SEMI-AQUEOUS METHOD FOR EXTRACTING A SUBSTANCE
20220008839 · 2022-01-13
Assignee
Inventors
- David P. Jackson (Saugus, CA, US)
- Mackenzie A. Jackson (Saugus, CA, US)
- John J. Lee (Santa Clarita, CA, US)
Cpc classification
B01D11/0296
PERFORMING OPERATIONS; TRANSPORTING
A23V2002/00
HUMAN NECESSITIES
A61K2236/37
HUMAN NECESSITIES
B01D11/0476
PERFORMING OPERATIONS; TRANSPORTING
A23L33/105
HUMAN NECESSITIES
A61K2236/51
HUMAN NECESSITIES
G01N11/00
PHYSICS
B01D11/0257
PERFORMING OPERATIONS; TRANSPORTING
A61K2236/331
HUMAN NECESSITIES
C12H3/00
CHEMISTRY; METALLURGY
B01D2011/007
PERFORMING OPERATIONS; TRANSPORTING
A61K2236/53
HUMAN NECESSITIES
International classification
A23L33/105
HUMAN NECESSITIES
C12H3/00
CHEMISTRY; METALLURGY
Abstract
A semi-aqueous method for extracting a substance. The method involves combining a first liquid or solid substance containing an extract with a semi-aqueous solution containing a water-soluble or water-emulsifiable (WSWE) compound. Said WSWE compound selectively dissolves extract during a dense phase CO.sub.2 expansion and salting-out process, which is simultaneously co-extracted using said dense phase CO.sub.2, and desolvated to produce a CO.sub.2 salted-out solvent mixture containing extract. Said CO.sub.2 salted-out solvent mixture is treated using various secondary processes. The present invention is useful for producing extracts for use as additives in pharmaceuticals, nutraceuticals, cosmetics, beverages, or foods, and for quantitative analysis.
Claims
1. A semi-aqueous extraction method for recovering an extract from a substance, the steps comprising: a. Placing the substance into a pressure vessel; b. Adding a semi-aqueous solution, comprising a mixture of water and water-soluble or water-emulsifiable compound, to the pressure vessel; c. Pressurizing said semi-aqueous solution and the substance using dense phase CO.sub.2 to establish a tunable extraction system in the pressure vessel; d. Expanding and salting-out said tunable extraction system using said dense phase CO.sub.2 to produce a first separated phase, which comprises the water-soluble or water-emulsifiable compound containing the extract; and e. Simultaneously co-extracting said first separated phase into said dense phase CO.sub.2 to produce a second separated phase, which comprises a CO.sub.2 salted-out solvent mixture containing the extract.
2. The semi-aqueous extraction method of claim 1, wherein said substance comprises natural product, pomace, animal tissue, soil, sludge, slurry, potable water, alcoholic beverage, fermentation broth, industrial wastewater, fermented food, or water-based extractant.
3. The semi-aqueous extraction method of claim 1, wherein said extract comprises phytochemical, essential oil, polyphenol, fermented compound, fermented ethanol, ethanol-soluble compound, decarboxylated compound, psychoactive compound, terpenoid, cannabinoid, flavonoid, carboxylic acid, protein, oxygenated compound, organic compound, metalorganic compound, inorganic compound, chemical pollutant, or ionic compound.
4. The semi-aqueous extraction method of claim 1, wherein said water-soluble or water-emulsifiable compound comprises alcohol, polyol, ketone, ester, nitrile, ether, organosulfur compound, surfactant, emulsion, hydrotrope, or aqueous carbon dioxide.
5. The semi-aqueous extraction method of claim 1, wherein said dense phase CO.sub.2 comprises gaseous CO.sub.2, solid CO.sub.2, liquid CO.sub.2, or supercritical CO.sub.2.
6. The semi-aqueous extraction method of claim 1, wherein said dense phase CO.sub.2 is contacted with said tunable extraction system at a temperature between −40° C. and 300° C. and at a pressure between 1 atm and 340 atm.
7. The semi-aqueous extraction method of claim 1, wherein said dense phase CO.sub.2 is preferably contacted with said tunable extraction system at a temperature between −20° C. and 150° C. and a pressure between 5 atm and 150 atm.
8. The semi-aqueous extraction method of claim 1, wherein said CO.sub.2 salted-out solvent mixture comprises gaseous CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound; said CO.sub.2 salted-out solvent mixture comprises liquid CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound; or said CO.sub.2 salted-out solvent mixture comprises supercritical CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound.
9. The semi-aqueous extraction method of claim 1, wherein said CO.sub.2 salted-out solvent mixture is a water-soluble or water-emulsifiable-rich CO.sub.2 salted-out solvent mixture containing the extract and a dense phase CO.sub.2-rich CO.sub.2 salted-out solvent mixture containing the extract.
10. The semi-aqueous extraction method of claim 1, wherein a quantity of said water-soluble or water-emulsifiable compound contained in said tunable extraction system and Hansen Solubility Parameters of said water-soluble or water-emulsifiable compound contained in said tunable extraction system are calculated based on an amount of the extract to be extracted by said water-soluble or water-emulsifiable compound and Hansen Solubility Parameters of the extract to be extracted by said water-soluble or water-emulsifiable compound.
11. The semi-aqueous extraction method of claim 1, wherein a quantity of said dense phase CO.sub.2 and Hansen Solubility Parameters of said dense phase CO.sub.2 are calculated based on an amount of said water-soluble or water-emulsifiable compound containing the extract to be co-extracted by said dense phase CO.sub.2 and Hansen Solubility Parameters of said water-soluble or water-emulsifiable compound containing the extract to be co-extracted by said dense phase CO.sub.2.
12. The semi-aqueous extraction method of claim 1, wherein said tunable extraction system is mixed with additives comprising purified water, organic acid, organic salt, inorganic salt, surfactant, co-surfactant, enzyme, pH buffer, chelation agent, triacetin, or ozone.
13. The semi-aqueous extraction method of claim 1, wherein said water-soluble or water-emulsifiable compound contained in said tunable extraction system is selectively expanded and salted-out using CO.sub.2 pressure, CO.sub.2 temperature or CO.sub.2 volume.
14. The semi-aqueous extraction method of claim 1, wherein a concentration of said water-soluble or water-emulsifiable compound in said tunable extraction system or said CO.sub.2 salted-out solvent mixture is between 0.1% and 95% by volume.
15. The semi-aqueous extraction method of claim 1, wherein said CO.sub.2 salted-out solvent mixture is used in a secondary process comprising solid-liquid extraction process, liquid-liquid extraction process, analytical chemical process, desolvation process, ozonation process, fractionation process, or decarboxylation process.
16. The semi-aqueous extraction method of claim 15, wherein said desolvation process comprises utilizing gravity separation, phase separation, near-cryogenic phase separation, high pressure distillation, atmospheric distillation, vacuum distillation, membrane separation, gas flotation, or evaporation to form a desolvated CO.sub.2 salted-out solvent mixture, which comprises a water-soluble or water-emulsifiable compound containing the extract.
17. The semi-aqueous extraction method of claim 16, wherein an ozonated gas is bubbled through said desolvated CO.sub.2 salted-out solvent mixture to form an oxygenated extract.
18. The semi-aqueous extraction method of claim 17, wherein said ozonated gas has a concentration between 0.2 mg/hour and 15000 mg/hour of ozone gas at a temperature between minus 20 degrees C. and 30 degrees C., and a pressure of about 1 atm.
19. The semi-aqueous extraction method of claim 17, wherein the concentration of said oxygenated extract is monitored and controlled using a digital timer or a viscosity sensor.
20. The semi-aqueous extraction method of claim 15, wherein said analytical chemical process comprises analyzing the extract dissolved in said CO.sub.2 salted-out solvent mixture using UV-VIS spectrophotometry, fluorescence spectroscopy, Raman spectroscopy, gas chromatography, high-performance liquid chromatography, ion chromatography, liquid density analysis, or gravimetric analysis.
21. The semi-aqueous extraction method of claim 20, wherein said analytical chemical process is performed in-situ or ex-situ.
22. A semi-aqueous extraction method for recovering an extract from a natural product, the steps comprising: a. Placing the natural product containing the extract into a first pressure vessel; b. Adding a semi-aqueous solution, which comprises water and a water-soluble or water-emulsifiable compound, to the first pressure vessel; c. Pressurizing said semi-aqueous solution and natural product with dense phase CO.sub.2 to a pressure between 1 atm and 340 atm to establish a tunable extraction system within the first pressure vessel; d. Heating said tunable extraction system contained within the first pressure vessel to a temperature between 30° C. and 300° C. and maintaining temperature for a time between 5 minutes and 120 minutes to produce a heated water-based extractant containing water-soluble or water-emulsifiable compound and extract within the first pressure vessel; e. Cooling said heated water-based extractant to a temperature between −40° C. and 40° C. during transfer to a second pressure vessel; f. Expanding and salting-out said cooled water-based extractant within the second pressure vessel using dense phase CO.sub.2 to produce a first separated phase, which comprises water-soluble or water-emulsifiable compound containing the extract; g. Simultaneously co-extracting said first separated phase in the second pressure vessel with said dense phase CO.sub.2 to produce a second separated phase, which comprises a CO.sub.2 salted-out solvent mixture containing the extract; h. Transferring said CO.sub.2 salted-out solvent mixture containing the extract to a third pressure vessel; and i. Desolvating said CO.sub.2 salted-out solvent mixture within the third pressure vessel to concentrate and recover said extract.
23. The semi-aqueous extraction method of claim 22, wherein said natural product comprises plant, vegetable, fruit, nut, spice, herb, hops, root, bark, hemp, or cannabis.
24. The semi-aqueous extraction method of claim 22, wherein said extract is decarboxylated.
25. A semi-aqueous extraction method for forming an alcoholic mixture, the steps comprising: a. Placing a natural product containing an extract into a pressure vessel; b. Adding an alcoholic beverage containing fermented ethanol and ethanol-soluble fermented compounds to the pressure vessel; c. Pressurizing said alcoholic beverage and the natural product using dense phase CO.sub.2 to establish a tunable extraction system in the pressure vessel; d. Expanding and salting-out said tunable extraction system using said dense phase CO.sub.2 to produce a first separated phase, which comprises fermented ethanol, ethanol-soluble fermented compounds, and the extract; e. Simultaneously co-extracting said first separated phase using said dense phase CO.sub.2 to produce a second separated phase, which comprises a CO.sub.2 salted-out solvent mixture containing the fermented ethanol, the ethanol-soluble fermented compounds, and the extract; and f. Desolvating said CO.sub.2 salted-out solvent mixture to concentrate and to form the alcoholic mixture.
26. The semi-aqueous extraction method of claim 25, wherein said alcoholic beverage comprises beer, vodka, port, rum, gin, whiskey, bourbon, brandy, grain alcohol, cognac, tequila, wine, baijiu, sake, soju, hard seltzer, or hard cider.
27. The semi-aqueous extraction method of claim 25, wherein said alcoholic mixture is desolvated to form a non-alcoholic concentrate.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0076] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrates the present invention and, together with the description, serve to exemplify the principles, practices, benefits, and novelty of the present invention.
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DETAILED DESCRIPTION OF THE INVENTION
[0088] In the description that follows, like parts are indicated throughout the specification and drawings with the same reference numerals, respectively. The figures are not drawn to scale and the proportions of certain parts have been exaggerated for convenience of illustration.
[0089] The liquid-liquid phase separation phenomenon, which forms the basis of exemplary CO.sub.2 SALLE methods and apparatuses detailed herein, was unexpectedly observed by the first-named inventor during dense phase CO.sub.2-liquid solubility experiments employing a high pressure Jerguson Gage. In one experiment among many involving natural oils and alcohols, the Jerguson Gage was partially filled with an aqueous solution comprising 10% isopropanol (IPA) and 90% deionized water (H.sub.2O), considered a dilute aqueous alcoholic (DAA) solution. The purpose of this extraction test was to determine the volume of IPA that could be extracted from a substantially water-based solution (aqueous phase). IPA is a water-soluble or water emulsifiable (WSWE) organic compound useful for practicing the present invention. While applying an incremental and increasing CO.sub.2 gas pressure gradient over said aqueous solution ranging from 1 atm (ambient pressure, no CO.sub.2 gas present) to 61 atm (CO.sub.2 gas saturation conditions) at a temperature of approximately 20° C., an IPA phase was formed (visually evident) at 7 atm and gradually increased in volume above the aqueous phase as CO.sub.2 pressure increased. This phase separation was also marked by a gradual decrease in the level of the aqueous phase meniscus (or interphase). Additionally, the volume of the IPA phase decreased, and the volume of the aqueous phase increased as the CO.sub.2 gas pressure was decreased, but more slowly presumably due to IPA-water density differences and CO.sub.2 gas evolution (effervescence), demonstrating the capability to control the IPA-water phase separation process reversibly using CO.sub.2 gas pressure.
[0090] Further development determined that injecting solid-gas CO.sub.2 aerosol through the lower port of the Jerguson Gage using a small capillary tube significantly improved the liquid-liquid phase separation process through improved mixing action and lower solution temperature. Lower solution temperature increased CO.sub.2 solubility levels and the resulting CO.sub.2 froth rising through the aqueous solution quickly transferred and segregated the IPA solvent phase to form an upper surface layer. As such, this technique is a preferred CO.sub.2 injection method in the present invention. Upon reaching CO.sub.2 gas saturation conditions (>54 atm at 20° C.), a water-insoluble liquid CO.sub.2 phase was formed above the aqueous solution and the IPA phase. Following this, a portion of the IPA solvent phase diffused and dissolved into the liquid CO.sub.2 phase, indicating that the small amount of liquid CO.sub.2 phase quickly reached a saturation condition with the IPA phase. As more liquid CO.sub.2 was added to the Jerguson Gage, more IPA dissolved into the liquid CO.sub.2 phase.
[0091] Subsequently, IPA dissolved in the liquid CO.sub.2 was recovered by withdrawing the upper liquid CO.sub.2 phase and condensing same into a solid phase CO.sub.2-IPA mixture using a 6-foot section of 0.020-inch (inside diameter) polyetheretherketone (PEEK) capillary tubing. The PEEK capillary condenser technique is a simple CO.sub.2 condensation process developed by the first-named inventor in the early 1990's, described in prior art U.S. Pat. No. '154 et al., and is uniquely adapted to the present invention as a novel near-cryogenic phase separation and extract recovery technique.
[0092] Moreover, testing with dilute and concentrated acetone-water solutions produced similar results as IPA-water solutions. Still moreover, additional testing confirmed that the CO.sub.2 SALLE process was very effective in separating and recovering fermented and distilled ethanol (and Raspberry flavonoids) from a commercially available Raspberry-flavored 70 Proof Vodka (35% fermented EtOH by volume), as well as ethanol (and Whiskey flavonoids) from a commercially available 80 Proof Bourbon Whiskey (40% fermented EtOH by volume). Flavonoids represent a complex mixture of polyphenolic compounds which are not appreciably soluble in nonpolar solvents such as liquid and supercritical carbon dioxide.
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[0094] Experiments were performed by the present inventors using a high pressure Jerguson Gage (Series 40, Transparent Rectangular Sight Glass, 5000 psi @ 100° F. rating, Clark-Reliance, Strongsville, Ohio). The Jerguson Gage contains threaded top and bottom ports for implementing piping, pressure Gage, and inlet-outlet valves for facilitating filling, pressurization, and draining test solvents and CO.sub.2 gas. The Jerguson Gage was filled with a fixed volume (about 50% of Gage capacity) of aqueous solvent solution comprising 90%:10% (by volume) Water:IPA, also described as a dilute aqueous alcohol (DAA) solution herein, following which pressure-regulated CO.sub.2 gas derived from a steel cylinder of high pressure liquid CO.sub.2 was introduced into the top of the Jerguson Gage containing said fixed volume of aqueous organic solvent in discrete and increasing pressurization increments or stages from 1 atm to 61 atm. Prior to and following each pressurization stage, a fixed-position digital camera was used to take a photograph of the same liquid-vapor level region within the Jerguson Gage, supplemented by low-level backlight illumination using a microscope light source positioned behind the transparent high-pressure window of the Jerguson Gage.
[0095] Now referring to
TABLE-US-00003 TABLE 3 CO.sub.2 Pressure vs. Density (Concentration) @ T = 20° C. Pressure P.sub.CO2 - Density atm σ - g/cm.sup.3 1 0.002 7 0.013 14 0.027 20 0.041 27 0.058 34 0.078 41 0.101 48 0.131 54 0.166 61 0.787
[0096] The IPA phase (an exemplary WSWE compound) is expanded and salted-out to the surface of the Water:IPA solution due to both density and solubility parameter (cohesion energy) differences. The IPA phase increases in volume during CO.sub.2 expansion and as more CO.sub.2-based species are formed within the semi-aqueous solution. Finally, the emergent IPA phase is (selectively) dissolved into a liquid carbon dioxide phase formed at a CO.sub.2 pressure above 54 atm, evidenced by the appearance of the liquid CO.sub.2 interphase at level C (6). Again, referring to
[0097] a) Aqueous CO.sub.2 (CO.sub.2(aq) Phase (10)
[0098] b) CO.sub.2 Expanded IPA Phase (12); and
[0099] c) Saturated Liquid CO.sub.2-IPA Phase (8)
[0100] The aqueous CO.sub.2 phase (δ.sub.T—47.8 MPa.sup.1/2) forms a lower phase with a interphase at level B (4), salting-out the CO.sub.2 Expanded IPA Phase (δ.sub.T˜23.6 MPa.sup.1/2) to the surface due to an approximate 20% difference in density (water—1.0 g/cm.sup.3 and IPA—0.78 g/cm.sup.3 with a interphase at level A (2), and forms a saturated liquid CO.sub.2-IPA upper phase (δ.sub.T˜20 MPa.sup.1/2) at 61 atm with a interphase at level C (6).
