Patent Application
20230034720
This invention relates generally to systems and methods for extracting cannabidiol (CBD) from cannabis, and particularly to systems and methods that utilize a crude oil to separate water, fats, and proteins prior to preparation of a CBD distillate.
At present, the most efficient methods for extracting cannabidiol (CBD) from cannabis plants are solvent extraction processes, in which the cannabis biomass is contacted with a liquid solvent. Ethanol is widely considered the most effective solvent for such processes and is by far the most commonly used. However, pure (99% purity or higher) ethanol is very expensive and tightly regulated by many governments, and is thus extremely difficult to obtain in quantities sufficient for industrial-scale applications (3,000 to 5,000 gallons). As a result, most skilled artisans use a mixture of ethanol and water, typically comprising 5% to 8% water, as the solvent in CBD solvent extraction processes.
The presence of water in CBD extraction solvents presents several drawbacks. Most significantly, when cannabis biomass is contacted with an aqueous solvent, fats and hydrophilic proteins in the cannabis biomass are solubilized in the water. When the solvent is subsequently heated, as most separation processes require, the proteins in the solvent solidify, thus fouling process equipment and requiring frequent shutdown and cleaning of the extraction system.
There is thus a need in the art for systems and methods for extracting CBD from cannabis that avoid or prevent fouling and clogging of the process equipment by proteins and other impurities present in the solvent after extraction. It is further advantageous for such systems and methods to be compatible with currently known, inexpensive, and/or widely available solvents, e.g., ethanol/water mixtures.
It is one aspect of the present invention to provide a method for separating a first organic substance from a second organic substance in an aqueous solution or suspension, comprising (a) providing the aqueous solution or suspension, the aqueous solution or suspension comprising the first and second organic substances; (b) forming a first phase and a second phase from the aqueous solution or suspension by at least one of (i) contacting the aqueous solution or suspension with at least one of a liquid separating agent and a solid separating agent, and (ii) at least one of centrifugation, filtration, and sedimentation of the aqueous solution or suspension; and (c) removing one of the first phase and the second phase to a vessel, wherein the first organic substance comprises at least one of a cannabinoid and a terpene, wherein the second organic substance comprises at least one of a protein and a lipid, wherein the first phase comprises at least most of the first organic substance present in the aqueous solution or suspension, wherein the second phase comprises at least most of the second organic substance present in the aqueous solution or suspension, and wherein the first and second phases are substantially immiscible.
In embodiments, the first organic substance may comprise a cannabinoid. The cannabinoid may, but need not, be cannabidiol.
In embodiments, the aqueous solution or suspension may originate from an ethanol extraction process for extraction of the first organic substance from cannabis plant material. The method may, but need not, further comprise obtaining a solid fraction of the second phase by at least one of drying the second phase and filtering the second phase; and recycling the solid fraction of the second phase to the ethanol extraction process.
In embodiments, the method may further comprise providing the first phase to a distillation process for producing a distillate of the first organic substance.
In embodiments, the first phase may comprise at least about 75% of the first organic substance present in the aqueous solution or suspension.
In embodiments, at least one step may be carried out at a temperature of no less than about −50° C. and no more than about 100° C. For example, at least one step may be carried out at a temperature of approximately −40° C. By way of another example, at least one step may be carried out at a temperature of approximately 90° C.
It is another aspect of the present invention to provide a method for preparing a purified cannabis extract, comprising (a) contacting cannabis plant material with a liquid mixture of ethanol and water to form a raw extract comprising ethanol, water, at least one cannabinoid or terpene, and at least one protein or lipid; (b) recovering at least most of the ethanol from the raw extract to form a crude cannabis oil; (c) forming a first phase and a second phase from the crude cannabis oil by at least one of (i) contacting the aqueous solution or suspension with at least one of a liquid separating agent and a solid separating agent, and (ii) at least one of centrifugation, filtration, and sedimentation of the aqueous solution or suspension; (d) removing one of the first phase and the second phase to a vessel; and (e) distilling the first phase to form the purified cannabis extract, wherein the first phase comprises at least most of the at least one cannabinoid or terpene present in the crude cannabis oil, wherein the second phase comprises at least most of the at least one protein or lipid present in the crude cannabis oil, and wherein the first and second phases are substantially immiscible.
In embodiments, the at least one cannabinoid or terpene may comprise cannabidiol.
In embodiments, the method may further comprise obtaining a solid fraction of the second phase by at least one of drying the second phase and filtering the second phase; and recycling the solid fraction of the second phase to step (b) as part of the raw extract or to step (c) as part of the crude cannabis oil.
In embodiments, the first phase may comprise at least about 75% of the cannabinoid or terpene present in the crude cannabis oil.
In embodiments, at least one of steps (a), (b), (c), and (d) may be carried out at a temperature of no less than about −50° C. and of no more than about 100° C. For example, at least one of steps (a), (b), (c), and (d) may be carried out at a temperature of approximately −40° C. By way of another example, at least one of steps (a), (b), (c), and (d) may be carried out at a temperature of approximately 90° C.
In embodiments, the purified cannabis extract may be substantially free of proteins, sugars, resin glues, chlorophyll, and lipids.
In embodiments, the purified cannabis extract may comprise at least about 70 wt % cannabinoids and terpenes. The purified cannabis extract may, but need not, comprise at least about 70 wt % cannabidiol.
It is another aspect of the present invention to provide a liquid composition, comprising at least about 70 wt % cannabinoids and terpenes and being substantially free of proteins, sugars, resin glues, chlorophyll, and lipids.
In embodiments, the liquid composition may comprise at least about 70 wt % cannabidiol. The liquid composition may, but need not, be substantially free of cannabidiolic acid.
In embodiments, the liquid composition may be produced by a method comprising (a) providing the aqueous solution or suspension, the aqueous solution or suspension comprising the first and second organic substances; (b) forming a first phase and a second phase from the aqueous solution or suspension by at least one of (i) contacting the aqueous solution or suspension with at least one of a liquid separating agent and a solid separating agent, and (ii) at least one of centrifugation, filtration, and sedimentation of the aqueous solution or suspension; (c) removing one of the first phase and the second phase to a vessel; and (d) distilling the first phase, wherein the first organic substance comprises at least one of a cannabinoid and a terpene, wherein the second organic substance comprises at least one of a protein and a lipid, wherein the first phase comprises substantially all of the first organic substance present in the aqueous solution or suspension and is substantially free of the second organic substance, wherein the second phase comprises substantially all of the second organic substance present in the aqueous solution or suspension and is substantially free of the first organic substance, and wherein the first and second phases are substantially immiscible.
In embodiments, the liquid composition may be produced by a method comprising (a) contacting cannabis plant material with a liquid mixture of ethanol and water to form a raw extract comprising ethanol, water, at least one cannabinoid or terpene, and at least one protein or lipid; (b) recovering at least most of the ethanol from the raw extract to form a crude cannabis oil; (c) forming a first phase and a second phase from the crude cannabis oil by at least one of (i) contacting the aqueous solution or suspension with at least one of a liquid separating agent and a solid separating agent, and (ii) at least one of centrifugation, filtration, and sedimentation of the aqueous solution or suspension; (d) removing one of the first phase and the second phase to a vessel; and (e) distilling the first phase to form the purified cannabis extract, wherein the first phase comprises at least most of the at least one cannabinoid or terpene present in the crude cannabis oil, wherein the second phase comprises at least most of the at least one protein or lipid present in the crude cannabis oil, and wherein the first and second phases are substantially immiscible.
It is another aspect of the present invention to provide a system for preparing a purified plant extract, comprising a centrifugal separation unit, comprising at least one centrifugal separator, configured to receive plant material and a liquid solvent comprising ethanol, mix the plant material and the liquid solvent to form a slurry, and centrifuge the slurry in the centrifugal separator to separate the slurry into a solid residue and a raw extract, wherein the raw extract comprises at least one compound of interest and at least most of the liquid solvent; a filtration unit, comprising a filter assembly, configured to filter the raw extract to remove entrained solid plant material from the raw extract; a concentration unit, comprising an evaporator configured to receive the raw extract and heat the raw extract to remove at least most of the solvent therefrom by evaporation to thereby form a concentrated extract; a settling unit, comprising at least one settling vessel, configured to receive the concentrated extract and cause sedimentation of at least one impurity therefrom; a decarboxylation and degassing unit, comprising an atmosphere heating vessel and a vacuum heating vessel, wherein the atmosphere heating vessel is configured to receive the concentrated extract from the settling unit and heat the concentrated extract under approximately ambient or atmospheric pressure to decarboxylate at least a portion of the concentrated oil to form a decarboxylated oil, wherein the vacuum heating vessel is configured to receive the decarboxylated oil from the atmosphere heating vessel and heat the decarboxylated oil under sub-atmospheric pressure to form a winterized oil; and a short-path distillation unit, comprising at least one short-path distillation apparatus configured to receive the winterized oil from the decarboxylation and degassing unit and distill the winterized oil to form the purified plant extract.
