GB2493943A - The extraction of cardol and cardanol from cashew nut shell liquid - Google Patents
The extraction of cardol and cardanol from cashew nut shell liquid Download PDFInfo
- Publication number
- GB2493943A GB2493943A GB1114622.2A GB201114622A GB2493943A GB 2493943 A GB2493943 A GB 2493943A GB 201114622 A GB201114622 A GB 201114622A GB 2493943 A GB2493943 A GB 2493943A
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- solvent
- text
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- cardanol
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
- B01D15/26—Selective adsorption, e.g. chromatography characterised by the separation mechanism
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
- B01D15/26—Selective adsorption, e.g. chromatography characterised by the separation mechanism
- B01D15/265—Adsorption chromatography
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
- B01D15/26—Selective adsorption, e.g. chromatography characterised by the separation mechanism
- B01D15/40—Selective adsorption, e.g. chromatography characterised by the separation mechanism using supercritical fluid as mobile phase or eluent
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07B—GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR
- C07B63/00—Purification; Separation; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/004—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by obtaining phenols from plant material or from animal material
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/70—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment
- C07C37/82—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment by solid-liquid treatment; by chemisorption
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/02—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring monocyclic with no unsaturation outside the aromatic ring
- C07C39/06—Alkylated phenols
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/02—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring monocyclic with no unsaturation outside the aromatic ring
- C07C39/08—Dihydroxy benzenes; Alkylated derivatives thereof
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/54—Improvements relating to the production of bulk chemicals using solvents, e.g. supercritical solvents or ionic liquids
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Botany (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
A method for extracting 2 phenolic compounds from a mixture essentially comprises: providing an inert adsorbing support loaded with the mixture; separating a first compound with a first solvent; and separating a second compound with a second solvent; characterised in that the first molecule to be extracted is that that has the smallest number of OH groups. The adsorbing support may be silica, alumina, montmonrillonite, magnesium silicate, aluminium silicate, zeolite, polystyrene beads, chitosoan or glass beads. For example, Cashew Nut Shell Liquid (CNSL) was tumbled onto Celite (RTM) to give a free flowing powder. This was packed into a separation vessel and extracted firstly with liquid carbon dioxide (giving cardanol) and secondly with supercritical carbon dioxide (giving cardol).
Description
A METHOD FOR SEPARATING COMPOUNDS HAVING SIMILAR STRUCTURES.
Field of the invention.
This invention relates to the supercritical fractionation of compounds of similar structure from mixtures, for example the separation of technical Cashew Nut Shell Liquid (CNSL) comprising cardol and cardanol.
Brief description of the prior art.
Cashew nut shell liquid (CNSL) is a by-product of the cashew nut industry. Two different types are available commercially: natural or solvent extracted CNSL, and technical CNSL.
Natural CNSL is extracted from the shells using a non polar solvent such as hexane or a non polar solvent alternative such as supercritical carbon dioxide as described for example in Shobha and Ravindranath (S.V.Shobha, B. Ravindranath, in J.Agric. Food.Chem. 1991, 39, 2214-2217). Natural CNSL consists mostly of anacardic acid (an alkenyl salicylic acid), cardol and cardanol. The composition of natural CNSL varies from batch to batch, and also by place of origin. Atypical composition comprises 65 wt% of anacardic acid, 20 wt% of cardol, 10 wt% of cardanol, the remainder being polymeric material.
Technical CNSL is extracted by roasting the shells or by any other heating methods.
Such heating process transforms (decarboxylates) anacardic acid into cardanol. The composition of technical CNSL also varies by batch, country of origin and heating method. A typical composition comprises 65 wt% of cardanol, and 15 wt% of cardol, the remainder being polymeric material.
Separation of the constituents in technical CNSL can be achieved by column chromatography at laboratory scale. That method is however not applicable for industrial scale applications.
I
Distillation techniques have been developed in order to separate the constituents.
They do not give pure products however. Indeed cardanol that is available commercially is not free from cardol given the close boiling points of the two compounds. The elevated heat required to distil cardanol induces polymerisation, thereby preventing the subsequent isolation of cardol. The polymerised residue after distillation is commercially available as Residol.
US-4352944 disclosed modifications of CNSL using an amine. This amine was used to create a Mannich salt with the cardol constituent. at distillation did not isolate pure cardanol.
US-7825284 disclosed a similar approach describing part of the distillation process using boric acid.
US-7781623 also disclosed a similar approach describing part of the distillation process using acetic anhydride.
