U.S. patent application number 15/959843 was filed with the patent office on 2018-08-23 for cannabidiol extraction and conversion process.
The applicant listed for this patent is CLS Labs, Inc.. Invention is credited to Raymond M. Keller.
Application Number | 20180237368 15/959843 |
Document ID | / |
Family ID | 61952328 |
Filed Date | 2018-08-23 |
United States Patent
Application |
20180237368 |
Kind Code |
A1 |
Keller; Raymond M. |
August 23, 2018 |
CANNABIDIOL EXTRACTION AND CONVERSION PROCESS
Abstract
A cannabidiol extraction and conversion process includes an
extraction process including a sizing unit wherein raw Cannabis
plant material is reduced to a uniform size, a blending unit
wherein an extraction solvent is blended together with the Cannabis
plant material to form an initial extract, and a primary solvent
exchange rotary evaporator unit wherein an exchange solvent is
added to the initial extract, and a processed extract rich in
cannabidiol is obtained. A conversion process includes a conversion
rotary reflux unit wherein the processed extract is combined and
processed with an acidic component, a separator unit wherein a
solvent is added and a separator organic effluent is obtained, a
secondary solvent exchange rotary evaporator unit wherein a further
solvent is added, and a fractionation unit wherein the
tetrahydrocannabinol obtained is separated into a plurality of
functional fractions for selective blending.
Inventors: |
Keller; Raymond M.; (Naples,
FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CLS Labs, Inc. |
Miami |
FL |
US |
|
|
Family ID: |
61952328 |
Appl. No.: |
15/959843 |
Filed: |
April 23, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14923617 |
Oct 27, 2015 |
9950976 |
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15959843 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01D 11/028 20130101;
B01D 12/00 20130101; B01D 11/0284 20130101; B01D 11/0476 20130101;
C07C 37/004 20130101; B01D 11/0273 20130101; B01D 11/0296 20130101;
C07C 2601/16 20170501; B01D 11/0226 20130101; B01D 11/0446
20130101; C07C 37/004 20130101; C07C 39/23 20130101 |
International
Class: |
C07C 37/00 20060101
C07C037/00; B01D 11/02 20060101 B01D011/02 |
Claims
1. A cannabidiol extraction process including: sizing an amount of
raw Cannabis plant material, blending an amount of dichloromethane
with the amount of Cannabis plant material to form an initial
extract, removing dichloromethane from the initial extract in a
primary solvent exchange rotary evaporator unit, adding an amount
of ethanol to the initial extract remaining in the primary solvent
exchange rotary evaporator unit after at least partially removing
dichloromethane, thereby producing an evaporated extract comprising
cannabidiol in ethanol and dichloromethane.
2. The cannabidiol extraction process as recited in claim 1 wherein
the amount of raw Cannabis plant material is about 115 kilograms
per day.
3. The cannabidiol extraction process as recited in claim 2 wherein
dichloromethane is added to the raw Cannabis plant material in the
blending unit in an amount of about three to four kilograms of
dichloromethane per kilogram of raw Cannabis plant material.
4. The cannabidiol extraction process as recited in claim 1 further
comprising filtering the initial extract in a primary filtration
unit.
5. The cannabidiol extraction process as recited in claim 1 further
comprising contacting the initial extract with activated carbon in
an extraction adsorption unit.
6. The cannabidiol extraction process as recited in claim 1 further
comprising processing the evaporated extract through a wax
coalescing unit to coalesce waxes and fats present in the
evaporated extract.
7. The cannabidiol extraction process as recited in claim 6 further
comprising filtering the evaporated extract, after processing the
evaporated extract through the wax coalescing unit, through a
secondary filtration unit to remove coalesced waxes and fats to
produce a processed extract.
8. The cannabidiol extraction process as recited in claim 7 wherein
the processed extract comprises cannabidiol in ethanol and
dichloromethane.
9. The cannabidiol extraction process as recited in claim 8 wherein
the processed extract comprises cannabidiol in a range of about
sixty percent to about eighty percent by weight.