In embodiments, the plant material may be a cannabis plant material.
In embodiments, the at least one compound of interest may comprise at least one cannabinoid or terpene. The at least one compound of interest may, but need not, comprise cannabidiol.
In embodiments, a content of the at least one compound of interest in the purified plant extract may be at least about 70% by weight.
In embodiments, the liquid solvent may consist essentially of (i) between about 92 and about 95 wt % ethanol and (ii) water.
In embodiments, the at least one impurity may comprise at least one protein or lipid.
In embodiments, the system may further comprise a rectification unit, configured to receive evaporated solvent from the concentration unit and recover the solvent for recycle to at least one other unit of the system.
It is another aspect of the present invention to provide a method for preparing a purified plant extract, comprising (a) contacting plant material with a liquid solvent containing ethanol to form a slurry; (b) centrifuging the slurry to form a raw extract comprising at least one compound of interest and at least most of the liquid solvent; (c) filtering the raw extract to remove entrained solid plant material from the raw extract; (d) concentrating the raw extract by heating the raw extract to remove at least most of the solvent therefrom by evaporation to thereby form a concentrated extract; (e) precipitating a sediment comprising at least one impurity from the concentrated extract; (f) decarboxylating the concentrated extract by heating the concentrated extract under approximately ambient or atmospheric pressure to form a decarboxylated oil; (g) heating the decarboxylated oil under sub-atmospheric pressure to form a winterized oil; and (h) distilling the winterized oil by short-path distillation to form the purified plant extract.
In embodiments, the plant material may be a cannabis plant material.
In embodiments, the at least one compound of interest may comprise at least one cannabinoid or terpene. The at least one compound of interest may, but need not, comprise cannabidiol.
In embodiments, a content of the at least one compound of interest in the purified plant extract may be at least about 70% by weight.
In embodiments, the liquid solvent may consist essentially of (i) between about 92 and about 95 wt % ethanol and (ii) water.
In embodiments, the at least one impurity may comprise at least one protein or lipid.
In embodiments, the method may further comprise rectifying the solvent evaporated in step (d) for recycle to at least one of steps (a), (b), and (c).
It is another aspect of the present invention to provide a system for preparing a purified extract, comprising a centrifugal separation unit configured to form a solid residue and a raw extract from a slurry, wherein the raw extract comprises at least one compound of interest and at least most of the liquid solvent; a filtration unit, comprising a filter assembly, configured to filter the raw extract to remove entrained plant material from the raw extract; a concentration unit, comprising an evaporator configured to receive the raw extract and heat the raw extract to remove at least most of the solvent therefrom by evaporation to thereby form a concentrated extract; a settling unit, comprising at least one settling vessel, configured to receive the concentrated extract and cause sedimentation of at least one impurity therefrom, a decarboxylation and degassing unit, comprising an atmospheric heating vessel and a vacuum heating vessel, wherein the atmosphere heating vessel is configured to receive the concentrated extract from the settling unit, mix the concentrated extract with a brine solution and at least one acid under approximately ambient or atmospheric pressure to remove at least one additional impurity from the concentrated extract, and form a winterized oil without a majority of the at least one additional impurity; and a short-path distillation unit, comprising at least one short-path distillation apparatus configured to receive the winterized oil from the decarboxylation and degassing unit and distill the winterized oil to form the purified plant extract.
In some embodiments, the centrifugal separation unit comprises at least one centrifugal separator configured to receive solid plant material from a solid plant material source and a liquid solvent comprising ethanol from a separate solvent source, mix the plant material and the liquid solvent to form the slurry, and centrifuge the slurry in the at least one centrifugal separator to separate the slurry into the solid residue and the raw extract.
In some embodiments, the at least one acid includes a phosphoric acid and a citric acid.
In some embodiments, the at least one additional impurity comprises at least one sugar.
In some embodiments, the atmosphere heating vessel is configured to receive the concentrated extract from the settling unit and heat the concentrated extract under approximately ambient or atmospheric pressure to decarboxylate at least a portion of the concentrated oil to form the decarboxylated oil, wherein the vacuum heating vessel is configured to directly receive the decarboxylated oil from the atmosphere heating vessel and heat the decarboxylated oil under sub-atmospheric pressure to form the winterized oil.
In some embodiments, the system further comprises a static separator configured to remove the at least one impurity or the at least one additional impurity.
In some embodiments, the plant material is a cannabis plant material, wherein the at least one compound of interest comprises at least one cannabinoid including cannabidiol or terpene.
In some embodiments, the liquid solvent consists essentially of (i) between about 92 and about 95 wt % ethanol and (ii) water.
In some embodiments, the at least one impurity comprises at least one protein or lipid.
In some embodiments, the system further comprises a rectification unit, configured to receive evaporated solvent from the concentration unit and recover the solvent for recycle to at least one other unit of the system.
It is another aspect of the present invention to provide a method for preparing a purified extract that may include, but is not limited to, (a) contacting plant material with a liquid solvent containing ethanol to form a slurry; (b) centrifuging the slurry to form a raw extract comprising at least one compound of interest and at least most of the liquid solvent; (c) filtering the raw extract to remove entrained solid plant material from the raw extract; (d) concentrating the raw extract by heating the raw extract to remove at least most of the solvent therefrom by evaporation to thereby form a concentrated extract; (e) precipitating a sediment comprising at least one impurity from the concentrated extract; (f) mixing the concentrated extract with a brine solution and at least one acid; (g) washing the concentrated extract, brine solution, and at least one acid with water to remove at least a portion of at least one additional impurity; (h) decarboxylating the concentrated extract by heating the concentrated extract under approximately ambient or atmospheric pressure to form a decarboxylated oil; (i) heating the decarboxylated oil under sub-atmospheric pressure to form a winterized oil without the at least one additional impurity; and (j) distilling the winterized oil by short-path distillation to form the purified plant extract. In some embodiments, the method further comprises rectifying the solvent evaporated in step (d) for recycle to at least one of steps (a), (b), and (c).
In some embodiments, after the concentrated extract is mixed with the brine solution and at least one acid, the at least one additional impurity is turned into a water-soluble electrolyte. The method is not limited to steps in the order identified. The steps of the method can be performed in any order in various embodiments. For example, steps (f) through (i) can be performed in a different order than listed above. Specifically, in some embodiments, step (h) occurs before step (f). In other embodiments, steps (f) and (h) occur concurrently and step (g) occurs thereafter.
In some embodiments, contacting the plant material with the liquid solvent containing ethanol to form the slurry comprises: mixing, within at least one centrifugal separation unit, solid plant material received from a solid plant material source with the liquid solvent containing ethanol received from a separate solvent source to form the slurry, wherein the slurry is centrifuged within the at least one centrifugal separation unit to form the raw extract comprising the at least one compound of interest and the at least most of the liquid solvent.
In some embodiments, the at least one acid includes a phosphoric acid and a citric acid.
In some embodiments, the at least one additional impurity comprises at least one sugar.
In some embodiments, the mixing the concentrated extract with the brine solution and the at least one acid, the turning at least one additional impurity into the water-soluble electrolyte, and the washing the concentrated extract, brine solution, and at least one acid with water to remove the at least a portion of the at least one additional impurity occurs in a first vessel. The concentrated extract is then heated in said first vessel to form the decarboxylated oil. The decarboxylated oil is heated in a second vacuumized vessel directly connected to said first vessel to form the winterized oil.
In some embodiments, the plant material is a cannabis plant material, wherein the at least one compound of interest comprises at least one cannabinoid including cannabidiol or terpene.
In some embodiments, a content of the at least one compound of interest in the purified plant extract is at least about 70% by weight.
