# US 11,993,562 B2 · Methods for isolation and purification of cannabidiol (CBD) and terpenes from hemp > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,993,562 B2 - Document ID: US11993562B2 - Status: Granted - Kind: B2 - Application number: 17/657,553 - Filed: 2022-03-31 - Published: 2022-10-13 - Granted: 2024-05-28 - Earliest claimed: 2021-03-31 - Assignees: Rj Lee Group, Inc. - Applicants: RJ Lee Group, Inc. - Inventors: Alan M. Levine; Steven J. Monaco; Richard J. Lee; Duane M. Erickson - Web page: https://patentgrep.com/patent/US11993562B2 ## CPC - B01D 11/0288: {Applications, solvents} - C07C 37/50: by reactions decreasing the number of carbon atoms (C07C37/04, C07C37/045, C07C37/055, C07C37/08 take precedence) - A61K 31/658: {o-phenolic cannabinoids, e.g. cannabidiol, cannabigerolic acid, cannabichromene or tetrahydrocannabinol} - B01D 11/0284: {Multistage extraction} - B01D 11/0492: {Applications, solvents used} - B01D 15/1892: {the sorbent material moving as a whole, e.g. continuous annular chromatography, true moving beds or centrifugal chromatography} - B01D 15/1894: {Liquid-liquid chromatography, e.g. centrifugal partition chromatography or extraction chromatography} - B01D 15/325: {Reversed phase} - C07D 311/80: Dibenzopyrans; Hydrogenated dibenzopyrans - C07C 2601/16: the ring being unsaturated - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08) ## Abstract The invention provides a plurality of methods which may be employed as a single method or a plurality of sequential method steps in the isolation and purification of Cannabidiol from Hemp plants. It also provides methods for having a terpene-rich fraction as a byproduct of the method. Depending upon the ultimate objective, the individual method components may be used separately or combined with one or more method steps to accomplish the objectives. ## Claims ### Claim 1 A method of processing hemp and increasing the yield of CBD, the method comprising the steps of: heating the hemp to a temperature from about 90° C. to about 160° C. until it is dried to decarboxylate acid species comprising CBD-A and/or THC-A within the hemp to increase the yield of CBD, drying and fragmenting said hemp; subjecting said dried and fragmented hemp to water washing to remove materials that interfere with distillation and purification; and extracting CBD by placing said hemp in contact with DMSO; wherein the method is performed without ignition of the hemp. ### Claim 2 (depends on 1) The method of claim 1, further comprising the steps of: during the heating stage, separating a terpene and water vapor phase from said hemp; and condensing the terpene and water vapor phase. ### Claim 3 (depends on 2) The method of claim 2 wherein the heating is effected at 100° C. or above. ### Claim 4 (depends on 1) The method of claim 1, further comprising the step of: separating said CBD from said DMSO by employing a liquid-to-liquid extraction of DMSO against an alkane to effect extraction of said CBD from DMSO. ### Claim 5 (depends on 1) The method of claim 1, further comprising the step of: employing a C18 chromatographic separation system to remove THC. ### Claim 6 (depends on 1) The method of claim 1, further comprising the steps of: separating THC from CBD; and employing reverse phase chromatography to separate THC from CBD. ### Claim 7 A method for processing hemp to improve extraction efficiency, the method comprising the steps, performed in the following sequence, of: (a) rinsing the hemp with water; (b) rinsing the rinsed hemp with alkali, wherein the alkali is an aqueous base chosen from LiOH, NaOH, and KOH; (c) optionally, repeating the sequence of steps (a) and (b) one or more times; (d) optionally, rinsing the hemp with water; and (e) optionally, drying the hemp at elevated temperature. ### Claim 8 (depends on 7) The method of claim 7, wherein the concentration of the aqueous base is from about 0.08 N to about 0.2 N. ### Claim 9 (depends on 8) The method of claim 8, comprising the step of: (d) rinsing the hemp with water. ### Claim 10 (depends on 9) The method of claim 9, comprising the step of: (d) rinsing the hemp with water until the pH of the rinse is 8.5 or lower. ### Claim 11 (depends on 10) The method of claim 10, comprising the step of: (e) drying the hemp at elevated temperature. ### Claim 12 A method for extracting a cannabinoid-containing material from hemp for improved yield and purity, the method comprising the steps, performed in the following sequence, of: (a) rinsing the hemp with a solvent composition comprising a first solvent chosen from DMF, DMA, sulfolane, nitromethane, acetonitrile, and DMSO, and, optionally, a first hydrocarbon; (b) separating the resulting solvent composition rinse from the hemp; (c) optionally, repeating the sequence of steps (a) and (b) one or more times; (d) combining the solvent composition rinses; (e) diluting the combined solvent composition rinses with water; (f) extracting the combined solvent composition rinses with a second hydrocarbon; (g) optionally, repeating step (e) one or more times; and (h) concentrating the combined second hydrocarbon extracts via evaporation, thereby obtaining the cannabinoid-containing material. ### Claim 13 (depends on 12) The method of claim 12, wherein the second hydrocarbon is the same as the first hydrocarbon. ### Claim 14 (depends on 13) The method of claim 13, wherein the first hydrocarbon is an aliphatic hydrocarbon. ### Claim 15 (depends on 12) The method of claim 12, wherein the first solvent is DMSO. ### Claim 16 (depends on 15) The method of claim 15, wherein the (v/v) ratio of the first solvent rinses/water at step (e) is from about 1/2 to about 2/1. ### Claim 17 (depends on 15) The method of claim 15, wherein the (v/v) ratio of first solvent/first hydrocarbon at step (a) is from about 1/2 to about 2/1. ### Claim 18 (depends on 12) The method of claim 12, further comprising the step of purifying the cannabinoid-containing material. ### Claim 19 (depends on 18) The method of claim 18, wherein the purification is accomplished with reverse-phase chromatography. ### Claim 20 (depends on 18) The method of claim 18, wherein the purification is accomplished with centrifugal partition chromatography (CPC). ### Claim 21 (depends on 1) The method of claim 1, with the proviso that the method does not include a winterization step.