Srinavasa Rao etal(P.Phani Kumar, R.Paramashivappa, P.J.Vithayayil, RV.Subba Rao, A.Srinavasa Rao, J.Agric.Food.Chem, 2002, 50, 4705-4708) reported a method to separate the constituents of technical CNSL using a mixture of ammonia and methanol, followed by extraction with hexane in order to isolate cardanol, and ethyl acetate/hexane in order to isolate cardol. This process was carried out on reaction scales up to 1kg with claimed efficiencies of 93-95%.
Supercritical carbon dioxide extraction with the use of an isopropyl alcohol co-solvent was reported in JP-5000979. It was shown to separate cardol and cardanol.
Cardanol was separated into the supercritical phase and cardol remained in the isopropyl alcohol residue phase.
Philip et al. (J.Y.N Philip, J.D.C.Francisco, E.S.Dey, J.Buchweishaija, L.LMkayula, L.Ye., in J.Agric.Food.Chem, 2008, 56, 9350-9354) have reported the use of supercritical carbon dioxide to separate anacardic acid from natural CNSL when adsorbed onto a solid support This method isolated pure anacardic acid but did not separate cardanol from cardol.
Summary of the invention.
It is an objective of the present invention to provide a simple and efficient method for separating compounds having a similar structure and different polarity from a mixture.
It is another objective of the present invention to separate cardol and cardanol from technical cashew nut shell liquid.
It is also an objective of the present invention to obtain cardol and cardanol in pure form.
The foregoing objectives have been realised as described in the independent claims.
Preferred embodiments are described in the dependent claims.
Detailed description of the invention.
Accordingly, the present invention discloses a method for extracting two or more compounds from a mixture comprising several compounds having a similar structure, said structure consisting of a phenol group carrying 0, 1, or 2 additional OH groups and at least one alkyl group having at least 5 carbon atoms, said method comprising the steps of: a) dissolving the compound in an inert solvent if it is in solid form or using it neat or dissolved in a solvent if it is in liquid form; b) providing an inert adsorbing; c) loading the dissolved or liquid compound of step a) onto the support of step b) d) separating the first molecule having a first structure with a first solvent having a first polarity until complete separation is achieved; e) separating the second molecule having a second structure with a second solvent having a second polarity until complete separation is achieved; f) repeating the process until all compounds have been separated, characterised in that the first compound to be extracted is that that has the smallest number of OH groups.
The mixture from which the compounds are fractionated is preferably selected from a naturally occurring mixtures, for example cashew nut shell liquid or other similar substances comprising different kinds of phenol groups.
The mixture to be separated needs to be adsorbed onto the support and therefore provided in liquid form. Mixtures that occur in solid form must be dissolved in a solvent. Mixtures that occur in liquid form can be used as such or may be dissolved in an organic solvent, for example acetone. The solvent can then be removed by rotary evaporation.
The inert adsorbing supports that can be used in the present invention can be either neutral, or basic or acidic and can be selected from any support material known in the art, but they must be inert towards the components of the mixture. They can for example be glass beads, but preferably they have a large surface area and therefore are provided in a finely grinded form or in a porous form.
The support can be selected from any porous mineral oxide material. It is typically selected from silica, alumina, montmonrillionite, magnesium silicate, aluminium silicate, zeolite, polystyrene beads, chitosan. Suitable support material can for example be selected from Celite S®, Celite 11 O®, Celite 209®, Celite 281 ®, Celite 503®, Celite 512M®, Celite 545®, Celite 545AW®, Celite 560®, Celite 577F®, Celite 535® all produced by Celite Corp., acid Alumina (Alumina A), basic Alumina (Alumina B), neutral Alumina (Alumina N), Ascarite® and Florisil® both produced by Sigma-Aldrich, Bentonite, Kaolinite, Fuller's Earth, produced by Sigma-Aldrich.
Preferably the porous support material has the following typical properties; -pores having a diameter ranging from 7.5 to 30 nm; -porosity ranging from 1 to 4 cm3 Ig; -specific surface area is not particularly limited, it typically ranges between 5 to 250 m2/g; and -an average particle diameter ranging from 1 to 150 pm.
The amount of loading of the compound onto the support is not very restricted as long as the loaded powder remains a free flowing powder. It ranges typically
S
between 5 wt% and 60 wt% based on the weight of the loaded powder. Preferably it ranges between 20 wt% and 55 wt% and more preferably between 30 wt% and 50 wt%.
The solvent that is used in the separation process is carbon dioxide in the liquid state or in the supercritical state, alone or in combination with a co-solvent. Preferably it is used alone and it is a major advantage of the present invention that the same solvent can be used under two different conditions to separate two compounds having different structures In a preferred embodiment according to the present invention, carbon dioxide is used alone for the full separation.
The first molecule to be separated, typically the molecule which has a single OH group, is separated first using carbon dioxide in liquid form, meaning that it has the lowest polarity. The separation is carried out at a temperature of less than 31 °C and at a pressure of less than 73 bars. Preferably the temperatures ranges between 0 °C and 20 °C, more preferably it is of about 5 °C. Preferably the pressure ranges between 55 bars and 70 bars, more preferably it is of about 65 bars.