In some embodiments, the liquid solvent consists essentially of (i) between about 92 and about 95 wt % ethanol and (ii) water.
In some embodiments, the at least one impurity comprises at least one protein or lipid.
For purposes of further disclosure and to comply with applicable written description and enablement requirements, the following references generally relate to systems and methods for extracting a compound or compounds of interest from plant material and/or separating organic compounds and impurities from an aqueous solution or suspension, and are hereby incorporated by reference in their entireties:
U.S. Pat. No. 9,937,218, entitled “Systems and methods for cannabinoid and terpene extraction and purification,” issued 10 Apr. 2018 to Towle.
U.S. Pat. No. 9,994,464, entitled “Method and devices for de-emulsifying and complexing organic compounds in emulsions,” issued 12 Jun. 2018 to Dietz.
The phrases “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. When each one of A, B, and C in the above expressions refers to an element, such as X, Y, and Z, or class of elements, such as X1-Xn, Y1-Ym, and Z1-Zo, the phrase is intended to refer to a single element selected from X, Y, and Z, a combination of elements selected from the same class (e.g., X1 and X2) as well as a combination of elements selected from two or more classes (e.g., Y1 and Zo).
The term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably.
It should be understood that every maximum numerical limitation given throughout this disclosure is deemed to include each and every lower numerical limitation as an alternative, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this disclosure is deemed to include each and every higher numerical limitation as an alternative, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this disclosure is deemed to include each and every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.
The preceding is a simplified summary of the disclosure to provide an understanding of some aspects of the disclosure. This summary is neither an extensive nor exhaustive overview of the disclosure and its various aspects, embodiments, and configurations. It is intended neither to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure but to present selected concepts of the disclosure in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other aspects, embodiments, and configurations of the disclosure are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present disclosure. The drawings are not to be construed as limiting the disclosure to only the illustrated and described examples.
As used herein, unless otherwise specified, the term “cannabis” refers to any plant in the genus Cannabis.
As used herein, unless otherwise specified, the term “hemp” refers to cannabis plant material containing no more than about 0.3% tetrahydrocannabinol by weight.
As used herein, unless otherwise specified, the term “plant material” refers to whole plants and/or parts of plants that contain one or more compounds to be extracted, including but not limited to aerial parts, leaves, stems, flowering heads, fruits, and/or roots. “Plant material” may be freshly harvested plants or parts of plants, plants or parts of plants that have been subjected to one or more pre-treatment steps (e.g., drying, removal of debris, etc.), and/or plants or parts of plants that have been frozen or pelletized.
Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Further, the present disclosure may use examples to illustrate one or more aspects thereof. Unless explicitly stated otherwise, the use or listing of one or more examples (which may be denoted by “for example,” “by way of example,” “e.g.,” “such as,” or similar language) is not intended to and does not limit the scope of the present disclosure.
Although the following description generally refers to embodiments in which the methods and systems of the invention are employed to extract, e.g., cannabinoids from, e.g., cannabis, it is to be expressly understood that the present invention may be suitably applied to any plant or other biomass material to extract any compound that may be obtained by distillation. By way of non-limiting example, the present invention may be employed to extract essential oils or other volatile compounds from spices, fruits, flowers, or any other suitable plant material, as such embodiments are within the scope of the present invention.
One advantage of methods and systems of the present invention is that cannabis extracts produced by the present invention may contain a blend of cannabinoids in approximately the same proportion as are present in the raw cannabis plant material. In other words, little or no fractionation of cannabinoids may be observed so a “Full Spectrum” product is produced that reflects the cannabinoid profile of the feedstock.
Crude oils produced from conventional ethanol extraction processes generally comprise at least some lipids, sugars, resin glues, chlorophyll, and/or proteins dissolved in water. Additionally or alternatively, such crude oils may comprise carboxylic acids, phospholipids, glycolipids, glyceroglycolipids, phenols, sterols, squalene, plant dyes, such as chlorophylls and carotenes, sinapines, peptides, proteins, carbohydrates, lipoproteins, waxes and/or fatty alcohols. Thereby, the carboxylic acids, phospholipids, glycolipids, glyceroglycolipids, phenols, sterols, squalene, plant dyes, such as chlorophylls and carotenes, sinapines, peptides, proteins, carbohydrates, lipoproteins, flavoring agents, waxes and/or fatty alcohols may be present individually or as a mixture in the aqueous solutions or suspensions, e.g., for example, as a mixture of peptides, sterols, and carbohydrates or a mixture of glycolipids and phospholipids. Aqueous solutions and suspensions suitable for refinement according to the present invention may also contain phospholipids, glycolipids, glyceroglycolipids, phenols, sterols, squalene, flavorings, vegetable dyes, such as chlorophylls and carotenoids, and/or sinapines apart from carboxylic acids.
According to the present invention, proteins, lipids, sugars, resin glues, chlorophyll, and similar organic substances that may be considered impurities or otherwise undesirable may be separated from cannabinoids, terpenes, and other compounds of interest by separating crude aqueous solutions or suspensions, e.g., crude extracts or oils of cannabis, into two distinct phases, one phase being relatively rich in the cannabinoids/terpenes and relatively poor in the proteins, lipids, sugars, resin glues, chlorophyll, etc., and the other phase being relatively poor in the cannabinoids/terpenes and relatively rich in the proteins, lipids, sugars, resin glues, chlorophyll, etc. This phase separation may be accomplished by any one or more of several means. By way of first non-limiting example, phase separation may be achieved by chemical means, e.g., by contacting the aqueous solution or suspension with a liquid or solid separating agent. By way of second non-limiting example, phase separation may be achieved by physical means, e.g., by centrifugation, filtration, and/or sedimentation of the aqueous solution or suspension.
Chemical separating agents in any form, e.g., solids, powders, aqueous dispersions of solids, etc., can be added to crude extracts and oils as disclosed in the methods described herein. In embodiments, the addition may be carried out by mixing, and/or at a maximum temperature of about 100° C., and/or with a laminar agitator.
Aqueous extraction mixtures suitable for separation according to the present invention may contain, besides the above-mentioned proteins, lipids, sugars, resin glues, chlorophyll, and carboxylic acids, phospholipids, glycolipids, glyceroglycolipids, phenols, sterols, squalenes, and/or vegetable dyes, such as chlorophylls and carotenes. These and other similar organic substances may likewise be separated from cannabinoids, terpenes, and/or other compounds of interest according to the present invention.
Methods of the present invention may or may not include adjusting the pH of the crude plant extract or oil or other aqueous solution or suspension of interest. In some embodiments, the pH of one or both phases after separation may be approximately equal to that of the initial aqueous solution, i.e., before separation. Methods of the present invention may thus be useful to treat acidic solutions or suspensions, basic solutions or suspensions, and/or neutral solutions or suspensions.
The present invention may be useful to separate proteins, sugars, resin glues, chlorophyll, and/or lipids from other compounds of interest regardless of the physical nature of the initial aqueous suspension or solution from which the compounds are to be separated. By way of first non-limiting example, the aqueous solution or suspension may be a true solution, i.e., the protein(s) and/or lipid(s) may be dissolved throughout an aqueous solvent. By way of second non-limiting example, the aqueous solution or suspension may be a colloid, i.e., the protein(s) and/or lipid(s) may be dispersed throughout an aqueous liquid dispersion medium as solid or liquid particles that are too small for sedimentation, or sufficiently small that the sedimentation time is impractically long. By way of third non-limiting example, the aqueous solution or suspension may be a non-colloidal suspension, i.e., the protein(s), sugar, resin glues, chlorophyll, and/or lipids may be dispersed throughout an aqueous liquid dispersion medium as macroscopic solid or liquid particles.
Particularly, the inventive process is suitable for aqueous solutions or suspensions that originate from solvent extraction processes for extracting one or more compounds of interest from solid material, and especially from ethanol extraction processes for extracting one or more compounds of interest from plant material, e.g., cannabis plant material. As described throughout this disclosure, crude extracts resulting from such processes may contain, in addition to a compound of interest (e.g., a cannabinoid or terpene), water and water-soluble proteins, sugars, resin glues, chlorophyll, and lipids extracted from the plant material. Typically, such extracts must be distilled to provide a purified extract, but heating of the crude extract may result in solidification or sedimentation of the proteins, sugars, resin glues, chlorophyll, and/or lipids, which may foul process equipment. By separating a phase containing organic impurities such as proteins, sugars, resin glues, chlorophyll, and lipids from a phase containing the compound of interest, the present invention greatly mitigates the need to unclog or clean process equipment, resulting in greater process uptime and reduced cost.
