Method for selective recovery of hydrophobic compounds
A method of selectively recovering a hydrophobic target substance. The method is applied to a solution of the target substance in a hydrophobic solvent. An insoluble polysaccharide is combined with the solution, the solution is passed over the insoluble polysaccharide or otherwise exposed to the insoluble polysaccharide. A hydrophilic solvent, which is less hydrophobic than the hydrophobic solvent, is combined with the solution or combined with the hydrophobic target substance and the insoluble polysaccharide after evaporation of the hydrophobic solvent to facilitate binding of the insoluble polysaccharide with the target substance rather than remaining in solution in the hydrophobic solvent. The cyclic polysaccharide is isolated from the solution. A dissociation solvent is combined with the cyclic polysaccharide for solubilizing the target substance from the cyclic polysaccharide and recovering the target substance.
1 . A method of selectively recovering a phytocannabinoid, the method comprising:
providing a solution comprising the phytocannabinoid in an organic solvent;
combining cyclodextrin with the solution, the cyclodextrin being insoluble in the solution;
combining a hydrophilic solvent with the solution, the hydrophilic solvent being less hydrophobic than the organic solvent for facilitating binding of the cyclodextrin with the phytocannabinoid;
isolating the cyclodextrin from the solution; and
combining a hydrophobic dissociation solvent with the cyclodextrin for solubilizing the phytocannabinoid;
wherein the cyclodextrin is added to the solution before combining the hydrophilic solvent with the solution.
2 . The method of claim 1 , wherein providing the solution comprises combining bulk plant material from Cannabis sativa with the organic solvent and separating the bulk plant material from the organic solvent.
3 . The method of claim 1 , wherein the organic solvent is selected from the group consisting of acetone, acetonitrile, tetrahydrofuran, glycerol, DMSO, dichloromethane, and chloroform.
4 . The method of claim 1 , wherein the organic solvent comprises an alcohol.
5 . The method of claim 4 , wherein the alcohol is selected from the group consisting of methanol, ethanol, n-propyl alcohol, and isopropyl alcohol.
6 . The method of claim 1 , wherein the organic solvent comprises a hydrocarbon.
7 . The method of claim 6 , wherein the hydrocarbon is selected from the group consisting of n-hexane, butane, and propane.
8 . The method of claim 1 , wherein the hydrophilic solvent comprises water.
9 . The method of claim 1 , wherein the hydrophilic solvent comprises a chelating agent.
10 . The method of claim 1 , wherein combining the hydrophilic solvent with the solution comprises evaporating at least a portion of the organic solvent prior to combining the hydrophilic solvent with the solution.
11 . The method of claim 1 , wherein the cyclodextrin is selected from the group consisting of a-cyclodextrin, β-cyclodextrin, and y-cyclodextrin.
12 . The method of claim 1 , wherein the cyclodextrin is cross-linked with hexamethylene diisocyanate.
13 . The method of claim 1 , wherein the phytocannabinoid is selected from the group consisting of CBD, CBDA, THC, THCA, and CBG.
14 . The method of claim 1 , wherein the ratio of the phytocannabinoid to the cyclodextrin in the solution after combining the hydrophilic solvent with the solution is between 1:3 and 1:10.
15 . The method of claim 1 , wherein the cyclodextrin comprises a powder that is insoluble in the solution.
16 . The method of claim 1 , wherein:
the cyclodextrin is sequestered within an immersion filter by a pore size of the immersion filter that is smaller than the cyclodextrin; and
the immersion filter is sized to receive filtrate that passes through the immersion filter.
17 . The method of claim 16 , wherein isolating the cyclodextrin from the solution comprises removing the immersion filter from the solution.
18 . The method of claim 16 , wherein combining the dissociation solvent with the cyclodextrin for recovering the phytocannabinoid comprises immersing the immersion filter in the dissociation solvent.
19 . The method of claim 1 , wherein the dissociation solvent is more hydrophobic than the organic solvent.
20 . The method of claim 19 , wherein the dissociation solvent is selected from the group consisting of methanol, ethanol, n-propyl alcohol and isopropyl alcohol, other alcohols, acetone, acetonitrile, tetrahydrofuran, glycerol, DMSO, dichloromethane, chloroform, other organic solvents, n-hexane, butane, propane, other hydrocarbons, glucose syrup, acetic acid mixed with menthol, other eutectic solvents, 1-butyl-3-methylimidazolium tetrafluoroborate, and other ionic liquids.
21 . The method of claim 1 , wherein combining the hydrophilic solvent with the solution comprises slowly adding the hydrophilic solvent to the solution to gradually decrease the solubility of the phytocannabinoid in the solution, until a target ratio of the organic solvent to the hydrophilic solvent is reached, for facilitating binding of the cyclodextrin with the phytocannabinoid.
22 . The method of claim 21 , wherein the target ratio of the organic solvent to the hydrophilic solvent is 4:6.
23 . The method of claim 21 , wherein the target ratio of the organic solvent to the hydrophilic solvent is 3:7.
24 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding a volume of the hydrophilic solvent equal to 1/20 the starting volume of the organic solvent in the solution each minute until the target ratio of the organic solvent to the hydrophilic solvent is reached.
25 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding a volume of the hydrophilic solvent equal to 2/15 the starting volume of the organic solvent in the solution each minute until the target ratio of the organic solvent to the hydrophilic solvent is reached.
26 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding a volume of the hydrophilic solvent equal to ⅙ the starting volume of the organic solvent in the solution each minute until the target ratio of the organic solvent to the hydrophilic solvent is reached.
27 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding a volume of the hydrophilic solvent equal to ⅓ the starting volume of the organic solvent in the solution each minute until the target ratio of the organic solvent to the hydrophilic solvent is reached.
28 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding a volume of the hydrophilic solvent equal to ⅔ the starting volume of the organic solvent in the solution each minute until the target ratio of the organic solvent to the hydrophilic solvent is reached.
29 . The method of claim 21 , wherein slowly adding the hydrophilic solvent to the solution comprises adding the hydrophilic solvent over a period of between 2 and 5 minutes.
30 . The method of claim 1 , wherein additional cyclodextrin is added to the solution after combining the hydrophilic solvent with the solution.