A method for extracting and separating linalool

Abstract

The present invention relates to the field of plant extraction technology, specifically, to a method for extracting and isolating linalool. The method comprises the following steps: 1) mixing an ionic liquid aqueous solution with camphor tree leaf powder, centrifuging, and collecting the supernatant to obtain an extract; 2) adding a polymerization inhibitor and an azeotrope to the extract, and concentrating under reduced pressure to obtain a mixture A; 3) rectifying the mixture A under reduced pressure, collecting the coolant, and obtaining a mixture B; 4) adding the mixture B to an organic solvent and an aqueous solution containing an alkaline substance, stirring, and separating the liquids to obtain an organic phase; and 5) concentrating the organic phase to obtain a refined linalool product. This method for extracting and isolating linalool improves the yield of active components, as well as the isolation yield and purity of linalool. It has high separation efficiency, eliminates the need for column chromatography and microwave-ultrasound separation, is simple to operate, and is suitable for industrial production, with broad application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of plant extraction, and in particular to a method for extracting and separating linalool. Background Art

[0002] Linalool, also known as linalool, is a precious natural resource whose efficient extraction and sustainable utilization have become a focus of industry attention as global demand for natural fragrances, medicinal ingredients, and high-value-added plant extracts continues to grow. Traditional linalool extraction processes suffer from low efficiency, significant resource waste, and environmental pollution. During component separation, linalool and other components have similar solubility and polarity, making column chromatography difficult to isolate high-purity linalool. Heating and distillation can cause self-polymerization and product deterioration, making large-scale production difficult. Therefore, technological innovation is urgently needed to achieve green, efficient, and sustainable processes for extracting and separating linalool's active components. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems of low extraction yield of active components, low separation yield and purity of linalool, and easy self-aggregation and deterioration of linalool during separation, thereby providing a method for extracting and separating linalool. The method avoids quality degradation and mass loss of linalool due to self-aggregation during the separation process, improves the yield of active components, and also improves the separation yield and purity of linalool. At the same time, the method for extracting and separating linalool is environmentally friendly, has high separation efficiency, does not require column chromatography and microwave ultrasonic separation, is simple to operate, is suitable for industrial production, and has broad application prospects.

[0004] In order to achieve the above objectives, in a first aspect, the present invention provides a method for extracting and separating linalool, the method comprising the following steps:

[0005] 1) mixing the ionic liquid aqueous solution with camphor tree leaf powder, centrifuging, and collecting the supernatant to obtain an extract;

[0006] 2) adding a polymerization inhibitor and an azeotrope to the extract, and concentrating under reduced pressure to obtain a mixture A;

[0007] 3) distilling the mixture A under reduced pressure, collecting the cooling liquid, and obtaining a mixture B;

[0008] 4) adding the mixture B to an organic solvent and an aqueous solution containing an alkaline substance, stirring, and separating the liquids to obtain an organic phase;

[0009] 5) Concentrate the organic phase to obtain the refined linalool.

[0010] Preferably, in step 1), the ionic liquid is 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide.

[0011] Preferably, the mass fraction of the ionic liquid aqueous solution is 5-20%.

[0012] Preferably, the mass ratio of the ionic liquid aqueous solution to the camphor tree leaf powder is 9-11:1.

[0013] Preferably, in step 1), the mixing conditions include: temperature of 15-35° C., stirring rate of 150-300 rpm, and stirring time of 8-12 h.

[0014] Preferably, the centrifugal conditions include: a rotation speed of 1800-2000 rpm and a time of 1-2 h.

[0015] Preferably, in step 2), the polymerization inhibitor is phenol.

[0016] Preferably, the azeotrope is phenol.

[0017] Preferably, the mass ratio of the extract to phenol is 1:1-3.

[0018] Preferably, in step 2), the conditions for the reduced pressure concentration include: a temperature of 30-45° C. and a pressure of 35-30 mmHg.

[0019] Preferably, in step 3), the conditions for the vacuum distillation include: a temperature of 80-95° C. and a pressure of 35-30 mmHg.

[0020] Preferably, in step 4), the organic solvent is selected from one or two or more of ethyl acetate, dichloromethane and petroleum ether.

[0021] Preferably, the alkaline substance is selected from one or two or more of sodium hydroxide, potassium hydroxide and calcium hydroxide.

[0022] Preferably, the molar ratio of the alkaline substance to phenol is 1-2:1.

