Winterizing BHO Crude without purging in Oven


I have recently figured that the bho shatter Im making into distillate probably does not need to be purged in ovens for 3 days to remove the butane. I was wondering if other than mixing the crude oil in an ethanol mixture and heating, if there is any other post processing required to remove all remaining butane prior to rotary evaporating?

I am currently decarbing on a hotplate until I can purchase ovens I can both purge and decarb at a steady 140 for about an hour. Anyone have any experience in polishing crude right out of the closed loop?

Thanks guys

How much you extracting?

Honestly I got one of these before a vacuum oven and it helped me a lot when I was only blasting 2 Oz with my closed column.

Closed loop and larger extractions I would just say save for an oven

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I spray staright into stock pots and add etho it will be completely dissolved and room temp filtered with in hours of comin out of machine

you can take your crude directly from the closed loop and add it right to alcohol and start your winterization…no need to purge. You will need to kinda have a baseline yield for your material.

Let just say im running crude in my extractor. im running 2.5lb runs and the material pops off 10% yeild… I will pour that 110G or so directly into a liter or so of everclear. Rough filter it once in the buchner then right into the freezer for more winterization before distillation.


I do something similar. I’ll have a jar with x amount of alcohol weighed beforehand. I’ll do my pour into the alcohol and weight it after it settles and add more alcohol as needed


It would be exaggerating to claim there were no new questions…

BUT, chances are anything you run into has already been seen by someone else here, and there will be clues in abundance, if not the exact answer you seek.

So, the first rule of GLG is use the @*#$^($#@)(#@ing search bar :wink:


out of the CLS?

nah, the current state of the art is to polish IN the CLS: Indofabs C.R.C & BHO Color Remediation Tek


I know you can ahieve this with a dewaxer and running cryo, but unfortunately my lab isn’t going to pay for that chiller or freezer capacity

Blasting around 40lb of trim in a day.

Hardware Factory Store has a vacuum oven for a little over 1,000$.

I believe when you add in a winterizing solvent like ethanol it will “kick out” the butane molecules via some soluablity property. If I’m incorrect please let me know!

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@Cheecharoni yes the butane leaves when you add ethanol.

no, it is not “some solubility thing”.

its a boiling point thing. butane boils at about 0oC. so as soon as you lower the viscosity of your extract to the point it can leave, it will (assuming you’re above it’s boiling point).

heating the extract up, and lowering the boiling point of butane achieves the same thing (in your vac oven).


if you can make sure your trim is frozen right after being trimmed, then invest in a couple coils and stick them in dry ice and alcohol and you wont even need to dewax… trim runs will be looking like nug runs real quick

Just wanted to add a quick lesson that I just learned (almost the hard way) today. So I was under the assumption that butane would leave when you winterized, filtered, evaporated, and decarbed the oil before distilling. We seal our decarbed oil in steel clamped containers. Normally when hot decarbed oil is put in them and sealed, it cools and creates a vacuum, when coming from an ethanol extraction pathway. Well on the butane experiment I just concluded, this was not the case. The vessel built up a lot of pressure which sent the steel cap flying past my face and landing across the lab, as soon as I began to loosen the clamp… Now, I was skeptical that butane did this, but when I began to use heat to remove the crude from the container, it was obvious that butane was still present, as it began to off-gas with little heat being added. Thus, against all my chemical intuition, butane does stay in residual amounts, even after decarbing. Not saying this is an absolute and this will happen every time, but do not be so quick to assume butane is gone without proper purging. Stay safe friends.

You should never seal up any container after heating a mixture with solvent in it. Thermal expansion will happen. Temp increases so does pressure. If you need to seal immedatly don’t do it. This could of been a potetional serious injury. Y’all lucked out. Buy a tiny bleeder valve to off gas. Such as a needle valve. Or pressure relief valve. Make sure y’all write this down on a safety Manuel on this incident so y’all can have one for new hires. Best of luck sir

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Whenever you take your crude oil out of a rotorvaporor or your decarbed method they will always have solvent in it. Even micro amounts. This happened now because you didn’t take as much solvent out as previous times. If you want to verify this it’s easy. After it settles. Reheat the mixture the next day after it’s been cooled. Watch for the bubbles after the top layer of water vapor gases off. Whip the shit out of it manual while heated. you will see a few bubbles come up. That’s solvent bro.

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Yeah no kidding… I am certainly aware of this reaction but it was my oversight to teach down the line effectively, I suppose. It is certainly getting super double bold XL underlined in the SOP as we speak.

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Everybody made it home safely. That’s what really counts. This industry is young and we’re writing the guidelines for it. They will have more obstacles ahead. I always say shit happens and there is nothing we can do about it but how we react to it is what matters.

I decarb large batches to then store for the week or so all bho crude, ive never had any solvent survive 140c under vacuum. I will have my first 50 mls tested to see what it is. I have even left those flasks out overnight and day and its nust waywr and terps, i put in freezer just to see and the water froze so all that was left was terps

Have you tried reheating at 140 the next day and manual whip it? The test will come back with solvent. Basically a thin film first run is the only way to get all the solvent out . What is your decarb method? Is it getting magnetically stirred under vacuum?