CN111848387A - Method for separating and purifying succinic acid from mixed dibasic acid residues - Google Patents
Method for separating and purifying succinic acid from mixed dibasic acid residues Download PDFInfo
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- CN111848387A CN111848387A CN202010773982.3A CN202010773982A CN111848387A CN 111848387 A CN111848387 A CN 111848387A CN 202010773982 A CN202010773982 A CN 202010773982A CN 111848387 A CN111848387 A CN 111848387A
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- C07—ORGANIC CHEMISTRY
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- C07C51/42—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/47—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/50—Use of additives, e.g. for stabilisation
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Abstract
The invention relates to the technical field of chemical byproduct treatment, in particular to a method for separating and purifying succinic acid from mixed dibasic acid residues. The invention disperses the mixed dibasic acid residue in the halohydrocarbon to prepare the mixed solution, adds glutaric acid, heats to a specific temperature, keeps the temperature and stirs, then carries out solid-liquid separation, and the obtained solid is the crude product of succinic acid. The method is simple to operate, the technological parameters are easy to control, the succinic acid can be separated from the mixed dibasic acid residues, the recovery rate and the purity of the obtained succinic acid crude product are high, and the method has important significance for improving the added value of chemical byproducts, reducing the production of finished products and enriching the product structure.
Description
Technical Field
The invention belongs to the technical field of chemical byproduct treatment, and particularly relates to a method for separating and purifying succinic acid from mixed dibasic acid residues.
Background
The mixed dibasic acid (DBA) is a byproduct in the production process of adipic acid, and comprises Succinic Acid (SA), Glutaric Acid (GA) and adipic acid (ADA) as main components, wherein glutaric acid accounts for about 65 wt%, succinic acid accounts for about 25 wt%, and adipic acid accounts for about 10 wt%. In actual production, 50-60kg DBA is generally produced per 1t of adipic acid product produced. The price of DBA is only 3000 yuan/ton, which is far lower than the market price of each dibasic acid, and the application is limited, and the DBA can be applied only by further processing.
In the prior art, methods for extracting and separating glutaric acid from DBA are available, and the DBA residue obtained after extracting and separating glutaric acid mainly contains succinic acid, adipic acid and residual glutaric acid. The market price of the succinic acid is about 1.6 ten thousand yuan/t, and the succinic acid can be used for manufacturing coatings, dyes, adhesives, medicaments and the like and has extremely high market value. Therefore, the separation of high-purity succinic acid from DBA residues has very important practical significance for reducing the production cost, improving the added value of byproducts, enriching the product structure of adipic acid production enterprises and the like. It is difficult to separate succinic acid from DBA residue because succinic acid has a similar dissolution behavior to adipic acid in most solvents. At present, no method for purifying and separating succinic acid from DBA residues is reported.
Disclosure of Invention
Aiming at the problem that succinic acid is difficult to separate from DBA residues, the invention provides a method for separating and purifying succinic acid from mixed dibasic acid residues.
In order to achieve the purpose of the invention, the embodiment of the invention adopts the following technical scheme:
a method for separating and purifying succinic acid from mixed dibasic acid residues, wherein the mixed dibasic acid residues comprise succinic acid, glutaric acid and adipic acid, and the method comprises the following steps: dispersing the mixed dibasic acid residue in halogenated hydrocarbon to prepare a mixed solution, adding glutaric acid, heating to 75-85 ℃, keeping the temperature, stirring for 10-30 min, and carrying out solid-liquid separation to obtain a solid, namely a succinic acid crude product.
Experiments show that the difference between the dissolution behavior of the mixed dibasic acid in the halogenated hydrocarbon and the dissolution behavior of the single dibasic acid in the halogenated hydrocarbon is large, and the solubility of the adipic acid is obviously improved when a certain amount of glutaric acid is added into the halogenated hydrocarbon containing the mixed dibasic acid residue within a specific temperature range. Therefore, halogenated hydrocarbon is used as a solvent to disperse the mixed dibasic acid residues, glutaric acid is added, the glutaric acid is dissolved in the mixed solution, the solubility of the adipic acid in the halogenated hydrocarbon is obviously improved at 75-85 ℃, so that the adipic acid is dissolved in the halogenated hydrocarbon, and then the succinic acid crude product can be separated from the mixed dibasic acid residues through solid-liquid separation. The method is simple to operate, the technological parameters are easy to control, and the recovery rate and purity of the obtained succinic acid crude product are high.
