Reverse Chromatography THC remediation

Hi all,

Have been lurking for a bit and truly appreciate all the information and help offered by so many knowledgeable folks here!
I am starting a lab and will be extracting hemp. I realize that THC remediation will be a necessity component of post-processing.
With that being said — and without having a big budget — I came upon reverse chrom to achieve my goals.
So Im hoping to get help with the actual procedure if anyones willing.

I know that c18 silica is likely best stationary phase media (though im open to hear about cheaper alternatives).

The real question is what ratio of ethanol:water( open to other options) for the mobile phase — and how to set up the gradient to best elute cbd and retain thc. If anyone has good experience with dcvc for this exact purpose— would love to run this as a dcvc method.

Am aware of normal phase methods but they best apply to high thc low cbd oils if Im understanding this correctly.

Cheers all and thx in advance

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Normal phase stationary media is more polar and better for retaining polar compounds, which THC is not

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To develop your mobile phase ratios, run some thin layer chromatography experiments with varying proportions of mobile phase

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Also, not being a dick, but you kinda need a descent budget to run preparative scale chromatography

This is not an area you want to cheap out on

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If you have a low budget you should go with isolation and make ≤99.8% CBD isolate. Easy and cheap. And there’s like a billion different ways to get there depending on your exact budget and starting material

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Point taken. Appreciate the input.
I definitely plan on doing tlc as part of bench chem to help figure things out…

I understand that cbd is more polar than thc, but also from what Im understanding: Because theres so much more cbd than thc in the oil … that normal phase chrom would not accomplish separation efficiently // or that some thc may be left behind… if this is not the case or if theres a way to mitigate this issue Im all ears. Would much prefer normal phase

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Why do you CBD more polar?

THC and CBD have the same molecular weight, formula, and similar structure. They’re isomers. They both are pretty non-polar.

Because it has 2 -OH groups to 1 for thc…

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Yes, and THC has an ether group with two lone pairs on the oxygen in place of one of those OH- groups, so I don’t think there is a huge difference in polarity, certainly not enough that a normal (polar) phase is warranted for separation. Fact remains both molecules are predominately non-polar

Sure … I was figuring that Id have to use reverse phase so your statement is another confirmation of this, correct?

Reverse phase my friend

Agreed. If u refer to my initial post - I discuss using c18 silica … i was already assuming reverse phase.
If u have any contacts for more economical c18 welcome to hear them.

Try @Shadownaught, he’s a trusted source for that and many other lab consumables.

Yessir, we do supply c18 at our best attempt of market leading rates. Thanks for the shout out

@cbdneo

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Note: there is a chromatographically exploitable difference between cbd and thc

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Edit your post, did you mean not that scalable?

Hplc is difficult to scale unless you have alot of millions

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Indeed, the HPLC reverse phase method I used the retention time for cbd was about 2 minutes and for thc about 3.7 minutes, great resolution (separations) with clear peak lift off and touch down , no shoulders or any weird stuff. Highly reproducible and scales in a linear fashion for transferring the method from analytical to preparative scale @QGA

So once you have your method dialed in with the analytical system and you’ve determined your column loading capacity on that c18 media, you can transfer the method from an analytical system to a preparative system and because of the linearity you can extrapolate your column loading capacity on the big prep column (same c18 media). Solvent consumption should also increase in a linear fashion so you can ascertain how many column volumes of solvent required for target analyte to elute from the big c18 prep column

Sorry original post was confusing - cant edit it for some reason - will delete it to prevent confusion

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Solvent management is the key. The equipment and storage to handle the amount of solvent gets costly, very quickly.

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I offer THC remediation services. If you look at the ROI it is much more profitable to invest in oil/isolate manufacturing and outsource to a 3rd party for THC remediation because chromatography is so expensive and time consuming. THC remediation is our specialty, we have top of the line equipment and advanced methodology.

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What makes you think that carbon oxygen bonds are the same polarity as hydrogen oxygen bonds

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