Sebacic acid extracting and refining method and product

Abstract

The invention discloses a sebacic acid extracting and refining method and a product, and the method comprises the following steps: (1) filtering sebacic acid fermentation liquor or treatment liquor thereof, and carrying out acidification crystallization, solid-liquid separation and drying on filtrate to obtain a sebacic acid crude product; and (2) mixing and dissolving the sebacic acid crude product and an alcohol organic solvent at the temperature of 50-97 DEG C, performing decoloration treatment to obtain a decoloration solution with the turbidity of less than 5NTU, performing crystallization treatment on the decoloration solution, and performing solid-liquid separation to obtain a sebacic acid product. The extraction and refining method provided by the invention can remove a large amount of pigments and impurities to obtain a decolorized solution with turbidity less than 5NTU, so that the quality, purity, chromaticity and the like of a sebacic acid product are improved, and the extraction and refining method is simple and easy to operate and is beneficial to large-scale industrial production.

Description

Technical Field

[0001] The invention relates to a method for extracting and refining sebacic acid and a product thereof. Background Art

[0002] Sebacic acid (or deca-carbon long-chain dibasic acid) refers to an aliphatic dicarboxylic acid containing 10 carbon atoms in the carbon chain. It is a type of fine chemical product with important and extensive industrial uses. It is an important raw material for high-performance polyamide textiles, high-performance polyamide engineering plastics, synthetic high-grade fragrances, high-grade polyamide hot-melt adhesives, high-temperature electrolytes, cold-resistant plasticizers, high-grade lubricants, high-grade paints and coatings, medicines and pesticides in the chemical industry.

[0003] The chemical synthesis of sebacic acid is mainly to hydrolyze castor oil under the action of a catalyst to produce ricinoleic acid, and then to obtain it by high temperature and alkaline cracking. The biological fermentation method can produce sebacic acid using petroleum byproduct wax oil, alkanes, fatty acids or their derivatives as raw materials, and ferment sebacic acid under low temperature and low pressure using the unique oxidation ability of microorganisms and the action of microbial intracellular enzymes. Therefore, it has the advantages of a wide source of raw materials, simple production process, mild production conditions, etc., and has obvious advantages over traditional chemical synthesis methods.

[0004] When using biological fermentation to produce sebacic acid, the fermentation liquid obtained usually contains multiphase components such as water phase, oil phase (such as residual oil raw materials) and solid phase (such as microbial cells, residual protein, etc.), and there is also emulsification in the water phase and the oil phase. The complex fermentation liquid system increases the difficulty of subsequent extraction and purification of sebacic acid. If the sebacic acid product has low purity, high impurity content such as ash and moisture, it is difficult to meet the requirements of high-end polymer products for monomer raw materials. Existing research is also mostly focused on the fermentation link, and there is no systematic study on the subsequent purification process of the fermentation liquid. Therefore, it is urgent to develop a biological method sebacic acid product with lower impurity content and higher product performance. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for extracting and refining sebacic acid, which comprises:

[0006] (1) filtering the sebacic acid fermentation broth or the treated broth thereof, acidifying and crystallizing the filtrate, performing solid-liquid separation, and drying to obtain a crude sebacic acid product;

[0007] (2) The crude sebacic acid product is mixed and dissolved with an alcohol organic solvent at a temperature of 50 to 97° C., and then decolorized to obtain a decolorized solution with a turbidity of less than 5 NTU. The decolorized solution is crystallized and solid-liquid separated to obtain a sebacic acid product.

[0008] In one embodiment, before performing step (1), the pH value of the sebacic acid fermentation broth is 2-12, further 4-12, further 4-9, further 4-6.5 or 7.3-8.5, further 5-6.5 or 7.5-8.3.

[0009] In the present invention, the sebacic acid fermentation broth in step (1) is obtained by biological method, specifically by using decane, ten-carbon fatty acids and their derivatives as substrates and using a microbial fermentation method. The microorganism can generate sebacic acid as long as it can oxidize the terminal methyl groups of alkanes, fatty acids and fatty acid derivatives to carboxyl groups. In some preferred embodiments, the fermentation substrate is decane.

[0010] The treated liquid of the fermentation liquid is a liquid obtained by removing one or more components other than sebacic acid or sebacic acid salt in the fermentation liquid or reducing the content thereof.

