Filtering help needed

I’m hoping I can get some help with an issue Im have.

I did an ethanol wash on some hand trim. Put ethanol in freezer and trim for 1 week, then into dry ice cooler for an hr or so. Did my wash using a 160iu bag using the quick method. (See roasting pan pic for color). Started to filter theu buchner funnel with aluminum oxide (1/2") and vac assisted with my welch diaphram pump.

The 1st Mason jar came out good. The 2nd Mason jar came out green. I did screw up, I let the work bag drain in a 5gal bucket, and I dumped the drained ethanol (albeit dark green as crap, I should have known better). I only got about 1oz liquid total of the dark green ethanol from the work bag. I added that to jar #2 and it tinted up badly.

I’ve filtered this green tinted ethanol 4x already with fresh A/O all it being super cold in the dry ice to no better color.

Not sure what else to do, if anything.

Items on deck
celite 545
4 buchner filter setups

Bottom pic in below text is the green tint nightmare.

Going back over it in my head I know I screwed up by penny pinching the last bit of ethanol that seeped from the work bag. NEVER again. Really hope I can salvage the 1600ml of tinted ethaol vs dumping it.

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Hello Demontrich. Have you considered using activated charcoal? You could have yield loss due to the charcoal grabbing some cannabinoids but it remove the green pigment (presumably chlorophyll).

PS: Use a lid on your jars next time you winterize with dry ice. Looks like your ethanol solution had co2 bubbles in it. Your ethanol is at least 5% water and will react with co2 to form carbonic acid. It could make your extract acidic and cause unwanted isomerization when you distill the ethanol.

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Interesting point on the carbonic acid, I always add dry ice to my solution when winterizing and still achieve +85% d9.


Do you carbon filter? Also are you saying you yield 85%+ of the total cannabinoids or the potency is 85%+?

I do carbon scrub and have noticed isomerization after distillation without neutralizing the crude. 85% d9 90+ cannabinoids

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It better not have any water in it, or I’ll go back to buying 190 proof. Much cheaper than the 200 proof.

I’ll give the AC a shot tomorrow. I’ll do room temperature before the 145f water bath step and see if that fixes it.

Much appreciated.

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Neutralization is a step I think a lot of people undervalue. Isomerization goes frequently undetected unless the distillate turns pink (acidic) or purple (alkaline).

Would you mind giving your input in another thread that I have been discussing charcoal filtration loss in? (link below) I think there is a misconception about how charcoal grabs a ton of cannabinoids.

Link: General Distillate Questions - #57 by Naturalascent


Id bet you a beer that your ethanol has 5% or more water in it. Especially if you placing it in dry ice freezer without a lid. Ethanol loves water and will absorb the moisture from the air. Dry ice attracts a lot of moisture. Even when I used a3 molecular sieves to remove the water from ethanol it was only a matter of time before it went back to its azeotropic ratio. A cheep and quick test of the ethanol’s purity can be checked by density. Tare a graduated cylinder on a scale. Add 10ml to the cylinder and record the weight. Divide the weight by 10 and you will get the density. Not super accurate but good enough for rough estimates. Any value above 0.79 g/ml and your ethanol has water in it.


Understood about it absorbing h20. I’ve been dealing with another 5 day migraine. I’m just not recovering from it. I’ve also been reading your general distillate thread as well.

Anyone have any thoughts on doing a room temp AC scrub, or go the 60c warm water bath method?

I’ve been experimenting with room temp carbon scrubs. So far it seems that acid activated carbon is not very efficient at removing pigments without the addition of heat. That said, Ive gotten decent results doing multiple room temp scrubs.

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I’m gonna try the warm water soak for 30 mins then filter.
Fingers crossed or it just gonna be used for edibles after evap and purge

Filtering now. Seems to have worked, but at what cost to potency.

Thank you for all the help everyone!
I used celite 545 as well


Im glad it worked! A large difference too. Did you rinse with plenty of warm/hot ethanol after charcoal filtration? If your worried about pigments coming off the charcoal swap the collection flask. You can always use the pigmented rinse for edibles. Its important to realize that colors are just pigments and just a poor indicator for potency. Ive made black shatter that tested in the 90%'s range as well as made gold tinted translucent extract that tested in the 70%'s range. If you ever do test the ethanol density let me know the result.


looking good!

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I bought a graduated cylinder and an alcohol proof gauge. I’ll check it after I run this thru my table top. My 5l rotovap isnt set up for use yet.

Thanks again everyone for the help and what not! I wish i took other avenues in life. I absolutely LOVE science and chemistry. Too bad I’m 43 now and made other life decisions.


try silica 60 staged ontop of celite, you may like that better.


I think a room temp carbon and celite acub may have worked as well as the warm water etoh scrub. Just from how it cleaned up my other jar as well.

I’ll order some silica 60 today and keep it on hand.
Edit: silica 60 is pretty pricey. Ouch.

Thanks again!

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Looks good, glad it worked. What temps did you end up trying? and how long did you leave the carbon in?

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Temp 63c
30 mins soak in hot water bath

I think I used too much ac, less may have worked better. Learn as I go I suppose. I have my machine trim to run next.

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