[0023] Preferably, the stirring conditions include: a stirring rate of 150-300 rpm and a stirring time of 0.5-2 h.

[0024] Preferably, in step 5), the concentration conditions include: temperature of 40-50° C. and time of 1-3 h.

[0025] In a second aspect, the present invention provides linalool obtained by the extraction and separation method described in the first aspect.

[0026] In the above technical solution, the extraction and separation method of linalool of the present invention uses 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide as an extractant to increase the extraction yield of the active component, thereby improving the extraction efficiency of linalool. The S=O and CF bonds in the 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ion have high bond energy and strong polarity, and strong chemical stability. These polar bonds can interact through hydrogen bonds and dipole-dipole interactions. The 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ion can bind to the alcohols, ketones, and sesquiterpenes in linalool, enhancing solubility. On the other hand, 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide has a spatially symmetrical structure and can bind to aromatic hydrocarbons through π-π interactions, enhancing its solubility for aromatic hydrocarbon compounds, thereby improving the extraction yield of the active component.

[0027] The present method for extracting and separating linalool also utilizes phenol to form an azeotrope with linalool, further improving the separation yield and purity of linalool. Phenol and linalool have similar boiling points, and hydrogen bonds are formed between them through the interaction of their intermolecular polar functional groups. The allyl hydroxyl group (-OH) in linalool acts as a hydrogen bond donor, providing a polarized hydrogen atom that combines with the lone pair of electrons in phenol to form hydrogen bonds. This allows linalool and phenol to form an azeotropic system, facilitating the extraction and separation of linalool. Furthermore, the inhibition of phenol prevents self-polymerization of linalool during heating, thus preventing degradation and loss of linalool quality due to self-polymerization during the separation process.

[0028] Moreover, the extraction and separation method of linalool of the present invention is green and environmentally friendly, has high separation efficiency, does not require column chromatography and microwave ultrasonic separation, is simple to operate, and is suitable for industrial production.

[0029] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0031] Figure 1 This is the H NMR spectrum of linalool prepared in Example 1 of the present invention;

[0032] Figure 2 This is the appearance of the linalool prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0033] The following is a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0034] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0035] In a first aspect, the present invention provides a method for extracting and separating linalool, the method comprising the following steps:

[0036] 1) mixing the ionic liquid aqueous solution with camphor tree leaf powder, centrifuging, and collecting the supernatant to obtain an extract;

[0037] 2) adding a polymerization inhibitor and an azeotrope to the extract, and concentrating under reduced pressure to obtain a mixture A;

[0038] 3) distilling the mixture A under reduced pressure, collecting the cooling liquid, and obtaining a mixture B;

[0039] 4) adding the mixture B to an organic solvent and an aqueous solution containing an alkaline substance, stirring, and separating the liquids to obtain an organic phase;

[0040] 5) Concentrate the organic phase to obtain the refined linalool.

[0041] In a preferred embodiment of the present invention, in order to improve the extraction yield of the active component, in step 1), the ionic liquid is 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide.

[0042] In a preferred embodiment of the present invention, in order to improve the extraction yield of the active component, the mass fraction of the ionic liquid aqueous solution is increased to 5-20%.

[0043] In a preferred embodiment of the present invention, in order to improve the extraction yield of the active component, the ratio of the ionic liquid aqueous solution to the camphor tree leaf powder is 9-11:1, preferably 10:1, and can also be 9:1, 9.5:1, 10.5:1, 11:1, etc.

[0044] In a preferred embodiment of the present invention, in order to improve the extraction yield of active components in camphor leaves, in step 1), the mixing conditions include: temperature of 15-35°C, stirring rate of 150-300rpm, and stirring time of 8-12h, for example, the temperature can be 25°C, the stirring rate is 200rpm, and the time is 10h; the temperature is 15°C, the stirring rate is 150rpm, and the time is 8h; the temperature is 20°C, the stirring rate is 250rpm, and the time is 9h; the temperature is 30°C, the stirring rate is 280rpm, and the time is 11h; the temperature is 35°C, the stirring rate is 250rpm, and the time is 10h; the temperature is 32°C, the stirring rate is 300rpm, and the time is 12h, etc.

[0045] In a preferred embodiment of the present invention, the centrifugal conditions include: a rotation speed of 1800-2000 rpm and a time of 1-2 h; for example, a rotation speed of 1800 rpm and a time of 1 h; a rotation speed of 1900 rpm and a time of 1.5 h; a rotation speed of 2000 rpm and a time of 2 h; a rotation speed of 1800 rpm and a time of 1.5 h, etc.