[0011] In some embodiments, the sebacic acid fermentation broth is obtained by the following steps: fermenting and culturing sebacic acid-producing microorganisms, controlling the pH value of the fermentation system to be above 3.0 during the bacterial growth phase, and the pH value of the fermentation system to be 4-9 during the conversion phase.

[0012] In some preferred embodiments, the pH value of the fermentation system during the bacterial growth phase is preferably 3.5 to 6.5.

[0013] In some preferred embodiments, the pH value of the fermentation system during the conversion phase is preferably 4.0 to 6.8, more preferably 5.0 to 6.5.

[0014] Alternatively, in some other preferred embodiments, the pH value of the fermentation system during the conversion phase is preferably 7.0-9, more preferably 7.0-8.5, and even more preferably 7.5-8.5.

[0015] In some embodiments, the fermentation temperature is 28-32° C., the fermentation air volume is 0.3-1.0 vvm, the fermentation pressure is 0.05-0.14 MPa, and the inoculation amount is 10-30% (v / v).

[0016] In some embodiments, the sebacic acid-producing microorganism comprises Candida viswanathii, Candida tropicalis, or Candida sake.

[0017] In some preferred embodiments, when the optical density (OD620) of the fermentation system is above 0.5 (30-fold dilution), such as 0.5, 0.6, 0.7, 0.8, etc., the pH value of the fermentation system is controlled within the aforementioned range.

[0018] In some preferred embodiments, the pH value of the terminated fermentation broth of sebacic acid is adjusted so that before step (1) is performed, a sebacic acid fermentation broth or a treated broth thereof that satisfies the above pH range is obtained.

[0019] In some preferred embodiments, the pH value of the terminated fermentation broth of sebacic acid is 4-9.

[0020] In some embodiments, the filtration in step (1) is membrane filtration, which can be used to remove impurities such as bacteria and large proteins in the fermentation broth or its treated liquid.

[0021] In some embodiments, the membrane filtration temperature is controlled at 45-95°C.

[0022] The inventors of the present invention have found in their research that the membrane pH value of the sebacic acid fermentation broth or its treated liquid will affect the turbidity of the decolorized liquid in the refining stage. If the membrane pH value is too low, the sebacic acid in the fermentation broth will still exist in the form of a monomer, the membrane permeability will be low, the membrane passing time will be long, and the bacteria will be broken into small molecules by the membrane circulation pump, resulting in excessive turbidity of the decolorized liquid, which will further affect the chromaticity, ash content, nitrogen content and other indicators of the final product.

[0023] In some embodiments, preferably, before filtering in step (1), the pH value of the sebacic acid fermentation broth or its treated broth is adjusted to above 7, further to above 8, such as 8.2, 8.5, 8.8, 9.0, etc.

[0024] In some embodiments, the filtration membrane used in the membrane filtration in step (1) may be a ceramic membrane, a metal membrane, a hollow fiber membrane or a plate membrane.

[0025] In some embodiments, preferably, the pore size of the filter membrane is 0.01 to 0.5 μm, further 0.05 to 0.1 μm.

[0026] In some embodiments, when a ceramic membrane is used to perform the membrane filtration in step (1), the operating pressure is controlled to be 0.1 to 0.6 MPa, and further 0.2 to 0.4 MPa.

[0027] In some preferred embodiments, step (1) includes the following steps: adjusting the pH value of the sebacic acid fermentation liquid or its treated liquid to above 7, heating it to 45-95°C, and then filtering the bacteria with a ceramic membrane while hot, controlling the operating pressure to 0.1-0.6 MPa, and the pore size of the ceramic membrane to 0.01-0.5 um to obtain a filtrate, and then cooling the filtrate for crystallization, solid-liquid separation, and drying to obtain a crude sebacic acid product.

[0028] In some embodiments, the acidification crystallization in step (1) includes: adjusting the pH value of the filtrate to 2-4, heating the filtrate to 80-110°C, further keeping the filtrate at 90-98°C for ≥30 min, and then cooling the filtrate to 30-40°C.

[0029] In the present invention, the acid used to adjust the pH value of the filtrate includes an inorganic acid and / or an organic acid, such as sulfuric acid, hydrochloric acid, nitric acid, acetic acid, oxalic acid, phosphoric acid and trifluoromethanesulfonic acid or a mixed acid containing at least two of them.

[0030] In some embodiments, solid-liquid separation may include filtration, centrifugal separation, such as plate and frame filtration, chamber filtration, centrifugal filtration, vacuum negative pressure filtration, etc.