10. A cannabidiol conversion process for a processed extract
comprising cannabidiol in ethanol and dichloromethane, comprising:
mixing an amount of concentrated sulfuric acid with an amount of
the processed extract in a conversion rotary reflux unit and
refluxing therein to obtain a conversion reflux, combining an
amount of dichloromethane with the conversion reflux in a separator
unit, removing a solvent layer consisting primarily of
dichloromethane and ethanol from the separator unit and leaving a
separator organic effluent remaining therein, combining the
separator organic effluent with an amount of ethanol in a secondary
solvent exchange rotary evaporator unit wherein dichloromethane and
ethanol are at least partially evaporated off to produce an
exchange reflux which comprises tetrahydrocannabinol in ethanol and
dichloromethane.
11. The cannabidiol conversion process as recited in claim 10
wherein the concentrated sulfuric acid has a concentration of about
95 percent to about 98 percent.
12. The cannabidiol conversion process as recited in claim 11
wherein the amount of concentrated sulfuric acid added to the
processed extract is in a range of about two percent to three
percent by weight of the amount of processed extract.
13. The cannabidiol conversion process as recited in claim 10
wherein the dichloromethane has a purity of about ninety-five
percent.
14. The cannabidiol conversion process as recited in claim 13
wherein the dichloromethane is added to the conversion reflux in an
amount of about one kilogram of dichloromethane per kilogram of the
conversion reflux.
15. The cannabidiol conversion process as recited in claim 10
further comprising contacting the separator organic effluent
obtained from the separator unit with activated carbon in a
conversion adsorption unit prior to combining the separator organic
effluent with ethanol in the secondary solvent exchange rotary
evaporator unit.
16. The cannanidiol conversion process as recited in claim 10
further comprising separating the exchange reflux into a plurality
of cannabinoid fractions in a fractionation unit.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention is directed to a process for the
extraction of cannabidiol from any of a variety of plants of the
genus Cannabis, including but not limited to industrial hemp
varieties which have been specifically bred to substantially limit
the amount of the psychoactive cannabinoid, tetrahydrocannabinol,
produced therein. The present invention is further directed to a
procedure for the conversion of cannabidiol, such as may be
extracted in commercially viable amounts from industrial hemp, to
tetrahydrocannabinol.
Description of the Related Art
[0002] Various attempts have been made to extract
tetrahydrocannabinol and other cannabinoid constituents present in
industrial hemp in order to isolate the psychoactive cannabinoid
fractions therein. At least two of the known processes require
operation under supercritical conditions which, in addition to
being extremely expensive to construct and operate on a commercial
scale, are complicated and considerably more dangerous to operate
than processes operating closer to ambient conditions. Butane and
carbon dioxide are known to have been utilized as extraction
"fluids" in such supercritical processes.
[0003] A further disadvantage of butane as a supercritical
extraction "fluid" lies in the fact that commercial grade butane
includes amounts of mercaptan to provide for odor detection, as
pure butane is odorless. As such, extracts obtained via this
supercritical butane extraction process also comprise unwanted
amounts of mercaptan as well.
[0004] Another process utilizes ethanol as an extraction fluid,
however, less than pure ethanol is often utilized, i.e., denatured
ethanol, thereby allowing harmful contaminants in the denatured
ethanol to pass though to the extracted cannabinoid
constituents.
[0005] One crude conversion process is known to exist which begins
with an oily feedstock rich in .DELTA.8-tetrahydrocannabinolic acid
("THCA") and isomers thereof. The THCA is spread onto parchment
paper or a similar substrate, and is exposed to extreme heat, such
as may be provided by industrial heaters, resulting in
decarboxylation and formation of the psychoactive cannabinoid
fraction, tetrahydrocannabinol. As will be appreciated, such a
process is inefficient and difficult to control, thus resulting in
end products having widely varying amounts of conversion product,
i.e., tetrahydrocannabinol.
[0006] As such, it would be beneficial to provide a safe and
economical process for the extraction of cannabinoid components
from industrial hemp. It would be further advantageous to have a
conversion process wherein an extraction component rich in
cannabidiol is converted into a conversion product rich in
tetrahydrocannabinol. A further benefit may be realized by
providing a process for fractionation of a conversion product into
a plurality of cannabinoid classes which may subsequently be
recombined in predetermined amounts in order to mimic the
cannabinoid profile in well known, but difficult and/or expensive
to cultivate strains of Cannabis plants.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to a cannabidiol
extraction and conversion process. In at least one embodiment, a
cannabidiol extraction process includes a sizing unit wherein an
amount of raw Cannabis plant material is reduced to a uniform size
in order to maximize the extraction efficiency therefrom upon
contact with one or more extraction solvents.
