Yes, I’m also confused how you could do chromatography when you’re only feeding extract solution. Usually, you add a “slug” of analyte and then push that through with fresh solvent. If you’re always adding more analyte you’ll always be adding more of the stuff you’re trying to get to the bottom of the column into the top.
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this is how you would do it.
otherwise we are not thinking outside the box, or whatever we’re chasing isn’t “chromatography”
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Unless you use a very sticky mobile phase and a shitload of solvent which sounds terrible in every regard.
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Dunno if you saw this or not, but @Graywolf documented a session of @murphymurri and her technique.
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So it’s just good old fashion patience. Recovering each fraction separately.
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In addition to the media(s), we’ve got solvent/blend and temp we can play with…and both of those are clearly being manipulated.
Perhaps there is a “none shall pass” media/solvent/temp combo that could be used to achieve what I think I’m looking for.
Definitely not going to turn one of these down, just not gonna advise folks to base their production technique on something that I haven’t first wrapped my head all the way around. That usually requires at least some smaller scale R&D.
I don’t consider an EX-80 small in the thc world, but I guess it probably qualifies in the hemp world.
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I did, and rereading I noticed that the nominal 5lb PX1 was loaded with a “partial sock” 
I still don’t see how one can get “the terpenes first” when there should still be terpenes in the reservoir above the media until there is nothing but vapor there.
Then we elute those with fresh solvent?!?
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This is what my brain tells me too.
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and I’ve got no problem with that part, except we then need a high enough bed volume/great enough depth, and a shit ton more solvent that doesn’t go through the material column to elute all the other fractions.
which seems achievable. just not sure it makes sense at my scale.
without playing with it, I’m not even sure what “my scale” even looks like. So I’m sure as hell not going to say “yeah, buy 4 of those!” (cause they look too small to me).
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Yeah so @Roguelab shared some info with me about 3A zeolites and acidic cannabinoids which might make for an interesting in-line THC remediation process but it would require a second solvent which would have to be aromatic and I’m guessing that would turn most people off. Probably more solvent friendly and certainly more media cost friendly than RPLC but a bit more involved to build the skid/validate the process.
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Hey guys. Long time scroller first time poster. Just made this account. So I dont wanna write a huge post if it doesn’t necessarily belong here. So in simple terms im running a closed loop active emotek system. Running 70/30. Just added a little crc inline and using these “disposable” cups that fit in the cylinder column. Im r and d ing it myself and was wondering if anyone had any tips on packing the media powders, what order they should go in, pressing the media?!, should it be warm?, 3 weeks into crc tech and im looking for a little guidance. All tips appreciated thanks for reading.
There’s about a million posts on here that you should read until your eyes bleed but here’s the TLDR for your questions:
Adsorption happens better at higher temp. The rest of your process probably works worse at higher temp. Design your process accordingly.
Order of powders isn’t particularly impactful in my opinion, other than DE goes on the bottom to keep the other dirt from going through. I prefer to put B80 or other media that you use a lot of above the stuff you don’t (sil-60/AC).
Pack your media tight and under vacuum if you can. Priming with liquid solvent can make it less likely to channel. Obviously avoid any backwards flow of solvent that could unseat the dirts
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About how much vacuum and heat do you suggest?
Ready for some vague answers:
Enough vacuum to make the dirt sit down tight (not much needed really)
Warmer is better through the dirt but obviously the solvent needs to stay liquid. Vague answer number two is as warm as you can get it without making your extraction warm or the pressure differential too low to have a good flow through the dirt
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Whats your opinion on vacing and heating my crc cup in the oven before my run?
Nope. Now we’re just scrubbing 
Which is how I plan on implementing for production till I wrap my head around doing actual chroma.
@SierraXtracts you’re using color remediation cups. Probably not doing chromatography.
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I think the key point being missed here is that you MUST reduce your solution after extraction BEFORE chromatography. You dont have to pour it out of your extractor to do this, but you’ve got to reduce it down to just barely enough solvent to move the solution via hoses, and no more. This will allow you to move your entire sample (batch) into the column all at once.
You can boil it down in you collection vessel/separator before moving it to your chromatography column, or in another heated column that you build for this exact purpose. Either way, I will never recommend putting media directly below your material column because you cannot prep the media or reduce your solution first if you do this - and those are both incredibly important steps in this process.
If you cannot move your entire batch into the column at once, with the appropriate ratio of oil to media (which is measured in volume/retention time - not weight!) then you will not be able to pull fractions. Dont worry though - you can still use different solvent blends and temperatures to influence elution to achieve higher purity. That just isn’t technically column chromatography anymore, and more like batched sediment bed filtration. When done properly, sediment bed filtration will still dehydrate your oil (remove water) and eliminate solids including plant material, dirt/clay, random particulates and heavy metals. (anybody every dropped a jar before? sediment bed filtration is a great way to remove tiny glass particles without affecting your oil quality or yield! crisis averted lol) If you are unable to pull fractions, I would recommend sticking with the dehydrating medias like large porous clays instead of spending the extra money on silica, magsil, or chromatography grade alumina. If you’re not pulling unique fractions many of the things that make adsorbents useful become impossible to control, and you could actually end up with concentrated astringent-butt-flavored oil because things like sulfur and chalky waxes will still come out of the column and will dilute the otherwise high purity you’ve achieved through dehydration/sediment bed filtration.
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Thanks so much for sharing!! Its all become so (aqua) clear now!
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Ah, now that makes sense. That is indeed chromatography.
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Thank you @murphymurri!!
Yeah, that did come up early in the discussion. Did not see it covered in the graywolfslair write up.
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