[0031] In some specific embodiments, in step (2), the crude sebacic acid is mixed and dissolved with an alcohol organic solvent at a temperature of 50-75°C, and further at a temperature of 55-62°C.

[0032] In some embodiments, in step (2), the mass ratio of crude sebacic acid to alcohol organic solvent is 1:(2-6), further 1:(3-5), for example 1:3.2, 1:3.5, 1:4, 1:4.5, 1:5.5, etc.

[0033] In some embodiments, the alcohol organic solvent includes a monohydric alcohol or a dihydric alcohol having 1 to 4 carbon atoms, and further includes one or a combination of methanol, ethanol, n-butanol, and isopropanol.

[0034] Preferably, the purity of the alcohol organic solvent is ≥95%, further ≥97%, and further ≥99%.

[0035] In some embodiments, in step (2), activated carbon is used for the decolorization treatment.

[0036] The inventors of the present invention have found in their research that the iodine value and dosage of activated carbon will affect the turbidity of the decolorized liquid in the refining stage. If the iodine value is too small and the activated carbon cannot completely adsorb impurities in the membrane permeate at the same dosage, the turbidity of the decolorized liquid will be larger, thereby affecting the chromaticity, ash content, nitrogen content and other indicators of the final product.

[0037] Preferably, the iodine value of the activated carbon is 400 or more, further 550 or more, further 600-1400.

[0038] Preferably, the amount of activated carbon is 0.1-10wt% of the sebacic acid content in the mixed solution, and further is 1-5wt%; for example, the amount of activated carbon can be 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%.

[0039] In some embodiments, the temperature of the decolorization treatment is 50 to 100°C, further 60 to 80°C.

[0040] In some embodiments, the decolorization treatment time is 10 to 180 min, further 15 to 120 min.

[0041] In some embodiments, after decolorization, the activated carbon is preferably separated by plate and frame filtration, centrifugal filtration, or vacuum negative pressure filtration.

[0042] In some embodiments, in step (2), the decolorizing solution is crystallized by cooling, and the cooling crystallization comprises: first cooling the decolorizing solution to 40-50°C (crystallization point) at a rate of 2-15°C / h, keeping the temperature for 10-90 minutes, and then cooling the temperature to 15-30°C at a rate of 2-15°C / h, and keeping the temperature for 30-120 minutes.

[0043] In some embodiments, the method further comprises: adding activated carbon to the filtrate obtained in step (1) for decolorization or using a macroporous adsorption resin for decolorization to obtain a decolorized solution, and then acidifying and crystallizing the decolorized solution.

[0044] In the present invention, when activated carbon is used for decolorization, the amount of activated carbon added is controlled to be 0.1-10wt% of the content of sebacic acid in the filtrate, the decolorization temperature is 50-100°C, and the decolorization time is 10-180min.

[0045] In some embodiments, the macroporous adsorption resin is preferably D101 and / or D102 resin. Specifically, the filtrate obtained in step (1) is added to a macroporous adsorption resin chromatography column for decolorization, and the flow acceleration is preferably controlled to be 0.5-2BV.

[0046] In some embodiments, the method further comprises: washing the solid obtained after solid-liquid separation in step (2) with an alcohol organic solvent and then drying it.

[0047] In some embodiments, the method further comprises: placing the solid obtained by solid-liquid separation in step (2) in water at 60 to 110° C., or further at 95 to 110° C., keeping the temperature for 15 to 150 minutes, then cooling the temperature to 20 to 45° C., performing solid-liquid separation, and drying the obtained solid to obtain a sebacic acid product.

[0048] Preferably, after cooling to 20-45° C., the sebacic acid is separated and washed by centrifugal filtration, plate and frame filtration, drum filtration or the like.

[0049] In some embodiments, the washed sebacic acid is dried, and the drying method includes but is not limited to any one or a combination of paddle drying, airflow drying or belt drying, to finally obtain a sebacic acid product with high purity, low impurity content and good color.

[0050] The present invention also provides a sebacic acid product obtained by the above extraction and purification method.