[0101] Finally, and again referring to
[0102] Now referring to
[0103] Finally, interfacial turbulence caused by Marangoni-Rayleigh instability during the physical absorption and desorption of carbon dioxide into and from non-aqueous solvents (i.e., WSWE compounds) salted-out from a semi-aqueous solution. Marangoni instabilities depend on the change of interfacial tension and Rayleigh instabilities on the change of liquid densities with solute concentration. Such flows develop increasingly complex cellular or wavy patterns. The presence of interfacial turbulence significantly enhances mass transfer rates in liquid-liquid and solid-liquid extraction processes.
[0104] The observed Marangoni-Rayleigh convections (turbulences) observed in the CO.sub.2 SALLE process are due to differences in interfacial surface tensions and densities, but visible and unique (microscopic or macroscopic) pattern formations within the interphases, as evidenced by light transmission changes from transparent to translucent, are presumably due to cohesion energy differences between the CO.sub.2, WSWE solutes, water, and gravity. As such, combined with the observations of Sun et al., it can be conjectured that the visible interfacial turbulences described herein under
[0105] Having discussed CO.sub.2 salting-out behavior of the exemplary CO.sub.2 SALLE process, following is a more detailed discussion of CO.sub.2 solubility and acidification aspects under
[0106] The IPA salting-out effects described under
[0107] Water content levels in semi-aqueous solutions containing organic solvents such as alcohols (i.e., ethanol, methanol, IPA) can significantly impact botanical extraction performance, and particularly at lower solution temperatures and for recovery of relatively nonpolar botanical compounds such as terpenes and cannabinoids. Degradation of extraction performance is attributed to unfavorable changes in chemical and physical factors such as increased cohesion energy (i.e., lower solubility of organic compounds) and increased surface tension (i.e., poor wetting of botanical surfaces). Semi-aqueous compositions of the present invention can range between 0.1% and 95% WSWE content, and preferably between 0.1% and 30% WSWE compounds by volume. As such, the majority component of exemplary semi-aqueous compositions of the present invention is water. In this regard, the present invention uniquely enables the use of water-concentrated semi-aqueous solutions as effective biphasic and multiphasic extractants for botanical compounds possessing extremely limited water solubility (i.e., nonpolar terpenoids) and organic compounds exhibiting higher water solubility (i.e., polar flavonoids).
[0108] Moreover, exemplary CO.sub.2 SALLE processes of the present invention can be operated at lower temperatures and higher pressures, enabled by a near-cryogenic CO.sub.2 gas-solid aerosol to produce CO.sub.2 saturation with lower solution temperature in combination with (preferably) elevated CO.sub.2 pressures using autogenous or mechanical pressurization. In this regard,
[0109] Also, liquid phase water is only sparingly soluble (as a solute) in liquid CO.sub.2. However, CO.sub.2 (as a hydrated and ionized solute, and dissolved gas) is variably soluble within a semi-aqueous solution based on both CO.sub.2 pressure (P) and temperature (T), as well as WSWE compound composition. At P-T operating ranges employed in the present invention, significant differences exist between the aqueous phase and dense phase CO.sub.2 in terms of density (σ) and total Hansen Solubility Parameter (δ.sub.T). For example, at 80 atm and 0° C., liquid CO.sub.2 has a σ=0.96 g/ml and a δ.sub.T=17.9 MPa.sup.1/2 and liquid water has a σ=1 g/ml and a δ.sub.T=47.9 MPa.sup.1/2. As CO.sub.2 gas is compressed into an aqueous solution at a pressure greater than approximately 54 atm at room temperature a water-insoluble liquid CO.sub.2 phase forms above the aqueous solution.
[0110] Simultaneously with this, and in accordance with Equation 1 (Eq. 1), a P-T controlled portion of the CO.sub.2 dissolves (as a gas) into said aqueous solution to form hydrated and ionized CO.sub.2 species: P-T adjustable amounts of dissolved carbonic acid (H.sub.2CO.sub.3), bicarbonate anion (HCO.sub.3.sup.−), and carbonate anion (CO.sub.3.sup.2−), collectively referred to herein as aqueous CO.sub.2 or CO.sub.2 (aq).
CO.sub.2+H.sub.2O.Math.H.sub.2CO.sub.3.Math.HCO.sub.3.sup.−+H.sup.+.Math.CO.sub.3.sup.2−+2H.sup.+ (Eq. 1)
[0111] In the present invention, CO.sub.2 (aq) is uniquely employed to complex water molecules to assist CO.sub.2 expansion with selectively salting-out WSWE and solvent-soluble compounds (i.e., extracts) dissolved in a semi-aqueous solution. As described herein with respect to Eq. 1, this is a result of the hydration of CO.sub.2 gas molecules and the formation of carbonic acid, believed to be one of the major drivers of the CO.sub.2 SALLE process at elevated pressures, and subsequent ionization of carbonic acid to form bicarbonate and carbonate anions. CO.sub.2 (aq) species are very stable, even at high temperature. However, the concentration and stability of hydrated CO.sub.2 (aq) complexes are CO.sub.2 pressure and solution temperature dependent.
[0112] In Garand, E. et al., “Infrared Spectroscopy of Hydrated Bicarbonate Anion Clusters: HCO.sub.3—(H.sub.2O).sub.1-10”, J. AM. CHEM. SOC. 2010, 132, 849-856 (Garand et al.), spectroscopic evidence was presented that showed water molecules strongly associate and complex with the negatively charged CO.sub.2 moiety of the HCO.sub.3.sup.− anion. The most stable isomer comprises n=4 water molecules, a four-membered ring with each water molecule forming a single H-bond with the CO.sub.2 moiety. A second hydration shell forms at n=6 water molecules and forms a total hydration shell comprising ten (10) water molecules. Further to this, in Zilberg, S., et al., “Carbonate and Carbonate Anion Radicals in Aqueous Solutions Exist as CO.sub.3(H.sub.2O).sub.6.sup.2− and CO.sub.3(H.sub.2O).sub.6.sup.− Respectively: The Crucial Role of the Inner Hydration Sphere of Anions in Explaining Their Properties”, Phys. Chem. Phys. Chem., 2018, 20, 9429-9435 (Zilberg et al.), spectroscopic evidence was presented demonstrating that the carbonate anion radicals form strong six (6) member hydration shells. Finally, in Wu, G. et al., “Temperature Dependence of Carbonate Radical in NaHCO.sub.3 and Na.sub.2CO.sub.3 Solutions: Is the Radical a Single Anion?”, J. Phys. Chem. A, 2002, 106, 2430-2437 (Wu et al.), Wu et al. determined that carbonate and bicarbonate anions dissolved in supercritical water are very stable. Wu et al. used pulsed radiolysis to produce and measure carbonate radical concentrations formed from these supercritical water-salt solutions and showed no appreciable change in the carbonate-bicarbonate anion system at temperatures as high as 400° C.
[0113] Moreover, with an increasing concentration of CO.sub.2 (aq), the pH of an (unbuffered) aqueous solution decreases. As such, small amounts of associated water co-extracted with a WSWE compound and solubilized into either an aqueous or dense phase CO.sub.2 extraction solvent phase will be weakly acidic due to the presence of excess carbonic acid at high CO.sub.2 gas saturation. In Peng, C. et al., “The pH of CO.sub.2-saturated Water at Temperatures between 308 K and 423 K at Pressures up to 15 MPa”, J. of Supercritical Fluids 82 (2013) 129-137 (Peng et al.), it was determined that pH was dependent upon temperature, pressure, and CO.sub.2 gas solubility in water (H.sub.2O) at temperatures between 308 K (35° C.) and 423 K (150° C.) and pressure up to 15 MPa (148 atm, 2175 psi). For the pH measurements, liquid CO.sub.2 was selectively pressurized into a temperature-controlled water sample using a precision syringe pump (Teledyne Isco, Model 100DM). The CO.sub.2+H.sub.2O system was contained in a pressure vessel outfitted with pressure, temperature, and pH sensors. The results of this study showed that pH decreases along an isotherm in proportion to −log 10(x), where x is the mole fraction of dissolved CO.sub.2 in H.sub.2O. The pH for the CO.sub.2+H.sub.2O system at 35° C. ranged from about pH=3.8 to pH=3 between 60 psi and 2000 psi. As expected, increasing temperature reduced CO.sub.2 gas solubility, which increased pH values. The pH for the CO.sub.2+H.sub.2O system at 150° C. ranged from about pH=4.0 to pH=3.5 between 145 psi and 2000 psi.
[0114] Processing (salting-out) temperatures for exemplary CO.sub.2 SALLE methods of the present invention are preferably less than 30° C. to produce a liquid CO.sub.2 phase above the semi-aqueous solution. As such, the pH range at these operating temperatures (at elevated pressures) is estimated to be between pH=3.5 and pH=2 due to the much higher CO.sub.2 gas solubility levels. In the present invention, this aspect is beneficial for improving the extraction performance of natural products containing target compounds with functional groups behaving as acids or bases, for example CBDA and THCA extracts found in cannabis. For example, in Heydari, R. et al., “Simultaneous Determination of Saccharine, Caffeine, Salicylic acid and Benzoic acid in Different Matrixes by Salt and Air-assisted Homogeneous Liquid-Liquid Extraction and High-Performance Liquid Chromatography”, J. Chil. Chem. Soc., 61, No. 3, 2016 (Heydari et al.), it was determined that sample pH has a significant influence on the extraction efficiency of organic extracts with acidic or basic functional groups and that the optimal extraction efficiency occurs at a pH=3.
[0115] In the present invention, CO.sub.2 (aq) demonstrates strong and selective salting-out behavior in aqueous solutions containing WSWE compounds. For example, dissolved organic compounds (i.e., fermented ethanol (EtOH) and EtOH-soluble compounds) are adjustably “salted-out” from aqueous solutions using pressure- and temperature-controlled concentrations of CO.sub.2 (aq). The amount of salted-out organic solvent is directly proportional to the concentration of CO.sub.2 (aq). Moreover, injecting CO.sub.2 into the bottom of an aqueous phase containing a WSWE compound produces turbulence and cooling actions through CO.sub.2 solid phase sublimation and Joule-Thomson expansion effects, which enhances CO.sub.2 gas saturation and mixing during salting-out of the organic solvent(s). Turbulence enhances transfer of organic compounds into the salted-out organic solvent phase and assists the rise and separation of the salted-out solvent phase (and solvent-soluble compounds) to the surface of the aqueous solution as the CO.sub.2 rises, a process called dissolved gas flotation.
[0116] The CO.sub.2 SALLE process can be operated at elevated temperatures and pressures, for example above the critical point for pure CO.sub.2 (Tc=31° C., Pc=73 atm). This aspect is useful for performing hybrid subcritical water-CO.sub.2 SALLE extraction processes described herein utilizing pressurized and heated water-based extraction solvents, for example using hydroethanolic mixtures to extract a solid substance at 80° C. in a subcritical water extraction process. Higher aqueous solution temperatures require higher dense phase CO.sub.2 pressures to produce efficient and effective expansion and salting-out effects. Moreover, using semi-aqueous solutions containing WSWE compounds such as surfactants at temperatures above their surfactant cloud point temperature (T.sub.c) can cause the surfactants to prematurely separate from the aqueous solution prior to the CO.sub.2 SALLE process. This can affect the performance of the extraction process and complicate follow-on desolvation and extract recovery processes. As such, semi-aqueous extraction solutions are preferably cooled to below 50° C. prior to adding WSWE compounds such as these to maximize CO.sub.2 expansion, ionization, and hydration effects, and to minimize complications during the CO.sub.2 SALLE process. For example, a subcritical water extractant operating at 100° C. may be first cooled using a conventional heat exchanger and then further cooled and saturated with CO.sub.2 using the novel near-cryogenic CO.sub.2 solid-gas aerosol injection process described under
[0117] Subsequently, CO.sub.2 salted-out WSWE compounds containing solubilized extracts (also collectively referred to as CO.sub.2 salted-out compounds) may be withdrawn as a CO.sub.2 gas pressurized and carbonated solvent phase from the top-layer of the aqueous solution. Alternatively, CO.sub.2 salted-out compounds (i.e., solvents, surfactants, and extracts) may be solubilized (partially or completely) within a top-layer liquid (or supercritical) CO.sub.2 phase and used as solvent blend for an extraction process or desolvated to recover the CO.sub.2 and CO.sub.2-salted-out compounds. In an exemplary separation process of the present invention, CO.sub.2 salted-out organics and liquid CO.sub.2 are first separated from the top-layer of the aqueous phase and then phase-separated or desolvated using a near-cryogenic (−78° C.) crystallization process. Other novel CO.sub.2 SALLE methods discussed herein include an in-situ aqueous botanical solid extraction and extracted oil flotation process. Finally, the CO.sub.2 salted-out organic compounds (extracts) may be analyzed using an in-situ analytical chemical process such as light-induced fluorescence or injected directly into an external analytical chemical process instrument such as a high-performance liquid chromatography system or liquid density measurement system.
[0118] Having discussed exemplary aspects of phase separation phenomenon related to aqueous CO.sub.2 solubility behavior under
[0119]
[0120] A central aspect of the CO.sub.2 SALLE process is the use of CO.sub.2 pressure and semi-aqueous solution temperature to selectively salt-out one or more WSWE compounds dissolved in a semi-aqueous solution to provide a biphasic or multiphasic extractant before, during, or after a liquid-liquid or solid-liquid extraction process. Further to this, in experiments employing either dilute or concentrated semi-aqueous solutions, light transmission through the fluid as viewed in the Jerguson Gage window changes from a transparent fluid to a translucent fluid with the introduction of CO.sub.2 gas, indicating the development of one or more solvent interphases and the onset of so-called Marangoni-Rayleigh turbulence driven by surface tension and density gradients between the visible interphases (mass transfer interfaces).
[0121] In Sun, Z. et al., “Absorption and Desorption of Carbon Dioxide into and from Organic Solvents: Effects of Rayleigh and Marangoni Instability”, Ind. Eng. Chem. Res. 2002, 41, 1905-1913 (Sun et al.), Sun et al. describe interphase surface patterns created by Marangoni-Rayleigh convection (or turbulence) during absorption and desorption of CO.sub.2 into and from several organic solvents. The research of Sun et al. showed that CO.sub.2 absorbing or desorbing from the different organic solvents creates unique high surface area and turbulent roll or polygonal cellular surface structures as evidenced by Schilieren interference pattern imaging. Moreover, Sun et al. showed that CO.sub.2 absorbing into water produced no interfacial turbulence, and the absorption process is laminar and controlled by the liquid-phase resistance according to penetration theory (CO.sub.2 Gas Phase.fwdarw.CO.sub.2-Water Interface.fwdarw.Liquid Water Phase).
[0122] Now referring to
[0123] Finally, unique physicochemical changes in semi-aqueous compositions shown and described under
[0124] In this regard, in Stone, H. W., “Solubility of Water in Liquid Carbon Dioxide”, Ind. Eng. Chem., 1943, 35, 12, pp. 1284-1286 (Stone), Stone experimentally determined the solubility of water (as a solute) in liquid carbon dioxide (as a solvent) at a pressure between 15 atm and 60 atm and a temperature between (minus) −29° C. and 26.6° C. to range between 0.02% (v:v) and 0.10% (v:v). Stone's liquid CO.sub.2-water solubility results comport with the Jerguson Gage observations described under
[0125] In summary, based on the experimental observations, results, and analysis provided under
[0126] Having described exemplary CO.sub.2 SALLE phenomenon under
[0127]
[0131] Again, referring to
[0132] Still referring to
[0133] Referring to
[0134] Still moreover, said CO.sub.2 SALLE pressure vessel (96) may contain a quick-opening closure (not shown) for conveniently introducing and removing a solid material, for example biomaterials contained in a semi-permeable bag, cellulose or glass thimble, or basket, and used to perform in-situ and simultaneous solid-liquid extraction plus CO.sub.2 SALLE extract concentration, desolvation, and recovery processes of the present invention.
