Cannabinoid extraction process and system
Raw plant material is mixed with ethanol under pressure to extract essential elements. The resulting crude oil and ethanol with the dissolved essential elements is separated from the raw plant material and filtered to remove particulates, waxes, lipids, fats and dissolved impurities. The ethanol is then evaporated from the resulting mixture of crude oil and ethanol, and the remaining crude oil then undergoes decarboxylation and distillation to obtain the essential elements. The ethanol may be chilled before adding it to the raw plant material.
1. A process for extracting cannabinoids from raw cannabis plant material comprising the steps of:
drying raw cannabis plant material;
grinding the raw cannabis plant material to result in ground raw cannabis plant material;
adding ethanol to the ground raw cannabis plant material to form a mixture;
pressurizing the mixture;
removing solid ground raw cannabis plant material from the mixture to leave a crude oil and ethanol mixture;
filtering the crude oil and ethanol mixture to remove unwanted components;
evaporating ethanol from the filtered crude oil and ethanol mixture to leave crude oil;
decarboxylating the crude oil to leave a first residue;
subjecting the first residue to a first film wipe to remove volatile terpenes and leave a second residue;
subjecting the second residue to a second film wipe to remove non-volatile terpenes and leave a third residue; and
subjecting the third residue to a third film wipe to obtain cannabinoids.
2. The process of claim 1 , wherein the raw cannabis plant material is cannabis flower.
3. The process of claim 1 , wherein the raw cannabis plant material is cannabis leaves and stems.
4. The process of claim 1 , wherein the ethanol is at a temperature of −40° C. to −50° C. when it is added to the ground raw cannabis plant material.
5. The process of claim 4 , wherein mixture is left to soak for 5 minutes at a temperature of ≤−40° C. before the solid ground raw cannabis plant material is removed from the mixture.
6. The process of claim 1 , wherein:
the raw cannabis plant material is dried to 0-15% moisture content;
the raw cannabis plant material is ground to an average size of 250-5000 μm;
the ethanol is added to the ground raw cannabis plant material in a ratio of 1 liter of ethanol to 1 kg of ground raw cannabis plant material; and
the mixture is pressurized to pressure of 70-280 kPa.
7. The process of claim 6 , wherein the raw cannabis plant material is dried to 0-10% moisture content.
8. The process of claim 1 , wherein filtering the crude oil and ethanol mixture comprises the steps of:
adding charcoal particles to the crude oil and ethanol mixture;
agitating the charcoal particles and crude oil and ethanol mixture; and
filtering off the charcoal particles; then adding clay particles to the crude oil and ethanol mixture;
agitating the clay particles and crude oil and ethanol mixture; and
filtering off the clay particles; then adding silica particles to the crude oil and ethanol mixture;
agitating the silica particles and crude oil and ethanol mixture; and
filtering off the silica particles.
9. The process of claim 8 , wherein:
filtering off the charcoal particles comprises filtering the charcoal particles and crude oil and ethanol mixture with a 10-30 μm filter and then with an 0.25-1 μm filter;
filtering off the clay particles comprises filtering the clay and crude oil and ethanol mixture with a second 10-30 μm filter and then with a second 0.25-1 μm filter; and
filtering off the silica particles comprises filtering the silica particles and crude oil and ethanol mixture with a third 10-30 μm filter and then with a third 0.25-1 μm filter.
10. The process of claim 8 , wherein:
all the adding and agitating steps are carried out with the crude oil and ethanol mixture at a temperature of 60-78° C.; and
all the filtering off steps are carried out with the crude oil and ethanol mixture at a temperature of 10-50° C.
11. The process of claim 1 , wherein the evaporating step comprises subjecting the filtered crude oil and ethanol mixture to rotary evaporation at a temperature of 43-49° C. and a pressure of 83-101 kPa.
12. The process of claim 1 , wherein the crude oil is decarboxylated at a temperature of 120-140° C.
13. The process of claim 1 , wherein the first film wipe is performed with:
a feed temperature of 105-115° C.;
a residue discharge arm temperature of 105-115° C.;
an inner wall temperature of 155-162° C.; and
a condensing coil temperature of 58° C.
14. The process of claim 1 , wherein the second film wipe is performed with:
a feed temperature of 105-115° C.;
a residue discharge arm temperature of 105-115° C.;
an inner wall temperature of 159-162° C.; and
a condensing coil temperature of 58° C.
15. The process of claim 1 , wherein the first and second film wipes are performed at a pressure of 0.3-0.8 mbar.
16. The process of claim 1 , wherein the first film wipe is performed with an inner wall temperature of 159.5° C. and the second film wipe is performed with an inner wall temperature >159.5° C.
17. The process of claim 1 , wherein the third film wipe is performed with:
a feed temperature of 105-115° C.;
a residue discharge arm temperature of 105-115° C.;
an inner wall temperature of 168.5-170° C.; and
a condensing coil temperature of 74° C.
18. The process of claim 1 , wherein the third film wipe is performed at a pressure of 0.03-0.08 mbar.
19. The process of claim 1 , wherein the first, second and third film wipes are performed at a feed temperature of 107-110° C.
20. The process of claim 1 , wherein the raw cannabis plant material is ground to an average size of 250-300 μm.