EHO Color Remediation

I tried making my own t41 using hwc and ac mixed at different ratios with t5 but couldnt get the same results as using prebought t41
Sometimes to do with the um difference

That and the pH differences between the medias you used to recreate it and its own pH of 3. pH of the media and solvent play a large role in these processes.

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Shadow mentioned the um thing to me. T5 and ac having different size um. As per t41 being the same or close to the same consistency

The similar particle sizes is important for keeping a good mix if I’m not mistaken. Think about how shake ends up at the bottom of the bag, but large bits end up on top as things move around. No matter how hard you tried to get them mixed evenly, the carbon would want to end up at thre bottom.

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I got it to look ok, but it did work the same.
I nvr tried to shake it to see which would separate

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Filtration through AC and T5 should be all you need. I use it regularly and am super happy with the results. I make a slurry of the bentonite with ethanol to make the puck (on 6" filter plates). I then do the same thing with the AC (we use hardwood). 1/2" to 3/4" for the bentonite layer and 1/8" for the AC. Seems to do a bit better when we filter cold but have achieved the same results with warm filtration as well. This is what 3 passes should get you:

Edit: Spelling and grammar! Really need to proof read better sometimes. Haha

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Oh, wow. In etoh?

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Those results seem awfully remarkable. Can you run us through your extraction process? Cleaner input equals cleaner output so I’m assuming you have a fairly clean starting extract.

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Very green, very little of much else.

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Do you have any idea of your yields/potency/efficiency/losses in your filtration?

Hugely impressed with the work if you’ve been able to mitigate cannabanoid loss!

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@Krative, yes. We use only 190 proof organic ethanol.

@CuriousChemist22, we absolutely do our best to extract as cleanly and efficiently as possible. We currently extract with a CUP15 and are limited to one -40C freezer.

We prechill (down to -40) 15 gallons of ethanol, 15 gallons of isopropanol (for a cryo-bath), and all of the biomass to be extracted. After setting up the equipment, the iso is removed from the freezer and poured into an insulated htpe container that will also accommodate a keg. We then add 15 or so lbs of dry ice to the iso and put in the keg of prechilled ethanol.

We then run the CUP on 10 minute agitation cycles, and we typically run at least 4 rounds of biomass through the same ethanol, bringing us closer (but never to) critical saturation. I am sure we are leaving cannabinoids behind, most especially on the later runs, but we seem to achieve really nice yields. We constantly add dry ice to the cryo-bath and give it a bit of time to rechill the ethanol between runs. Sometimes if the room is too hot we even add dry ice directly to the ethanol (with no discovered ill effects).

After extracting cold, we filter cold. We build out custom filter stacks with tri-clamps and filter plates. We start with a single coffee filter (20um), then down to 10um, then 1.5, then the AC and T5 bentonite.

What you see in the above picture was the result of a whole-harvested hemp extraction that started out around -40 but probably finished at closer to -20. We filtered like we used to (just down to 1.5um) then did three passes through the AC and T5 puck. I currently build out a filter stack that has 3 of the pucks, making only one pass suitable for this type of result with only a third of the time. When the ethanol is removed, there is definitely still color. The end result is a beautiful golden blonde.

A while back, @TheLostBiologist was kind enough to chat with me about his process before he posted his incredibly detailed (and highly recommended) SOP. I have merely scaled his filtration process and worked it into our daily practices. If any of you haven’t read it, please do. It is worth your time.

@tweedledew, I wish I had exact numbers to throw back to you, but our GC is a finicky sob and a few people have worked to destroy the column a few times, despite @cyclopath’s best efforts to fix him. We have, however, tested our tincture pre and post filtration and not noticed any significant loss of cannabinoids or terpenes (those aren’t measured by our GC, just our noses). All we seem to be losing are undesirables. Our yields are closely tied with our biomass potency. Those two numbers tend to sit within a few percentage points of each other. On the low end, we can yield around 12%, and on the high end we’ve seen 22% (on beautiful flower-only extractions). Our potency tends to sit in the mid sixties with frequent jumps into the seventies. We even received a COA that put us at 81%! Though, I really don’t trust the lab that gave the result on that one, it was still exciting to see. Haha. As for the efficiency, I haven’t done the math, but we’re doing well enough with it to not really care too much.

I think the trick lies with not having too much AC for keeping your cannabinoids. We have seen that a thick enough puck of AC will absolutely strip cannabinoids. I haven’t wanted to see how thick I can make the puck before losing cannabinoids because we couldn’t ever afford to lose any. This tek works. It works really well! Filtering cold seems to help too. We can achieve good results filtering ambient temp tincture, but nothing like we get when it is cold.

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First of all thank you for the detailed response. That really helps.

So it sounds like my process is likely just failing to maintain those temperatures and as such pulling outrageous amounts of undesirables. To keep everything cold during filtration is your filter stack jacketed or insulated in some fashion?

Also the CUP is designed to reduce very small plant material in your starting solution, right? Perhaps I’m carrying too much plant material into my very slow filtration at 25um and that’s further extracting into my solution.