[0051] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0052] Compared with the prior art, the technical effects of the present invention are at least:

[0053] The extraction and purification method provided by the present invention can remove a large amount of pigments and impurities to obtain a decolorized liquid with a turbidity of less than 5 NTU, thereby improving the quality, purity and chromaticity of the sebacic acid product. The extraction and purification method is simple and easy to operate, and is conducive to large-scale industrial production. DETAILED DESCRIPTION

[0054] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the embodiments. The experimental methods in the following examples that do not specify specific conditions are selected according to conventional methods and conditions, or according to the product specifications. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0055] In the present invention, unless otherwise specified, all raw materials used can be obtained from commercial sources. Details of the related tests involved are as follows.

[0056] The test method in the embodiment is as follows:

[0057] 1. Sebacic acid content (purity): Take the sample to be tested and perform conventional gas chromatography pretreatment, gas chromatography detection, and calculate the sebacic acid content based on the sebacic acid peak area.

[0058] 2. Moisture content: Loss on drying method, when the sample is heated to constant weight at 105℃, the proportion of volatile matter lost in the sample is the percentage of the sample.

[0059] 3. Ash content: Take the sample to be tested and burn it in a crucible, then burn it in a muffle furnace at 700-800℃ for 2h. Measure the weight after cooling to constant weight and calculate the percentage of the sample weight.

[0060] 4. Determination of nitrogen content: measured by Kjeldahl method.

[0061] 5. Determination of iron ion content: The iron salt content (ppm) in terms of Fe in the sample was determined using the o-phenanthroline method.

[0062] 6. Turbidity (unit: NTU) test method: Use the nephelometric method, and refer to US EPA180.1.

[0063] 7. Chroma (Hazen) test method: After dissolving 10% potassium hydroxide, measure the value with a 5 cm cuvette.

[0064] Preparation Example 1 Fermentation to produce sebacic acid (the pH of the fermentation liquid is terminated to be less than 7)

[0065] A glycerol tube of Candida tropicalis CAT H1614 was inoculated into a seed bottle containing 30 ml of YPD liquid medium (2% glucose, 1% yeast extract, 2% peptone), with a natural pH, and cultured at 29° C. with a shaking incubator at 220 rpm for 1 day.

[0066] Take shake flask seeds and access to a seed tank containing 5L seed culture medium (sucrose 2%, corn steep liquor 0.3%, yeast extract 0.5%, KH2PO40.8%, urea 0.3%), inoculum size is 10%, and the initial pH value of the inoculated system is 6.0, at 29°C, ventilation rate 0.4vvm, tank pressure 0.08MPa, cultivate 18h, pH naturally drops to 3 during the cultivation process, and OD620 is inoculated into a fermentation tank containing 6L fermentation medium (glucose 4%, corn steep liquor 0.5%, yeast extract 0.4%, potassium nitrate 1%, potassium dihydrogen phosphate 0.1%, urea 0.12%, ammonium sulfate 0.06% and sodium chloride 0.1%) when it grows to 0.7, the initial volume after inoculation is 5L, inoculum size 20%, the fermentation process control temperature is 30°C, ventilation rate is about 0.4vvm, tank pressure (gauge pressure) is about 0.12MPa, and the control dissolved oxygen is not less than 20%. 30% of liquid alkali is added to control the pH value of the fermentation liquid. In the early stage of fermentation, the main feature is bacterial growth. The initial pH of fermentation is about 6.5. With the growth of microorganisms, the pH of the fermentation liquid gradually decreases. The pH is controlled to be no less than 3.0. When the optical density of the bacteria (OD620) is greater than 0.5 (diluted 30 times), the pH is controlled to be 5 until the end of fermentation. Decane is added in batches when the fermentation cycle is 10 to 20 hours to control the decane content in the fermentation liquid to not exceed 10%.

[0067] Preparation Example 2 Fermentation to produce sebacic acid (the pH of the fermentation liquid is terminated to be greater than 7)

[0068] Referring to the fermentation method of Example 4 in the Chinese patent application number CN200410018255.7 and publication number CN1570124A, sebacic acid is produced by fermentation using decane as a substrate.