[0008] A blending unit is provided in at least one embodiment of a
cannabidiol extraction process in accordance with the present
invention wherein a first solvent is blended together with the
Cannabis plant material to form an initial extract. A primary
filtration unit and/or an extraction adsorption unit are
incorporating into at least one embodiment of a conversion process
in order to remove unwanted plant matter and/or other unwanted
extraction byproducts from the initial extract.
[0009] In accordance with one further embodiment of a cannabidiol
extraction process in accordance with the present invention, a
primary solvent exchange rotary evaporator unit wherein the initial
extract is processed further with a second solvent, thereby forming
a processed extract.
[0010] As noted above, the present invention further comprises a
cannabidiol conversion process. In at least one embodiment, a
cannabidiol conversion process comprises a conversion rotary reflux
unit wherein a processed extract is processed with an acidic
component to form a conversion reflux. A separator unit is provided
in one embodiment to remove solvent from the conversion reflux and
produce a separator organic effluent. A secondary solvent exchange
rotary evaporator unit is employed in at least one embodiment to
exchange remaining solvent from the separator organic effluent,
resulting in an exchange reflux.
[0011] In at least one embodiment, a fractionation unit is employed
to separate the exchange reflux into a plurality of cannabinoid
classes or fractions, which may be subsequently recombined in
predetermined amounts in order to mimic the cannabinoid profile in
well known, but difficult and/or expensive to cultivate strains of
Cannabis plants.
[0012] These and other objects, features and advantages of the
present invention will become clearer when the drawings as well as
the detailed description are taken into consideration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a fuller understanding of the nature of the present
invention, reference should be had to the following detailed
description taken in connection with the accompanying drawings in
which:
[0014] FIGS. 1A and 1B present a diagrammatic representation of one
illustrative embodiment of an extraction process of a cannabidiol
extraction and conversion process in accordance with the present
invention.
[0015] FIGS. 2A and 2B present a diagrammatic representation of one
illustrative embodiment of a conversion process of a cannabidiol
extraction and conversion process in accordance with the present
invention.
[0016] Like reference numerals refer to like parts throughout the
several views of the drawings.
DETAILED DESCRIPTION
[0017] The present invention is directed to a cannabidiol
extraction and conversion process, as stated above. More in
particular, in at least one embodiment of the present invention,
cannabidiol is extracted from a plant of the genus Cannabis. In yet
one further embodiment, the plant of the genus Cannabis comprises
industrial hemp which has been specifically bred to substantially
limit the amount of the psychoactive cannabinoid,
tetrahydrocannabinol, produced therein, in favor of the
non-psychoactive cannabinoid, cannabidiol.
[0018] In at least one embodiment, the raw Cannabis plant material
is dried to minimize the amount of water present therein which may
reduce the efficiency of the extraction process. The stems, stalks,
and roots of the Cannabis plant are cut or chopped into small
pieces prior to placement into an extraction vessel. The flowers,
buds, and leaves of the Cannabis plant, in general, do not require
any size reduction prior to the extraction process. In at least one
embodiment, the stems, stalks, and roots of the Cannabis plant are
cut or chopped into pieces having a maximum dimension of about
one-quarter inch to about one-half inch. In one further embodiment,
the raw Cannabis plant material is dried after being cut or chopped
into small pieces, so as to facilitate the drying process.
[0019] The sized Cannabis plant material which, as used herein,
includes the stems, stalks, and roots of the Cannabis plant which
have been cut or chopped into pieces along with any flowers, buds,
or leaves present, is placed into an extraction vessel and is
substantially covered with a solvent. In one embodiment, the
solvent comprises dichloromethane, i.e., CH.sub.2Cl.sub.2, and in
at least one embodiment, the dichloromethane has a purity of about
95 percent.
