This started as dark brown concentrate testing 65% nominal cannabinoid. The crude was dissolved into hexane and then wet loaded on top of a used column. I load it right on top of the Celite 545 layer (Amazon) from a dry loaded run. The Celite layer works GREAT when wet loading a bunch. This run started at one ounce. The column handled it with zero problems. This run was not dewaxed or processed at all prior to this first run.
The solvent system is generally Ethyl Acetate and Hexane starting with hexane alone. Then the Ethyl Acetate is added in 5% increments and is collected 20ml fractions at a time. Once the gradient is over about 30% Ethyl Acetate to hexane the majority of wanted fractions have eluted. Then I add Ethyl Acetate alone along with methanol to move the waxes and chlorophyls and just general gunk off the column. The cannabinoid fractions can be identified visually. They always elute after the highly colored bright yellow (or bright orange according to starting strain) fractions and at about fraction six the cannabinoids are seen in the test tubes as the brown fractions between the bright yellow first fractions and the green and later fractions.
Here is the starting crude dissolving in hexane.
Here is the crude now wet loaded onto a previously used column. The compound is loaded on top of Celite used in a previous lab as a dry loading agent. Wet loading allows much larger quantities to run. Dry loading can resolve close fractions better imo. The Celite layer is on top of the standard chromatography silica gel 60 A pore, 35-75 micron from Analtech (Amazon).
Here is the column now just as the cannabinoids are getting ready to elute and are followed above them by the green chlorophyls. The green chlorophyls always elute well after the cannabinoid and take much more polar solvent to move off the column. The dark browns seen above the chlorophyls represent the tough to move waxes and such which only will flush out with methanol. Methanol is not used at all to move the cannabinoid off the column.
Now the chlorophyls are ready to come off.
Now finally the last of the waxes and gunk following chlorophyls and eluting with the use of methanol.
Here is the wrap up. Fractions collected top to bottom left to right. Larger catch jar was used to catch the waxes and methanol column flush.
The brown cannabinoid fractions will be combined and purged of solvent. Then I will proceed with molecular distillation. As a starting point removing the bulk of unwanted compounds is a breeze with a wet loaded column.