CBleach Scrub

For those of you asking about the carbon scrub SOP, I follow the Instructions from ColumboLabs and I basically only use CBleach now.

Wet Bleaching

After full winterization,

  1. In a well ventilated area or fume hood, heat alcohol/oleoresin suspension to 80c (Just above the boiling point of ethanol and isopropanol).
  2. Measure 5% of total material volume in CBleach and slowly add to boiling suspension. (1000g oleoresin : 50g CBleach)
  3. Stir for 10-15 minutes while maintaining a minimum of 60C temperature.
  4. Allow solution to cool to approximately 40c and filter through silica over filter funnel

Does this method cause much isomerization of d9 THC?

What kinda Silica? How much silica? I seem to have loss in my bleaching and i think it’s in my filter


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I have always done a carbon scrub room temp or cold. Has anyone done a side-by-side filtering the same material at different temperatures? I noticed some SOPs say DO NOT carbon filter cold. Is this due to a loss of cannabinoids?


The carbon scrubbing is more effective warm. Also its better to use a mix like CBleach vs straight carbon


Cool, thanks man. Do you have any sources or data for that? I have seen some sources (mostly for water treatment) saying that adsorption decreases with temperature after a certain point, so I assumed it would be similar for oil in alcohol. This system is also more complicated since we are very concerned with losing our active ingredient(s). I suppose we would want to optimize (contaminants removed) / (THC removed), or really some balance between potency (+ color) vs. yield. There should be an optimal temp that maximizes both for a desired outcome (distillate vs.oil vs shatter)

For filtering straight distillate or crude, of course it must be hot, but in alcohol, I’m not convinced yet. It wouldn’t be too hard to test, but I don’t need to reinvent the wheel if I don’t have to. Potency and yield would be enough to test this.

For the CBleach, what does the clay do other than help filtration? Are you affiliated with them at all?

Oh, and thanks for the data dump! It got me on here for sure.


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After some research, it looks like for physical adsorption, which I’m assuming is what is happening when carbon filtering, adsorption decreases with temp. (This makes sense, think of heat as molecules vibrating faster and bouncing around)

For chemical adsorption, it increases to a point, then decreases.

(Sorry I cant post links or pics yet)

So we can assume increasing temperature decreases both contaminants and THC picked up by the carbon. Maybe this doesn’t matter though, because we can always just use more carbon. The question becomes: Which is affected more by temperature, contaminants or THC? It might take more than 1 or 2 lab tests to find this optimal temp. Anyone done this yet?

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According to this study, carbon worked better at adsorbing dyes when it was hotter…



Good find. It almost sounds like they were surprised by the finding though, expecting physical adsoprtion to be exothermic when in this system it was endothermic. They even say that it is “uncommon” to be endothermic. Also, it looks like this is an aqueous rather an organic solvent system, so that might change things too.

I would still argue that adsorption of impurities (or pigments) with respect to THC adsorbed would be more important than adsoprtion per surface area of carbon. You can always add more carbon, but sacrificing THC either by adsorption or degradation by heat should be minimized.

I don’t know the right answer, but this is something I’ve thought about but not had the time to dive into.


I like the mixed adsorbents. In my experience, a proper mix does a better job of stripping color without grabbing too much THC.

This would be a great experiment to document and turn into another paper!


ive used activated carbon many times for fermented drinks like beer mead and its always said to at least warm it at some point. it being in ethanol instead of h2o wouldnt make a difference i dont think since its a physical process not a chemical one. molecular sieves release energy when absorbing water so i can see why there were suprized

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everytime i see cbleach in ur post i read it as chlorine bleach lol i saw it off hand in other post where u didnt link it and i was so confused

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How is this different from the carbon and silica I get from Summit?

This also has fullers clay to adsorb some of the pigments at higher temps.

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Thats just a brand name. Bleaching clay still sounds like something you might use to sandblast paint off a house…but that would be the technical term.

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A snippet of what remediation bleaching clays are used for:

“Gives edible oil a long storage life and makes it heat resistant as well as neutral in taste and odor. All undesired substances, like gums, dyes, peroxides, heavy metals, and residues of crop protectants, have to be removed from edible oil whilst preserving the nutrients.”

We carry several versions of clay products in order to offer bentonite with these properties to the industry. Stripping oleoresins of contamination isn’t 100% analogous to the edible oil process…but it can certainly be argued that we’ve had some success generating parallel methods to access similar benefit.


Tall oil and edible oil have been my most beneficial sources of outside industry analogies


What would be the benefits of using MAgSil-PR instead of Cbleach, or should both be used?