Notably, as described herein the inventive process is suitable to remove sugars and resin glue from formed crude oil and the process equipment that houses the formed crude oil, in addition to the removal of impurities such as proteins, lipids, chlorophyll, or the like. This is beneficial as the sugars and resin glue may clog the process equipment and make distillation difficult. Removing sugars and resin glue in addition to proteins and lipids may reduce spent time and cost while saving electricity and improving yield during the distillation process.
In embodiments, the methods of the present invention result in the formation of an aqueous phase comprising protein(s) and/or lipid(s) that can be re-processed or further processed to separate residual compounds of interest, e.g., cannabinoids or terpenes, remaining in such phase. Particularly, the protein/lipid phase resulting from separations according to the present invention can be filtered and/or dried to produce a solid fraction, which may then be subjected to an extraction process, e.g., recycled to an earlier solvent extraction process. In this way, methods of the present invention are suitable not only to avoid fouling of process equipment in solvent extraction/distillation processes for purification of compounds of interest, but also to improve the overall recovery of the compounds of interest in such processes. Such filtration and/or drying may, in some embodiments, also result in a relatively high-purity liquid fraction of water, which may likewise be useful in other processes and/or steps.
One advantage of the present invention relative to conventional methods is that both the compound(s) of interest, e.g., cannabinoids and terpenes, and the protein(s) and lipid(s) to be separated from the compounds of interest may be obtained without significant physical or chemical degradation or decomposition. More specifically, embodiments of the methods of the present invention do not require exposure of sensitive organic compounds to extreme temperatures or pressures, or to strong acids, bases, or other chemicals that may degrade, cause hydrolysis of, or otherwise damage the compound(s) of interest, protein(s), or lipid(s); in fact, it may in many embodiments be preferable to carry out the methods of the present invention at moderate temperatures (e.g., between about −50° C. and about 100° C., between about −40° C. and about 90° C., between about 15° C. and 75° C., between about 20° C. and about 50° C., or between about 25° C. and about 35° C., or in some embodiments no more than about 75° C.). As a result, either phase, or both phases, can be further processed to yield a safe and high-purity product, e.g., a cannabis distillate comprising at least about 70% cannabinoids and/or terpenes by weight. Proteins, sugars, resin glues, chlorophyll, and lipids separated from the aqueous solution or suspension may likewise be in a chemically and physically intact and/or neutral form suitable for further use, e.g., in foods, cosmetic products, pharmaceuticals, flavoring agents, etc.
Neutral lipids may present particular separation challenges because they typically cannot be separated from aqueous solutions or suspensions by physical means such as centrifugation. By the practice of the present invention, separation of the neutral lipids present in aqueous solutions and suspensions can be obtained, e.g., by increasing a separation temperature and inducing aggregation of the neutral lipids. In this way, the methods of the present invention enable the separation of neutral fats from aqueous solutions and suspensions, either from compounds of interest or from proteins, sugars, resin glues, chlorophyll, and other lipids.
Embodiments of the present invention may advantageously result in the formation of a phase containing a relatively high proportion of water and a phase containing a relatively low proportion of water. Particularly, in embodiments, the methods of the present invention may produce a water-poor phase that is rich in the compound(s) of interest, e.g., cannabinoids and terpenes, and a water-rich phase that is rich in impurities, e.g., protein(s), sugars, resin glues, chlorophyll, and lipids. The water-poor phase can then be further purified, e.g., by distillation or other temperature- or pressure-intensive methods, without causing fouling or clogging of process equipment, while the water-rich phase can be recycled, purged, or further purified by any of several well-known means, such as the use of decanters, separators, filter technology, vacuum drying, inert gas drying, heating, etc. to separate organic aggregates, e.g., proteins, sugars, resin glues, chlorophyll, and lipids. In addition, the shelf life of the compound(s) of interest in the water-poor phase may be extended, due to the avoidance of physical contact with impurities and water for an extended period, and the proteins, sugars, resin glues, chlorophyll, and lipids may likewise be suitable for later use in other products or processes.
Embodiments of the present invention allow more efficient and effective separation of compounds of interest, e.g., cannabinoids and terpenes, from protein and lipid impurities than conventional separation methods. By way of first non-limiting example, methods of the present invention may allow for formation of a cannabinoid- and/or terpene-rich phase that comprises at least about 50 wt %, at least about 55 wt %, at least about 60 wt %, at least about 65 wt %, at least about 70 wt %, at least about 75 wt %, at least about 80 wt %, at least about 85 wt %, at least about 90 wt %, at least about 95 wt %, at least about 96 wt %, at least about 97 wt %, at least about 98 wt %, or at least about 99 wt % of the cannabinoids and/or terpenes present in the input aqueous solution or suspension. By way of second non-limiting example, methods of the present invention may allow for formation of a protein- and/or lipid-rich phase that comprises at least about 50 wt %, at least about 55 wt %, at least about 60 wt %, at least about 65 wt %, at least about 70 wt %, at least about 75 wt %, at least about 80 wt %, at least about 85 wt %, at least about 90 wt %, at least about 95 wt %, at least about 96 wt %, at least about 97 wt %, at least about 98 wt %, or at least about 99 wt % of the proteins, sugars, resin glues, chlorophyll, and/or lipids present in the input aqueous solution or suspension. By way of third non-limiting example, methods of the present invention may allow for formation of a protein- and/or lipid-poor phase that comprises no more than about 50 wt %, no more than about 45 wt %, no more than about 40 wt %, no more than about 35 wt %, no more than about 30 wt %, no more than about 25 wt %, no more than about 20 wt %, no more than about 15 wt %, no more than about 10 wt %, no more than about 5 wt %, no more than about 4 wt %, no more than about 3 wt %, no more than about 2 wt %, or no more than about 1 wt % of the proteins, sugars, resin glues, chlorophyll, and/or lipids present in the input aqueous solution or suspension. By way of fourth non-limiting example, methods of the present invention may allow for formation of a cannabinoid- and/or terpene-poor phase that comprises no more than about 50 wt %, no more than about 45 wt %, no more than about 40 wt %, no more than about 35 wt %, no more than about 30 wt %, no more than about 25 wt %, no more than about 20 wt %, no more than about 15 wt %, no more than about 10 wt %, no more than about 5 wt %, no more than about 4 wt %, no more than about 3 wt %, no more than about 2 wt %, or no more than about 1 wt % of the cannabinoids and/or terpenes present in the input aqueous solution or suspension.
In some embodiments, separation of proteins, sugars, resin glues, chlorophyll, and/or lipids from compounds of interest may be effectuated by initiating aggregation and subsequent sedimentation of proteins, sugars, resin glues, chlorophyll, and/or lipids from the aqueous solutions or suspension, thus leaving behind a phase containing the compound of interest and having a diminished content of proteins, sugars, resin glues, chlorophyll, and/or lipids. In these and other embodiments, separation of proteins, sugars, resin glues, chlorophyll, and/or lipids from compounds of interest may be effectuated by initiating separation of the solution into a water-poor or hydrophobic phase, which preferentially includes oily, hydrophobic, or poorly water-soluble contents of the aqueous solution or suspension (e.g., cannabinoids, terpenes, etc.), and a water-rich or hydrophilic phase, which preferentially includes water and hydrophilic, amphiphilic, or highly water-soluble contents of the aqueous solution or suspension (e.g., proteins, sugars, resin glues, chlorophyll, lipids, etc.). In some embodiments, it may be possible to decant or otherwise separate the water of the protein- or lipid-rich phase from the proteins, sugars, resin glues, chlorophyll, and lipids, e.g., when the aqueous solution or suspension is separated into two liquid phases and the proteins, sugars, resin glues, chlorophyll, and lipids subsequently aggregate and precipitate out of a water-rich liquid phase. Alternatively, solid or semi-solid aggregates of proteins, sugars, resin glues, chlorophyll, lipids, and/or other impurities may, standing alone, constitute all or a majority of the mass or volume of a phase, in which case it may be possible to separate the entire liquid contents of the reactor or vessel in which separation is being carried out, e.g., by means of a sieve or filter. In any of these embodiments, either phase may be washed or further processed to improve fractionation still further.