[0135] Finally, the exemplary CO.sub.2 SALLE apparatus described under
[0136] Operational aspects of the exemplary CO.sub.2 SALLE apparatus and process described in
[0137] Now referring to
[0138] A monophasic extraction system (156) employs a semi-aqueous solution (158), containing for example water, one or more WSWE compounds, and optional additives, in a nitrogen (N.sub.2(g)) or a CO.sub.2 (g) atmosphere (160). The monophasic extraction system (156) is operated at an exemplary semi-aqueous solution temperature between 30° C. and 300° C. and an exemplary N.sub.2 (g) or CO.sub.2 (g) pressure between 5 atm and 85 atm. N.sub.2 (g) pressure is used to provide an inert vapor pressure at elevated temperatures to prevent solution boiling. Moreover, N.sub.2 (g) does not expand dissolved WSWE compounds (if present) and does not produce aqueous species in water. As such, N.sub.2 (g) is used in a WSWE-modified subcritical water extraction process to provide a monophasic WSWE-infused extraction chemistry. By contrast, CO.sub.2 (g) is used in several different ways: 1) provides a vapor pressure to prevent solution boiling, 2) lowers the pH of a semi-aqueous solution (even at low CO.sub.2 pressures (concentrations), and 3) selectively produces biphasic and multiphasic semi-aqueous extraction solutions. The monophasic extraction system (156) of the present invention is essentially a heated pressurized water or modified subcritical water extraction (MSWE) system, which produces a water-based extractant that is further processed using the CO.sub.2 SALLE process to concentrate, desolvate, and recover dissolved extracts contained therein. The MSWE system provides a monophasic extraction solvent system with a Hansen Solubility Parameter (HSP) ranging between about 47.8 MPa.sup.1/2 and 25 MPa.sup.1/2, depending upon the temperature and composition of the semi-aqueous solution. Finally, the MSWE system is preferably a mixed (intensified) system (162) comprising, for example, a mixing blade, ultrasonic homogenizer, or centrifuge drum. A mixing means (162) is preferably employed during a liquid-liquid or solid-liquid extraction process to enhance mass transfer.
[0139] Still referring to
[0140] Still referring to
[0141] Finally, with reference to
[0142] Looking at
[0143] An exemplary semi-aqueous extraction method for forming an alcoholic mixture containing an extract comprises: a semi-aqueous extraction method for forming an alcoholic mixture, the steps comprising: [0144] 1. Placing a natural product containing an extract into a pressure vessel (
[0150] Wherein said alcoholic beverage comprises beer, vodka, port, rum, gin, whiskey, bourbon, brandy, grain alcohol, cognac, tequila, wine, baijiu, sake, soju, hard seltzer, or hard cider; and said alcoholic mixture is desolvated to form a non-alcoholic concentrate.
[0151] The alcoholic mixture may be desolvated using, for example, vacuum distillation to remove fermented ethanol, which leaves a healthy and flavorful non-alcoholic beverage extract or concentrate. The non-alcoholic beverage extract can be added directly to foods and beverages or formulated into an emulsion to form a water-soluble composition.
[0152] In summary, the monophasic, biphasic, and multiphasic CO.sub.2 SALLE process used in a tunable extraction system as described under
[0153] A semi-aqueous extraction method for recovering an extract from a substance, the steps comprising: [0154] 1. Placing the substance into a pressure vessel (
[0159] Wherein said substance comprises natural product, pomace, animal tissue, soil, sludge, slurry, potable water, alcoholic beverage, fermentation broth, industrial wastewater, fermented food, or water-based extractant; said extract comprises phytochemical, essential oil, polyphenol, fermented compound, fermented ethanol, ethanol-soluble compound, decarboxylated compound, psychoactive compound, terpenoid, cannabinoid, flavonoid, carboxylic acid, protein, oxygenated compound, organic compound, metalorganic compound, inorganic compound, chemical pollutant, or ionic compound; said water-soluble or water-emulsifiable compound comprises alcohol, polyol, ketone, ester, nitrile, ether, organosulfur compound, surfactant, emulsion, hydrotrope, or aqueous carbon dioxide; said dense phase CO.sub.2 comprises gaseous CO.sub.2, solid CO.sub.2, liquid CO.sub.2, or supercritical CO.sub.2; said dense phase CO.sub.2 is contacted with said tunable extraction system at a temperature between −40° C. and 300° C. and at a pressure between 1 atm and 340 atm; said dense phase CO.sub.2 is preferably contacted with said tunable extraction system at a temperature between −20° C. and 150° C. and a pressure between 5 atm and 150 atm; said CO.sub.2 salted-out solvent mixture comprises gaseous CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound, liquid CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound, or supercritical CO.sub.2 and CO.sub.2 expanded and salted-out water-soluble or water-emulsifiable compound; said CO.sub.2 salted-out solvent mixture is a water-soluble or water-emulsifiable-rich CO.sub.2 salted-out solvent mixture containing the extract and a dense phase CO.sub.2-rich CO.sub.2 salted-out solvent mixture containing the extract; a quantity and Hansen Solubility Parameters of said water-soluble or water-emulsifiable compound contained in said tunable extraction system are calculated based on an amount and Hansen Solubility Parameters of the extract to be extracted by said water-soluble or water-emulsifiable compound; a quantity and Hansen Solubility Parameters of said dense phase CO.sub.2 are calculated based on an amount and Hansen Solubility Parameters of said water-soluble or water-emulsifiable compound containing the extract to be co-extracted by said dense phase CO.sub.2; said tunable extraction system is mixed with additives comprising purified water, organic acid, organic salt, inorganic salt, surfactant, co-surfactant, enzyme, pH buffer, chelation agent, triacetin, or ozone; said water-soluble or water-emulsifiable compound contained in said tunable extraction system is selectively expanded and salted-out using CO.sub.2 pressure, CO.sub.2 temperature, and CO.sub.2 volume; a concentration of said water-soluble or water-emulsifiable compound in said tunable extraction system or said CO.sub.2 salted-out solvent mixture is between 0.1% and 95% by volume; said CO.sub.2 salted-out solvent mixture is used in a secondary process comprising solid-liquid extraction process, liquid-liquid extraction process, analytical chemical process, desolvation process, ozonation process, fractionation process, or decarboxylation process; said desolvation process comprises utilizing gravity separation, phase separation, near-cryogenic phase separation, high pressure distillation, atmospheric distillation, vacuum distillation, membrane separation, gas flotation, or evaporation to form a desolvated CO.sub.2 salted-out solvent mixture, which comprises a water-soluble or water-emulsifiable compound containing the extract; an ozonated gas is bubbled through said desolvated CO.sub.2 salted-out solvent mixture to form an oxygenated extract; said ozonated gas has a concentration between 0.2 mg/hour and 15000 mg/hour of ozone gas at a temperature between minus 20 degrees C. and 30 degrees C., and a pressure of about 1 atm; the concentration of said oxygenated extract is monitored and controlled using a digital timer or a viscosity sensor; said analytical chemical process comprises analyzing the extract dissolved in said CO.sub.2 salted-out solvent mixture using UV-VIS spectrophotometry, fluorescence spectroscopy, Raman spectroscopy, gas chromatography, high-performance liquid chromatography, ion chromatography, liquid density analysis, or gravimetric analysis; and Said analytical chemical process is performed in-situ or ex-situ.
[0160] Having described the exemplary apparatus and tunable extraction system under
[0161] The present invention is useful in a variety of liquid-liquid and solid-liquid extraction applications. However, biomaterials such as herbs and spices present a unique set of solvent extraction process challenges. Example challenges include extraction solvent access to plant materials, extraction solvent solubility characteristics, and mass transfer characteristics for the vast range of plants and phytochemicals. A particular herb or spice contains a significant variety of phytochemicals. These phytochemicals possess different polarities, densities, molecular structures and complexities, molecular weights, states of matter (liquid or solid), and concentration. Moreover, phytochemicals are located and concentrated in different locations and structures of the plant, for example leaves, bark, membranes, roots, seeds, and flowers. In some extraction applications, for example cannabis and hemp, target phytochemicals such as terpenoids and cannabinoids are concentrated in glandular structures called trichomes, which are located on the leaves and flowers of these plant systems. In this regard, hemp and cannabis extractions are straightforward using a monophasic solvent system such as hexane, carbon dioxide, or ethanol, among many other solvents. However, other types of herb and spice extraction applications involve phytochemicals such as highly polar polyphenols which are located inside cellular structures encased by cutaneous, cellulosic, and other water-bearing structures, for example as present in fruit and vegetable pomaces. These water-bearing structures are barriers to mass transfer. Extraction and recovery of these types of phytochemicals is much more challenging and requires longer processing times, higher processing temperatures, and newer tunable solvent extraction processes such as subcritical water extraction. Given this, and as discussed herein, the present invention provides a tunable extraction system, and is particularly directed to biomaterial extraction applications involving substances such as herbs, spices, pomaces, among many other botanical examples.
[0162] A key process variable in botanical extractions is the optimization of both solvent penetration into plant structures, and solvation of organic compounds contained within these structures (i.e., solvent cohesion energy (solubility) characteristics and temperature). If the target compound (i.e., lycopene) is contained within a plant structure (i.e., tomato skin), mixed-polarity solvent blends are needed for swelling the plant structure to improve both solvent penetration and extract solvation processes. This is best understood by the following discussion regarding the physicochemical characteristics of plant surfaces and solvent blends used to optimize extraction of organic components from same.
[0163] According to Khayet, M. et al., “Estimation of the Solubility Parameters of Model Plant Surfaces and Agrochemicals: A Valuable Tool for Understanding Plant Surface Interactions”, Theoretical Biology and Medical Modelling 2012, 9:45 and Khayet, M. et al., “Evaluation of the Surface Free Energy of Plant Surfaces: Toward Standardizing the Procedure”, Frontiers in Plant Science, 1 Jul. 2015, Volume 6, Article 510 (Khayet et. al.), plant surfaces are a complex system. For example, the cuticle is made of a bio-polymer matrix, waxes that are deposited on to (epicuticular) or intruded into (intracuticular) this matrix, and variable amounts of polysaccharides and phenolics. Waxes commonly constitute 20 to 60% of the cuticle mass and are complex mixtures of straight chain aliphatics. The cuticle matrix is commonly made of cutin, which is a biopolymer formed by a network of inter-esterified, hydroxyl- and hydroxy-epoxy C16 and/or C18 fatty acids. Further to this, the cuticle acts as a “solution-diffusion” membrane for the diffusion of some solvents and solutes.
[0164] The total surface free energies of plant surfaces are diverse. For example, peach and pepper fruits have similar surface free energies (SFE), approximately 32.2 mN/m, but are significantly higher than that measured for Eucalyptus leaves, 17.4 mN/m. Concerning solubility parameters, Eucalyptus leaves exhibit a significantly lower value, 10.6 MPa.sup.1/2, than pepper and peach fruit surfaces, 17 MPa.sup.1/2. The dominant class of compounds in both pepper and peach fruit waxes is n-alkanes, which have a solubility parameter around 16 MPa.sup.1/2 for the most abundant compounds reported (C23 to C31 n-alkanes).
[0165] Given this, it is understood that the botanical system represents a complex extraction environment, with variable plant substances and surfaces having different SFE and solubility parameters. Moreover, according to Khayet et al., a solubility parameter gradient is established from the external and more hydrophobic epicuticular wax layer towards the more hydrophilic internal cell wall. Owing to the properties of the dominant epicuticular waxes present in the analyzed plant materials, it is concluded that the solubility parameter increases with increasing depth from the epicuticular wax surface towards the internal cell wall.
[0166] In this regard, it is understood that an optimal solvent chemistry is necessary, as well as mechanical and thermal optimizations, which provides both polar and nonpolar cohesion energies necessary to extract nonpolar lycopene located within polar cellulosic tissues of plants (i.e., tomato skins). Swelling the cellulosic structures is an important process variable during solvent extraction. A mixed-polarity solvent is required to provide cellulosic swelling, solvent penetration, and solvation of lycopene. As such, homogeneous solvent mixtures should be used that exhibit two distinct properties: (a) high lycopene affinity and (b) ability to swell the plant material and thus enhance solvent penetration and solvation phenomenon.
[0167] According to Zuorro, A., “Enhanced Lycopene Extraction from Tomato Peels by Optimized Mixed-Polarity Solvent Mixtures”, Molecules 2020, 25, 2038 (Zuorro), cellulose is organized in microfibrils containing both crystalline and amorphous regions. Microfibrils are assembled into fibers of larger diameter that are cross-linked by hemicelluloses and embedded in a gel-like pectic matrix. The degree of cellulose crystallinity and the spatial organization of the cellulose/hemicellulose network are mainly determined by intra- and intermolecular hydrogen bonds, formed between hydroxyl groups present in the β-1,4-linked D-glucopyranose units of cellulose. Solvent molecules of small size and high polarity can penetrate the plant matrix and adsorb on these hydroxyl groups. Following adsorption, some bonds are broken, increasing the distance between the cellulose fibers, and causing the material to swell. In most cases, swelling is limited to the amorphous regions of cellulose, which are more reactive and accessible to solvent. Moreover, a multi-polar blended solvent system is best for extracting lycopene from tomato pomace. Conventionally, a hexane-ethanol-acetone blend provides optimum extraction efficiency. However, tests substituting ethyl lactate, also an excellent solvent for lycopene, for the hexane component of the solvent blend produces inferior extraction efficiency. The cause for this is attributed to solvent complexation between ethyl lactate and ethanol molecules, resulting in reduced plant tissue swelling.
[0168] As such, an important aspect of the present invention is that dense phase CO.sub.2 behaves as a penetrant and plasticizer for polymeric matrices. This beneficial characteristic is related to liquid phase organic solvent expansion effects and is well established in the prior art for many different solid phase organic polymers. For example, in Sawan, S. P. et al., “Evaluation of Interactions Between Supercritical Carbon Dioxide and Polymer Materials”, Los Alamos National Laboratory, Report LA-UR-94-2341, 1994 (Sawan), Sawan states that high pressure carbon dioxide can cause absorption, swelling, and solvation of some polymers as evidenced by weight change data from treatments in dense phase carbon dioxide (liquid and supercritical). Amorphous polymers such as PMMA, PETG, ABS, CAB, and HIPS show more significant absorption, swelling and solvation than crystalline polymers. Moreover, Sawan emphasizes that dense phase carbon dioxide plasticizes most polymers and can cause a significant reduction in glass transition temperature (Tg). Given this, dense phase CO.sub.2 used as a component in aqueous solvent blends assists with solvent penetration and solvation of organic extracts contained within cellulosic plant structures. For example, the ethyl lactate-ethanol complexation constraint described by Zuorro can be mitigated using, for example, an expanding and salting-out solvent blend comprising dense phase CO.sub.2-ethyl lactate-water.
[0169] Biomaterials such as herbs and spices provide a very diverse and complex mixture of hundreds of potentially extractable organic and organometallic chemistries (i.e., phytochemicals) ranging from nonpolar to highly polar compounds; with straight chain to highly branched, to multi-cyclic chemical structures; and exhibiting volatility or non-volatility. All of this is further complicated by physical aspects and properties of the botanical solid substance, for example plant cellulosic structures and plant cellular membrane barriers. As such, many factors must be considered to optimize a biomaterial extraction process. Key process variables (KPVs) include: [0170] Extract cohesion chemistry (i.e., dispersive, polar, and hydrogen bonding energies); [0171] Cohesion chemistry of physical structures (i.e., vacuoles, cell walls, membranes, tissues, and organs); [0172] Moisture content; [0173] Botanical material pretreatments such as drying and grinding; [0174] Cohesion chemistry of extraction solvent or solvent blend; [0175] Extraction solvent-solid volume-mass ratio; [0176] Extraction solvent temperature and pressure; [0177] Extraction process intensification energies such as ultrasonics, microwaves, and centrifugation; [0178] Extraction (solvent-substance contact) time; [0179] Extract concentration (change over time); and [0180] Extract recovery process (i.e., prevent degradation or volatile losses).
[0181] Given this, there is no one universal extraction solvent, or one best extraction technique, to perfectly address each of these KPVs. In this regard, the tunable extraction system of the present invention provides a more robust exhaustive extraction process as compared to a conventional so-called tunable solvent system. For example, in U.S. Pat. Nos. '366 and '112 by the first-named inventor of the present invention, the cohesion properties of dense phase CO.sub.2 are adjusted using pressure and temperature, and using organic solvent pre-treatments and modifiers. These conventional tunable solvent systems are also used with process intensification techniques such as phase shifting and centrifugation. The commercial application of a conventional tunable solvent system is detailed by the first-named inventor in Jackson, D., “CO.sub.2 for Complex Cleaning”, Process Cleaning Magazine, July/August 2009 (Jackson).
[0182] In contrast with tunable solvent systems, the present invention uniquely combines the tunable solvent properties of a non-aqueous dense phase CO.sub.2 extraction system and a semi-aqueous solvent extraction system, working cooperatively as a tunable extraction system, to optimize the extraction of organic, inorganic, and ionic compounds from one or a combination of solid and/or liquid substances. The present invention enables in-situ formation and use of blends of dense phase CO.sub.2, semi-aqueous solvent, and expanded/salted-out WSWE compounds in multiphasic liquid-liquid and solid-liquid extractions. These tuned extraction systems are based on like-dissolves-like (i.e., matching dispersive, polar, and hydrogen bonding energies between extraction solvent environment and substance) and like-seeks-like (i.e., maximizing cellular or cellulosic swelling and penetration) principles of Hansen Solubility Parameters. Tunable monophasic, biphasic, and multiphasic solvent chemistry used in combination with extraction process intensification techniques such as optimized thermal and mechanical energy inputs provide an efficient and full-spectrum extraction and recovery process.