[0020] The mixture of sized Cannabis plant material and
dichloromethane is shaken or stirred during an initial extraction
cycle until the solvent takes on color from the Cannabis plant
material. Once the solvent has taken on color from the Cannabis
plant material, the extraction solution is drained from the
extraction vessel. The extraction cycle is repeated with fresh
dichloromethane being used for each additional extraction cycle. In
at least one embodiment, two additional extraction cycles are
performed. The extraction solutions recovered from the extraction
vessel from each of the extraction cycles are combined into a
single vessel, and the remaining solid Cannabis plant material may
be discarded.
[0021] The combined extraction solution is processed through
activated carbon to adsorb solids and other unwanted components
from the combined extraction solution. In at least one embodiment,
granular activated carbon having an average size of about 35 to 40
micron, i.e., U.S. Mesh 400, is utilized. A contact time of the
combined extraction solution with the granular activated carbon of
about 20 to 45 minutes is utilized in accordance with one
embodiment of the present invention.
[0022] After processing through activated carbon, in accordance
with at least one embodiment of the present invention, an amount of
combined extraction solution of about 20 to 50 liters is placed
into a 100 liter rotary evaporator to remove excess
dichloromethane. As will be appreciated by those of skill in the
art, the volume of extraction solution and the volume of the
evaporator can be scaled up, as needed, for large capacity
production, such as is disclosed in Example 1 below with reference
to the figures herein.
[0023] In at least one embodiment, the rotary evaporator operates
under a slight vacuum in the range of about 400 to 600 millimeters
of mercury ("mm HG"). In one further embodiment, the combined
extraction solution in the rotary evaporator is maintained at a
temperature in a range of about 40 to 50 degrees Celsius (".degree.
C."), and in yet one further embodiment, the rotary evaporator is
maintained at a temperature of about 43.degree. C. The rotary
evaporator, in accordance with one embodiment of the present
invention, is operated at a speed in a range of about 100 to 200
revolutions per minute ("rpm").
[0024] During the rotary evaporation process, dichloromethane is
removed and a concentrated extract remains. An amount of ethanol,
i.e., C.sub.2H.sub.5OH, is added to the concentrated extract in the
rotary evaporator. In one embodiment, the ethanol has a purity of
about 100%. The ethanol and concentrated extract are allowed to
blend together in the rotary evaporator at a speed of about 100 to
200 rpm, until a homogenous solution is obtained. In at least one
embodiment, the amount of ethanol added is equal to about three
times the amount of the concentrated extract remaining in the
rotary evaporator following the rotary evaporation process.
[0025] Following the blending process, the ethanol extract is
defatted via a wax coalescing process, and in one further
embodiment, a filter is utilized to collect and remove coalesced
fat from the ethanol extract, leaving a processed extract
comprising cannabidiol in a range of about 60% to 80% by
weight.
[0026] As noted above, the present invention further comprises a
process for the conversion of cannabidiol to tetrahydrocannabinol.
To begin, in at least one embodiment, an amount of defatted extract
comprising cannabidiol in a range of about 60% to 80% by weight is
placed into a reflux reaction vessel. One drop of concentrated
sulfuric acid, i.e., 95% to 98% sulfuric acid, is added to the
reflux reaction vessel per gram of defatted extract. The reflux
reaction is carried out under a vacuum in a range of about 400 to
600 mm HG at a temperature in arrange of about 80.degree. C., for a
time of about 2 hours.
[0027] The refluxed extract is placed into a separator with water
and dichloromethane. In at least one embodiment, the amount of
water added to the separator is about twice the amount of the
refluxed extract, and the amount of dichloromethane added is about
equal to the amount of the refluxed extract.
[0028] The separator is shaken to thoroughly mix the aqueous and
organic fractions, and the resulting mixture is allowed to stand
for about 30 minutes to separate into layers. In at least one
embodiment, the separator is vented to atmosphere. The aqueous
layer is decanted from the separator and discarded.
[0029] The remaining organic extract is then rinsed in the
separator with an amount of water equal to about twice the volume
of the organic extract remaining, and an amount of one normal
sodium hydroxide solution, i.e., 1N NaOH, is added. In at least one
embodiment, the amount of 1N NaOH solution added is equal to the
amount of concentrated sulfuric acid added during the extraction
process. This mixture is agitated and the pH tested. Additional
amounts of the 1N NaOH are added under agitation until the pH of
the solution is about neutral, i.e., a pH of about 7.