Preferably, the succinic acid content in the mixed dibasic acid residue is more than 50 wt%.
Preferably, the mass of glutaric acid in the mixed solution after addition of glutaric acid is 29-50% of the mass of the mixed dibasic acid residue. The dosage range can obviously improve the solubility of the adipic acid, so that more adipic acid is dissolved in the halogenated hydrocarbon, and the succinic acid with higher purity is obtained.
Preferably, the halogenated hydrocarbon is selected from 1, 2-dibromoethane, 1, 2-tribromoethane, dichloropropane, 1,2, 3-trichloropropane, 1,2, 3-tribromopropane, 1, 4-dichlorobutane, 1, 5-dibromopentane or 1-bromo-5-chloropentane.
Preferably, the mass of the halogenated hydrocarbon is 10 to 16 times of the mass of the mixed dibasic acid residue. Within the range of the solid-to-liquid ratio, the purity of the obtained succinic acid is higher.
Preferably, the mass of the halogenated hydrocarbon is 11 times of the mass of the mixed dibasic acid residue.
Preferably, the method further comprises refining the obtained crude succinic acid.
Preferably, the refining method is as follows: dissolving the succinic acid crude product in a solvent, heating to 75-85 ℃, cooling to 25-35 ℃ at a cooling rate of 0.7-1 ℃, preserving heat and filtering; the solvent comprises n-butanol, isobutanol, n-pentanol, cyclohexanol or cyclohexanone. The refining conditions are favorable for further improving the purity of the succinic acid product.
Preferably, the solvent is cyclohexanol. The highest product purity can be obtained by taking cyclohexanol as a solvent, and the residual quantity of glutaric acid and adipic acid in the obtained product is minimum.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
The embodiment provides a method for separating and purifying succinic acid from mixed dibasic acid residues, wherein the mixed dibasic acid residues are residues obtained after glutaric acid is extracted and separated from the mixed dibasic acid, and the residues contain 55.2 wt% of succinic acid, 22.8 wt% of glutaric acid and 22.0 wt% of adipic acid.
Dissolving 500g of the residue in 5500g of 1, 2-dibromoethane to prepare a mixed solution, adding 175.5g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 35.1 percent of that of the mixed dibasic acid residue, heating to 80 ℃, keeping the temperature at 75-85 ℃, stirring for 20min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is determined to be 98.25 percent, and the purity is determined to be 96.72 percent.
Refining the obtained succinic acid crude product: and dissolving the obtained succinic acid crude product in cyclohexanol, heating to 80 ℃, cooling to 30 ℃ at a cooling rate of 0.85 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 82.34 percent and the purity is 99.71 percent.
Example 2
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 53.4 wt% of succinic acid, 23.6 wt% of glutaric acid, and 23.0 wt% of adipic acid.
Dissolving 500g of the residue in 6000g of 1,1, 2-tribromoethane to prepare a mixed solution, adding 183.5g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 36.7% of that of the mixed dibasic acid residue, heating to 80 ℃, keeping the temperature at 75-85 ℃, stirring for 20min, and filtering to obtain a solid, namely a crude succinic acid product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is determined to be 98.01 percent, and the purity is determined to be 96.45 percent.
Refining the obtained succinic acid crude product: and dissolving the obtained succinic acid crude product in cyclohexanol, heating to 80 ℃, cooling to 35 ℃ at the cooling rate of 0.85 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 82.79 percent and the purity is 99.53 percent.
Example 3
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 57.5 wt% of succinic acid, 18.3 wt% of glutaric acid, and 24.2 wt% of adipic acid.
Dissolving 500g of the residue in 5000g of dichloropropane to prepare a mixed solution, adding 147.25g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 29.45 percent of that of the mixed dibasic acid residue, heating to 75 ℃, keeping the temperature at 75-85 ℃, stirring for 30min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 97.95 percent and the purity is 96.27 percent.
Refining the obtained succinic acid crude product: dissolving the obtained succinic acid crude product in n-butanol, heating to 75 deg.C, cooling to 28 deg.C at a cooling rate of 0.70 deg.C/min, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 83.16 percent and the purity is 99.31 percent.