The second molecule to be separated, typically the molecule which has 2 OH groups, is separated using carbon dioxide in the supercritical state, meaning that it has a higher polarity than in the liquid state. The separation reaction is carried out at a temperature higher than 31 °C and at a pressure higher than 73 bars. Preferably the temperature ranges between 31 °C and 200 °C, more preferably between 31 °C and 80 °C. Preferably the pressure ranges between 73 bars and 1100 bars, more preferably between 200 bars and 700 bars. Most preferably the temperature is of about 50 °C and the pressure is of about 500 bars.
The third molecule, if present, is separated by increasing the polarity of the separating solvent. This can be achieved by increasing the temperature and pressure with respect to the previous separating conditions, such as for example, a temperature of 100 °C and a pressure of 1100 bars.
Alternatively, it can be carried out by adding a co-solvent to the carbon dioxide and keeping the same temperature and pressure as in the previous separation. The co-solvent can be selected for example from ethanol or methanol.
A preferred embodiment according to the present invention discloses a method for separating cardol and cardanol from technical cashew nut shell liquid (CNSL) that comprises the steps of: a) optionally dissolving CNSL in an organic solvent; b) providing an inert adsorbing; c) loading neat CNSL or the dissolved compound of step a) onto the support of step b) d) separating cardanol with liquid dioxide at a temperature ranging between 0 and 20 C and under a pressure of from 55 to 70 bars until all cardanol has been separated; e) separating cardol with supercritical carbon dioxide at a temperature ranging between 31 and 200 C and under a pressure ranging between 200 and 700 bars until complete separation is achieved; The separated compounds find use in different applications. For example, the cardol and cardanol separated from cashew nut shell oil can be used in the fields of herbicides, antioxidants, UV protection.
Examples
Example 1
g of technical CNSL were tumbled onto 50 g of Celite 545® purchased from World Minerals at ambient temperature (20°C). The support had a surface area of 12 m2/g and a porosity of 0.015 cm3/g (Nl.Lulova, A.VKuzmkia, N.M.Koroleva, Chemistry and Tbchnoiogy of Fuels and Ois, volume 2, issue 9, pages 658-661). The resulting product was a slightly pink free flowing powder with no visible lumps. The mixture was cooled to 5°C overnight. 49.5g of this powder were packed into a lOOmI separation vessel and the extraction was carried out at a temperature of 5°C, and under a pressure of 65 bar, with a rate of 8g of carbon dioxide per minute, and for a period of time of 2 hours. 3.04 g of cardanol was isolated as yellow oil, with a purity of 98.6% by high performance liquid chromatography (HPLC).
The separation was continued using the same conditions for a further 4 hours. A further 5.53 g of cardanol was isolated as yellow oil, with a purity of 95.6% by HPLC.
The separation was continued using the same conditions for a further hour. A third portion, 0.389 g of a yellow oil was collected, with a purity of 81.6% by HPLC.
After this crossover fraction, the separation conditions were changed to a temperature of 50°C, a pressure of 500 bar, and a CO2 rate of 8 g per minute. The separation was carried out for a period of time of 1.5 hours. 1.32 g of cardol were isolated as viscous orange oil, in pure form by HALO.
The overall recovery of pure cardol compared to the theoretical yield was 77.87%.
The overall recovery of >95% pure cardanol compared to the theoretical yield was 95.6%.