Referring now to
In the providing step 110 of the method 100, an aqueous solution or suspension, comprising a first organic substance and a second organic substance, is provided. In embodiments, the first organic substance generally includes at least one cannabinoid, at least one terpene, or a combination or mixture thereof, and the second organic substance generally includes at least one protein, at least one lipid, or a combination or mixture thereof, but it is to be expressly understood that various other organic substances may be suitable, as described throughout this disclosure. In some preferred embodiments, the first organic substance may comprise cannabidiol (CBD), and the second organic substance may comprise a combination or mixture of at least partially water-soluble, water-miscible, and/or hydrophilic protein(s), sugars, resin glues, chlorophyll, and/or lipids, particularly protein(s), sugar(s), resin glues, chlorophyll, and/or lipid(s) susceptible to solidification (and thus fouling or clogging of process equipment) upon heating. In many embodiments, the aqueous solution may be a crude cannabis extract, and particularly the product of an ethanol extraction process for extraction of a compound of interest (i.e., the first organic substance or a component thereof) from cannabis plant material.
In the forming step 120 of the method 100, the aqueous solution or suspension is separated into a first phase and a second phase by any suitable means. By way of first non-limiting example, the first and second phases may be formed by contacting the aqueous solution or suspension with a solid separating agent and/or a liquid separating agent; in embodiments, a liquid separating agent may be a liquid (e.g., aqueous) solution or dispersion of a solid separating agent (e.g., a copper salt, a calcium salt, a sodium salt, a magnesium salt, silica, etc.). By way of second non-limiting example, the first and second phases may be formed by centrifuging the aqueous solution or suspension. By way of a third non-limiting example, the first and second phases may be formed by filtering the aqueous solution or suspension. By way of a fourth non-limiting example, the first and second phases may be formed by causing or triggering sedimentation of solid particles (e.g., comprising protein(s), sugars, resin glues, chlorophyll, and/or lipids) from the aqueous solution or suspension. Generally, the first phase resulting from forming step 120 is a first substance-rich phase, e.g., a cannabinoid- and/or terpene-rich phase (e.g., comprising at least most, and in embodiments at least 75%, of cannabinoids and/or terpenes in the aqueous solution or suspension), and the second phase resulting from forming step 120 is a protein- and/or lipid-rich phase (e.g., comprising at least most of proteins, sugars, resin glues, chlorophyll, and/or lipids in the aqueous solution or suspension). Typically, the first and second phases may be substantially immiscible to facilitate removing step 130.
In the removing step 130 of the method 100, one of the first and second phases formed in forming step 120 is removed to a vessel separate from that in which forming step 120 is carried out. By way of first non-limiting example, the first phase may be skimmed or otherwise removed from a surface of the second phase where the first and second phases are liquids and the first phase is less dense than the second phase. By way of second non-limiting example, the second phase may be filtered or precipitated from the first phase where the first phase is liquid and the second phase is solid or mostly solid.
The method 100 may optionally include any one or more additional steps not illustrated in
In many embodiments, it may be preferable for the steps of the method 100 to be carried out at approximately ambient temperatures, or at only slightly elevated temperatures. Particularly, it may be preferable to ensure that the steps of the method 100 are carried out at temperatures below those at which proteins, sugars, resin glues, chlorophyll, and/or lipids of the aqueous solution or suspension may solidify, e.g., no more than about 100° C.
Referring now to
In the contacting step 210 of the method 200, plant material is subjected to a solvent extraction process, and in particular embodiments an ethanol extraction process, by being contacted with a liquid solvent (e.g., a mixture of ethanol and water). As a result of contacting step 210, a raw extract is produced; the raw extract typically comprises the solvent, a compound or compounds of interest (e.g., cannabinoids and/or terpenes, including but not limited to cannabidiol), and proteins, sugars, resin glues, chlorophyll, and/or lipids soluble in the solvent or a component thereof.
In the recovering step 220 of the method 200, the solvent or a portion thereof (e.g., ethanol) is removed from the raw extract and optionally recycled to contacting step 210. Removal and recovery of at least a portion of the solvent generally improves the efficiency of subsequent processing steps and results in a purer finished extract.
In the forming step 230 of the method 200, the crude oil is separated into a first phase and a second phase by any suitable means. By way of first non-limiting example, the first and second phases may be formed by contacting the crude oil with a solid separating agent and/or a liquid separating agent; in embodiments, a liquid separating agent may be a liquid (e.g., aqueous) solution or dispersion of a solid separating agent (e.g., a copper salt, a calcium salt, a sodium salt, a magnesium salt, silica, etc.). By way of second non-limiting example, the first and second phases may be formed by centrifuging the crude oil. By way of third non-limiting example, the first and second phases may be formed by filtering the crude oil. By way of fourth non-limiting example, the first and second phases may be formed by causing or triggering sedimentation of solid particles (e.g., comprising protein(s), sugars, resin glues, chlorophyll, and/or lipids) from the crude oil. Generally, the first phase resulting from forming step 230 is a first substance-rich phase, e.g., a cannabinoid- and/or terpene-rich phase (e.g., comprising at least most, and in embodiments at least 75%, of cannabinoids and/or terpenes in the aqueous solution or suspension, and having a low proportion of proteins, sugars, resin glues, chlorophyll, and/or lipids), and the second phase resulting from forming step 230 is a protein- and/or lipid-rich phase (e.g., comprising at least most of proteins, sugars, resin glues, chlorophyll, and/or lipids in the aqueous solution or suspension, and having a low proportion of substances of interest such as cannabinoids and/or terpenes). Typically, the first and second phases may be substantially immiscible to facilitate removing step 240.
In the removing step 240 of the method 200, one of the first and second phases formed in forming step 230 is removed to a vessel separate from that in which forming step 230 is carried out. By way of first non-limiting example, the first phase may be skimmed or otherwise removed from a surface of the second phase where the first and second phases are liquids and the first phase is less dense than the second phase. By way of second non-limiting example, the second phase may be filtered or precipitated from the first phase where the first phase is liquid and the second phase is solid or mostly solid.
In the distilling step 250 of the method 200, the first phase, i.e., the phase containing the compound or compounds of interest (e.g., cannabinoids and/or terpenes), is distilled to further purify the first phase and produce a purified extract.
The method 200 may optionally include any one or more additional steps not illustrated in
In many embodiments, it may be preferable for at least one of, and in some embodiments all of, the contacting step 210, the recovering step 220, the forming step 230, and the removing step 240 to be carried out at approximately ambient temperatures, or at only slightly elevated temperatures. Particularly, it may be preferable to ensure that at least one of these steps of the method 200 is carried out at temperatures below those at which proteins, sugars, resin glues, chlorophyll, and/or lipids of the aqueous solution or suspension may solidify, e.g., no more than about 100° C.
The method 200 may be suitable to obtain a cannabis plant extract having a high proportion of cannabinoids, and in particular a high proportion of cannabidiol. Typically, the cannabinoid content of the purified extract may be at least about 70 wt %, and in some embodiments up to about 80 wt %. The purified extract may be substantially free of proteins, sugars, resin glues, chlorophyll, and/or lipids, or may have a significantly lower content of proteins, sugars, resin glues, chlorophyll, and/or lipids relative to cannabis plant extracts obtained by conventional methods.
Referring now to
One advantage of the present invention is that it permits the use of commercially available ethanol sources that may comprise a significant fraction of water. Particularly, the ethanol used in the system of the present invention, e.g., the alcohol present in the alcohol tank 301 and injected by the alcohol pump 302 into the centrifugal separator(s) 304, may, in embodiments, comprise up to about 8% water; it may be possible to use ethanol in which the water fraction is even higher. This feature greatly reduces the cost, and greatly increases the availability, of the ethanol solvent for use in the system.