Example 4
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 59.8 wt% of succinic acid, 17.2 wt% of glutaric acid, and 23.0 wt% of adipic acid.
Dissolving 500g of the residue in 6500g of 1,2, 3-trichloropropane to prepare a mixed solution, adding 190.75g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 38.15 percent of that of the mixed dibasic acid residue, heating to 77 ℃, keeping the temperature at 75-85 ℃, stirring for 25min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 97.84 percent and the purity is 96.23 percent.
Refining the obtained succinic acid crude product: dissolving the obtained succinic acid crude product in isobutanol, heating to 77 ℃, then cooling to 32 ℃ at the cooling rate of 0.75 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 82.65 percent and the purity is 99.10 percent.
Example 5
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 56.4 wt% of succinic acid, 21.5 wt% of glutaric acid, and 22.1 wt% of adipic acid.
Dissolving 500g of the residue in 7000g of 1,2, 3-tribromopropane to prepare a mixed solution, adding 166.55g of glutaric acid to enable the mass of the glutaric acid in the mixed solution to be 33.31% of the mass of the mixed dibasic acid residue, heating to 79 ℃, keeping the temperature at 75-85 ℃, stirring for 20min, and filtering to obtain a solid, namely a crude succinic acid product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 97.72 percent and the purity is 96.13 percent.
Refining the obtained succinic acid crude product: dissolving the obtained succinic acid crude product in n-amyl alcohol, heating to 79 ℃, cooling to 35 ℃ at the cooling rate of 0.80 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 83.22 percent and the purity is 99.36 percent.
Example 6
The embodiment provides a method for separating and purifying succinic acid from mixed dibasic acid residues, wherein the mixed dibasic acid residues are residues obtained after glutaric acid is extracted and separated from the mixed dibasic acid, and the residues contain 55.7 wt% of succinic acid, 21.6 wt% of glutaric acid and 22.7 wt% of adipic acid.
Dissolving 500g of the residue in 7500g of 1, 4-dichlorobutane to prepare a mixed solution, adding 208.2g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 41.46 percent of that of the mixed dibasic acid residue, heating to 81 ℃, keeping the temperature at 75-85 ℃, stirring for 20min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 97.58 percent and the purity is 95.95 percent.
Refining the obtained succinic acid crude product: dissolving the obtained succinic acid crude product in cyclohexanone, heating to 81 ℃, cooling to 25 ℃ at a cooling rate of 0.90 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 82.41 percent and the purity is 99.17 percent.
Example 7
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 57.2 wt% of succinic acid, 21.3 wt% of glutaric acid, and 21.5 wt% of adipic acid.
Dissolving 500g of the residue in 8000g of 1, 5-dibromopentane to prepare a mixed solution, adding 216.9g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 43.38 percent of that of the mixed dibasic acid residue, heating to 83 ℃, keeping the temperature at 75-85 ℃, stirring for 15min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 97.49 percent and the purity is 95.81 percent.
Refining the obtained succinic acid crude product: and dissolving the obtained succinic acid crude product in cyclohexanol, heating to 83 ℃, cooling to 28 ℃ at the cooling rate of 0.95 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 82.19 percent and the purity is 99.59 percent.
Example 8
This example provides a method for separating and purifying succinic acid from mixed dibasic acid residue, wherein the mixed dibasic acid residue is obtained from residue obtained after extracting and separating glutaric acid from mixed dibasic acid, and contains 54.3 wt% of succinic acid, 22.5 wt% of glutaric acid, and 23.2 wt% of adipic acid.
Dissolving 500g of the residue in 5500g of 1-bromo-5-chloropentane to prepare a mixed solution, adding 249.75g of glutaric acid to ensure that the mass of the glutaric acid in the mixed solution is 49.95 percent of that of the mixed dibasic acid residue, heating to 85 ℃, keeping the temperature at 75-85 ℃, stirring for 10min, and filtering to obtain a solid, namely a succinic acid crude product. Quantitative analysis is carried out on the succinic acid crude product by using Agilent GC-7980 gas chromatography, and the yield of the succinic acid is determined to be 98.19 percent, and the purity is determined to be 96.22 percent.