[0030] Once the pH has been adjusted to about neutral, the solution
is agitated further, vented, and is allowed to separate. The
aqueous layer is once again decanted and discarded, and the
remaining organic layer is rinsed with water in accordance with the
foregoing procedure two additional times.
[0031] The rinsed organic extract is filtered through activated
carbon to remove residual water. In at least one embodiment, the
carbon filtration is performed under vacuum.
[0032] After carbon filtration, the organic extract is filtered to
about 2 microns and is once again transferred into a rotary
evaporator to remove dichloromethane. In at least one embodiment,
an amount of ethanol is added to the oily extract in a ratio of
about three parts ethanol to one part of oily extract.
[0033] A final step, in at least one embodiment, is to dry the
ethanol/oil mixture in the rotary evaporator to remove any
dichloromethane which remains entrapped therein, and the finished
product is packaged for further use.
[0034] In accordance with at least one embodiment of the present
invention, a defatted extract comprising cannabidiol in a range of
about 60% to 80% by weight is converted into an ethanol/oil mixture
comprising tetrahydrocannabinol in a range of about 60% to 80% by
weight.
Example I: Extraction Process
[0035] As stated above, the present invention is directed to a
cannabidiol extraction and conversion process generally as shown as
at 10 throughout the figures. More in particular, FIGS. 1A and 1B
present one illustrative embodiment of a cannabidiol extraction
process 100, while FIGS. 2A and 2B present one illustrative
embodiment of a cannabidiol conversion process 200.
[0036] Turning first to the illustrative embodiment of a
cannabidiol extraction process 100 as shown in FIGS. 1A and 1B, the
process begins with an amount of raw materials, namely, raw
Cannabis plant material 20. As before, in at least one embodiment,
the raw Cannabis plant material 20 utilized in accordance with the
present invention comprises industrial hemp varieties specifically
bred to substantially limit the amount of tetrahydrocannabinol
produced therein.
[0037] The extraction process further comprises at least one
extraction solvent. In at least one embodiment, such as shown in
FIG. 1A, an extraction process 100 in accordance with the present
invention comprises a plurality of extraction solvents, namely,
extraction solvent A 30 and extraction solvent B 40. In accordance
with at least one embodiment of the present invention, extraction
solvent A 30 comprises dichloromethane, i.e., CH.sub.4Cl.sub.2. In
one further embodiment of an extraction process 100 in accordance
with the present invention extraction solvent B 40 comprises
ethanol, i.e., C.sub.2H.sub.5OH.
[0038] Looking further to the illustrative embodiment of FIG. 1A,
the extraction process 100 comprises a sizing unit 110 which is
utilized to cut, chop, etc., the raw Cannabis plant material 20
into an appropriate size for extraction of cannabidiol therefrom.
In at least one embodiment, a sizing unit 110 reduces the raw
Cannabis plant material 20 to pieces having a uniform maximum
dimension of about one-quarter inch to one-half inch.
[0039] Following the sizing unit 110, the sized Cannabis plant
material 20 is transferred to a blending unit 120. It is in
blending unit 120 that the primary extraction occurs, and as such,
amounts of extraction solvent A 30 and/or amounts of extraction
solvent B 40 are introduced into blending unit 120 with a
corresponding amount of sized Cannabis plant material 20. In at
least one embodiment, the blending process utilizes solvent A 30
comprising dichloromethane, and is carried out at ambient
temperature and pressure for a period of about 20 minutes, per
batch, at a speed of about 30 rpm. In one further embodiment,
solvent A 30 comprises dichloromethane having a purity of about 95
percent.
[0040] As further shown in the illustrative embodiment of FIG. 1A,
following the primary extraction process in the blending unit 120,
solid plant material is discharged, and may be discarded, and an
initial extract 50 is retained for further processing.
[0041] Turning next to FIG. 1B, the initial extract 50 from
blending unit 120 is directed through a primary filtration unit
130. As will be appreciated by those with skill in the art, primary
filtration unit 130 may include an appropriately sized bag or
screen type filter so as to remove any solid particulate plant
material remaining in the initial extract 50. In at least one
embodiment, primary filtration unit 130 further comprises a bag
filter press for collection and removal of solid particulate matter
from the initial extract 50.
