Methods to refine cannabinoids
This disclosure generally relates to gas-phase methods to simultaneously purify and decarboxylate cannabinoids in about two seconds, which are about 100-10,000 times more efficient than conventional purification and decarboxylation strategies. The methods also recover thermolabile cannabinoids such as cannabigerol at significantly higher yields than conventional methods.
1 . A method to chemically-modify a cannabinoid, comprising:
providing a composition comprising the cannabinoid, wherein the cannabinoid comprises a carboxyl group, the carboxyl group is a carboxylic acid, the cannabinoid is tetrahydrocannabinolic acid (THCA; 1-hydroxy-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromene-2-carboxylic acid), the composition comprises the cannabinoid at a concentration of at least 0.1 percent by mass, and the cannabinoid is in a liquid phase;
coating a heated surface with the composition at a surface-area-to-volume ratio of the composition that is greater than 100 per meter;
directing the composition along a heated path;
contacting the composition with sufficient energy to convert the cannabinoid into carbon dioxide and a modified cannabinoid in a gas phase, wherein the composition is contacted with the sufficient energy in the heated path, and the modified cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol);
condensing the modified cannabinoid into a condensed cannabinoid in a liquid distillate, wherein the condensed cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol); and
collecting the liquid distillate.
2 . The method of claim 1 , wherein:
the method comprises converting at least 85 percent of the cannabinoid into the condensed cannabinoid per mole;
the method is performed such that the liquid distillate comprises cannabinol at a concentration of no greater than 0.5 percent by mass; and
the method comprises producing a product from the liquid distillate, wherein the product comprises the condensed cannabinoid at a concentration of at least 60 percent by mass.
3 . The method of claim 1 , wherein the sufficient energy is at least 500 joules and no greater than 100 kilojoules per gram of the composition.
4 . The method of claim 1 , wherein the sufficient energy is no greater than 50 kilojoules per gram of the composition.
5 . The method of claim 1 , wherein the composition comprises the cannabinoid at a concentration of at least 5 percent by mass.
6 . The method of claim 1 , wherein the heated path has a length of at least 100 millimeters.
7 . The method of claim 1 , comprising contacting the modified cannabinoid with a heat sink to condense the modified cannabinoid into a condensed cannabinoid in a liquid distillate less than 240 seconds after contacting the composition with the sufficient energy.
8 . The method of claim 1 , comprising converting at least 85 percent of the cannabinoid into the condensed cannabinoid per mole.
9 . The method of claim 1 , wherein the liquid distillate comprises the condensed cannabinoid and cannabinol at a molar ratio of greater than 100:1.
10 . The method of claim 1 , wherein the liquid distillate comprises cannabinol at a concentration of no greater than 0.5 percent by mass.
11 . The method of claim 1 , comprising producing a product from the liquid distillate, wherein the product comprises the condensed cannabinoid at a concentration of at least 60 percent by mass.
12 . A method to chemically-modify a cannabinoid, comprising:
providing a composition comprising the cannabinoid, wherein the cannabinoid comprises a carboxyl group, the carboxyl group is a carboxylic acid, the cannabinoid is tetrahydrocannabinolic acid (THCA; 1-hydroxy-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromene-2-carboxylic acid), the composition comprises the cannabinoid at a concentration of at least 0.1 percent by mass, and the cannabinoid is in a liquid phase;
coating a heated surface with the composition at a surface-area-to-volume ratio of the composition that is greater than 100 per meter;
directing the composition along a heated path having a length of at least 100 millimeters;
contacting the composition with sufficient energy to convert the cannabinoid into carbon dioxide and a modified cannabinoid in a gas phase, wherein the composition is contacted with the sufficient energy in the heated path, and the modified cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol);
condensing the modified cannabinoid into a condensed cannabinoid in a liquid distillate, wherein the condensed cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol); and
collecting the liquid distillate,
wherein:
the sufficient energy is sufficient to maintain an average reaction rate for the conversion of the cannabinoid into the modified cannabinoid over a period of time;
the modified cannabinoid is condensed at an average condensation rate for the condensation of the modified cannabinoid into the condensed cannabinoid over a concurrent period of time;
the average reaction rate is no less than 50 percent of the average condensation rate;
the period of time and the concurrent period of time are chronologically identical; and
the period of time and the concurrent period of time are at least 200 milliseconds and no greater than 5 minutes.
13 . The method of claim 12 , wherein the sufficient energy is at least 500 joules and no greater than 100 kilojoules per gram of the composition.
14 . The method of claim 12 , wherein the sufficient energy is no greater than 50 kilojoules per gram of the composition.
15 . The method of claim 12 , wherein the composition comprises the cannabinoid at a concentration of at least 5 percent by mass.
16 . The method of claim 12 , comprising directing the composition along the heated path at a rate of at least 100 millimeters per minute.
17 . The method of claim 12 , comprising contacting the modified cannabinoid with a heat sink to condense the modified cannabinoid into a condensed cannabinoid in a liquid distillate less than 240 seconds after contacting the composition with the sufficient energy.
18 . The method of claim 12 , comprising converting at least 85 percent of the cannabinoid into the condensed cannabinoid per mole.
19 . The method of claim 12 , wherein the liquid distillate comprises the condensed cannabinoid and cannabinol at a molar ratio of greater than 100:1.
20 . The method of claim 12 , wherein the liquid distillate comprises cannabinol at a concentration of no greater than 0.5 percent by mass.
21 . The method of claim 12 , comprising producing a product from the liquid distillate, wherein the product comprises the condensed cannabinoid at a concentration of at least 60 percent by mass.
22 . A method to chemically-modify a cannabinoid, comprising:
providing a composition comprising the cannabinoid, wherein the cannabinoid comprises a carboxyl group, the carboxyl group is a carboxylic acid, the cannabinoid is tetrahydrocannabinolic acid (THCA; 1-hydroxy-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromene-2-carboxylic acid), the composition comprises the cannabinoid at a concentration of at least 0.1 percent by mass, and the cannabinoid is in a liquid phase;
coating a heated surface with the composition at a surface-area-to-volume ratio of the composition that is greater than 100 per meter;
directing the composition along a heated path having a length of at least 100 millimeters;
contacting the composition with sufficient energy to convert the cannabinoid into carbon dioxide and a modified cannabinoid in a gas phase, wherein the composition is contacted with the sufficient energy in the heated path, and the modified cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol);
condensing the modified cannabinoid into a condensed cannabinoid in a liquid distillate, wherein the condensed cannabinoid is tetrahydrocannabinol (THC; 6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol); and
collecting the liquid distillate,
wherein:
the method is performed such that the liquid distillate comprises the condensed cannabinoid and cannabinol at a molar ratio of greater than 100:1; and
the method comprises producing a product from the liquid distillate, wherein the product comprises the condensed cannabinoid at a concentration of at least 60 percent by mass.