[0183] In this regard, it is known in the prior art that utilizing both hydrocarbon-like and water-like cohesion chemistry together in a solvent blend broadens the spectrum of compounds that can be extracted from a botanical compound. For example, hydroethanolic solvents significantly improve the solubility of polar flavonoids, which are bioactive polyphenolic compounds. In Zhang, J. et al., “Solubility of Naringin in Ethanol and Water Mixtures from 283.15 to 318.15 K”, Journal of Molecular Liquids, Volume 203, March 2015, pp. 98-103 (Zhang et al.), it was determined that the hydroethanolic solvent system comprising between 40% and 60% ethanol by volume produced the highest solubility of naringin (from grapefruit peels) between the temperature range of 10° C. to 45° C., with naringin solubility increasing with temperature. In Liu, Y. et al., “Optimization of Extraction Process for Total Polyphenols from Adlay”, European Journal of Food Science and Technology, Vol. 3, No. 4, pp. 52-58, September 2015 (Liu et al.), it was determined that optimal extraction of total polyphenols from botanical solid Adlay (Chinese Barley) occurred with a hydroethanolic solution having 60% (by vol.) ethanol at 40° C. for 1.5 hours. Further to this, the results showed that the impact order of the influence factors was 1. ethanol concentration.fwdarw.2. extraction time.fwdarw.3. extraction temperature. Finally, in de Sousa, C. et al., “Greener Ultrasound-assisted Extraction of Bioactive Phenolic Compounds in Croton heliotropiifolius Kunth leaves”, Microchemical Journal, 159 (2020) 105525 (de Sousa et al.), it was determined that optimal extraction of polyphenolic compounds ranged from 88% to 94% using a hydroethanolic solvent comprising 37.5% (by vol.) ethanol at a temperature of 54.8° C. for 39.5 min in an ultrasonic bath.
[0184] Having discussed the relevant literature research supporting the need for a tunable extraction system, following is a discussion of an exemplary tunable extraction system comprising dense phase (gas-liquid) CO.sub.2, ethanol, and water, and by reference to
[0185]
[0186] Now referring to
[0187] Now referring to
[0188] With respect to both plant structures and phytochemicals, increasing molecular complexity, polar surface area, and molecular weight requires increasing levels of extraction process intensification, for example increasing temperature, solvent agitation, solvent exchange, and solvent cohesion energy, to efficiently drive the botanical extraction process. Solid phase plant structures may be waxy, cutaneous, cellulosic, and generally polymeric in nature. This requires a more complex extraction environment operating at higher temperatures to induce swelling or plasticization to improve solvent access and solubilization of liquid or solid phytochemicals contained therein. This aspect is a primary motivation for the present invention.
[0189] In this regard, and now referring to both
[0190] Finally, the composition of the exemplary CO.sub.2-EtOH-H.sub.2O extraction system (226) is firstly controlled by a volumetric mixture of EtOH (230) and H.sub.2O (232) to form a semi-aqueous mixture preferably ranging between 5%:90% EtOH:H.sub.2O v:v and 30%:70% EtOH:H.sub.2O v:v, and preferably at a temperature between −20° C. and 50° C., which incorporates a heated pressurized semi-aqueous extraction process followed by a much cooler CO.sub.2 SALLE extract concentration and recovery process. As such, the preferred EtOH:H.sub.2O mixture range has a δ.sub.T between approximately 48 and 40 MPa.sup.1/2 at room temperature. The composition of the CO.sub.2-EtOH-H.sub.2O extraction system (226) is secondly controlled by the CO.sub.2 pressure, preferably between 5 atm and 100 atm, to provide a volume of CO.sub.2 gas or liquid (228) as a non-aqueous upper phase. Further to this, CO.sub.2 (228) saturates the EtOH:H.sub.2O semi-aqueous phase with aqueous CO.sub.2, which expands and salts-out a portion of the dissolved EtOH (230) component to form a CO.sub.2-expanded EtOH middle phase located between a lower semi-aqueous phase (principally H.sub.2O) and upper non-aqueous phase (principally CO.sub.2). The CO.sub.2-expanded EtOH middle phase has a δ.sub.T between approximately 20 and 26 MPa.sup.1/2. The CO.sub.2 (1) phase (228) selectively dissolves a portion of the EtOH (230) to form a CO.sub.2 salted-out EtOH mixture, controlled by CO.sub.2 pressure and semi-aqueous solution temperature, and provides a δ.sub.T between approximately 17 and 20 MPa.sup.1/2. Given this, the exemplary CO.sub.2-EtOH-H.sub.2O system (226) provides a δ.sub.T ranging between approximately 17 MPa.sup.1/2 and 48 MPa.sup.1/2, including a range of polarities and hydrogen bonding energies, to provide an optimal solvent environment for the many types of plant structures (200) and phytochemicals (212) found in a botanical system. Finally, process intensification techniques such as heating and ultrasonic homogenization may be used in the EtOH:H.sub.2O semi-aqueous phase. Moreover, process intensification techniques such as a blade mixing or centrifugation may be used in the CO.sub.2-EtOH-H.sub.2O extraction system (226).
[0191] Having discussed the principal rationale for development of the present invention, following is a discussion, by reference to
[0192] Now referring to
[0206] Wherein, said one or more (preferably naturally derived) WSWE compounds are present in a semi-aqueous solution or a CO.sub.2 salted-out solvent mixture at a concentration between 0.1% and 95% by volume. Further to this and in accordance with Hansen Solubility Parameters (Hansen 2007), the exemplary WSWE salting-out compounds, or blends of same, are chosen (or formulated) based on matching the dispersive (δ.sub.D), polar (δ.sub.P), and hydrogen-bonding parameters (δ.sub.H) between the salting-out solvent(s) and the analyte(s) to be extracted from either the solid substance or liquid substance (performing as the aqueous solution), or both. This may also include computations for Solvent Interaction Radius (Ro) and Relative Energy Difference (RED). Still moreover, dense phase CO.sub.2 (i.e., high pressure gas, saturated liquid phase, or supercritical state) serves as the relatively nonpolar salting-out agent and/or co-extractant in each liquid-liquid aqueous solvent scheme developed.
[0207] The volume of WSWE compound (i.e., organic solvent), and number of CO.sub.2 SALLE cycles, needed for a particular application is determined using trial or bench tests which comprise HSP calculations, gravimetric measurements, or instrumental methods of analysis such as Gas Chromatography (GC), Raman Spectroscopy, and High-Performance Liquid Chromatography (HPLC). More preferably, CO.sub.2 SALLE process development is performed in-situ and in real-time using light-induced fluorescence (LIF) spectroscopy.
[0208] An exemplary WSWE compound for use in the present invention is an emulsion. An emulsion is a dispersion of droplets of one liquid in a second immiscible liquid. The droplets are termed the dispersed phase, while the second liquid is the continuous phase. To stabilize an emulsion, a surfactant (i.e., lecithin) and cosurfactant (i.e., ethanol) are added such that the droplets remain dispersed and do not separate out as two phases. Depending on the phase, there are two types of microemulsions: water-in-oil (w/o) and oil-in-water (o/w). Water is the dispersed phase in w/o emulsions, whereas oil is the dispersed phase in o/w emulsions. One of the main differences between emulsions and microemulsions is that the size of the droplets of the dispersed phase of microemulsions is between 5 and 100 nm, while that of emulsions is >100 nm. Microemulsions are thermodynamically stable systems, whereas emulsions are kinetically stable systems. Still moreover, microemulsions are clear, thermodynamically stable isotropic liquid mixtures of hydrocarbons, water, and surfactant, frequently in combination with a cosurfactant, such as an alcohol. The aqueous phase may contain salt(s) and/or other ingredients. In contrast to ordinary emulsions, microemulsions form upon simple mixing of the components and do not require the high shear conditions generally used in the formation of ordinary emulsions.
[0209] Various surfactants, cosurfactants, and emulsifiers may be used to formulate emulsions and microemulsions. In this regard, natural nonionic or ionic plant-based surfactants, for example cetearyl ethoxylate and lecithin, are preferred for use in the present invention so that CO.sub.2 salted-out organic mixtures containing these compounds may be formulated directly into tinctures or foods without toxicity concerns. For example, soy lecithin-ethanol-water mixtures may be used as green, low surface tension hydroethanolic emulsion extractants. During application of these surfactant-based semi-aqueous solutions in plant oil extraction applications, emulsions or microemulsions may form during processing.
[0210] Moreover, a unique method for forming oxygenated emulsifying agents (and emulsions employing same) in-situ is disclosed herein under
[0211] For example, lycopene extract from tomato pomace is intended for use in the following food categories: baked goods, breakfast cereals, dairy products including frozen dairy desserts, dairy product analogues, spreads, bottled water, carbonated beverages, fruit and vegetable juices, soybean beverages, candy, soups, salad dressings, and other foods and beverages. Lycopene is a nonpolar compound that is insoluble in water, but can be selectively dissolved in various hydrocarbon solvents, oils, and blends of same.
[0212] A microemulsion used to extract lycopene from tomato pomace is described in Amiri-Rigi, A et al., “Extraction of Lycopene using a Lecithin-based Olive Oil Microemulsion, Food Chemistry 272 (2019) 568-573 (Amiri-Rigi et al). The microemulsion described in Amiri-Rigi et al. is composed of soy lecithin:1-propanol:olive oil:water (53.33:26.67:10:10 by wt. %). Tomato pomace (both skins and seeds) was chopped up using a blender and was added to centrifuge tubes containing the olive oil microemulsion, following which the centrifuge tubes were placed in a 35° C. shaking water bath for ° minutes to complete the extraction process. Subsequently, mixtures were centrifuged at 18,000 G-force for 15 minutes at room temperature and upper phase was decanted and its lycopene content was measured. The analysis revealed an 88% extraction efficiency. This biocompatible and food-grade microemulsion, following lycopene extraction, can be directly used in food formulations where it provides good solubility in aqueous and nonpolar media and improves the health-promoting properties of both lycopene and olive oil.
[0213] The work described under Amiri-Rigi et al. utilizes a concentrated microemulsion solution to obtain a concentrated mixture of microemulsion and relatively small amount of lycopene extract. This concentrated semi-aqueous extraction solution was employed at a ratio of 1 part tomato pomace to 5 parts extractant. Scaling this extraction process to higher production would require a tremendous amount of concentrated extractant, and a mechanical separation process such as a filter press or centrifuge to separate the biomass from the extractant. Moreover, the large amount of microemulsion extractant used to recover a very low concentration of lycopene extract from the tomato pomace (300 micrograms lycopene/g tomato pomace) may not be necessary.
[0214] As such, the present invention can replace the concentrated microemulsion extractant and high-G force centrifuge separation method of Amiri-Rigi et al. Dilute emulsion and microemulsion chemistries, as concentrated salted-out extractants, may be utilized to extract a large mass of wet tomato pomace. Process intensification techniques such as mixing, heating, centrifugation, and sonication may also be employed.
[0215] For example, a novel water-oxygenated olive oil-olive oil emulsion blend used in combination with dense phase CO.sub.2 and process intensification techniques such as heating and ultrasonics can be used to extract lycopene from tomato peels. Moreover, a unique type of emulsifying agent of the present invention are ozonated (oxygenated) unsaturated organic compounds such as vegetable oils, terpenes, cannabinoids, flavonoids, and carotenoids.
[0216] In another example, lycopene is freely soluble in ethyl acetate (EA), a non-toxic water-soluble (86 g/L at 20° C.) and water-emulsifiable organic compound. As such, aqueous extraction solutions comprising water:EA:lecithin:olive oil or water:EA:lecithin:ethanol, for example, can be formulated and used as primary extractants for lycopene from tomato pomace using the present invention. Following each extraction cycle, the mixture is CO.sub.2 expanded/salted-out to recover the dehydrated lycopene-lecithin-EA-oil mixture using a (HSP optimized) semi-aqueous-dense phase CO.sub.2 extraction method of the present invention. Following this, the phase-separated water may be reformulated to form a dilute emulsion or microemulsion and reused. Moreover, aqueous solutions comprising water, surfactant, and ethyl lactate may be formulated for lycopene extraction as well.
[0217] Again, referring to
[0224] Finally, exemplary liquid substances (256) used for practicing the present invention may contain a significant amount of water with only minimal amounts of natural WSWE compounds, termed dilute liquid substances or solutions. Dilute liquid substances may be re-formulated as more concentrated semi-aqueous solutions by introducing additional WSWE compounds (254). Still moreover, exemplary liquid substances (256) may be mixed with optional WSWE additives such as, for example, water, organic acids and salts, inorganic salts (i.e., Sea Salt, NaCl, K.sub.2CO.sub.3, Na.sub.2SO.sub.4, K.sub.3PO.sub.4, etc.), natural or non-toxic surfactants and cosurfactants, enzymes, pH buffers, chelation agents, and ozone, among other additives which enhance extraction, recovery, or analytical processes herein.
[0225] Further to this, exemplary liquid substances may contain naturally fermented water-soluble organic solvents, and organic solvent-soluble compounds, for example fermented ethanol (EtOH) and EtOH-soluble fermented organic compounds, or may be mixed with semi-aqueous solutions (250) containing WSWE compounds and additives (254) such as alcohols, ketones, esters, vegetable oils, nitriles, inorganic salts, and organic acids and salts, among many other examples, and prior to liquid-liquid or solid-liquid extraction processes and CO.sub.2 SALLE processes described herein.
[0226] For example, with regards to alcoholic beverages, low alcohol content beverages such as beers and wines may be blended with high alcoholic content beverages such as a higher-proof grain alcohol to boost natural fermented ethanol content levels of the mixture while retaining natural flavonoids present in the beers and wines. Blending is useful for producing a minimum volume of infused ethanol extract for effective dense phase CO.sub.2 solid-liquid co-extraction and for formulating natural tinctures, vapes, or for use as food and beverage additives.
[0227] Most legal sources and supplies of grain-based or bio-based ethanol, also termed bio-EtOH herein, for botanical material extraction is also called “denatured ethanol”. Denatured ethanol typically contains up to 10% denaturant compounds (by vol.) that make it poisonous, bad-tasting, foul-smelling, nauseating, or otherwise non-drinkable. Exemplary denaturants include methanol, isopropyl alcohol, acetone, methyl ethyl ketone, and heptane. Adding these denaturants discourages recreational consumption.
[0228] The reasons for this are straightforward. Sales of alcoholic beverages are heavily taxed for both revenue and public health policy purposes. To avoid paying beverage taxes on alcohol that is not meant to be consumed, the alcohol must be denatured, or treated with added chemicals to make it unpalatable. Denatured alcohol is used identically to ethanol itself except for applications that involve fuel, surgical and laboratory stock. Pure ethanol is required for food and beverage applications and certain chemical reactions where the denaturant would interfere. As denatured ethanol is sold without the often-heavy taxes on alcohol suitable for consumption, it can be a much lower cost and purely organic solution for most uses that do not involve drinking, for example botanical material extraction.
[0229] Although denaturing ethanol does not chemically alter the ethanol molecule and its performance in a botanical extraction process, it is intentionally difficult to separate the denaturing component using conventional separation methods such as distillation or membrane filtration processes. However, the downside is that these same denaturants (i.e., poisons) end up as trace components within botanical extraction products such as tinctures and oils. As already discussed herein, it is becoming more desirable to produce completely natural and non-toxic botanical extracts and compounds using organically grown botanical materials absent of pesticides and heavy metals, as well as pure unadulterated extraction solvents.
[0230] Given this, a 100% organic solution to this constraint is to utilize already taxed and unadulterated commercial alcoholic beverages. One exemplary source is a commercial product called Everclear Grain Alcohol, 190 Proof, available from select alcoholic beverage supply stores (and U.S. States). The 190-proof variation of Everclear is 92.4% ethanol by weight, which is produced at approximately the practical limit of distillation purity (95% EtOH:5% Water). However, many U.S. States impose limits on maximum alcohol content or have other restrictions that prohibit the sale of the 190-proof variation of Everclear, and several of those States also effectively prohibit lower-proof Everclear grain alcohol.
[0231] Still moreover, the problem with low-proof grain alcohol is that it is ineffective as a solvent for most botanical material extraction applications, particularly for botanical materials containing target extractable compounds which do not exhibit appreciable water solubility under S.T.P. conditions.
[0232] The present invention provides novel methods and processes for effectively utilizing commercial alcoholic beverages as liquid substances (256) in liquid-liquid and solid-liquid extraction processes of the present invention. Suitable alcoholic beverages range from dilute aqueous alcohol solutions (i.e., Beers, Wines, Ports, etc.) to concentrated aqueous alcoholic solutions (i.e., Whiskeys, Vodkas, Grain Alcohols, etc.), and include blends of same and with various custom additives.