[0042] With further reference to the illustrative embodiment of
FIG. 1B, the present extraction process 100 further comprises an
extraction adsorption unit 140. In at least one embodiment, an
extraction adsorption unit 140 comprises an amount of an
appropriately sized granular activated carbon material which is
selected to remove specific unwanted components from initial
extract 50. A contact time of about 20 to 30 minutes for the
initial extract 50 in the extraction adsorption unit 140 is
utilized in at least one embodiment of the present invention.
[0043] Following the extraction adsorption unit 140, the initial
extract 50 is introduced into a primary solvent exchange rotary
evaporator unit 150. As shown in the illustrative embodiment of
FIG. 1B, an amount of solvent B 40 is also fed into the primary
solvent exchange rotary evaporator unit 150. Once again, in at
least one embodiment of the present extraction process 100, solvent
B 40 comprises ethanol having a purity of about 100%. In one
further embodiment, the amount of solvent B 40 comprising 100%
ethanol added to the primary solvent exchange rotary evaporator
unit 150 is about equal to the amount of initial extract 50 added
thereto.
[0044] The primary solvent exchange rotary evaporator unit 150 in
accordance with at least one embodiment of the present invention is
operated at a temperature of about 40 to 60.degree. C. under a
vacuum of about 400 to 600 mm Hg. In accordance with at least one
further embodiment, the primary solvent exchange rotary evaporator
unit 150 operates at a speed in a range of about 100 to 200 rpm. In
yet one further embodiment, the initial extract 50 is processed in
the primary solvent exchange rotary evaporator unit 150 with
solvent B 40 for a period of time in a range of about 2 to 3
hours.
[0045] An evaporated extract 52 is obtained from the primary
solvent exchange rotary evaporator unit 150. Further, an amount of
solvent A 30 may be recovered via a condenser unit and recycled to
the solvent A 30 storage tank. The resultant evaporated extract 52
is relatively high in fatty content and as such, in at least one
embodiment, the evaporated extract 52 is processed through a wax
coalescing unit 160 so as to "defat" the evaporated extract 52.
[0046] In one further embodiment, a secondary extraction filtration
unit 170 is employed following a wax coalescing unit 160 to collect
waxes and/or fats which drop from solution in the wax coalescing
unit 160, thereby resulting in an end product of one embodiment of
the extraction process 100 in accordance with the present
invention, namely, a processed extract 54. As will be appreciated
by those of skill in the art, processed extract 54 will be
relatively high in cannabidiol content. More in particular, a
processed extract 54 obtained via an extraction process 100 in
accordance with at least one embodiment of the present invention
will comprise cannabidiol in amounts in a range of about 60% to 80%
by weight.
Example II: Conversion Process
[0047] Turning next to the illustrative embodiment presented in
FIGS. 2A and 2B, a conversion process 200 in accordance with the
present cannabidiol extraction and conversion process 10 is
presented. As shown in the illustrative embodiment of FIG. 2A, a
processed extract 54, such as may be obtained from extraction
process 100 in accordance with the present invention, is a primary
feedstock to a conversion process 200. More in particular, a
processed extract 54 is introduced into a conversion rotary reflux
unit 210 along with the amount of acidic component 62. More in
particular, in at least one embodiment, acidic component 62
comprises sulfuric acid, and in one further embodiment, acidic
component 62 comprises concentrated sulfuric acid, i.e., sulfuric
acid at a concentration of about 95% to 98%. The acidic component
62 comprising concentrated sulfuric acid is added to a conversion
rotary reflux unit 210 in an amount in a range of about 2% to 3% of
the weight of the processed extract 54, in accordance with at least
one embodiment of the present conversion process 200.
[0048] A conversion rotary reflux unit 210 in one embodiment is
operated at a temperature of about 40 to 60.degree. C., and under a
vacuum in a range of about 400 to 600 mm Hg. In accordance with at
least one embodiment, the conversion rotary reflux unit 210
operates at a speed of about 100 to 200 rpm. In yet one further
embodiment, the processed extract 54 is processed in the conversion
rotary reflux unit 210 for a period of about 2 to 3 hours.
