cold is fine- if you have time you can let it sit for three days and get the same effect of letting it sit in a chilled environment for 12 hours- cooling is not required for methanol winterization but it speeds it up a bit

At this point the bentonite will have flocculated any fats or waxes out and you will have winterized the oil well after filtering off any floating chunks of fats as detailed below:

Use a buchner funnel and make a stack of celite, bentonite, and top it with grainy coarse alumina If you can get activated alumina coarse grade is best here- it stops polar waxes like a brick wall which one needs to account for in terms
Lf filtering- you dont want a thick cake of wax to slow and clog your filter so adding surface area for your chunky waxes to hold onto means packing a top of filter media with stainless steel wool and mist the alumina and wool with water- which will make for a beautiful physical filter that wont clog up on you.

Pull the solution through the filter once,

If impatient or if you are scaling this process up- push the solvent rather than pull- use pressure from the top over suction from the bottom as the best you can do in terms of PSI is full vac which is 15PSI

Pushing means no real limit on psi, throw 10kpsi on pressure filtration and watch your filter cake blow up like a cannon- or dont… but 50psi pushing is likely fine - and % faster than sucking at 15 right?

Pour filtered methanol into tall container and add alkane
Use same amount of alkane of your starting undiluted oil. Eg 200g oil means 200ml alkane, you can double or triple the alkane if you esnt for ease of handling it just means more solvent to evap later.

Add a lot of salt water, like dilute the methanol down to a 10% ratio with water as you mix very well, pour off alkane, collect layer Load sep funnel, and use heptane to rinse the water and pick up any cannabinoids that didnt get louched to the first alkane rinse.

Your cannabinoids should be in your alkane now,
Rinse the alkne with ten volumes of salt brine that you have brought to ph8.5 using sodium bicarbonate

One volume at a time!

You arent gonna wash your 200g of oil with 2L of brine! You need to wash 200G of oil with 200ml of fresh brine, ten times! Shake shake shake!

Then rinse the alkane:oil solution with ten volumes of water one vol at a time, brought to ph3.5 with phosphoric or citric acid
Now wash the oil with as much ph7 neutral salt water brine as it requires to bring the oil to ph7
You cannot test the ph of the oil you have ti test the water that drains after you shAke it.

Every water wash has to be very well mixed.

You can dilute to 6:1 or so and pass the oil through a column of magsil for ultimate clarity but its an expensive extra step- if you want it clear though you have to use magsil as your final media

Evaporate the oil down, to ensure total purge once you think you have removed all the higher bp alkne you can add acetone to the oil and it will make an azeotrope with the hexane/heptane and purge very easily

Hexane especially likes to come off with acetone added so definately do this as you need to completely strip that hexane out it is bad news to consume
Check this paper out it talks about this acetone trick which i really like

Sounds like a lot of steps but there are ways to make it more efficently with LLE via a column

I hate shAking sep funnels but if it isnt a ton of oil to wash you are fine

You can use hexane for this process instead of heptane but beware it is neurotoxic and very nasty shit, if you are smelling the gasoline smell it means it is going into your brain so wear PPE!

Methanol also toxic but more as a bio-accumulator- it builds up over long term exposure and it can be mitigated a bit by have a small amount of ethanol jn your blood while handling it- sounds a weird saftey tip but there is enough methanol in every bottle of red wine and hard cider to sicken you a lot but the presence of ethanol in the blood keeps the methanol from being processed in the liver, it gets pissed out via the kidneys instead.

Either way best practice is not to inhale or let any solvent touch you!


I dont like to use a lot of charcoal as it tends to steal cannabinoids as well so the water washing steps later in the process remove any water soluble compounds that the charcoal misses.


Interesting comment…
that amount of alcohol knowledge doesn’t come overnight.

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If you go to the ER with acute methanol poisoning they put you on an ethanol IV and get you instantly drunk as shit to save your liver.

Any pectin rich fruit mash like wine or apples or strawberry, blackberry, etc have proportionally higher methanol content, pectin ferments into methanol, any stems that make it into the mash create methanol- its wood alcohol after all!

So when you distill a liquor made from fruited beer your methanol heads fraction is considerably larger than say a vodka made from potato or a rum made from sugarcane juice


I was referring to the proposed clean up outline.
But I also noticed the toxicity references and good advice.

The ethanol in ER is good for the antifreeze drinkers as well.


These videos are great educational tools for helping employees understand and respect various solvent toxicity, chunbyemu makes entertaining content that is highly educational i recommend any lab operator to make people spend time on this channel

There are plenty more

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