Chromatography Units for CBD Isolation

Ctech glass sells a great little LC tube for about $65 I have used many times these last few years. I got the ¾ diameter unit. I also own two tall form buchner style quick sep funnels for taking the ideas tested manually on the small LC tube and scaling them to preping my medicine. For me this means I scaled up to one ounce in capacity from the small.

I use the process only for prep to refine D9 but the concept generally follows the same path as for any LC chromatography seperation.

You must choose from several parameters but chiefly what your stationary phase type will be (alumina, sand, silica gel, Magnesium Silicate, ect.). Then you must decide if generally less expensive standard phase or more expensive reverse phase is needed. Standard phase chromatography to me means that more polar solvents will more easily move compound off the stationary phase as it passes, so a solvent like Ethyl Acetate (a polar solvent) will easily move cannabinoids but Hexane (a non polar solvent and hydrocarbon) will barely budge cannabinoids off the stationary phase. Reverse phase is simply the opposite relationship but as a rule the stationary phase is much more expensive then (C18 silica gel is a reverse phase gel while silica 60 is standard phase).

Once you decide standard or reverse phase then your choice is to pull the solvent through the column using gravity (standard Liquid Chromatography), push the solvent through with pressure from above (Flash Chromatography), or pull by vacuum from below (Vacuum Chromatography). Your column choice dictates this. My personal fave is Dry Column Vacuum Chromatography. Dry Column is only available in Vacuum Chromatography flavors but can process MUCH more bulk less expensively than others.

Finally you must choose whether you will run the same solvent mix during the entire run (called an isocratic mobile phase) or whether you want the flexibility but more complex method of varying the mix ratio of any solvents used during the run (called a gradient mobile phase). DCVC shines when a gradient is selected but can be run in isocratic mode too. It just does not seperate nearly as well imo.

Good luck with your efforts. I have found learning chromatography to be an intuitive process once the words are defined. Actually the biggest hurdle is just learning what the words mean and not what is actually going on - essentially you are washing a “stain” through a column that some parts of the stain need stronger solvent to wash through than other parts and the parts are collected as they leave the column (often said as “elute from the column”).

Guren Tag! :nerd_face:

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