Refining the obtained succinic acid crude product: and dissolving the obtained succinic acid crude product in cyclohexanol, heating to 85 ℃, then cooling to 27 ℃ at the cooling rate of 1.00 ℃/min, preserving heat, filtering, and drying to obtain refined succinic acid. Quantitative analysis is carried out on the refined succinic acid by an Agilent GC-7980 gas chromatography, and the yield of the succinic acid is 81.83 percent and the purity is 99.70 percent.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (9)
1. A method for separating and purifying succinic acid from mixed dibasic acid residues, wherein the mixed dibasic acid residues comprise succinic acid, glutaric acid and adipic acid, and the method is characterized by comprising the following steps: dispersing the mixed dibasic acid residue in halogenated hydrocarbon to prepare a mixed solution, adding glutaric acid, heating to 75-85 ℃, keeping the temperature, stirring for 10-30 min, and carrying out solid-liquid separation to obtain a solid, namely a succinic acid crude product.
2. The method for separating and purifying succinic acid from the mixed dibasic acid residue as claimed in claim 1, wherein the content of succinic acid in the mixed dibasic acid residue is more than 50 wt%.
3. The method for separating and purifying succinic acid from the mixed dibasic acid residue according to claim 1, wherein the mass of glutaric acid in the mixed solution after the addition of glutaric acid is 29 to 50% of the mass of the mixed dibasic acid residue.
4. The method for separating and purifying succinic acid from mixed dibasic acid residue according to claim 1, wherein the halogenated hydrocarbon is selected from the group consisting of 1, 2-dibromoethane, 1, 2-tribromoethane, dichloropropane, 1,2, 3-trichloropropane, 1,2, 3-tribromopropane, 1, 4-dichlorobutane, 1, 5-dibromopentane and 1-bromo-5-chloropentane.
5. The method for separating and purifying succinic acid from the mixed dibasic acid residue according to claim 4, wherein the mass of the halogenated hydrocarbon is 10 to 16 times of the mass of the mixed dibasic acid residue.
6. The method for separating and purifying succinic acid from the mixed dibasic acid residue as claimed in claim 5, wherein the mass of the halogenated hydrocarbon is 11 times that of the mixed dibasic acid residue.
7. The method for separating and purifying succinic acid from the mixed dibasic acid residue according to any one of claims 1 to 6, wherein the method further comprises refining the crude succinic acid.
8. The method for separating and purifying succinic acid from the mixed dibasic acid residue according to claim 7, wherein the refining method comprises the following steps: dissolving the succinic acid crude product in a solvent, heating to 75-85 ℃, cooling to 25-35 ℃ at a cooling rate of 0.7-1 ℃, preserving heat and filtering; the solvent comprises n-butanol, isobutanol, n-pentanol, cyclohexanol or cyclohexanone.
9. The method of claim 8, wherein the solvent is cyclohexanol.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4146730A (en) * | 1975-12-25 | 1979-03-27 | Asahi Kasei Kogyo Kabushiki Kaisha | Method for obtaining glutaric acid, succinic acid, and adipic acid from an acid mixture comprising them |
| CN106957223A (en) * | 2017-04-24 | 2017-07-18 | 上海华峰新材料研发科技有限公司 | A kind of method that C4 ~ C6 dicarboxylic acid monomers are purified from adipic acid by-product mixed dibasic acid |
| CN107522614A (en) * | 2017-07-24 | 2017-12-29 | 唐山开滦化工科技有限公司 | A kind of low-carbon halogenated alkane is used for the method for glutaric acid in Separation ＆ Purification mixed dibasic acid |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4146730A (en) * | 1975-12-25 | 1979-03-27 | Asahi Kasei Kogyo Kabushiki Kaisha | Method for obtaining glutaric acid, succinic acid, and adipic acid from an acid mixture comprising them |
| CN106957223A (en) * | 2017-04-24 | 2017-07-18 | 上海华峰新材料研发科技有限公司 | A kind of method that C4 ~ C6 dicarboxylic acid monomers are purified from adipic acid by-product mixed dibasic acid |
| CN107522614A (en) * | 2017-07-24 | 2017-12-29 | 唐山开滦化工科技有限公司 | A kind of low-carbon halogenated alkane is used for the method for glutaric acid in Separation ＆ Purification mixed dibasic acid |
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