[0046] In a preferred embodiment of the present invention, in order to prevent linalool from self-polymerizing during the heating process, in step 2), the polymerization inhibitor is phenol.

[0047] In a preferred embodiment of the present invention, in order to improve the separation efficiency of linalool, linalool and phenol have similar boiling points and can form hydrogen bonds, so that the azeotropic effect between the two is good; at the same time, phenol can be separated from the crude product obtained by azeotropy by washing with an alkaline aqueous solution, and the extraction and separation of the product is convenient, and the azeotrope is phenol.

[0048] In a preferred embodiment of the present invention, in order to obtain better separation efficiency, the mass ratio of the extract to phenol is 1:1-3, preferably 1:2; it can also be 1:1, 1:3 or 1:2.5.

[0049] In a preferred embodiment of the present invention, in step 2), the conditions for the reduced pressure concentration include: a temperature of 30-45° C. and a pressure of 35-30 mmHg.

[0050] In a preferred embodiment of the present invention, in step 3), the conditions of the vacuum distillation include: a temperature of 80-95° C. and a pressure of 35-30 mmHg.

[0051] In a preferred embodiment of the present invention, in step 4), the organic solvent is selected from one or two or more of ethyl acetate, dichloromethane and petroleum ether.

[0052] In a preferred embodiment of the present invention, the alkaline substance is selected from one or two or more of sodium hydroxide, potassium hydroxide and calcium hydroxide.

[0053] In a preferred embodiment of the present invention, the molar ratio of the alkaline substance to phenol is 1-2:1.

[0054] In a preferred embodiment of the present invention, the stirring conditions include: a stirring rate of 150-300 rpm, a stirring time of 0.5-2 h, preferably a stirring rate of 200 rpm, a stirring time of 1 h; a stirring rate of 150 rpm, a stirring time of 0.5 h; a stirring rate of 180 rpm, a stirring time of 1 h; a stirring rate of 250 rpm, a stirring time of 1.5 h; a stirring rate of 300 rpm, a stirring time of 2 h, etc.

[0055] In a preferred embodiment of the present invention, in step 5), the concentration conditions include: temperature of 40-50°C, time of 1-3 hours, preferably temperature of 45°C, time of 2 hours; temperature of 40°C, time of 1 hour; temperature of 45°C, time of 1.5 hours; temperature of 50°C, time of 2.5 hours; temperature of 50°C, time of 3 hours, etc.

[0056] In a second aspect, the present invention provides linalool obtained by the extraction and separation method described in the first aspect.

[0057] In a preferred embodiment of the present invention, the room temperature is 15-30°C.

[0058] The present invention will be described in detail below by way of examples. In the following examples, the drugs and pharmaceuticals are all conventional commercial products.

[0059] Example 1

[0060] (1) Add 1000 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 1000 g of water to a reaction flask, stir to obtain an ionic liquid aqueous solution, mix 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, and mechanically stir at a stirring rate of 200 rpm at room temperature for 10 hours. The stirred mixture is centrifuged at a speed of 2000 rpm for 1 hour, and the liquid is collected to obtain an extract;

[0061] (2) 100 g of phenol was added to the above extract, and the water was separated by vacuum concentration at 40°C and 35 mmHg to obtain a mixture A (mass 1150 g) of a crude extract containing linalool and phenol, with a crude extract yield of 5%;

[0062] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0063] (4) Add 200 g of ethyl acetate and 86 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the layers, and collect the ethyl acetate phase;

[0064] (5) The ethyl acetate phase was concentrated at 45°C for 2 h to obtain 30 g of linalool with a purity of about 99.7%; the yield of pure linalool was 3.0%.

[0065] The crude product yield was calculated as follows: (1150 g - 100 g phenol - 1000 g ionic liquid) / 1000 g camphor tree leaf powder = 5%.

[0066] Calculation method for pure product yield: (30 grams of pure product) / 1000 grams of camphor tree leaf powder = 3%.

[0067] The nuclear magnetic hydrogen spectrum of the fine linalool is as follows Figure 1 As shown, the data is as follows:

[0068] 1 HNMR (600 MHz, ) δ 5.86 – 5.75 (m, 1H), 5.14 – 5.05 (m, 1H), 5.05 –4.97 (m, 1H), 4.95 – 4.84 (m, 1H), 1.96 – 1.78 (m, 2H), 1.59 (d, J = 4.9 Hz,3H), 1.51 (d, J = 8.2 Hz, 3H), 1.39 – 1.32 (m, 2H), 1.12 – 1.09 (m, 3H).