[0069] Example 1

[0070] (1) adding alkali to the sebacic acid fermentation broth (pH value of 5.1) obtained in Preparation Example 1 to adjust the pH value to 8.2, heating to 90° C. and filtering with a ceramic membrane to remove the bacteria, the operating pressure being 0.3 MPa, the pore size of the ceramic membrane being 0.05 μm, and obtaining a filtrate;

[0071] The filtrate was added to a macroporous adsorption resin D101 chromatography column for decolorization, and the flow acceleration was controlled to be 1.5 BV. After decolorization, the activated carbon was separated by plate and frame filtration to obtain a decolorized liquid;

[0072] The pH value of the decolorizing solution was adjusted to 3 with sulfuric acid, the temperature was raised to 98°C, kept for 60 minutes, then cooled to 30°C, separated by plate and frame filtration, and dried to obtain crude sebacic acid;

[0073] (2) mixing and dissolving crude sebacic acid and methanol (purity ≥ 97%) at a temperature of 60° C. to obtain a mixed solution, wherein the mass ratio of crude sebacic acid to methanol (purity ≥ 97%) is controlled to be 1:2;

[0074] The mixed solution was decolorized using activated carbon (iodine value of 450), the amount of activated carbon added was 8wt% of the content of sebacic acid in the mixed solution, the decolorization temperature was 80°C, the decolorization time was 90min, and then the activated carbon was separated by plate and frame filtration to obtain a decolorized solution with a turbidity of <5NTU;

[0075] The decolorizing solution was cooled to 49°C at a rate of 5°C / h and kept warm for 30 minutes, then cooled to 20°C at a rate of 5°C / h and kept warm for 1 hour. The sebacic acid solid was obtained after plate and frame filtration, which was washed with methanol and dried to obtain the DC10 product.

[0076] Example 2

[0077] The method is basically the same as Example 1, except that in step (2), activated carbon (iodine value is 1000) is used to decolorize the mixed solution, and the amount of activated carbon added is 3.5wt% of the content of sebacic acid in the mixed solution.

[0078] Example 3

[0079] The method is basically the same as Example 1, except that in step (2), the mass ratio of crude sebacic acid to methanol (purity ≥ 97%) is controlled to be 1:5, and the amount of activated carbon added is 4wt% of the sebacic acid content in the mixed solution.

[0080] Example 4

[0081] (1) adding alkali to the sebacic acid fermentation broth (pH value is 8.0) obtained in Preparation Example 2 to adjust the pH value to 8.5, heating to 85° C. and filtering with a ceramic membrane to remove the bacteria, the operating pressure is 0.3 MPa, the pore size of the ceramic membrane is 0.05 μm, and a filtrate is obtained;

[0082] Adding activated carbon to the filtrate for decolorization, the amount of activated carbon used is 5wt% of the content of sebacic acid in the filtrate, the decolorization temperature is 80°C, the decolorization time is 60min, and after decolorization, the activated carbon is separated by plate and frame filtration to obtain a decolorized liquid;

[0083] The pH value of the decolorizing solution was adjusted to 3 with sulfuric acid, the temperature was raised to 98°C, kept for 60 minutes, then cooled to 30°C, separated by plate and frame filtration, and dried to obtain crude sebacic acid;

[0084] (2) mixing and dissolving the crude sebacic acid and methanol (purity ≥ 97%) at 60° C. to obtain a mixed solution, wherein the mass ratio of the crude sebacic acid to the methanol is controlled to be 1:3.5;

[0085] The mixed solution was decolorized using activated carbon (iodine value of 580), the amount of activated carbon added was 6wt% of the content of sebacic acid in the mixed solution, the decolorization temperature was 60°C, the decolorization time was 90min, and then the activated carbon was separated by plate and frame filtration to obtain a decolorized solution with a turbidity of less than 5NTU;

[0086] The decolorizing solution was cooled to 44°C at a rate of 5°C / h and kept warm for 30 minutes, then cooled to 20°C at a rate of 5°C / h and kept warm for 1 hour. The sebacic acid solid was obtained after plate and frame filtration, which was washed with methanol and dried to obtain the DC10 product.

[0087] Example 5

[0088] It is basically the same as Example 4, except that: in step (2), the cooling crystallization step: the decolorizing solution is directly cooled to 20°C at a rate of 5°C / h.

[0089] Example 6

[0090] It is basically the same as Example 4, except that in step (2), the amount of activated carbon added is 0.5wt% of the content of sebacic acid in the mixed solution, and methanol washing is not required.

[0091] Example 7

[0092] The method is basically the same as Example 4, except that the solid sebacic acid obtained after plate and frame filtration in step (2) is placed in water at 108°C, kept warm for 100 minutes, then cooled to 25°C, separated by centrifugal filtration, and the obtained solid is dried to obtain a sebacic acid product.

