Production of cannabidiol from hemp using subcritical liquid carbon dioxide

A method for extracting cannabidiol from hemp that comprises the steps of:

• a) Providing an apparatus comprising 2 separate vessels;
• b) Milling dried hemp biomass in order to obtain a product having a bulk density of at least 0.2 g/cm3;
• c) Decarboxylating the dried biomass of step b);
• d) Filling the first vessel with the milled and decarboxylated biomass of step c);
• e) Extracting a product comprising cannabidiol, tetrahydro-cannabinol Δ9-THC and Δ8-THC and other cannabinoids from the milled and decarboxylated biomass by injecting subcritical liquid carbon dioxide at a pressure of at least 65 bars and a temperature of less than 31° C., using a mass ratio carbon dioxide to biomass of at least 10 kg CO2/kg biomass and for a period of time ranging between 30 minutes and 8 hours;
• f) Retrieving the extraction product from step e) from the first vessel and loading it onto a support selected from celite, acidic, neutral or basic alumina or silica with a mass ratio extraction product to support ranging between 1 and 20 mass %;
• g) Loading the support of step f) into the second vessel;
• h) Submitting the second vessel of step g), containing a support loaded with the extraction product, to a flow of subcritical liquid carbon dioxide at a mass ratio carbon dioxide to extraction product of at least 10 kg CO2/kg extraction product and for a period of time ranging between 30 minutes and 8 hours in order to separate cannabidiol;
• and
• i) Separating and retrieving cannabidiol.