[0233] Commercially available alcoholic beverages are excellent sources of naturally fermented ethanol and a wide variety of naturally fermented EtOH-soluble and dense phase CO.sub.2-soluble organic compounds. During a solid-liquid extraction process, naturally fermented WSWE compounds may be co-extracted and incorporated into a biomaterial extract to impart healthful characteristics or pleasant flavors, colors, and aromas, to form an infused biomaterial extract or tincture.
TABLE-US-00004 TABLE 4 Exemplary Alcoholic Beverages and Chemistries Maximum Alcoholic EtOH Content EtOH-Soluble Compounds Beverage (% by Vol.).sup./1 (Exemplary Fermentation-Distillation By-Products and Additives) Beer 14% Alpha Acids, Beta Acids, Essential Oils, Esters Vodka 95% Ethanol Hydrates, Citric Acid, Organic Alcohols, Glycerol, Coumarin Port 20% Anthocyanins, Sotolon, Whisky Lactones Rum 75% Esters, Vanillin, Gualacol, Organic Acids, Organic Alcohols, Gin 68% Juniper Berry Compounds, Limonene, Myrcene, Linalool, Geranyl Acetate Whiskey 65% Whiskey Lactones, Aldehydes, Esters, Phenolics, Organic Alcohols Tequila 40% Isovaleraldehyde, Isoamyl Alcohol, B-Damascenone, Vanillin Red Wine 12% Anthocyanins, Tannins, Flavan-3-ols, Flavonols Baijiu 65% Organic acids, Esters, Lactones, Phenols, Heterocycles, Terpenes, Aromatics
1. Very High EtOH Content Alcoholic Beverages May not be Commercially Available.
[0234] Exemplary alcoholic beverages and chemistries are shown in Table 4. There are many types and sources of both fermented and distilled alcoholic beverages, and innumerable blends and additives, suitable as liquid substances (256) for practicing liquid-liquid and solid-liquid extraction and extract recovery methods and processes of the present invention.
[0235] Some of which are exotic, ancient, and contain very healthful (ethanol and CO.sub.2 solvent-soluble) ingredients, such as Baijiu, an ancient Chinese liquor and is the national liquor of China. The production of baijiu is different from that of other exemplary distilled liquors listed in Table 4 because it combines the two distinctive processes of fermentation and distillation. It may also be unique from a human health perspective as well. According to Liu, H. and Sun, B., “Effect of Fermentation Processing on the Flavor of Baijiu”, J. Agric. Food Chem., 2018, 66, pp. 5425-5432 (Liu and Sun), Liu and Sun state that Baijiu is rich in many flavor components, including organic acids (such as acetic, citric, lactic, malic, tartaric, and linoleic acids) and salts, esters (such as ethyl acetate, ethyl lactate, and ethyl hexanoate), lactones, phenols, heterocycles, terpenes, and aromatic compounds. Furthermore, Baijiu contains potential functional components, such as amino acids and peptides which are beneficial to humans. The first economic history book from China, “Shi-Huo-Zhi” by Ban Gu, reported that Baijiu has long been used as a base for traditional Chinese medicine, at least since the Eastern Han dynasty.
[0236] Exemplary liquid substances (256) may be mixed with semi-aqueous solutions containing water-soluble additives such as, for example, organic acids and salts, inorganic salts (i.e., Sea Salt, NaCl, K.sub.2CO.sub.3, Na.sub.2SO.sub.4, K.sub.3PO.sub.4, etc.), natural or non-toxic surfactants and cosurfactants, enzymes, pH buffers, chelation agents, and ozone, among other additives.
[0237] In
[0238] Exemplary solid substances (258), and mixtures of same, include: [0239] 1. Natural products such as nuts, spices, herbs, hops, roots, dried fruits, bark, hemp, and psychoactive plants such as Cannabis sativa, cannabis indica, and Cannabis ruderalis. [0240] 2. Pomaces (food wastes skins, stems, seeds) such as tomato pomace, carrot pomace, apple pomace, and grape pomace. [0241] 3. Animal tissues such as skin, hair, bones, muscles, and organs. [0242] 4. Soils such as ocean outfall sediments, USEPA superfund site soils. [0243] 5. Semi-solids such as sludge and slurry.
[0244] Further to this, and discussed under
[0245] Still referring to
[0250] Moreover, said one or more solid substances (258) may be co-extracted together in said semi-aqueous solution, or in a dense phase CO.sub.2 or CO.sub.2 salted-out solvent mixture during a subsequent CO.sub.2 SALLE process. Alternatively, said one or more solid substances (258) may be co-extracted separately in said semi-aqueous solution, or in a dense phase CO.sub.2 or CO.sub.2 salted-out solvent mixture, for example as described in a cluster extraction process under
[0251] An exemplary extraction process used in a tunable extraction system in combination with a CO.sub.2 SALLE process is a modified subcritical water extraction (MSWE). Again, referring to
[0252] Still referring to
[0253] Having discussed exemplary aspects of a tunable extraction system used in combination with a CO.sub.2 SALLE process, following is a description of three exemplary CO.sub.2 SALLE methods derived from
CO.sub.2 SALLE Method I: CO.sub.2-L-A/B (320)
[0254] In this exemplary CO.sub.2 SALLE method, a semi-aqueous solution (326) containing one or more WSWE compounds and optional additives (naturally present or purposely added) and containing one or more dissolved target extracts, is expanded/salted-out and co-extracted using dense phase CO.sub.2 (328) to recover said extracts from said semi-aqueous solution (326), the method comprising: [0255] 1. A semi-aqueous solution (326) comprising 100 Proof Vodka (approximately 50% by volume fermented ethanol (i.e., a natural WSWE compound) and 50% by volume water), is placed in a pressure vessel (327); [0256] 2. Dense phase CO.sub.2 (328) is injected and bubbled (as a near-cryogenic CO.sub.2 gas-solid aerosol) through said semi-aqueous solution (326) to cool and saturate with CO.sub.2 to a pre-determined temperature between about 20° C. and −40° C. at a sublimating vapor pressure of about 3 atm (i.e., continuously venting to atmosphere), following which said cooled and CO.sub.2-saturated semi-aqueous solution is autogenously pressurized (vis-à-vis sublimation pressurization and temperature rise) or mechanically pressurized with dense phase CO.sub.2 (328) using a pump (preferred) to a pressure between 5 atm and 90 atm to selectively (and volumetrically) expand/salt-out to form a fermented ethanol-rich CO.sub.2 salted-out solvent mixture (330) above said semi-aqueous solution and a liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (332) above said ethanol-rich phase (330). The multiphasic mixture thus formed is preferably turbulently mixed and allowed to stratify into distinct phases as shown; [0257] 3. A portion of said fermented ethanol-rich CO.sub.2 salted-out solvent mixture (330) is subsequently dissolved into said liquid CO.sub.2-rich phase (332); and [0258] 4. Said CO.sub.2 salted-out solvent mixtures are desolvated to recover fermented ethanol and CO.sub.2.
[0259] Exemplary Desolvation and Extract Recovery Methods A and B comprise the following:
[0260] Desolvation-Extract Recovery Method A (334): CO.sub.2 salted-out solvent mixture phase (330), which is rich in fermented EtOH, is decanted under CO.sub.2 gas pressure for extract concentration and recovery, for example, using isostatic pressure distillation. Alternatively, the CO.sub.2 salted-out solvent mixture (330) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
[0261] Desolvation-Extract Recovery Method B (336): CO.sub.2 salted-out solvent mixture phase (332), which is rich in liquid CO.sub.2, is decanted under CO.sub.2 gas pressure for extract concentration and recovery, for example, using a near-cryogenic CO.sub.2 gas-solid aerosol spray separation process. Alternatively, the CO.sub.2 salted-out solvent mixture (332) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
CO.sub.2 SALLE Method II: CO.sub.2-L-S.sub.L-A/B/C (322)
[0262] In this exemplary CO.sub.2 SALLE method, a semi-aqueous solution (338) containing a WSWE compound (naturally present or purposely added) is co-extracted with a liquid-immersed solid substance (S.sub.L) (340) containing one or more soluble extracts, and which is contained in a porous container or centrifuge basket (342). The semi-aqueous solution (338) and solid substance (S.sub.L) (340) mixture are expanded/salted-out and co-extracted with dense phase CO.sub.2 (344) to extract and recover soluble extracts, the method comprising: [0263] 1. A solid substance (S.sub.L) (340) containing one or more dissolved target extracts, and enclosed within a porous container or centrifuge basket (342), is positioned within a pressure vessel (344); [0264] 2. Said pressure vessel (344) containing said solid substance (S.sub.L) (342) is filled with a semi-aqueous solution (338) containing an extraction mixture comprising 60% by vol. water, 40% by vol. ethyl acetate, and in contact with immersed solid substance (S.sub.L) (342); [0265] 3. Dense phase CO.sub.2 (344) is injected and bubbled (as a near-cryogenic gas-solid aerosol) through said semi-aqueous solution to cool and saturate the semi-aqueous solution (338) and solid substance (S.sub.L) (340) with CO.sub.2 to a pre-determined temperature between about 20° C. and −40° C. at a sublimating vapor pressure of about 3 atm (i.e., pressure maintained by continuously venting sublimated CO.sub.2 gas to atmosphere), following which said cooled and CO.sub.2-saturated semi-aqueous solution (338) and immersed solid substance (S.sub.L) (342) is autogenously pressurized (vis-à-vis sublimation pressurization and temperature rise with the pressure vessel (344) vent closed) or mechanically pressurized with dense phase CO.sub.2 using a pump (preferred) to a pressure between 5 atm and 90 atm to selectively (and volumetrically) salt-out and form an ethyl acetate-rich CO.sub.2 salted-out solvent mixture (346) above said semi-aqueous solution (338) and a liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (348) above said ethyl acetate-rich phase (346). The multiphasic mixture thus formed is preferably turbulently mixed and allowed to stratify into distinct phases as shown; [0266] 4. A portion of said salted-out ethyl acetate-rich CO.sub.2 salted-out solvent mixture (346), containing one or more dissolved extracts removed from the solid substance (S.sub.L) (340), is subsequently dissolved into said CO.sub.2-rich CO.sub.2 salted-out solvent mixture (348); and [0267] 5. Said CO.sub.2 salted-out solvent mixtures (346, 348) are desolvated to recover dissolved extracts, ethyl acetate, and CO.sub.2. Moreover, said semi-aqueous solution (338) is decanted for additional processing and recycled back into the exemplary CO.sub.2 SALLE method.
[0268] Exemplary Desolvation and Extract Recovery Methods A, B, and C comprise the following:
[0269] Desolvation-Extract Recovery Method A (350): CO.sub.2 salted-out solvent mixture phase (346), which is rich in ethyl acetate, is decanted under CO.sub.2 gas pressure for extract concentration and recovery, for example, using isostatic pressure distillation. Alternatively, the CO.sub.2 salted-out solvent mixture (346) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
[0270] Desolvation-Extract Recovery Method B (352): CO.sub.2 salted-out solvent mixture phase (348), which is rich in liquid CO.sub.2, is decanted under CO.sub.2 gas pressure for extract concentration and recovery using, for example, distillation or near-cryogenic CO.sub.2 solid-gas aerosol spray desolvation. Alternatively, the CO.sub.2 salted-out solvent mixture (348) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
[0271] Desolvation-Extract Recovery Method C (354): CO.sub.2 salted-out solvent mixtures (346, 348) (including solubilized and suspended compounds) and semi-aqueous solution (338) are decanted under CO.sub.2 gas pressure for further processing such as centrifugation, Dissolved CO.sub.2 Flotation (DCF), and oil skimming to recover extracted and precipitated extracts from the surface of the CO.sub.2 salted-out aqueous solution. Once processed to remove extracted compounds, said processed CO.sub.2 salted-out semi-aqueous solution may be recycled back into the original extraction process for reuse.
CO.sub.2 SALLE Method III: CO.sub.2-L-S.sub.CO2-A/B (324):
[0272] In this exemplary CO.sub.2 SALLE method, a solid substance (S.sub.CO.sub.
[0273] 1. A pressure vessel (364) is partially filled with a semi-aqueous solution (360), which comprises water and a water-soluble water-emulsifiable compound (and optionally other additives);
[0274] 2. A solid substance (S.sub.CO2) (356) containing one or more extracts, and contained within a porous container or centrifuge basket (358), is positioned above said semi-aqueous solution (360) within said pressure vessel (364);
[0275] 3. Dense phase CO.sub.2 (362) is injected and bubbled (as a near-cryogenic CO.sub.2 gas-solid aerosol) through said semi-aqueous solution (360) to cool and saturate the extraction system comprising semi-aqueous solution (360) and solid substance (S.sub.CO2) (356) with CO.sub.2 to a pre-determined temperature between about 20° C. and −40° C. at a sublimating vapor pressure of about 3 atm (i.e., pressure maintained by continuously venting to atmosphere), following which said cooled and CO.sub.2-saturated semi-aqueous solution (360) and solid substance (S.sub.CO2) (356) is autogenously pressurized (vis-à-vis sublimation pressurization and temperature rise with the pressure vessel (364) vent valve closed) or mechanically pressurized with dense phase CO.sub.2 (362) using a pump (preferred) to a pressure between 5 atm and 90 atm to selectively (and volumetrically) salt-out and form a WSWE-rich CO.sub.2 salted-out solvent mixture (366) as a phase containing said extracts above said semi-aqueous solution (360) and a liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (368) above said WSWE-rich phase. The multiphasic mixture thus formed is preferably turbulently mixed and allowed to stratify into distinct phases as shown;
[0276] 4. A portion of said WSWE-rich CO.sub.2 salted-out solvent mixture (366) containing one or more dissolved extracts removed from said solid substance (S.sub.CO2) (356) is subsequently dissolved into said liquid CO.sub.2-rich CO.sub.2 salted-out WSWE mixture (368); and
[0277] 5. Said WSWE-rich and Liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixtures (366, 368) are desolvated to recover solvated and desolvated extracts, WSWE, and CO.sub.2.
[0278] Exemplary Desolvation and Extract Recovery Methods A and B comprise the following:
[0279] Desolvation-Extract Recovery Method A (370): WSWE-rich CO.sub.2 salted-out solvent mixture (366) phase is decanted under CO.sub.2 gas pressure for extract concentration and recovery, for example, using isostatic pressure distillation. Alternatively, WSWE-rich CO.sub.2 salted-out solvent mixture (366) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
[0280] Desolvation-Extract Recovery Method B (372): Liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (368) is decanted under CO.sub.2 gas pressure for extract concentration and recovery using, for example, distillation or near-cryogenic CO.sub.2 solid-gas aerosol spray desolvation. Alternatively, Liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (368) is decanted and analyzed using an analytical chemical process, for example, using instrumental techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), UV-VIS spectroscopy, and light-induced fluorescence (LIF) spectroscopy.
[0281] Moreover, exemplary CO.sub.2 SALLE Methods I, II, and III may be operated at subcritical water-supercritical CO.sub.2 solvent system temperatures as high as 300° C. and CO.sub.2 pressures as high as 5,000 psi (340 atm), in a CO.sub.2-solvent modified subcritical water solid-liquid extraction process. However, it is preferred that the semi-aqueous extractant temperature be reduced (cooled) to below 100° C., and most preferably below 30° C., prior to phase stratification and desolvation steps to maximize CO.sub.2 expanded/salted-out WSWE phase volume and to prevent boiling and formation of high temperature water vapor.
[0282] Still moreover, the prior art establishes that efficient subcritical water extractions are possible at temperatures of 150° C. or lower and vapor pressures of 20 atm or lower in many different solid-liquid extraction applications. This is an important aspect because higher processing temperatures waste energy and decompose or denature labile organic extracts. In this regard, and discussed in detail under
[0283] Still moreover, liquid and/or solid substances may be pretreated before or during CO.sub.2 SALLE Method I, II, and III using process intensification techniques such as grinding, ultrasonics (US), microwaves (MW), and centrifugation (CF) to enhance extraction, desolvation, and extract recovery processes of the present invention. Treatment techniques (pre-treatments and in-situ treatments) employing high frequency (i.e., 20/40 kHz) or low frequency (i.e., 300 Hz) acoustics, 2.45 GHz microwaves, and bi-directional centrifugation are used herein to intensify the CO.sub.2 SALLE process to improve extraction efficiency and the recovery of valuable compounds.
[0284]
[0285] An exemplary cluster extraction application is described under
[0286] In this regard, fermented and botanical solid organic compounds dissolved in a dense phase CO.sub.2-ethanol mixture behave as co-extractants. These co-extractants beneficially modify the solubility chemistry of the dense phase CO.sub.2, imparting a broader spectrum of functional group chemistries and associated dispersive, polar, and hydrogen bonding properties. Prior art research establishes that a mixture of secondary natural co-extractants used with a primary extraction solvent and biomaterial improves the dynamics and performance of the extraction process through synergistic changes in the overall solubility chemistry and transport phenomenon associated with the biomaterial solid-liquid solvent extraction system.