Although not illustrated in
It is to be expressly understood that, in embodiments (like that illustrated in
Regardless of the number and arrangement of the centrifugal separator(s) 304, the centrifugal separation unit 300 produces two materials: a solid residue and a crude oil. The solid residue is generally “wet,” i.e., comprising at least some residual ethanol and/or water, and the crude oil generally comprises compounds extracted from the cannabis plant material (e.g., cannabinoids and/or terpenes), solvent, and in many cases some residual solids. The solid residue is discarded (although it may in certain applications and embodiments be retained and optionally subjected to further processing), but the crude oil is then passed to the filter unit 400 illustrated in
Referring now to
Referring now to
As illustrated, the concentrated oil is sent from the concentration evaporator 501 to the static separation unit 700 illustrated in
Referring now to
Upon rectification, the now substantially pure ethanol is cooled in the cooler 605, optionally stored in one or more storage tanks 602, and recycled; generally, the rectified ethanol is recycled to the centrifugal separation unit 300, and particularly to the alcohol tank 301, to be reused as part of the ethanol extraction solvent, but may also be recycled to other process units, such as the filter unit 400 and/or the concentration unit 500.
Referring now to
In some (but by no means all) embodiments, static separation of the crude oil received from the concentration unit 500 may be aided by any one or more suitable means in the static separation unit 700 in addition to settling tank(s) 701. By way of first non-limiting example, the crude oil may be contacted with a solid separating agent and/or a liquid separating agent; in embodiments, a liquid separating agent may be a liquid (e.g., aqueous) solution or dispersion of a solid separating agent (e.g., a copper salt, a calcium salt, a sodium salt, a magnesium salt, silica, etc.). By way of second non-limiting example, the crude oil may be centrifuged. By way of third non-limiting example, the crude oil may be filtered.
In some embodiments, the static separation unit 700 removes waxes, chlorophyll, proteins, and other impurities. In some, but by no means all, embodiments, the static separation be carried out over a period of between about 4 and about 10 hours, or between about 7 and about 9 hours. In one embodiment, the crude oil received from the concentration unit 500 is in the static separation unit 700 for about 8 hours.
In some embodiments, the static separation unit 700 and associated separation takes place before the crude oil is mixed with one or more acid and/or a brine solution and at least some of an additional impurity (e.g., sugar) is removed. In other embodiments, the static separation unit 700 and associated separation takes place after the crude oil is mixed with one or more acid and/or a brine solution and at least some of an additional impurity (e.g., sugar) is removed.
Referring now to
The atmosphere heating vessel 811 receives the settled crude oil from the static separation unit 700 and heats the settled crude oil under approximately ambient or atmospheric pressure; this heating steps decarboxylates cannabinoids in the crude oil, which are often present in larger quantities in their carboxylated, i.e., carboxylic acid, forms (which are generally biologically inactive) than in their biologically active free or neutral forms.
The heating of the crude oil in the atmosphere heating vessel 811 may, in some embodiments, also accomplish various “winterization” processes (i.e., removal of unwanted compounds) and may cause gases dissolved in the oil to be removed. With the addition of phosphoric acid, citric acid, and/or a brine solution, unwanted compounds such as proteins, resins, sugars, lipids, and chlorophyll, and other unwanted compounds as described throughout the present disclosure are at least partly removed from the crude oil, creating the “winterized” oil via the “winterization” processes. In some, but by no means all, embodiments, the heating in the atmosphere heating vessel 811 may be carried out under about atmospheric pressure. In some, but by no means all, embodiments, the heating in the atmosphere heating vessel 811 may be to a temperature of between about 80 and about 90° C., or between about 90 and about 95° C. In various embodiments, the heating in the atmosphere heating vessel 811 may only be to a temperature of between about 20° C. and about 70° C., or between about 30° C. and about 60° C. In some, but by no means all, embodiments, the heating in the atmosphere heating vessel 811 may be carried out over a period of between about 10 and about 15 minutes, or between about 20 and about 25 minutes. In some, but by no means all, embodiments, the heating in the atmosphere heating vessel 811 may take place in the presence of a catalyst.
Once decarboxylation is substantially complete, the vacuum heating vessel 821, which is maintained at a sub-atmospheric pressure (and in some embodiments vacuum or near-vacuum) by the vacuum pump 822, receives the decarboxylated oil from the atmosphere heating vessel 821 via a conduit. In the vacuum heating vessel 821, the decarboxylated oil is further heated under sub-atmospheric pressure as a preheating step before entering the short-path distillation unit 900 illustrated in
In various embodiments, at least one acid 812, 813 and/or a brine solution 814 are added to a secondary tank positioned prior to the atmospheric heating vessel 811. The acid is phosphoric acid 812 and/or citric acid 813 in some embodiments. The at least one acid 812, 813 is added to crude oil to turn heat-sensitive impurities such as protein, chlorophyll, sugar, and resin glue into water-soluble electrolytes, which are brought out by washing with water. The purpose of saturated brine is to increase the density of water and facilitate stratification, i.e., the oil floating on top of the brine 814. Thus, in some embodiments, the additional step of adding at least one acid 812, 813 and/or a brine solution 814 occurs before the oil enters the atmospheric heating vessel 811. In some embodiments, the oil, acid, and/or brine mixture is washed with water in the same vessel to which the acid and/or brine are added such that the additional impurities are removed in the same vessel. The atmospheric heating vessel 811 can remove water from the mixture if the acid(s) and/or brine are added before the oil enters the atmospheric heating vessel 811.
As discussed herein, the at least one acid 812, 813 and/or brine solution 814 can be added to the decarboxylation and degassing unit 800, including in the atmosphere heating vessel 811 or an additional vessel positioned between the atmosphere heating vessel 811 and the vacuum heating vessel 821. Thus, in some embodiments, the vacuum heating vessel 821 removes water from the mixture if the acid(s) and/or brine are added before the oil enters the vacuum heating vessel 821. This is true if the acid(s) and/or brine are added in the atmosphere heating vessel 811 or are added in an additional vessel positioned between the atmosphere heating vessel 811 and the vacuum heating vessel 821.
In some embodiments, at least one acid and a brine solution may be added to the decarboxylation and degassing unit 800 to assist in removing impurities from the crude oil. For example, phosphoric acid 812, citric acid 813, and/or a brine solution 814 are additionally mixed in the atmosphere heating vessel 811 with the settled crude oil. Mixing the phosphoric acid 812 and the citric acid 813 into the crude oil turns heat-insensitive impurities in the crude oil including, but not limited to, protein, chlorophyll, sugar, and resin glue into water-soluble electrolytes. Where the impurities are separated from the crude oil by washing with water, the brine solution 814 allows the crude oil to float on top of the water by increasing the density of water, facilitating stratification of the impurities from the crude oil.
It is noted that the addition of the phosphoric acid 812, the citric acid 813, and the brine solution 814 allows for a temperature range between about −50° C. and about 100° C., or between about −40° C. and about 90° C., during the preparation of a purified plant extract from plant material. In general, typical processes use lower temperatures to reduce impurities including, but not limited to, proteins, resin glue, and chlorophyll. However, these temperatures are not suitable to remove sugars from the crude oil by themselves, causing difficulties in future distillation steps where the sugar caramelizes. Additionally, if the sugars are not removed, then they caramelize during heated steps.
In various embodiments, a second vacuum heating vessel can be used after the first vacuum heating vessel 821. The second vacuum heating vessel can remove any extra water in the mixture.
In some embodiments, the decarboxylation and degassing unit 800 may be effective to convert substantially all of the carboxylated/carboxylic acid form of the compound of interest to the corresponding free or neutral form. By way of non-limiting example, the decarboxylation and degassing unit 800 may be effective to convert substantially all of the cannabidiolic acid present in the settled crude oil to cannabidiol.
Referring now to
The finished product of the system described herein, obtained from the short-path distillation unit 900, is a yellow-colored or golden cannabinoid and/or terpene oil of high purity and quality. In embodiments, cannabinoids may make up at least about 70 wt %, and preferably at least about 80 wt %, of the end product. In some embodiments, cannabidiol may make up at least about 70 wt %, and preferably at least about 80 wt %, of the end product.
Referring now to
In the contacting step 1010 of the method 1000, cannabis plant material is subjected to a solvent extraction process, particularly an ethanol extraction process, by being contacted with a liquid solvent (e.g., a mixture of ethanol and water). As a result of contacting step 1010, a raw extract or slurry is produced; the raw extract typically comprises the solvent, a compound or compounds of interest (e.g., cannabinoids and/or terpenes, including but not limited to cannabidiol), and proteins, sugars, resin glues, chlorophyll, and/or lipids soluble in the solvent or a component thereof.
In the centrifugation step 1020 of the method 1000, the raw extract or slurry is centrifuged to produce a solid residue and a crude oil. The crude oil, comprising at least most of the solvent and compound or compounds of interest, is generally free of very large pieces of solid cannabis plant material, but may still contain smaller pieces.