We’ve been using TLB’s tech with only minor modifications to the filtration step similar to what you mentioned. Does passing over carbon several times, but in small amounts… you did 3 passes… prevent the carbon from being able to adsorb cannabinoids? I’ve been concerned using too much carbon, cumulatively, would have the same affect as using too much in one step.

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You are very welcome @CuriousChemist22. Sharing is caring!

For keeping it cold during filtration, we do not utilize any jacketing but we do have insulated hoses. We keep the freshly extracted tincture in the cryo-bath so that it is only warming when actively filtering. We nitrogen assist to speed the process up. Vacuum seems to not work as well.

As to your question about the CUP, I’m not sure I understand exactly what you mean. The bags utilized in the CUP are 80um, I believe, so my tincture is only polluted with mostly kief and other small particulate. There is often a lot of it too.

If you are filtering a slurry of biomass and ethanol and not just tincture, I would suggest utilizing as big of a sock filter as you can muster at 150 or so microns. The longer (and from the sound of it warmer) your biomass is in contact with the solvent, the more it will pull. Sock filters (or even cheesecloth) should allow you to remove enough biomass from the solution to speed up the filtration.

I, sadly, do not have a more specific answer for you as to why a thin layer of AC passed over multiple times pulls far less cannabinoids than a 3x thick AC puck would do in one pass. Perhaps @Photon_noir and/or @cyclopath would have a better answer.

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I’ve always found that color can be varied with extraction temperature, residence time, and filtration. The warmer and longer the soak and the less thorough the filtration the darker the oil. The colder and shorter the soak and the more fine the filtration the cleaner it will be. Color is not the only factor. Taste, for instance, is directly attributable to the same factors. Sadly, yeild is inversely tied to these factors as well. Shorter, colder soaks will yeild less of your target but at a higher quality. It’s all about trade offs and goals. If you’re looking for a high end smokeable dab then you’re going to want super cold (-80c) and super short. If you’re looking for an edible oil then you can go longer and warmer (say -60c). Crude longer and warmer still. I do -80c for 3 minutes for dab products followed by a 5 minute soak, again at -80c for a full spectrum vape quality oil. If I’m just making a vape oil and not taking a super premium cut I’ll do -80c and run for 8 minutes straight through. No matter the soak time I always do a 15 minute warm soak on the spent material. Our average extraction yeild by weight over all soaks is about 22%, usually ending up in the high 70%s to high 80% in potency. We use the same filteration steps for all soaks.

I know the common thought is that carbon destroys yeilds. I have mad love for my boy @Akoyeh, but I just haven’t experienced that. I’ve gone as far as to throw AC directly into extract for up to 15 minutes followed by filteration over bentonite and never saw a significant deviation from our typical yeilds or concentrations. Still, you’ll want to go light on the AC layer in the cake if for no other reason than time. AC is super fine and will slow down filteration speed.

That having been said, because it’s been a non factor for me I haven’t done any amount of rigorous testing on the issue. I’ve never done a run side by side with the same material, controls, or experimental models. Maybe @Akoyeh can fill us in on what he was seeing to bring him to that conclusion.

I’ve never definitively said that AC won’t adsorb cannabinoids. Again, I haven’t put any time into testing, so I can’t say that conclusively. My point is that if it does suck up your target compounds it is doing it at a much slower rate than it is sucking up all the undesirables. The net result is cleaner, clearer oil.

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I agree. I have even let winterization solution sit on 5% AC overnight without seeing any real yield reduction. I think carbons ability to absorb cannabinoids has been greatly exaggerated. I mean I’m sure it does, but at reasonable levels I haven’t seen it do any harm.

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Good stuff gets stuck, rinse it out. Bing bang boom.

The pore sizes prefer chlorophyll. Like any reaction it’s imperfect, so you’ll get some loss, but I think it’s way overstated.

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I would also recomend to all
To try to find a different filter aid than a buchner funnel
Deu to their size we use to much filter aids
For the volume we want to filter
A smaller filter plate in diameter needs less filtermedia and iT is Packed thicker
I. Personaly now use crc type of columns as my filter appparatus

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Cold filtration makes sense I think. Ethanol acts less polar the colder it is. The clays work best with non polar solvents.

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I do not have any empirically validating data to back up the idea that AC will strip cannabinoids. My former employer had had it happen to some of his earlier experiments when using AC as a filtration tool in large quantities. Again, having not been able to afford the loss of cannabinoids, I never got the chance to experiment. When we saw it worked and there were negligible losses, we went with it.

Maybe it’s just another old wives’ tale. Probably has some validity. Hopefully one of these days I get a chance to figure it out.

Edit: Damn spelling, again.

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Cold filtration makes sense I think. Ethanol acts less polar the colder it is. The clays work best with non polar solvents.

I don’t think it’s so much that ethanol acts nonpolar when cold. After all if it was nonpolar when colder, it would be more liable to extract waxes, which is the opposite of what we actually see. The answer is that when using carbon, there is an equilibrium: carbon is constantly adsorbing chlorophyll out of the ethanol, and ethanol is constantly extracting chlorophyll from the carbon. Therefore the weaker the solvent, for the compound of interest, the more the equilibrium will lie with the adsorbent. This is the same reason they generally work better with nonpolars, because the Van der Waals forces that they solvate with are much weaker than the hydrogen bonding ethanol has.

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