[0287] An example of the co-extraction effect is found in Ciurlia, L. et al., “Supercritical Carbon Dioxide Co-Extraction of Tomatoes (Lycopersicum esculentum L.) and Hazelnuts (Corylus avellana L.): A New Procedure in Obtaining a Source of Natural Lycopene”, J. of Supercritical Fluids, 49 (2009) 338-344, (Ciurlia et al.). Ciurlia et al. performed a supercritical CO.sub.2 extraction test comprising dried tomato powder mixed with ground roasted hazelnuts to simultaneously co-extract lycopene from the tomatoes and oils (and other compounds) from the hazelnuts. This extraction procedure was compared to a separate supercritical CO.sub.2 extraction procedure under the same pressure, temperature, and flow conditions using liquid hazelnut oil mixed with tomato powder. Ground hazelnut solid co-extraction resulted in greater than 70% lycopene recovery, while hazelnut oil as a co-solvent in scCO.sub.2 resulted in only 30% recovery. In the co-solvent process, the oil extraction was rapid at the beginning of the process, as the oil was transported and not extracted by the supercritical fluid. On the contrary, the co-extraction process showed that the hazelnut oil was gradually extracted from solid hazelnuts with a trend representing a two-mechanism extraction process. Ciurlia et al. hypothesized that a diffusion-controlled extraction of embedded oil in the ground hazelnuts allows a better solubilization of lycopene (over time) into co-extracted hazelnut oil. This diffusion-controlled mechanism enables more efficient lycopene extraction, with the consequent increase of lycopene yield as compared to CO.sub.2 dopants or co-solvents.
[0288] Another example of the co-extraction effect is found in Aris, et al., “Effect of Particle Size and Co-Extractant on Momordica Charantia Extract Yield and Diffusion Coefficient using Supercritical CO.sub.2”, Malaysian Journal of Fundamental and Applied Sciences, Vol. 14, No. 3, (2018), 368-373 (Aris et al.). Aris et al. determined that co-extracting biomaterial Momordica Charantia pre-soaked in methanol with supercritical CO.sub.2 increased extraction efficiency of the target compound, charantin. In addition, pre-grinding the Momordica Charatia to a particle size of 0.3 mm was found to be optimal for extraction efficiency. Aris et al. concluded that mean particle size of 0.3 mm gave the highest extract yield of 3.32% and 1.34% respectively for with and without the methanol co-extractant, respectively. Moreover, the value of the diffusion coefficient (D.sub.e) at 0.3 mm mean particle size, with and without the methanol co-extractant was determined to be 8.820×10.sup.−12 and 7.920×10.sup.−12 m.sup.2/s, respectively.
[0289] Now referring to
Step 1—CO.sub.2 SALLE Method I: CO.sub.2-L (380);
Step 2—Secondary Infusion: CO.sub.2—S.sub.S-CO2 (382); and
Step 3—Primary Extraction: CO.sub.2—S.sub.P-CO2 (384).
[0290] In this exemplary CO.sub.2 SALLE method, said cluster extraction processing steps are performed sequentially and selectively using three discrete pressure vessels which are fluidly interconnected using high pressure lines, and facilitated with valves, level sensors, temperature and pressure sensors, liquid substance transfer valve, and at least one dense phase CO.sub.2 pump (all not shown). Further to this, said processing steps may be selectively employed to control the amount of co-extractants delivered into each sequential process step. This aspect is facilitated by high pressure lines and by-pass valves (all not shown).
Step 1—CO.sub.2 SALLE Method I: CO.sub.2-L (380)
[0291] In a first step of this exemplary CO.sub.2 SALLE cluster extraction method, an alcoholic beverage (386), an exemplary semi-aqueous solution and liquid substance, containing fermented ethanol and ethanol-soluble organic compounds, is expanded/salted-out and co-extracted using dense phase CO.sub.2 (388) to form a CO.sub.2 salted-out ethanol mixture, the method comprising: [0292] 1.1 An alcoholic beverage (386) comprising 100-Proof Vodka (approximately 50% by volume fermented ethanol (i.e., a natural WSWE compound) and 50% by volume water), is placed in a CO.sub.2 SALLE pressure vessel (390); [0293] 1.2 Dense phase CO.sub.2 (388) is injected and bubbled (as a near-cryogenic CO.sub.2 gas-solid aerosol) through said alcoholic beverage (386) to cool and saturate with CO.sub.2 to a pre-determined temperature between about 20° C. and −40° C. at a sublimating vapor pressure of about 3 atm (i.e., continuously venting to atmosphere), following which said cooled and CO.sub.2-saturated semi-aqueous solution is autogenously pressurized (vis-à-vis sublimation pressurization and temperature rise) or mechanically pressurized with dense phase CO.sub.2 (388) using a pump (preferred) to a pressure between 5 atm and 90 atm to selectively (and volumetrically) expand/salt-out to form a fermented ethanol-rich CO.sub.2 salted-out solvent mixture (392) phase located above said alcoholic beverage (386) and a liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (394) phase located above said ethanol-rich phase (392). The multiphasic mixture thus formed is preferably turbulently mixed and allowed to stratify into two or three distinct phases as shown; and [0294] 1.3 A portion of said fermented ethanol-rich CO.sub.2 salted-out solvent mixture (392) is subsequently dissolved (396) into said liquid CO.sub.2-rich phase (394).
Step 2—Secondary Infusion: CO.sub.2—S.sub.S-CO.sub.
[0295] In a second step of this exemplary CO.sub.2 SALLE cluster extraction method, said one or both CO.sub.2 salted-out solvent mixtures (392, 394) from CO.sub.2 SALLE pressure vessel (390) is transferred (398) under CO.sub.2 pressure into a secondary infusion pressure vessel (400) containing a mixture of solid substances to form an infused CO.sub.2 salted-out solvent mixture, the method comprising: [0296] 2.1 Said one or both CO.sub.2 salted-out solvent mixtures (392, 394) from CO.sub.2 SALLE pressure vessel (390) is transferred (398) under CO.sub.2 pressure into a secondary infusion pressure vessel (400); [0297] 2.2 Said secondary infusion pressure vessel (400) contains one or more secondary solid substances, for example a combination of ground herbs (402) and ground spices (404), which are contained in a porous container (406); and [0298] 2.3 Said one or both CO.sub.2 salted-out solvent mixtures (392, 394) penetrate (408) said herbs (402) and spices (404) and extract (410) organic compounds contained therein to form an herb/spice-infused CO.sub.2 salted-out solvent mixture (412).
Step 3—Primary Extraction: CO.sub.2—S.sub.P-CO.sub.
[0299] In a third and final step of this exemplary CO.sub.2 SALLE cluster extraction method, herb/spice-infused CO.sub.2 salted-out solvent mixture (412) from the secondary infusion pressure vessel (400) is transferred (414) under CO.sub.2 pressure into a primary extraction pressure vessel (416) containing a primary solid substance to form an herb/spice-infused tincture containing a primary extract, the method comprising: [0300] 3.1 Said herb/spice-infused CO.sub.2 salted-out solvent mixture (412) from the secondary infusion pressure vessel (400) is transferred (414) under CO.sub.2 pressure into a primary extraction pressure vessel (416); [0301] 3.2 Said primary extraction pressure vessel (416) contains a primary solid substance, for example ground and dried cannabis (418), and is contained in a porous basket (420); and [0302] 3.3 Said herb/spice-infused CO.sub.2 salted-out solvent mixture (412) penetrates (422) said cannabis (418) and extracts (424) organic compounds contained therein to form an herb/spice-infused tincture (426) containing a primary extract.
[0303] Finally, and still referring to
[0304] Having described exemplary CO.sub.2 SALLE methods, following is a discussion of a novel hybrid subcritical water-CO.sub.2 SALLE process utilizing a modified heated and pressurized water or semi-aqueous extraction process in combination with a CO.sub.2 SALLE process.
[0305] As discussed under
[0306] Besides serving as a medium for adding beneficial thermal and mechanical energy to a solid-liquid extraction system, a particularly useful aspect of subcritical water is its ability to change cohesion energy based on temperature. As the temperature of water is increased, with an increasing autogenous or artificial vapor pressure to prevent boiling, its cohesion energy is decreased. At a temperature of 300° C. and a vapor pressure of 85 atm, subcritical water exhibits a cohesion energy like an alcohol. As such, subcritical water is a green solvent technology that can provide hydrocarbon-like solvent properties, and which is non-toxic and non-flammable. However, to achieve hydrocarbon-like conditions, a high temperature and pressure must be established. This can be deleterious to phytochemicals and poses high-pressure equipment corrosion and worker safety issues. Moreover, and as discussed herein under prior art, concentrating and recovering extracts is energy intensive and slow. As such, an aspect of the exemplary hybrid subcritical water-CO.sub.2 SALLE process is to lower operating temperatures and pressures needed to achieve full-spectrum solvency. Another aspect of the hybrid extraction process is to simplify and lower energy required to concentrate, desolvate, and recover subcritical water extracts.
[0307] A hybrid subcritical water-CO.sub.2 SALLE extraction process uses water-alone or as a WSWE-modified subcritical water solution in a subcritical water extraction process, followed by an exemplary CO.sub.2 SALLE process to concentrate, desolvate, and recover one or more phytochemicals derived from said subcritical water extraction process. For example, a mixture of water and biomaterial is heated and pressurized using N.sub.2 (g) or CO.sub.2 (g). One or more WSWE compounds and optional additives may be added to the water prior to heating and performing a primary extraction process, called a modified subcritical water extraction (MSWE) system or process. If CO.sub.2 (g) is used in a MSWE process, pressure- and temperature-tunable monophasic or biphasic MSWE extractions may be performed. Alternatively, one or more WSWE compounds and optional additives may be added to an unmodified subcritical water extractant following the primary extraction process and during a CO.sub.2 SALLE process.
[0308] Conventional SWE processes employ pressurized N.sub.2 (g) to purge dissolved oxygen gas from water to prevent extract oxidation and to provide a vapor pressure to prevent water from boiling at elevated extraction temperatures. By contrast, dense phase CO.sub.2 is employed in the exemplary hybrid subcritical water-CO.sub.2 SALLE process for a variety of useful purposes: (1) a dissolved air purging and gas flotation agent; (2) a vapor pressure control agent; (3) a water acidification agent; (4) a water-ionized and hydrated agent; (5) a dissolved WSWE compound expansion agent; (6) a co-extraction agent; (7) a near-cryogenic sublimation cooling (and CO.sub.2 saturation) agent; and (8) a sublimating desolvation agent.
[0309]
[0310] For example, Plaza et al.,
[0311] As such, in the SWE process, water must be heated (and pressurized) to above 300° C. (according to the δ.sub.T-° C. curve under Plaza et al.,
[0312] Now referring to
[0313] In this regard, and still referring to
[0314]
[0315] It is well established in the prior art that optimal extraction efficiency is attained using a conventional SWE process at a temperature of 150° C. or less, and an extraction time of 30 minutes or less. For example, Saim, N. et al., “Subcritical Water Extraction of Essential Oils from Coriander (Coriandrum sativum L.) Seeds”, The Malaysian Journal of Analytical Sciences, Vol. 12, No. 1, 2008 (Saim et al.) investigated the use of SWE in the extraction of essential oil from coriander (Coriandrum sativum L.) seeds. Ground coriander seeds were subjected to SWE with water for an extraction time of 15 min under several extraction conditions comprising vapor pressures of 60 atm and 70 atm and temperatures of 65, 100 and 150° C. Saim et al. compared the SWE method extraction efficiency with another water-based extraction technique called hydrodistillation, a process that requires approximately 3 hours to complete. Extracted compounds dissolved in water-based extractants from the SWE method and hydrodistillation method were extracted with hexane and determined by gas chromatography mass spectrometry (GC-MSD). Saim et al. determined that the efficiency (g oil/g of coriander) of SWE was higher than that provided by hydrodistillation with reduced extraction time. The major compounds found were linalool, isoborneol, citronellyl, butyrate, and geraniol. Further to this, Saim et al. determined that the SWE method has the possibility of manipulating the composition of the oil by varying the temperature and adjusting the pressure. Moreover, vapor pressure was found to be an unimportant key process variable (KPV). SWE temperature was determined to be the main driver. This is indicative of the heating effect on decreasing hydrogen bonding energy (C) to produce an extraction chemistry with a lower cohesion energy. Based on
[0316] Finally, the investigation of Saim et al. showed that the thermal effect (
[0317] A solid-liquid phase extraction utilizing said hybrid MSWE-CO.sub.2 SALLE process can be performed sequentially and in-situ using a single pressure vessel system. However, a single pressure vessel system is mainly useful for R&D systems without time and capacity constraints. More preferably, and for high-capacity extraction applications, multiple pressure vessel systems are used in sequence to optimize time, energy, extraction capacity, and extract and extraction media recovery operations. An exemplary multiple vessel processing system is described under
[0318]
[0323] Said pressure vessel subsystems are designed and constructed using materials suitable for operating at the exemplary temperatures and pressures and employing CO.sub.2 and water-based process fluids of the present invention. In this regard, stainless steel or Hastelloy, Haynes® high performance alloys, are preferred materials of construction.
[0324] The semi-aqueous solution pressure vessel subsystem (480) is thermally insulated and equipped with a heating means (488) such as a steam heat exchanger, a thermostatically regulated electric band heater, or a recirculating fluid heater system capable of preheating the subsystem and semi-aqueous solution content to a maximum temperature of about 100° C., and a mixing means (490) such as a magnetically-driven mixing blade or a recirculating fluid heater-in-line static mixing system.
[0325] The MSWE pressure vessel subsystem (482) is thermally insulated and equipped with a heating means (492) such as a thermostatically regulated electric band heater or a recirculating fluid heater system capable of heating the subsystem and contents to an extraction temperature between 50° C. and 150° C., a mixing means comprising a magnetically-driven bladed centrifuge drum (494) with a torque as needed to rotate a centrifuge basket and biomaterial content, while mixing with a semi-aqueous subcritical extractant, and a titanium ultrasonic horn (496) with an energy capacity as needed to sonicate subsystem contents contained in said centrifuge drum (494). Said MSWE pressure vessel subsystem is further equipped with a quick-opening closure (500) which can be conveniently opened and closed (502) to insert and withdrawal (504) a centrifuge basket (506) containing a dried or dewatered biomaterial.
[0326] The CO.sub.2 SALLE pressure vessel subsystem (484) is thermally insulated and equipped with a cooling means (508) such as a chilled-water heat exchanger or a recirculating refrigerated fluid cooling system capable of cooling the subsystem and contents to between −40° C. and 30° C., a mixing means (510) such as a magnetically driven mixing blade or a recirculating refrigerated fluid cooler-in-line static mixing system.
[0327] Finally, the desolvation pressure vessel subsystem (486) is not thermally insulated and is equipped with heating means (512) such as a thermostatically regulated electric band heater circumferentially affixed to the surface of the pressure vessel near the lower hemisphere, and capable of heating the lower section of the subsystem and contents to produce a clean CO.sub.2 (g) distillate temperature between 20° C. and 40° C.
[0328] Having described exemplary features, following is a discussion of high-pressure fluid interconnections and process fluid supply connections between and into the exemplary pressure vessel subsystems. The exemplary pressure vessel subsystems thus described are fluidly interconnected to each other and to external process fluid supplies including water, WSWE compounds and additives, nitrogen gas, and liquid carbon dioxide, referred to as “circuits” herein. Moreover, each subsystem is fluidly connected to either a venting and/or draining circuit, for a total of fifteen fluid transfer circuits (C1-C15).
[0329] Again, referring to
[0330] The MSWE pressure vessel subsystem (482) is fluidly interconnected to the atmosphere through a high-pressure vent line or pipe (524) and atmospheric vent valve (538); collectively referred to as the “MSWE subsystem atmospheric vent circuit (C6)” herein. Moreover, the MSWE pressure vessel subsystem (482) is fluidly interconnected to a source of regulated nitrogen gas through a high-pressure line or pipe (540), nitrogen pressure regulator (542), and nitrogen gas inlet valve (544); collectively referred to as the “nitrogen gas supply circuit (C7)” herein. Finally, the MSWE pressure vessel subsystem (482) is fluidly interconnected to the CO.sub.2 SALLE pressure vessel subsystem (484) using a high pressure semi-aqueous fluid transfer line or pipe (546), fluid filter (547), subcritical water extractant inlet supply valve (548), and cooling heat exchange means (550); collectively referred to as the “subcritical water extractant supply circuit (C8)” herein.