In the filtration step 1030 of the method 1000, the crude oil is filtered by any suitable means to produce a filtered crude oil. At this point, the filtered crude oil is generally free of macroscopic plant matter, but may still contain dissolved or suspended solids, e.g., proteins, sugars, resin glues, chlorophyll, and lipids.
In the concentration step 1040 of the method 1000, the solvent or a portion thereof (i.e., ethanol) is removed from the crude oil and optionally recycled to contacting step 1010 or another process step. Concentration step 1040 is generally accomplished by heating the filtered crude oil to selectively evaporate the ethanol solvent, which may then be condensed for recycle or removal. Removal and recovery of at least a portion of the solvent generally improves the efficiency of subsequent processing steps and results in a purer finished extract.
In the settling step 1050 of the method 1000, a sediment of solid particles is precipitated from the concentrated crude oil by any suitable means, although settling step 1050 generally comprises allowing the crude oil to reside for a predetermined period in a settling vessel, such as a conical settling tank or inclined plate settler. In embodiments, the settling of the sediment may be aided by any one or more of the addition of a chemical (solid or liquid) separating agent, centrifugation, filtration, and so on. Generally, a first phase resulting from settling step 1050 is a cannabinoid- and/or terpene-rich phase (e.g., comprising at least most, and in embodiments at least 75%, of cannabinoids and/or terpenes in the concentrated crude oil, and having a low proportion of proteins, sugars, resin glues, chlorophyll, and/or lipids), and the second phase resulting from settling step 1050 is an impurity-rich phase (e.g., comprising at least most of the impurities in the concentrated crude oil and having a low proportion of substances of interest such as cannabinoids and/or terpenes); in embodiments, the impurities may include proteins, sugars, resin glues, chlorophyll, and/or lipids. Typically, the first and second phases may be substantially immiscible to facilitate further processing.
In the decarboxylation step 1060 of the method 1000, the cannabinoid- and/or terpene-rich phase formed in settling step 1050 is decarboxylated by heating at approximately atmospheric or ambient temperature to form a “winterized” cannabinoid and/or terpene oil. The cannabinoid- and/or terpene-rich phase may, but need not, be agitated or stirred during decarboxylation step 1060.
In the vacuum heating step 1070 of the method 1000, the “winterized” cannabinoid and/or terpene oil is heated at sub-atmospheric (in some embodiments, vacuum or near-vacuum) pressures to further degas, purify, and/or pre-treat the oil and thereby form a distillation-ready oil. In some embodiments, the vacuum heating step 1070 may comprise more than one vacuum heating sub-step (e.g., by varying a temperature or pressure), in a single vessel or in two or more separate vessels.
In short-path distillation step 1080, the distillation-ready oil is distilled at least once in at least one short-path distillation apparatus to produce a finished cannabinoid and/or terpene oil. The finished product of the method 1000 is a yellow-colored or golden cannabinoid and/or terpene oil of high purity and quality. In embodiments, cannabinoids may make up at least about 70 wt %, and preferably at least about 80 wt %, of the end product. In some embodiments, cannabidiol may make up at least about 70 wt %, and preferably at least about 80 wt %, of the end product.
The method 1000 may optionally include any one or more additional steps not illustrated in
In one non-limiting example, embodiments of the present invention are directed to a method for preparing a purified cannabis extract. The method may utilize any components or process equipment as described throughout the present disclosure.
The method may include, but is not limited to, a mixing and separation step, where plant material and solvent (e.g., ethanol) is mixed to form a slurry and then the slurry is separated into a solid residue and a raw extract (e.g., via centrifuging). The method may include, but is not limited to, a filtration step to remove solid plant material from the raw extract. The method may include, but is not limited to, a concentration or evaporation step to heat the raw extract to remove the solvent, leaving concentrated extract or crude oil. The method may include, but is not limited to, a condensing step to condense the evaporated solvent.
The method may include, but is not limited to, a static separating step to remove impurities such as waxes, chlorophyll, proteins, sugars from the crude oil via a settling unit. For example, the static separating step may occur a period of approximately eight hours.
The method may include, but is not limited to, mixing the concentrated extract with a brine solution and at least one acid. The method may include, but is not limited to, turning at least one additional impurity into a water-soluble electrolyte. The method may include, but is not limited to, washing the concentrated extract, brine solution, and at least one acid with water to remove at least a portion of the at least one additional impurity.
The method may include, but is not limited to, an atmospheric heating step or winterization step, where phosphoric acid and citric acid are added to the crude oil to remove impurities such as proteins, sugars, and lipids. For example, the atmospheric heating step may occur for a period of approximately three hours. It is noted brine may additionally be added where water is used to wash the impurities from the process equipment, as the brine may increase the density of the water and assist the floating of the separated crude oil on top of the water and above the impurities.
The method may include, but is not limited to, a vacuum heating step where the crude oil is heated to remove excess water and to create a decarboxylated oil or winterized oil. For example, the vacuum heating step may include temperatures up to approximately 90° C. It is noted the atmospheric heating step and the vacuum heating step may be considered a decarboxylation and degassing step requiring both an atmospheric heating vessel and a vacuum heating vessel.
The method may include, but is not limited to, a short-path distillation step configured to distill the decarboxylated oil to form a purified plant extract. The short-path distillation step may include a second vacuum heating step prior to a short filter in a short-path distillation unit. In addition, an additional tank may be used to separate compounds of interest such as cannabinoids, cannabidiol, and/or terpenes from the purified plant extract. It is noted dropping the vacuum to low enough pressures may be to not require high temperatures to separate the compounds of interest from the purified plant extract.
Embodiments of the present invention may suitably be used to extract any one or more cannabinoids from cannabis or other plant material. Cannabinoids amenable to extraction by embodiments of the present invention include, but are not limited to, cannabichromene-type (CBC) cannabinoids, e.g., (±)-cannabichromene (CBC-C5), (±)-cannabichromenic acid A (CBCA-C5 A), (±)-cannabichromevarin (CBCV-C3), and (±)-cannabichromevarinic acid A (CBCVA-C3 A); cannabichromanone-type (CBCN) cannabinoids, e.g., cannabichromanone (CBCN-C5), cannabichromanone-C3 (CBCN-C3), and cannabicoumaronone (CBCON-C5); cannabidiol-type (CBD) cannabinoids, e.g., (−)-cannabidiol (CBD-C5), cannabidiol monomethyl ether (CBDM-C5), cannabidiol-C4 (CBD-C4), (−)-cannabidivarin (CBDV-C3), cannabidiorcol (CBD-C1), cannabidiolic acid (CBDA-C5), and cannabidivarinic acid (CBDVA-C3); cannabielsoin-type (CBE) cannabinoids, e.g., (5aS,6S,9R,9aR)-cannabielsoin (CBE-C5), (5aS,6S,9R,9aR)-C3-cannabielsoin (CBE-C3), (5aS,6S,9R,9aR)-cannabielsoic acid A (CBEA-C5 A), (5aS,6S,9R,9aR)-cannabielsoic acid B (CBEA-C5 B), (5aS,6S,9R,9aR)-C3-cannabielsoic acid B (CBEA-C3 B), cannabiglendol-C3 (OH-iso-HHCV-C3), dehydrocannabifuran (DCBF-C5), and cannabifuran (CBF-C5); cannabigerol-type (CBG) cannabinoids, e.g., cannabigerol ((E)-CBG-C5), cannabigerol monomethyl ether ((E)-CBGM-C5 A), cannabinerolic acid A ((Z)-CBGA-C5 A), cannabigerovarin ((E)-CBGV-C3), cannabigerolic acid