[0069] Depend on Figure 2 From the appearance of the linalool, it can be seen that the linalool prepared by the present invention is a transparent liquid without obvious foreign matter and impurities, and is very pure.

[0070] Example 2

[0071] In this example, the concentration of the ionic liquid aqueous solution was reduced on the basis of Example 1, and the final crude extract yield was slightly reduced, and the purity of linalool was slightly reduced.

[0072] (1) Add 800 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 1000 g of water to a reaction flask, stir to obtain an ionic liquid aqueous solution, mix 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, and mechanically stir at a stirring rate of 200 rpm at room temperature for 10 hours. The stirred mixture is centrifuged at a speed of 2000 rpm for 1 hour, and the liquid is collected to obtain an extract;

[0073] (2) 100 g of phenol was added to the extract, and the water was separated by vacuum concentration at 40°C and 35 mmHg to obtain a mixture A (mass 946 g) of a crude extract containing linalool and phenol. The yield of the crude extract was 4.6%.

[0074] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0075] (4) Add 200 g of ethyl acetate and 86 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the layers, and collect the ethyl acetate phase;

[0076] (5) The ethyl acetate phase was concentrated at 45°C for 2 h to obtain 26 g of linalool with a purity of 99.6%. The yield of pure linalool was 2.6%.

[0077] Example 3

[0078] In this example, the concentration of the ionic liquid aqueous solution was increased on the basis of Example 1, and the yield of the crude extract was slightly improved, while the purity of linalool was reduced.

[0079] (1) Adding 1000 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 900 g of water to a reaction flask, stirring to obtain an ionic liquid aqueous solution; mixing 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, mechanically stirring the mixture at a stirring rate of 200 rpm at room temperature for 10 hours, centrifuging the stirred mixture at a speed of 2000 rpm for 1 hour, and collecting the liquid to obtain an extract;

[0080] (2) 100 g of phenol was added to the extract, and the water was separated by vacuum concentration at 40°C and 35 mmHg to obtain a mixture A (mass 1153 g) of a crude extract containing linalool and phenol. The yield of the crude extract was 5.3%.

[0081] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0082] (4) Add 200 g of ethyl acetate and 86 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the layers, and collect the ethyl acetate phase;

[0083] (5) The ethyl acetate phase was concentrated at 45°C for 2 h to obtain 32 g of linalool with a purity of approximately 97.3%. The yield of pure linalool was 3.2%.

[0084] Example 4

[0085] In this example, the amount of phenol was increased to 200 g based on Example 1, which slightly improved the yield of the crude extract and reduced the purity of linalool.

[0086] (1) Adding 1000 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 1000 g of water to a reaction flask, stirring to obtain an ionic liquid aqueous solution; mixing 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, mechanically stirring the mixture at a stirring rate of 200 rpm at room temperature for 10 hours, centrifuging the stirred mixture at a speed of 2000 rpm for 1 hour, and collecting the liquid to obtain an extract;

[0087] (2) Add 200 g of phenol to the extract, and concentrate under reduced pressure at 40°C and 35 mmHg to separate water, obtaining a mixture A (mass 1252 g) of a crude extract containing linalool and phenol, with a crude extract yield of 5.2%;

[0088] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0089] (4) Add 200 g of ethyl acetate and 172 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the layers, and collect the ethyl acetate phase;

[0090] (5) The ethyl acetate phase was concentrated at 45°C for 2 hours to obtain 31 g of linalool with a purity of 98.1%. The yield of pure linalool was 3.1%.

[0091] Example 5

[0092] In this example, the amount of sodium hydroxide was increased on the basis of Example 1, and the yield of linalool was slightly decreased, while the purity was slightly improved.

[0093] (1) Adding 1000 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 1000 g of water to a reaction flask, stirring to obtain an ionic liquid aqueous solution; mixing 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, mechanically stirring the mixture at a stirring rate of 200 rpm at room temperature for 10 hours, centrifuging the stirred mixture at a speed of 2000 rpm for 1 hour, and collecting the liquid to obtain an extract;

[0094] (2) Add 100 g of phenol to the extract, and concentrate under reduced pressure at 40°C and 35 mmHg to separate water, to obtain a mixture A (mass 1150 g) containing the crude extract and phenol, with a crude extract yield of 5%;

[0095] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0096] (4) Add 200 g of ethyl acetate and 172 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the layers, and collect the ethyl acetate phase;

[0097] (5) The ethyl acetate phase was concentrated at 45°C for 2 h to obtain 27 g of linalool with a purity of 99.9%. The yield of pure linalool was 2.7%.