[0331] The CO.sub.2 SALLE pressure vessel subsystem (484) is fluidly interconnected to a source of recycled or make-up CO.sub.2 supply through a high pressure CO.sub.2 inlet line or pipe (552) connected to the upper hemisphere (554) of the desolvation pressure vessel subsystem (486), and through high pressure CO.sub.2 inlet valve (556) and high pressure liquid CO.sub.2 supply (558), CO.sub.2 gas-liquid transfer pump (560), cooling heat exchanger means (562), and liquid CO.sub.2 inlet valve (564); collectively referred to as the “CO.sub.2 supply circuit (C9)” herein. Moreover, the CO.sub.2 SALLE pressure vessel subsystem (484) is fluidly interconnected to a source of WSWE and additives through high pressure supply line or pipe (518), WSWE supply pump (520), and WSWE inlet supply valve (566); collectively referred to as the “CO.sub.2 SALLE WSWE supply circuit (C10)” herein. Still moreover, the CO.sub.2 SALLE pressure vessel subsystem (484) is fluidly interconnected to the WSWE pressure vessel system (482) through high pressure solution recycle line or pipe (568) and solution recycle valve (570); collectively referred to as the “raffinate recycle circuit (C11)” herein. In addition, the CO.sub.2 SALLE pressure vessel subsystem (484) is fluidly interconnected to the drain through high pressure CO.sub.2 SALLE solution drain line or pipe (572) and CO.sub.2 SALLE solution drain valve (574); collectively referred to as the “CO.sub.2 SALLE drain circuit (C12)” herein. Finally, the CO.sub.2 SALLE pressure vessel subsystem (484) is fluidly interconnected to the desolvation pressure vessel system (486) through high pressure CO.sub.2 salted-out solvent mixture line or pipe (576) and CO.sub.2 salted-out solvent mixture valve (578); collectively referred to as the “CO.sub.2 salted-out solvent mixture supply circuit (C13)” herein.
[0332] The desolvation pressure vessel subsystem (486) is fluidly interconnected to high pressure CO.sub.2 inlet line or pipe (552) through the upper hemisphere (554) of the desolvation pressure vessel subsystem (486); collectively referred to as the “CO.sub.2 supply circuit (C9)” herein. Moreover, the desolvation system is fluidly interconnected to the near-cryogenic desolvation system through high pressure CO.sub.2-WSWE-Extract desolvation line or pipe (580), fluid filter (581), and desolvation device (582), discussed in more detail under
[0333] Finally, the exemplary hybrid MSWE-CO.sub.2 SALLE system shown in
[0334] Still referring to
Biomaterial Preparation Process
[0335] A dry biomaterial is ground using a grinder to between about 0.5- and 2-mm particle size using a conventional grinder and poured into a semi-permeable or porous container constructed from a non-contaminating material. Following this, the container of ground biomaterial is placed into a centrifuge basket (506).
Semi-Aqueous Solution Preparation Process
[0336] A predetermined amount of water is introduced into the semi-aqueous solution pressure vessel subsystem (480) through fluid transfer circuit (C1). With the fluid mixing means (490) operational, a predetermined amount of WSWE compound and optional additives is introduced through fluid transfer circuit (C2) and mixed into the water. The mixture is heated using the fluid heating means (488) to a predetermined temperature, for example 80° C., to form a heated semi-aqueous solution (596) therein.
MSWE Pressure Vessel Subsystem Preparation Process
[0337] The closure (500) of the MSWE pressure vessel system (482) is opened (502), following which the centrifuge basket (506) containing pre-ground biomaterial is transferred (504) and placed into the internal centrifuge drum (494). The closure (500) of the MSWE pressure vessel system (482) is closed (502).
Modified Subcritical Water Extraction Process
[0338] The heated semi-aqueous solution (596) contained in the semi-aqueous solution pressure vessel subsystem (480) is pumped into the MSWE pressure vessel subsystem (482) through fluid transfer circuit (C5). Following this, MSWE atmospheric vent valve (538) is opened, and nitrogen gas is introduced through fluid transfer circuit (C7) for a predetermined amount of time at a pressure of 2 atm to remove dissolved oxygen from the heated solution. Following this, nitrogen gas flow is stopped, and with the MSWE atmospheric vent valve (538) still open, the ultrasonic treatment horn (496) is energized for a predetermined amount of time and power level, during which the centrifuge drum is slowly rotated to thoroughly sonicate and degas the biomaterial and solution (598), respectively. Following sonication and degas operations, the MSWE atmospheric vent valve (538) is closed, and nitrogen gas is introduced again through fluid transfer circuit (C7) to provide a suitable internal vapor pressure necessary to prevent solution boiling at operating temperature. For example, the fluid heating means (492) is used to increase the temperature of the semi-aqueous solution (extractant) from 80° C. to 125° C. with a N.sub.2 (g) vapor pressure of 10 atm. During the heating cycle the centrifuge drum is rotated at a predetermined speed, for example between 10 and 100 rpm. Upon reaching the predetermined extraction temperature (and pressure), the heated, pressurized, and dynamic extraction system is maintained for a predetermined amount of time, for example between 15 and 240 minutes. The extraction time is dependent upon the extraction solution temperature, chemical composition of the semi-aqueous solution, and the type and concentration of target phytochemicals. Following completion of the MSWE process, the centrifuge drum is slowed and the primary extractant (600) containing biomaterial extracts is transferred using the N.sub.2 (g) gas pressure, filtered, and cooled in transit through fluid transfer circuit (C8) into the CO.sub.2 SALLE pressure vessel subsystem (484). Following transfer of the primary extractant (600), residual N.sub.2 (g) gas pressure is removed from the MSWE subsystem (482) through MSWE vent circuit (C6). Upon reaching atmospheric pressure, the closure (500) is opened and the centrifuge basket (506) containing the extracted biomaterial is removed from the centrifuge drum and transported (504) to a discard and refill station (not shown).
CO.SUB.2 .SALLE Process
[0339] Pre-cooled primary extractant (600) is further cooled to a predetermined temperature below 30° C. using the cooling means (508), during which mixing means (510) is operating. During cool down and mixing operations, liquid CO.sub.2 is introduced into the CO.sub.2 SALLE subsystem (484) through fluid transfer circuit (C9) to produce a predetermined dense phase CO.sub.2 pressure, for example in discrete stages, between 20 atm and 80 atm, which initiates and progresses the CO.sub.2 expansion and salting-out assisted liquid-liquid extraction process. Liquid CO.sub.2 mixes with the primary extractant (600) to cool and saturate with CO.sub.2, which expands dissolved WSWE compounds and forms aqueous CO.sub.2. Once the desired final CO.sub.2 fluidization pressure is reached, the mixing means (510) is stopped to allow the mixture to separate into distinct phases. The exemplary CO.sub.2 SALLE process produces a biphasic stratification: a lower water-rich primary extractant phase (600), a predominantly aqueous phase, and an upper liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (602), a predominantly non-aqueous phase, containing a dissolved portion of WSWE and extracts phase-separated from the primary extractant (600).
[0340] Following this, a predetermined amount of the liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (602) is withdrawn from the CO.sub.2 SALLE subsystem and transferred to the desolvation subsystem (486) through fluid transfer circuit (C13) for extract concentration, desolvation, and recovery operations. As already discussed herein, the CO.sub.2 SALLE process may be monitored using an analytical chemical process, for example using in-situ instrumental analysis of the non-aqueous or aqueous phases discussed under
Desolvation Process
[0341] Liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture (602) withdrawn from the CO.sub.2 SALLE subsystem, comprising a concentrated mixture of liquid CO.sub.2, WSWE/additives, and solvated or desolvated extracts (604), is heated using heating means (512). Heating the concentrated mixture (604) to between about 25° C. and 40° C. distills out high pressure CO.sub.2 gas (588), which is withdrawn (554), compressed (560), and condensed (562) into a pure liquid CO.sub.2 co-extractant for reuse in the CO.sub.2 SALLE subsystem (484) through fluid transfer circuit (C9). This withdrawal-recycle sequence is repeated as required to completely dissolve and withdraw the CO.sub.2 salted-out solvent mixture from the CO.sub.2 SALLE subsystem (484), which further concentrates the mixture (604) contained in the desolvation subsystem (486). Finally, the CO.sub.2-extracted primary extractant (600) contained in CO.sub.2 SALLE subsystem (484), and now depleted of WSWE compounds and biomaterial extracts, is transferred under CO.sub.2 pressure back to the original semi-aqueous solution pressure vessel subsystem (480) through fluid transfer circuit (C11). The recycled extractant may be reformulated with new or recycled WSWE compounds from the desolvation process. Alternatively, the CO.sub.2-extracted primary extractant (600) is transferred under CO.sub.2 pressure to the drain through fluid transfer circuit (C12).
Extract Recovery and Process Fluids Recycling Process
[0342] The concentrated mixture (604) containing CO.sub.2-WSWE-Extracts is removed under CO.sub.2 gas pressure though fluid transfer circuit (C14). An exemplary desolvation and separation process (590) discussed herein uses a near-cryogenic CO.sub.2 (s.fwdarw.g) aerosol assembly and process described under
Selectivity
[0343] Finally, there are numerous possible solid-liquid and liquid-liquid extraction system and process schemes and configurations utilizing the hybrid subcritical water-CO.sub.2 SALLE process. A novel aspect of the present invention is the ability to be selective (i.e., produce select fractions of a particular polarity of phytochemical extracts) or non-selective (i.e., produce a full spectrum of mixed polarity extracts). An example of a selective process follows. Subcritical water extractant (
[0344] In summary, an exemplary semi-aqueous extraction method using the apparatus and process described under
[0354] The natural product can comprise plant, vegetable, fruit, nut, spice, herb, hops, root, bark, hemp, or cannabis; and said extract is decarboxylated.
[0355] Having described exemplary aspects of a hybrid subcritical water-CO.sub.2 SALLE extraction process under
[0356] In-situ analytical chemical processes are used herein to provide real-time direct or indirect measurement of so-called marker chemicals (key extracts) and WSWE compounds during a CO.sub.2 SALLE process. Analyzing CO.sub.2 salted-out solvent mixtures and/or semi-aqueous extractants provides useful information about the condition and progress of the CO.sub.2 SALLE system and process, respectively. In the following discussion, an exemplary analytical technique called light-induced fluorescence (LIF) spectroscopy is used to measure changes in concentration of a dissolved terpene, d-limonene, contained in the CO.sub.2 salted-out solvent mixture during an exemplary botanical solid-liquid CO.sub.2 SALLE process. Related to this, the relative density of the semi-aqueous extractant is measured to monitor the progress of the WSWE salting-out process. Moreover, although the present example uses a solid botanical material in the exemplary solid-liquid CO.sub.2 SALLE process described under
[0357]
[0358] The LIF optical probe (612) is used to measure the concentration of key “chemical markers” dissolved within the CO.sub.2 salted-out solvent mixture (
[0359] Use of LIF spectroscopy in botanical extractions is well established. For example, LIF spectroscopy is used in CBD fractional distillation processes to determine the quality of a distillate fraction. In Ranzan, C. et al., “Fluorescence Spectroscopy as a Tool for Ethanol Fermentation On-line Monitoring”, 8th IFAC Symposium on Advanced Control of Chemical Processes, Furama Riverfront, Singapore, Jul. 10-13, 2012 (Ranzan et al.), Ranzan et al. details a fluorescence spectroscopy process and system for monitoring and controlling bio-based ethanol production. LIF spectroscopy is used to monitor the progress of the fermentation process based on time-based changes in sucrose, ethanol, biomass, and glycerol concentration within a fermentative broth.
[0360] Another exemplary analytical chemical process is a relative density measurement. An exemplary relative density measurement system uses an open-loop density sensor integrated with a fluid sampling and measurement capillary delivery line, referred to herein as the relative density system (632), as shown in
[0361] The relative density system (632) is used to periodically sample and measure the relative density of the semi-aqueous extractant (
[0362] Finally, and again referring to
[0363]
[0364]
[0365] Having described exemplary aspects of the processes and apparatuses of the present invention, following is a more detailed discussion of the CO.sub.2 aerosol generation system, CO.sub.2 aerosol assembly, and use of same in the present invention.
[0366]
[0367] Now referring to
[0368] For example, an exemplary CO.sub.2 aerosol assembly may be constructed using a 0.25-inch internal diameter (I.D.) stainless steel liquid CO.sub.2 supply valve (704), manual or automatic, connected to a 0.25 inch 18-turn high pressure stainless steel micrometering valve (706), which is manually adjusted and set, and which is connected to a section of 0.040 inch I.D. PEEK J-T expansion tube (710). Said exemplary J-T expansion tube (710) has an I.D. of between about 0.002 inches and 0.040 inches and a length of between about 2 inches and 36 inches. One or more J-T expansion tubes (710) may be connected to one liquid CO.sub.2 micrometering valve (706) to provide a range of cooling capacities ranging from approximately 1000 BTU/hour using a 0.010-inch I.D. J-T expansion tube (710) to 5,000 BTU/hour using a 0.040 inch I.D. J-T expansion tube (710). Said exemplary micrometering valve (706) is adjustable from about 0.002 inch (about 1 turn from fully closed) to 0.040 inch (about 18 turns from fully-closed), and is preferably used with one or more J-T expansion tubes having a combined I.D. of 0.040 inch or less.
[0369] The CO.sub.2 aerosol assembly thus described produces a micronized, relatively low-pressure CO.sub.2 (solid-gas) aerosol (714). Liquid CO.sub.2 (700) is injected through (opened) valve (704), through preset micrometering valve (706), and into said J-T expansion tube (708, 710, or 712). Following injection into said J-T expansion tube (708, 710, or 712), liquid CO.sub.2 instantly begins to boil, super cool, and condense rapidly within the internal volume and along an internal pressure gradient (high.fwdarw.low) within said J-T expansion tube (708, 710, or 712) to form a mixture of microscopic sublimating solid CO.sub.2 particles and expanding cold CO.sub.2 gas having a temperature of −56.6° C. and a pressure of approximately 5.1 atm. Said microscopic sublimating solid CO.sub.2 aerosol particles possess small crystal diameters, ranging from nanometers to micrometers, possess a surface temperature of −78.5 degree C., and produce a rapid and increasing sublimation pressure once injected into solid-liquid or liquid-liquid extraction system. Solid phase CO.sub.2 particles exhibit a hydrocarbon-like HSP of approximately 22 MPa.sup.1/2 with a surface energy (S.E.) of approximately 5 mN/m, which enables rapid surface wetting and solvation into organic WSWE compounds such as ethanol (HSP δ.sub.T—25.8 MPa.sup.1/2, S.E.—21.8 mN/m). Moreover, micronized CO.sub.2 particles have large surface areas and sublimate very quickly following injection. The extraction system remains at approximately ambient pressure during injection and expansion if the system is vented to the atmosphere or increases in pressure during injection if the system vent is closed. This process is called autogenous pressurization or sublimation pressurization.
[0370] Finally, the exemplary CO.sub.2 aerosol assembly of
[0371] Having thus described exemplary and preferred aspects and embodiments of various extraction and desolvation processes and apparatuses of the present invention, following is a discussion of a novel method for producing mixtures of bio-based emulsifiers, including both tinctures and extracts, and emulsions employing same.
[0372]
[0373] Step 1: A method for preparing a bio-based mixture containing one or more oxygenated bio-based emulsifiers, the method comprising:
a. reacting ozonated gas (734), purified air or oxygen, with a decanted and desolvated (i.e., gross CO.sub.2 removed) CO.sub.2 salted-out solvent mixture (730) or tincture containing one or more unsaturated biomaterial and/or alcoholic beverage extracts and additives to form a mixture of unsaturated biomaterial and/or alcoholic beverage extracts and oxygenated extracts and additives, an oxygenated CO.sub.2 salted-out solvent mixture (736); and
b. monitoring and controlling oxygenation level in said oxygenated CO.sub.2 salted-out solvent mixture (736) by light-induced fluorescence spectroscopy, a digital timer, or a viscosity sensor (all not shown);
[0374] wherein said oxygenated CO.sub.2 salted-out solvent mixture (736) may be used directly to form bio-based extract infused water-in-oil and oil-in-water emulsions.
[0375] The method of Step 1, whereby said oxygenated CO.sub.2 salted-out solvent mixture (736) is distilled (738) to form a purified EtOH liquid (740), which may be recycled back to the originating CO.sub.2 SALLE process, and an oxygenated emulsifier concentrate (742). The method of Step 1, wherein the ozonated gas (734) has a concentration between 0.2 mg/hour and 15000 mg/hour of ozone gas at a temperature between −20 degrees C. and 30 degrees C., and a pressure of about 1 atm.
[0376] The method of Step 1, wherein said CO.sub.2 salted-out solvent mixture (730) contains one or more unsaturated natural substances such as cannabinoids, terpenoids, flavonoids, natural oils, bio-based oils and alcohols, garlic oil, lecithin, soybean oil, coconut oil, olive oil, rapeseed oil, corn oil, safflower oil, long-chain alcohol, oleic acid, and oleyl alcohol, among other unsaturated natural and synthetic compounds and mixtures of same, and suitable for use in foods, beverages, pharmaceuticals, cosmetics, and lotions.
[0377] The method of Step 1, wherein said CO.sub.2 salted-out solvent mixture (730) is reacted with the ozonated gas in the presence of deionized water and additives to form an oxygenated emulsion. The method of Step 1, wherein said oxygenated CO.sub.2 salted-out solvent mixture (736) is sparged with compressed air, nitrogen or carbon dioxide for a predetermined period of time to remove residual, unreacted ozone gas.
[0378] The method of Step 1, wherein oxygenated CO.sub.2 salted-out solvent mixture (736) and oxygenated emulsifier concentrate (742) are used as emulsifying agents during the manufacture of foods, beverages, pharmaceuticals, cosmetics, and lotions. The method of Step 1, wherein a source of concentrated oxygen for said ozonated gas (734), and which is used for ozonation reactions, is derived from a semi-permeable gas membrane. The method of Step 1 wherein the level of oxygenated extractable substance formed in said CO.sub.2 salted-out solvent mixture is controlled using a digital timer or viscosity sensor.