A ((E)-CBGA-C5 A), cannabigerolic acid A monomethyl ether ((E)-CBGAM-C5 A), and cannabigerovarinic acid A ((E)-CBGVA-C3 A); cannabicyclol-type (CBL) cannabinoids, e.g., (±)-(1aS,3aR,8bR,8cR)-cannabicyclol (CBL-C5), (±)-(1aS,3aR,8bR,8cR)-cannabicyclolic acid A (CBLA-C5 A), and (±)-(1aS,3aR,8bR,8cR)-cannabicyclovarin (CBLV-C3); cannabinol-type (CBN) cannabinoids, e.g., cannabinol (CBN-C5), cannabinol-C4 (CBN-C4), cannabivarin (CBN-C3), cannabinol-C2 (CBN-C2), cannabiorcol (CBN-C1), cannabinolic acid A (CBNA-C5 A), and cannabinol methyl ether (CBNM-C5); cannabinodiol-type (CBND) cannabinoids, e.g., cannabinodiol (CBND-C5) and cannabinodivarin (CBND-C3); cannabicitran-type or cannabitriol-type (CBT) cannabinoids, e.g., cannabicitran (CBT-C5), (−)-(9R,10R)-trans-cannabitriol ((—)-trans-CBT-C5), (+)-(9S,10S)-cannabitriol ((+)-trans-CBT-C5), (±)-(9R,10S19S,10R)-cannabitriol ((±)-cis-CBT-C5), (−)-(9R,10R)-trans-10-O-ethyl cannabitriol ((—)-trans-CBT-OEt-C5), (±)-(9R,10R/9S,10S)-cannabitriol-C3 ((±)-trans-CBT-C3), 8,9-dihydroxy-Δ6a(10a)-tetrahydrocannabinol (8,9-Di-OH-CBT-C5), cannabidiolic acid A cannabitriol ester (CBDA-C5 9-OH-CBT-C5 ester), cannabiripsol (cannabiripsol-C5), (—)-6a,7,10a-trihydroxy-Δ9-tetrahydrocannabinol ((−)-cannabitetrol), and 10-oxo-Δ6a(10a)-tetrahydrocannabinol (OTHC); isocannabinoids, e.g., (−)-Δ7-trans-(1R,3R,6r)-isotetrahydrocannabinol, (±)-Δ7-1,2-cis-(1R,3R,6S/1S,3S,6R)-isotetrahydrocannabivarin, and (−)-Δ7-trans-(1R,3R,6R)-isotetrahydrocannabivarin; and tetrahydrocannabinol-type (THC) cannabinoids, e.g., Δ9-tetrahydrocannabinol (Δ9-THC-C5), Δ9-tetrahydrocannabinol-C4 (Δ9-THC-C4), Δ9-tetrahydrocannabivarin (Δ9-THCV-C3), Δ9-tetrahydrocannabiorcol (Δ9-THCO-C1), Δ9-tetrahydrocannabinolic acid A (Δ9-THCA-C5 A), Δ9-tetrahydrocannabinolic acid B (Δ9-THCA-C5 B), Δ9-tetrahydrocannabinolic acid-C4 A and/or B (Δ9-THCA-C4 A and/or B), Δ9-tetrahydrocannabivarinic acid A (Δ9-THCVA-C3 A), Δ9-tetrahydrocannabiorcolic acid A and/or B (Δ9-THCOA-C1 A and/or B), (−)-Δ8-trans-(6aR,10aR)-Δ8-tetrahydrocannabinol (Δ8-THC-C5), (−)-Δ8-trans-(6aR,10aR)-tetrahydrocannabinolic acid A (Δ8-THCA-C5 A), and (−)-(6aS,10aR)-Δ9-tetrahydrocannabinol ((−)-cis-Δ9-THC-C5).
Embodiments of the present invention may suitably be used to extract any one or more terpenes and terpenoids from cannabis or other plant material. Terpenes and terpenoids amenable to extraction by embodiments of the present invention include, but are not limited to, endo-borneol; δ-carene; bornyl acetate; α-ylangene; α-copaene; aromadendrene; eremophilene; longifolene; β-guaiene; valencene; β-bisabolene; γ-cadinene; β-selinene; neophytadiene; ferruginol; aristolone; β-amyrin; oleanane; ketoursene; α-amyrin; iridoids; iridoid glycosides; steroids, e.g., campesterol, β-sitosterol, γ-sitosterol, stigmasterol, tocopherols, cholesterol, testosterone, cholecalciferol, and ecdysone; hemiterpenoids, e.g., isoprene, prenol, and isovaleric acid; acyclic monoterpenes, e.g., ocimene and myrcenes; monocyclic monoterpenes, e.g., limonene, terpinene, phellandrene, and umbellulone; bicyclic monoterpenes, e.g., pinene α, pinene β, camphene, thujene, sabinene, and carene; acyclic monoterpenoids, e.g., linalool, citronellal, citral, citronellol, geraniol, and geranyl pyrophosphate; monocyclic monoterpenoids, e.g., grapefruit mercaptan, menthol, p-cymene, thymol, perillyl alcohol, and carvacrol; bicyclic monoterpenoids, e.g., camphor, borneol, eucalyptol, halomon, and ascaridole; sesquiterpenoids, e.g., farnesyl pyrophosphate, artemisinin, and bisabolol; diterpenoids, e.g., geranylgeranyl pyrophosphate, gibberellin, retinol, retinal, phytol, taxol, forskolin, aphidicolin, and salvinorin A; sesterterpenoids, e.g., geranylfarnesol; non-steroidal triterpenoids, e.g., saponins, squalene, lanosterol, oleanolic acid, ursolic acid, betulinic acid, and moronic acid); sesquarterpenes and sesquarterpenoids, e.g., ferrugicadiol and tetraprenylcurcumene; carotenes, e.g., α-carotene, β-carotene, γ-carotene, δ-carotene, lycopene, neurosporene, phytofluene, and phytoene; xanthophylls, e.g., canthaxanthin, cryptoxanthin, zeaxanthin, astaxanthin, lutein, and rubixanthin; polyterpenoids; norisoprenoids, e.g., 3-oxo-α-ionol, 7,8-dihydroionone, and precursors thereto; and activated isoprenes, e.g., isopentenyl pyrophosphate (IPP), dimethylallyl pyrophosphate (DMAPP), and precursors thereto.
A number of variations and modifications of the disclosure can be used. It would be possible to provide for some features of the disclosure without providing others. Additionally and/or alternatively, it may be possible to vary or modify the order and/or sequence of method steps or system processing units relative to the embodiments specifically described herein. Such modifications and variations are expressly contemplated to be within the scope of the present disclosure.
Ranges have been discussed and used within the forgoing description. One skilled in the art would understand that any sub-range within the stated range would be suitable, as would any number or value within the broad range, without deviating from the invention. Additionally, where the meaning of the term “about” as used herein would not otherwise be apparent to one of ordinary skill in the art, the term “about” should be interpreted as meaning within plus or minus five percent of the stated value.
Although the present disclosure describes components and functions implemented in the aspects, embodiments, and/or configurations with reference to particular standards and protocols, the aspects, embodiments, and/or configurations are not limited to such standards and protocols. Other similar standards and protocols not mentioned herein are in existence and are considered to be included in the present disclosure. Moreover, the standards and protocols mentioned herein and other similar standards and protocols not mentioned herein are periodically superseded by faster or more effective equivalents having essentially the same functions. Such replacement standards and protocols having the same functions are considered equivalents included in the present disclosure.
The present disclosure, in various aspects, embodiments, and/or configurations, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various aspects, embodiments, configurations embodiments, subcombinations, and/or subsets thereof. Those of skill in the art will understand how to make and use the disclosed aspects, embodiments, and/or configurations after understanding the present disclosure. The present disclosure, in various aspects, embodiments, and/or configurations, includes providing devices and processes in the absence of items not depicted and/or described herein or in various aspects, embodiments, and/or configurations hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and/or reducing cost of implementation.
The foregoing discussion has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description, for example, various features of the disclosure are grouped together in one or more aspects, embodiments, and/or configurations for the purpose of streamlining the disclosure. The features of the aspects, embodiments, and/or configurations of the disclosure may be combined in alternate aspects, embodiments, and/or configurations other than those discussed above. This method of disclosure is not to be interpreted as reflecting an intention that the claims require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed aspect, embodiment, and/or configuration. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.
Moreover, though the description has included description of one or more aspects, embodiments, and/or configurations and certain variations and modifications, other variations, combinations, and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative aspects, embodiments, and/or configurations to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.
Any of the steps, functions, and operations discussed herein can be performed continuously and automatically.
This application is a continuation-in-part of and claims priority to U.S. patent application Ser. No. 16/932,300, filed Jul. 17, 2020, entitled “Systems and Methods for Cannabis CBD Extraction,” the entire disclosure of which is hereby expressly incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16932300 | Jul 2020 | US |
| Child | 17884547 | US |