[0049] Following the conversion rotary reflux unit 210, a
conversion reflux 70 is introduced into a separator unit 220. As
shown in the illustrative embodiment of FIG. 2A, an amount of
extraction solvent A 30 is introduced into separator unit 220 with
the conversion reflux 70. As before, in at least one embodiment,
solvent A 30 comprises dichloromethane, and in one further
embodiment, solvent A 30 comprises dichloromethane having a purity
of about 95 percent. In addition, in accordance with one embodiment
of the present conversion process 200, amounts of deionized water
60 and a basic component 64 are also added to separator unit 220
with the conversion reflux 70 and solvent A 30.
[0050] In accordance with one embodiment of the present conversion
process 200, the amount of solvent A 30 added to the separator unit
220 is about equal to the volume of conversion reflux 70 added
thereto, and the amount of deionized water 60 added to the
separator unit 220 is equal to about two times the volume of
conversion reflux 70. The basic component 64 comprises 1N NaOH in
at least one embodiment, and is added in amounts sufficient to
adjust the pH of the mixture of the conversion reflux 70, solvent A
30, and deionized water 60 in separator unit 220 to approximately
neutral. Separator unit 220 operates at ambient temperature and
pressure in accordance with at least one embodiment of the present
conversion process 200.
[0051] As shown in the illustrative embodiment of FIG. 2A, a
separator organic effluent 72 is obtained from separator unit 220.
Further, a solvent layer 73, consisting primarily of solvent A 30
and/or solvent B 40 from separator unit 220, is directed to a
solvent distillation unit 225 for separation and return to the
respective solvent storage tanks for use in the extraction process
100.
[0052] Turning next to the illustrative embodiment of FIG. 2B, the
separator organic effluent 72 is initially processed through a
conversion adsorption unit 240. As with extraction adsorption unit
140, in at least one embodiment, a conversion adsorption unit 240
in accordance with the present invention comprises an amount of
granular activated carbon to remove select unwanted components from
the separator organic effluent 72. In at least one embodiment, a
U.S. mesh 400 activated carbon in utilized in conversion adsorption
unit 240. A contact time of about 20 to 45 minutes is provided for
the separator organic effluent 72 in the conversion adsorption unit
240 in accordance with at least one embodiment of the present
invention, and in at least one further embodiment, a contact time
of about 30 to 45 minutes is provided.
[0053] Following the conversion adsorption unit 240, the separator
organic effluent 72 is introduced into a secondary solvent exchange
rotary evaporator unit 250. As further shown in the illustrative
embodiment of FIG. 2B, an amount of solvent B 40 is also introduced
into the secondary solvent exchange rotary evaporator unit 250.
Solvent B 40 in at least one embodiment, as before, comprises
ethanol, and in one further embodiment, solvent B 40 comprises
ethanol having a concentration of about 100%. The amount of solvent
B 40 added to secondary solvent exchange rotary evaporator unit
250, in one embodiment, is in a range of about one-half the volume
of separator organic effluent 72 to about twice the volume of
separator organic effluent 72. In at least one further embodiment,
the amount of solvent B 40 added to the secondary solvent exchange
rotary evaporator unit 250 is about equal to the volume of
separator organic effluent 72.
[0054] In accordance with at least one embodiment of the present
conversion process 200, a secondary solvent exchange rotary
evaporator unit 250 is operated at a temperature of about 40 to
60.degree. C., and under a vacuum in a range of about 400 to 600 mm
Hg. In accordance with one further embodiment, a secondary solvent
exchange rotary evaporator unit 250 is operated at a speed of about
100 to 200 rpm. In yet one further embodiment, the separator
organic effluent 72 is processed in the secondary solvent exchange
rotary evaporator unit 250 with solvent B 40 for a period of time
in a range of about 1 to 4 hours, and in one further embodiment,
the separator organic effluent 72 is processed in the secondary
solvent exchange rotary evaporator unit 250 for about 2 hours.
[0055] After processing via the secondary solvent exchange rotary
evaporator unit 250, an exchange reflux 74 is obtained from the
secondary solvent exchange rotary evaporator unit 250. In
accordance with at least one embodiment of the present invention,
an exchange reflux 74 comprises about 60% to 80%
tetrahydrocannabinol by weight.
