Methods of purifying cannabinoids using liquid:liquid chromatography

A method of purifying one or more cannabinoids from a plant material including a plant, a plant resin or a plant extract, the method consisting essentially of the following steps:

• (a) incubating the plant material with a solvent selected from the group consisting of pentane, hexane, heptane, petroleum ethers, cyclohexane, dichloromethane, trichloromethane, tetrahydrofurane, diethyl ether, toluene, benzene, ethanol, methanol, isopropanol, acetone, acetonitrile, ethyl acetate, butane, propane, 1,1,1,2-Tetrafluoroethane (R134a), or, liquid, subcritical or supercritical CO2 or mixes thereof to form a solvent mixture which extracts the one or more cannabinoids from the plant material;
• wherein the solvent mixture has an original volume;
• (b) for THC-type extracts, adding to the solvent mixture a biphasic solvent system selected from the group consisting of hexane:ethanol:water, pentane:acetonitrile and hexane:acetonitrile, wherein the pentane:acetonitrile system and the hexane:acetonitrile system optionally include ethyl acetate and/or water as a modifier;
• for CBD-type extracts, adding to the extract a biphasic solvent system of hexane:ethanol:water;
• and for CBG-type extracts, adding to the extract a biphasic solvent system of hexane:ethanol:water;
• and
• (c) performing liquid:liquid chromatography using a biphasic solvent system of step b), thereby purifying the one or more cannabinoids.