[0093] Comparative Example 1

[0094] The method is basically the same as Example 1, except that the pH value of the sebacic acid fermentation broth (pH value is 5.1) obtained in Preparation Example 1 is adjusted to 5.5, and a decolorized liquid with a turbidity of >7 NTU is obtained after decolorization with methanol solvent.

[0095] Comparative Example 2

[0096] The method is basically the same as Example 1, except that after the mixed solution is decolorized using activated carbon (iodine value is 350), a decolorized solution with a turbidity of >10 NTU is obtained.

[0097] The performance of the DC10 products obtained in Examples 1-7 and Comparative Examples 1-2 was tested, and the results are shown in Table 1.

[0098] Table 1

[0099]

[0100] The embodiments described in the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Those skilled in the art may make various other substitutions, changes and improvements within the scope of the present invention. Therefore, the present invention is not limited to the above embodiments, but is only limited by the claims.

Claims

1. A method for extracting and refining sebacic acid, characterized in that: The method comprises: (1) filtering the sebacic acid fermentation broth or the treated broth thereof, acidifying and crystallizing the filtrate, performing solid-liquid separation, and drying to obtain a crude sebacic acid product; (2) The crude sebacic acid product is mixed and dissolved with an alcohol organic solvent at a temperature of 50 to 97° C., and then decolorized to obtain a decolorized solution with a turbidity of less than 5 NTU. The decolorized solution is crystallized and solid-liquid separated to obtain a sebacic acid product.

2. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: Before performing step (1), the pH value of the sebacic acid fermentation broth is 2-12, further 4-12, further 4-9, further 4-6.5 or 7.3-8.5, further 5-6.5 or 7.5-8.

3.

3. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: The filtration in step (1) is membrane filtration, and the membrane filtration temperature is controlled to be 45-95° C.; and / or, In step (1), before filtering, the pH value of the sebacic acid fermentation liquid or its treated liquid is adjusted to above 7, and further to above 8.

4. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: The acidification crystallization in step (1) comprises: adjusting the pH value of the filtrate to 2-4, heating the filtrate to 80-110° C., further keeping the filtrate at 90-98° C. for ≥30 min, and then cooling the filtrate to 30-40° C.

5. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: In step (2), the crude sebacic acid is mixed and dissolved with an alcohol organic solvent at a temperature of 50 to 75° C., and further at a temperature of 60 to 70° C.; and / or, The mass ratio of the crude sebacic acid to the alcohol organic solvent is 1:(2-6), further 1:(3-5); and / or, The alcohol organic solvent includes a monohydric alcohol or a dihydric alcohol having 1 to 4 carbon atoms, and further includes at least one of methanol, ethanol, n-butanol, and isopropanol.

6. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: In step (2), activated carbon is used for the decolorization treatment. Preferably, the iodine value of the activated carbon is greater than 400, further greater than 550, and further greater than 600 to 1400; Preferably, the amount of activated carbon is 0.1 to 10 wt % of the sebacic acid content in the mixed solution, further 1 to 5 wt %; and / or The temperature of the decolorization treatment is 50 to 100° C., and further 60 to 80° C.; and / or, The decolorization time is 10 to 180 minutes, further 15 to 120 minutes; and / or, After decolorization, the activated carbon is separated by plate and frame filtration, centrifugal filtration, and vacuum negative pressure filtration.

7. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: In step (2), the decolorizing solution is crystallized by cooling, and the crystallization by cooling comprises: first cooling the decolorizing solution to 40-50°C (crystallization point) at a rate of 2-15°C / h, keeping the temperature for 10-90min, and then cooling the temperature to 15-30°C at a rate of 2-15°C / h, and keeping the temperature for 30-120min.

8. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: The method further comprises: adding activated carbon to the filtrate obtained in step (1) for decolorization or using a macroporous adsorption resin for decolorization to obtain a decolorized solution, and then acidifying and crystallizing the decolorized solution; and / or, The method further comprises: in step (2), the solid obtained after solid-liquid separation is washed with an alcohol organic solvent and then dried.

9. The method for extracting and purifying sebacic acid according to claim 1, characterized in that: include: The solid obtained by solid-liquid separation in step (2) is placed in water at 60-110° C., further at 95-110° C., and kept warm for 15-150 minutes, then cooled to 20-45° C., and then subjected to solid-liquid separation treatment, and the obtained solid is dried to obtain a sebacic acid product.

10. A sebacic acid product obtained by the extraction and purification method according to any one of claims 1 to 9.

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