[0056] Similar to primary solvent exchange rotary evaporator unit
150, in at least one embodiment of the present invention, a
condenser is employed in combination with the secondary solvent
exchange rotary evaporator unit 250 in order to recover an amount
of solvent A 30 for return to solvent A 30 storage tank for further
use in an extraction process 100 in accordance with the present
invention.
[0057] The final step in accordance with at least one embodiment of
a conversion process 200 of the present invention comprises
processing an exchange reflux 74 through a fractionation unit 260.
In at least one embodiment, the fractionation unit 260 separates
the exchange reflux 74 into a plurality of functional fractions or
classes which collectively define a conversion product 90. In
accordance with at least one embodiment, the fractionation unit 260
separates the exchange reflux 74 into eight functional fractions or
classes, namely, a cannabinol ("CBN") fraction 91, a
tetrahydrocannabinol ("THC") fraction 92, a cannabigerol ("CBG")
fraction 93, a cannabidiol ("CBD") fraction 94, a cannabichromene
("CBC") fraction 95, a cannabichromanone ("CBCN") fraction 96, a
cannabifuran ("CBF") fraction 97, and a cannabielsoin ("CBE")
fraction 98.
[0058] As such, the conversion product 90 in accordance with the
present invention comprises functional fractions which may be
selectively recombined, such as, by way of example, via blending
either alone or in combination with inert carrier agents, in a
manner that replicates the overall cannabinoid profile in various
strains of specially grown Cannabis plants, and in at least one
embodiment, to replicate the overall tetrahydrocannabinol profile
of Cannabis plants exhibiting the greatest psychoactive
properties.
[0059] Further, the conversion product 90 in accordance with the
present invention comprises tetrahydrocannabinol which may
administered via any of a number of delivery mechanisms including,
at least, personal electronic vaporizing devices, more commonly
known as e-cigarettes.
[0060] With reference once again to the illustrative embodiment of
FIGS. 2A and 2B, and in accordance with at least one alternative
embodiment of the present invention, a processed extract 54'
obtained from extraction process 100 is processed directly via
fractionation unit 260, bypassing the conversion rotary reflux unit
210, separator unit 220, conversion adsorption unit 240, and
secondary solvent exchange unit 250. In this alternative
embodiment, the fractionation unit 260 again separates the
tetrahydrocannabinol and other target analytes present in the
processed extract 54', albeit in lesser amounts than in exchange
reflux 74, into a plurality of functional fractions which, once
again, collectively define a conversion product 90. As before, the
fractionation unit 260 separates the processed extract 54' into
eight functional fractions, namely, a cannabinol ("CBN") fraction
91, a tetrahydrocannabinol ("THC") fraction 92, a cannabigerol
("CBG") fraction 93, a cannabidiol ("CBD") fraction 94, a
cannabichromene ("CBC") fraction 95, a cannabichromanone ("CBCN")
fraction 96, a cannabifuran ("CBF") fraction 97, and a
cannabielsoin ("CBE") fraction 98.
[0061] Also as before, the conversion product 90 in accordance with
this alternative embodiment of the present invention comprises
functional fractions which may be selectively recombined in a
manner that replicates the overall cannabinoid profile in various
strains of specially grown Cannabis plants.
[0062] Of course, it will be appreciated by those of skill in the
art that the foregoing extraction process 100 and conversion
process 200 may be readily scaled up or down in order to increase
and/or decrease throughput such as conditions may require. In at
least one embodiment, the present cannabidiol extraction and
conversion process 10 is sized to accommodate a feedstock input of
about 115 kilograms, or approximately 250 pounds, of raw Cannabis
plant material 20 per eight hour shift, which will produce an
amount of about 35 to 45 kilograms of conversion product 90 which,
once again, comprises about 60% to 80% tetrahydrocannabinol by
weight.
[0063] Since many modifications, variations and changes in detail
can be made to the described embodiment of the invention, it is
intended that all matters in the foregoing description and shown in
the accompanying drawings be interpreted as illustrative and not in
a limiting sense. Thus, the scope of the invention should be
determined by the appended claims and their legal equivalents.
* * * * *