[0379]
[0380] Using the hydrophilic-lipophilic balance (HLB) Equation 2 (Eq. 2), described under Griffin, W. C., “Calculation of HLB Values of Non-Ionic Surfactants”, Journal of the Society of Cosmetic Chemists, 5 (4), 1954, pp. 249-256 (Griffin HLB Equation), the HLB value for the oleic acid molecule (750) is increased from HLB=2 (760) to HLB=5 (762). The result of ozonation is an oxygenated oleic acid molecule possessing a 150% increase in HLB value favoring the formation of a water-in-oil emulsion, a 17% increase in molecular mass, increased cohesion energy favoring improved water solubility, a larger polar surface area favoring water solubility, and a higher boiling point.
[0381] Two exemplary bio-based compounds for formulating oxygenated emulsifiers and emulsions using the oxygenation method and process described under
[0382] Finally, the present invention discloses two different methods for producing a decarboxylated extractable substance. Cannabis and hemp, among many other botanical products, in their natural or raw states do not provide potent psychoactive or medicinal effects. Achieving these desirable effects requires a process called decarboxylation. The decarboxylation process “activates” chemical compounds in cannabis and hemp so that the human body can use them. Specifically, raw cannabis and hemp and cannabis contain non-psychoactive and synergistic carboxylic acids such as tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), and cannabigerolic acid (CBGA). When heated, these carboxylic acids transform (over a period of time) to cannabinoids: (psychoactive) tetrahydrocannabinol (THC), (synergistic) cannabidiol (CBD), and (synergistic) cannabigerol (CBG), all with the loss of a CO.sub.2 molecule. These exemplary cannabinoids interact with the body's endocannabinoid system vis-à-vis a psychoactive or non-psychoactive mode.
[0383] A first decarboxylation method comprises a straightforward thermal procedure whereby a desolvated CO.sub.2 salted-out solvent mixture containing extractable substance produced from a plant material is heated to a temperature between 100° C. and 120° C. for a time between 30 minutes and 120 minutes. This method is simple and useful particularly if the WSWE compound containing the extractable substance has a high boiling point, for example a vegetable oil. However, loss of volatile phytochemicals will occur during this process if performed in a system which is open to the atmosphere. A second decarboxylation process is disclosed which performs the decarboxylation process in-situ and within a closed system during a heated water-based extraction process followed by a CO.sub.2 SALLE process, and is discussed in detail under
[0384]
[0385] Compared to conventional decarboxylation processes, the hybrid decarboxylation-extraction process of the present invention provides several operational advantages and distinctions including: 1) eliminating the need for a separate thermal decarboxylation process, 2) elimination of volatile extract losses, 3) elimination of offgassing and outgassing odors common to heated air thermal treatment schemes, and 4) a carbonic acid-catalyzed decarboxylation process. The hybrid decarboxylation-extraction process can be used to process any variety of cannabis and hemp, or any natural product.
[0386] Now referring to
[0387] The exemplary decarboxylation-extraction method comprises the following steps:
[0388] Step 1 (800): Combining fresh or dried, and ground non-psychoactive cannabis (802), contained in a removable porous container (804) such as a glass thimble, perforated basket, porous fabric, or centrifuge drum, and water (806) in a pressure vessel (808). Cannabis (802) varieties include for example Cannabis sativa, cannabis indica, or Cannabis ruderalis. The exemplary cannabis plant contains numerous phytochemicals, including non-psychoactive and synergistic carboxylic acids such as THCA, CBDA, and CBGA. In this example application of the decarboxylation-extraction method, the cannabis plant used contains a significant amount of THCA content to be decarboxylated to the psychoactive THC. The volume (and level) of water (806) and quantity of ground cannabis (802) contained in said pressure vessel (808) is controlled using a level sensor (not shown) to provide an internal freeboard space (810) that allows for the formation of a predetermined volume of liquid CO.sub.2-rich CO.sub.2 salted-out solvent phase and mixture (812) and (optionally) a WSWE-rich CO.sub.2 salted-out solvent phase and mixture (814) during CO.sub.2 SALLE operations. Moreover, said cannabis (802) immersed in water (807) is pretreated for a predetermined amount of time using 20 kHz or 40 kHz ultrasonic horn (815) possessing sufficient power to disrupt cellular structures contained in said cannabis (802) and to provide significant preheating of the water (807).
[0389] Step 2 (816): Said pressure vessel (808) is sealed, following which the mixture of (ultrasonically treated) cannabis (802) and water (806) is pressurized with dense phase CO.sub.2 (818) to acidify and provide an internal CO.sub.2 vapor pressure between 1 atm and 20 atm, establishing a tunable semi-aqueous solid-liquid extraction system comprising cannabis, water, and aqueous CO.sub.2. An internal pressure sensor and external CO.sub.2 pump (both not shown) preferably control the internal pressure of said pressure vessel (808).
[0390] Step 3 (820): Heating said tunable semi-aqueous solid-liquid extraction system to a decarboxylation temperature between 80° C. and 150° C., with CO.sub.2 acidification and CO.sub.2 vapor pressure of between 1 atm and 20 atm, for example, and held for a predetermined carbonic acid-catalyzed thermal decarboxylation time between 10 and 60 minutes. A conventional decarboxylation temperature and time schedule is based on known reaction conditions and rates to convert non-psychoactive extractable carboxylic acids to their neutral forms; for example, tetrahydrocannabinolic acid (THCA) to (psychoactive) tetrahydrocannabinol (THC), cannabidiolic acid (CBDA) to (synergistic) cannabidiol (CBD), and cannabigerolic acid (CBGA) to (synergistic) cannabigerol (CBG). For example, Perrotin-Brunel, H. et al., “Decarboxylation of Δ.sup.9-tetrahydrocannabinol: Kinetics and Molecular Modeling”, Journal of Molecular Structure 987 (2011) 67-73 (Perrotin-Brunel et al.),
[0391] Following Step 3 (820), said heated semi-aqueous solid-liquid extraction system containing decarboxylated and subcritical water extracted cannabis may be mixed with a WSWE compound or mixture under Step 4 (834) and processed sequentially under Steps 5-9 to produce a full-spectrum cannabis concentrate or tincture. Alternatively, Step 4 (834) may be skipped (836) and said heated semi-aqueous solid-liquid extraction system containing decarboxylated and subcritical water extracted cannabis may be cooled directly under Step 5 (838). Not adding a WSWE compound or mixture at this stage provides selectivity in the exemplary decarboxylation and extraction process. For example, absent a polar miscible WSWE compound, nonpolar liquid CO.sub.2 will selectively and predominantly extract nonpolar terpenoids and cannabinoids from the cooled semi-aqueous solid-liquid extraction system during subsequent CO.sub.2 SALLE concentration and recovery Steps 5-9.
[0392] Step 4 (834): Injecting and mixing (840) one or more water-soluble or water-emulsifiable compounds, and optional additives, into said heated semi-aqueous solid-liquid extraction system containing decarboxylated (psychoactive) and subcritical water extracted cannabis.
[0393] Step 5 (838): Cooling said heated semi-aqueous solid-liquid extraction system containing decarboxylated and subcritical water extracted cannabis, and WSWE/additive compounds, to a temperature between −40° C. and 30° C. Heat may be removed from the heated semi-aqueous solid-liquid extraction system using the exemplary solid-liquid mixing loop (822) used for heating, and comprising a recirculating pump (824), recirculating pipe (826), and fluid cooling means (842). Fluid cooling means (842) include any conventional technique, for example a chilled water heat exchanger, and which may be used with near-cryogenic CO.sub.2 aerosol injection. For example, following a pre-cooling stage using a chilled water heat exchanger to below 100° C., a vent valve (not shown) connected to the pressure vessel (808) may be opened to the atmosphere, whereupon a near-cryogenic dense phase CO.sub.2 (s.fwdarw.g) aerosol may be injected into the pre-cooled semi-aqueous solid-liquid extraction system through dense phase CO.sub.2 inlet (818) to further cool and saturate the solid-liquid solvent system with aqueous CO.sub.2. An internal temperature sensor (not shown) is preferably used in combination with said solid-liquid mixing loop, fluid cooling means (842), and CO.sub.2 aerosol injection (818).
[0394] Step 6 (844): Increasing dense phase CO.sub.2 pressure through dense phase CO.sub.2 inlet (818) to between 20 and 100 atm at a temperature between −40° C. and 30° C. to form a biphasic or multiphasic (if WSWE compounds are present) semi-aqueous solid-liquid extraction system. An internal pressure sensor and external CO.sub.2 pump (both not shown) preferably control the internal pressure of said pressure vessel (808).
[0395] Step 7 (846): Turbulently mixing said biphasic or multiphasic semi-aqueous solid-liquid extraction system using said mixing loop (622) for a predetermined time between 5 and 60 minutes to facilitate the extraction of decarboxylated cannabinoids and other extractables from cannabis (802). Turbulent mixing may be accomplished using the exemplary solid-liquid mixing loop (822), previously described, and preferably flowing liquid CO.sub.2-rich and WSWE-rich CO.sub.2 salted-out solvent mixtures or phases from the upper hemisphere (832) into the lower hemisphere (830). Alternative mixing means include ultrasonics, mechanical blade, and centrifuge drum.
[0396] Step 8 (848): Halting mixing to allow the biphasic or multiphasic semi-aqueous solid-liquid extraction system to stratify into distinct layers; a water-rich semi-aqueous phase (806), WSWE-rich CO.sub.2 salted-out solvent mixture or phase (814), and a liquid CO.sub.2-rich CO.sub.2 salted-out solvent mixture or phase (812) containing a portion of cannabis extracts. Following this, the CO.sub.2 salted-out solvent mixtures (i.e., liquid CO.sub.2-rich (812) and WSWE-rich (814) phases) containing decarboxylated (psychoactive) cannabis extracts are decanted (852) from said pressure vessel (808).
[0397] Step 9 (850): Desolvating said CO.sub.2 salted-out solvent mixtures (i.e., liquid CO.sub.2-rich (812) and WSWE-rich (814) phases) containing decarboxylated (psychoactive) cannabis extracts to concentrate and recover said psychoactive cannabis extracts as a concentrate or tincture, as described previously herein. Following this, dense phase CO.sub.2 pressurization, mixing, extraction, stratification, decanting, and desolvating Steps 6-9 may be repeated (854) as needed to recover cannabis extracts from the semi-aqueous solid-liquid solvent system.
[0398] The exemplary decarboxylation-extraction process described under Steps 1-9 may use dense phase CO.sub.2 under supercritical conditions, which provides additional selectivity during co-extraction and desolvation operations. Moreover, higher semi-aqueous solid-liquid extraction system temperatures may be used to enhance extraction efficiency. As such, the entire pressure-temperature operating window for providing pressurization, heating, and cooling processes during a decarboxylation-extraction process is a dense phase CO.sub.2 pressure between 1 atm and 340 atm and a semi-aqueous solid-liquid extraction system temperature between −40° C. and 300° C. More preferably, said dense phase CO.sub.2 is contacted with said semi-aqueous solid-liquid extraction system at a temperature between −20° C. and 150° C. and at a pressure between 1 atm and 150 atm. In addition, process intensification techniques such as microwave pre-treatment, ultrasonic processing, and centrifugation may be employed to optimize the decarboxylation-extraction process conditions and extract yields.
[0399] Still moreover, the decarboxylation-extraction process described under
[0400] Following this, the processed semi-aqueous extractant (referred to as “Raffinate”) is recycled or discharged to drain. The decarboxylated cannabis contained in said hot treatment pressure vessel system is removed and transferred to said second cold treatment pressure vessel system and processed using a CO.sub.2 SALLE method to extract and recover residual nonpolar compounds. Following this, exhaustively extracted and decarboxylated cannabis (referred to as “Marc”) is removed from the second cold treatment pressure vessel system and disposed of or recycled.
[0401] Finally, the exemplary decarboxylation-extraction process described under
[0402] Having described exemplary aspects of the present invention, and its usefulness for extracting beneficial compounds from a biomaterial, it can be understood that the present invention can be used in many other novel solid-liquid and liquid-liquid extraction applications. In this regard, Table 5 provides examples of use for the present invention.
TABLE-US-00005 TABLE 5 Examples of Use Method Description 1. CO.sub.2 Salting-out Assisted Liquid-Liquid Extraction (CO.sub.2 Dense phase CO.sub.2 (gas, liquid, or supercritical) is used to selectively SALLE) Method expand and salt-out one or more water-soluble or water- emulsifiable compounds containing one or more extractable substances from a semi-aqueous solution used in a solid-liquid or liquid-liquid extraction process. 2. A Method for Natural Products Extraction A plant material is extracted using a mixture of dense phase CO.sub.2 and a semi-aqueous phase containing one or more water-soluble or water-emulsifiable substances to extract, concentrate, and recover full-spectrum natural extracts including cannabinoids, terpenes, flavonoids, and carotenoids. 3. A Method for Food and Beverage Infusion An alcoholic beverage containing fermented ethanol and ethanol- soluble compounds such as natural beverage flavors is expanded and salted-out, dissolved into a dense phase CO.sub.2, and (optionally) used to co-extract one or more herbs or spices to form a natural, healthful, and flavorful infusion. 4. A Process for Desolvating a Liquid or Solid Extract from A near-cryogenic solid-gas spray method of the present invention Dense Phase CO.sub.2 for desolvating liquid and solid extracts from dense phase CO.sub.2. 5. A Method for Extracting Organic Compounds from a A fermentation broth is extracted using the present invention to Fermented Broth recover dissolved organics for medical and pharmaceutical uses. 6. A Method for Forming Water-Oil and Oil-Water A botanical extract mixture is partially oxygenated to form a water- Botanical Emulsions oil or oil-water emulsifying agent for formulating emulsions containing same. 7. Method and Apparatus for a Hybrid Water-CO.sub.2 A water-based extraction process is used as a primary extraction Extraction Process process in combination with a dense phase CO.sub.2 co-extraction process and followed by a CO.sub.2 SALLE process of the present invention to exhaustively or selectively extract a liquid or solid substance. 8. A Method for Alcohol Recovery from Aqueous Solutions Recovery of alcohol such as isopropanol and ethanol from an industrial wastewater or fermented liquid. 9. A Method for Environmental Sample Analysis Environmental samples such as plants, soils, animal tissues, and waters are extracted to recover pollutants such as dissolved or suspended oils, chelated metals, pesticides, and pharmaceutical drugs for in-situ or ex-situ instrumental analysis. 10. A Method for Concentrating and Analyzing an Extract Extracts produced by a solid-liquid or liquid-liquid extraction from a Solid-Liquid or Liquid-Liquid Extraction Process process are concentrated and analyzed using as analytical chemical process. 11. A Method for Decarboxylating and Extracting Cannabis Fresh or dried cannabis is decarboxylated and extracted using using Subcritical Water and CO.sub.2 subcritical water and a multiphasic CO.sub.2 SALLE process.
[0403] The present invention is useful for extracting, concentrating, and recovering one or more organic, inorganic, and ionic compounds from a liquid or solid substance. Said organic, inorganic, or ionic compounds may be useful, for example, as food, beverage, nutraceutical, pharmaceutical, or cosmetic additives. Said organic, inorganic, or ionic compounds may be useful, for example, as analytes in an environmental pollution assessment. Said liquid substances may be, for example, potable waters, water-based extractants, or industrial wastewaters. Said solid substances may be, for example, plants, vegetables, fruits, animal tissue, and contaminated soils.
[0404] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the title, headings, terms, and phrases used herein are not intended to limit the subject matter or scope; but rather, to provide an understandable description of the invention. The invention is composed of several sub-parts that serve a portion of the total functionality of the invention independently and contribute to system level functionality when combined with other parts of the invention. The terms “CO2” and “CO.sub.2” and carbon dioxide are interchangeable. The terms “natural product” and “natural substance” and “biomaterial” and “plant-based” and “botanical products” are interchangeable. The terms “bio-based” and “natural” are interchangeable. The terms “Hansen Solubility Parameter” and “HSP” and “solubility parameter” and “cohesion energy” and the symbol “δ” are interchangeable. The terms “extract” and “extractable substance” and “extractable material” and “extractable compound” and “analyte” are interchangeable. The terms “extraction vessel” and “pressure vessel” and “process vessel” and “extractor” are interchangeable. The term “CO.sub.2 SALLE” includes both CO.sub.2 salting-out and CO.sub.2 solvent expansion phenomena assisted liquid-liquid extraction. The terms “a” or “an”, as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising (i.e., open language). The term coupled, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically. Any element in a claim that does not explicitly state “means for” performing a specific function, or “step for” performing a specific function, is not to be interpreted as a “means” or “step” clause as specified in 35 U.S.C. Sec. 112, Parag. 6. In particular, the use of “step of” in the claims herein is not intended to invoke the provisions of 35 U.S.C. Sec. 112, Parag. 6.
[0405] Incorporation of Reference: All research papers, publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent appl. was specifically and individually indicated to be incorporated by reference.