Claims (1)
- <claim-text>CLAI MS.1. A method for extracting 2 or more compounds from compounds comprising several compounds having a similar structure, said structure consisting of a phenol moiety carrying 0, 1, or 2 additional OH groups and at least one alkyl group having at least 5 carbon atoms, said method comprising the steps of: a) dissolving the mixture in an organic solvent if it is in solid form or using it neat or dissolved in a solvent if it is in liquid form; b) providing an inert adsorbing support; c) loading the dissolved or liquid mixture of step a) onto the support of step b) d) separating the first molecule having a first structure with a first solvent having a first polarity until complete separation is achieved; e) separating the second molecule having a second structure with a second solvent having a second polarity until complete separation is achieved; f) repeating the process until all compounds have been extracted, characterised in that the first molecule to be extracted is that that has the smallest number of OH groups.</claim-text> <claim-text>2. The method of claim 1 wherein the organic solvent of step a) is selected from acetone, methanol.</claim-text> <claim-text>3. The method of claim 1 or claim 2 wherein the inert adsorbing support is selected from silica, alumina, montmonrillionite, magnesium silicate, aluminium silicate, zeolite, polystyrene beads, chitosan or glass beads.</claim-text> <claim-text>4. The method of any one of the preceding claims wherein the inert adsorbing support is porous and has a surface area ranging between 5 and 250 m2/g 5. The method of any one of the preceding claims wherein the solvent used in the separation is carbon dioxide.6. The method of claim 4 wherein the solvent additionally comprises an organic co-solvent. C)7. The method of any one of the preceding claims wherein the first molecule is separated at a temperature ranging between 0 and 20 C and under a pressure ranging between 55 and 70 bars.8. The method of any one of the preceding claims wherein the second molecule is separated at a temperature ranging between 31 and 200 C and under a pressure ranging between 73 and 1100 bars.9. The method of any one of the preceding claims wherein the starting material is cashew nut shell liquid and the separated compounds are cardanol and cardol.</claim-text>
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1114622.2A GB2493943A (en) | 2011-08-24 | 2011-08-24 | The extraction of cardol and cardanol from cashew nut shell liquid |
| PCT/EP2012/065774 WO2013026727A1 (en) | 2011-08-24 | 2012-08-11 | A method for separating compounds of similar structure. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1114622.2A GB2493943A (en) | 2011-08-24 | 2011-08-24 | The extraction of cardol and cardanol from cashew nut shell liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201114622D0 GB201114622D0 (en) | 2011-10-05 |
| GB2493943A true GB2493943A (en) | 2013-02-27 |
Family
ID=44800817
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1114622.2A Withdrawn GB2493943A (en) | 2011-08-24 | 2011-08-24 | The extraction of cardol and cardanol from cashew nut shell liquid |
Country Status (2)
| Country | Link |
|---|---|
| GB (1) | GB2493943A (en) |
| WO (1) | WO2013026727A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB201202381D0 (en) | 2012-02-13 | 2012-03-28 | Univ Bangor | Method for preparing a herbicidal compound |
| GB201505287D0 (en) | 2015-03-27 | 2015-05-13 | Bangor University And Croda Internat Plc | Method of seperating Mannosylerythitol Lipids |
| WO2020183422A1 (en) * | 2019-03-12 | 2020-09-17 | University Of The Witwatersrand, Johannesburg | Compounds having excited state intramolecular proton transfer (esipt) character for use in treating and/or preventing sunburn and/or preventing u.v. damage |
| EP4006006A1 (en) | 2020-11-27 | 2022-06-01 | Bridge Farm Nurseries Limited | Production of cannabidiol from hemp using subcritical liquid carbon dioxide |
| EP4242201A1 (en) * | 2022-03-11 | 2023-09-13 | Bridge Farm Nurseries Limited | Cannabinoids extraction and conversion |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06329536A (en) * | 1993-05-21 | 1994-11-29 | Mikimoto Pharmaceut Co Ltd | Active oxygen suppressive agent |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4352944A (en) | 1980-01-08 | 1982-10-05 | Minnesota Mining And Manufacturing Company | Treatment of cashew nut shell liquid |
| JPS59227270A (en) | 1983-06-06 | 1984-12-20 | Ajinomoto Co Inc | Production of soy sauce or liquid seasoning containing soup stock |
| JPH05979A (en) * | 1991-06-19 | 1993-01-08 | Tohoku Kako Kk | Method for separating and purifying cashew nutshell juice |
| DE102005017126A1 (en) | 2005-04-14 | 2006-10-19 | Cognis Ip Management Gmbh | Process for the preparation of cardanol (I) |
| DE102005017125A1 (en) | 2005-04-14 | 2006-10-19 | Cognis Ip Management Gmbh | Process for the preparation of cardanol (II) |
-
2011
- 2011-08-24 GB GB1114622.2A patent/GB2493943A/en not_active Withdrawn
-
2012
- 2012-08-11 WO PCT/EP2012/065774 patent/WO2013026727A1/en active Application Filing
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06329536A (en) * | 1993-05-21 | 1994-11-29 | Mikimoto Pharmaceut Co Ltd | Active oxygen suppressive agent |
Non-Patent Citations (5)
| Title |
|---|
| "Isolation of Anarcardic Acid...", J. Agric. Food Chem. 2008, 56, 9350-9354, Philip et al. * |
| "Long-chain phenols", Journal of Chromatography, 166, 1978, 159-172, Tyman. * |
| "Long-chain phenols", Journal of Chromatography, 235, 1982, 149-164, Tyman et al. * |
| "Molluscicides from the Cashew...", J. Agric. Food Chem. 1986, 34, 970-973, Kubo et al. * |
| "Practical Liquid Chromatographic...", Lipids, vol 21, no 3, 1986, 241-246, Sood et al. * |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201114622D0 (en) | 2011-10-05 |
| WO2013026727A1 (en) | 2013-02-28 |
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