[0098] Example 6

[0099] In this example, based on Example 1, the extraction solvent was replaced with petroleum ether, and the yield of linalool decreased slightly.

[0100] (1) Add 1000 g of ionic liquid 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide and 1000 g of water to a reaction flask, stir to obtain an ionic liquid aqueous solution, mix 1000 g of camphor tree leaf powder with the ionic liquid aqueous solution, and mechanically stir at a stirring rate of 200 rpm at room temperature for 10 hours. The stirred mixture is centrifuged at a speed of 2000 rpm for 1 hour to obtain an extract;

[0101] (2) 100 g of phenol was added to the extract, and the water was separated by vacuum concentration at 40°C and 35 mmHg to obtain a mixture A (mass 1150 g) of a crude extract containing linalool and phenol. The yield of the crude extract was 5%.

[0102] (3) Mixture A was subjected to vacuum distillation at 85°C and 30 mmHg, and the cooling liquid was collected to obtain a mixture B containing phenol and linalool;

[0103] (4) Add 200 g of petroleum ether and 172 g of 50% sodium hydroxide aqueous solution to mixture B, stir, separate the liquids, and collect the petroleum ether phase;

[0104] (5) The petroleum ether phase was concentrated at 50°C for 1 h to obtain 28 g of linalool with a purity of 99.7%. The yield of pure linalool was 2.8%.

[0105] Comparative Example 1

[0106] The method of Example 1 was followed, except that 1-hexyl-3-methylimidazole bis(trifluoromethanesulfonyl)imide was replaced with tributyloctylphosphonium bromide. Other conditions remained unchanged. The crude extract yield was 2.3%, and 11 g of linalool was obtained with a purity of 99.5%.

[0107] Table 1

[0108]

[0109] From the above data, it can be seen that the yield of the crude extract containing linalool extracted by the method of the present invention is higher, and thus the yield and yield of the obtained linalool fine product are also higher; and the operation is simple, no special equipment is required to meet the process requirements, and it is suitable for industrial production.

[0110] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0111] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0112] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for extracting and separating linalool, characterized in that: The extraction and separation method comprises the following steps: 1) mixing the ionic liquid aqueous solution with camphor tree leaf powder, centrifuging, and collecting the supernatant to obtain an extract; 2) adding a polymerization inhibitor and an azeotrope to the extract, and concentrating under reduced pressure to obtain a mixture A; 3) distilling the mixture A under reduced pressure, collecting the cooling liquid, and obtaining a mixture B; 4) adding the mixture B to an organic solvent and an aqueous solution containing an alkaline substance, stirring, and separating the liquids to obtain an organic phase; 5) Concentrating the organic phase to obtain the refined linalool; In step 1), the ionic liquid is 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide; In step 2), the polymerization inhibitor is phenol; The azeotrope is phenol; In step 4), the organic solvent is ethyl acetate or petroleum ether; The alkaline substance is sodium hydroxide.

2. The extraction and separation method according to claim 1, wherein The mass fraction of the ionic liquid aqueous solution is 5-20%; and / or, The ratio of the ionic liquid aqueous solution to the camphor tree leaf powder is 9-11:

1.

3. The extraction and separation method according to claim 1 or 2, characterized in that In step 1), the mixing conditions include: temperature of 15-35° C., stirring rate of 150-300 rpm, stirring time of 8-12 h; and / or, The centrifugal conditions include: a rotation speed of 1800-2000 rpm and a time of 1-2 hours.

4. The extraction and separation method according to claim 1, wherein The mass ratio of the extract to phenol is 1:1-3.

5. The extraction and separation method according to claim 1, characterized in that In step 2), the conditions for the reduced pressure concentration include: a temperature of 30-45° C. and a pressure of 35-30 mmHg.

6. The extraction and separation method according to claim 1, characterized in that In step 3), the conditions for the vacuum distillation include: a temperature of 80-95° C. and a pressure of 35-30 mmHg.

7. The extraction and separation method according to claim 1, characterized in that In step 4), the molar ratio of the alkaline substance to phenol is 1-2:1; and / or, The stirring conditions include: a stirring rate of 150-300 rpm and a stirring time of 0.5-2 h.

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