CN114014835A - Glycolide purification process - Google Patents
Glycolide purification process Download PDFInfo
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- CN114014835A CN114014835A CN202111502229.1A CN202111502229A CN114014835A CN 114014835 A CN114014835 A CN 114014835A CN 202111502229 A CN202111502229 A CN 202111502229A CN 114014835 A CN114014835 A CN 114014835A
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- glycolide
- liquid
- glycolic acid
- dissolving
- impurities
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- RKDVKSZUMVYZHH-UHFFFAOYSA-N 1,4-dioxane-2,5-dione Chemical compound O=C1COC(=O)CO1 RKDVKSZUMVYZHH-UHFFFAOYSA-N 0.000 title claims abstract description 67
- 238000000746 purification Methods 0.000 title claims abstract description 19
- 239000012535 impurity Substances 0.000 claims abstract description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000012074 organic phase Substances 0.000 claims abstract description 24
- 239000012071 phase Substances 0.000 claims abstract description 21
- 238000000622 liquid--liquid extraction Methods 0.000 claims abstract description 18
- 238000000638 solvent extraction Methods 0.000 claims abstract description 18
- 238000004821 distillation Methods 0.000 claims abstract description 16
- 239000012043 crude product Substances 0.000 claims abstract description 15
- 239000004744 fabric Substances 0.000 claims abstract description 14
- 238000004090 dissolution Methods 0.000 claims abstract description 13
- 238000005191 phase separation Methods 0.000 claims abstract description 13
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 12
- 239000002808 molecular sieve Substances 0.000 claims abstract description 10
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000010521 absorption reaction Methods 0.000 claims abstract description 9
- 229910017053 inorganic salt Inorganic materials 0.000 claims abstract description 8
- 238000001035 drying Methods 0.000 claims abstract description 7
- 239000003960 organic solvent Substances 0.000 claims abstract description 7
- 239000000243 solution Substances 0.000 claims description 22
- 238000000034 method Methods 0.000 claims description 15
- 239000000706 filtrate Substances 0.000 claims description 10
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 9
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 9
- 238000002425 crystallisation Methods 0.000 claims description 9
- 238000003756 stirring Methods 0.000 claims description 8
- 230000008025 crystallization Effects 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 6
- 238000000605 extraction Methods 0.000 claims description 5
- 239000011259 mixed solution Substances 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 238000000926 separation method Methods 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 claims description 3
- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid Chemical compound CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 claims description 3
- 239000012452 mother liquor Substances 0.000 claims description 2
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 abstract description 64
- 239000000047 product Substances 0.000 abstract description 11
- 239000013638 trimer Substances 0.000 abstract description 11
- 239000002253 acid Substances 0.000 abstract description 9
- 239000006227 byproduct Substances 0.000 abstract description 7
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 abstract description 6
- 238000005119 centrifugation Methods 0.000 abstract description 5
- 230000018044 dehydration Effects 0.000 abstract description 4
- 238000006297 dehydration reaction Methods 0.000 abstract description 4
- CFQZKFWQLAHGSL-FNTYJUCDSA-N (3e,5e,7e,9e,11e,13e,15e,17e)-18-[(3e,5e,7e,9e,11e,13e,15e,17e)-18-[(3e,5e,7e,9e,11e,13e,15e)-octadeca-3,5,7,9,11,13,15,17-octaenoyl]oxyoctadeca-3,5,7,9,11,13,15,17-octaenoyl]oxyoctadeca-3,5,7,9,11,13,15,17-octaenoic acid Chemical compound OC(=O)C\C=C\C=C\C=C\C=C\C=C\C=C\C=C\C=C\OC(=O)C\C=C\C=C\C=C\C=C\C=C\C=C\C=C\C=C\OC(=O)C\C=C\C=C\C=C\C=C\C=C\C=C\C=C\C=C CFQZKFWQLAHGSL-FNTYJUCDSA-N 0.000 abstract description 3
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 abstract description 2
- 230000000694 effects Effects 0.000 abstract description 2
- 238000001914 filtration Methods 0.000 abstract description 2
- 229910021642 ultra pure water Inorganic materials 0.000 description 9
- 239000012498 ultrapure water Substances 0.000 description 9
- 229920000954 Polyglycolide Polymers 0.000 description 4
- 238000005292 vacuum distillation Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 3
- 239000012265 solid product Substances 0.000 description 3
- 238000001291 vacuum drying Methods 0.000 description 3
- 239000000155 melt Substances 0.000 description 2
- 239000004633 polyglycolic acid Substances 0.000 description 2
- 238000001953 recrystallisation Methods 0.000 description 2
- 229910052938 sodium sulfate Inorganic materials 0.000 description 2
- 235000011152 sodium sulphate Nutrition 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 239000000539 dimer Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007794 irritation Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 229920002643 polyglutamic acid Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004227 thermal cracking Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D319/00—Heterocyclic compounds containing six-membered rings having two oxygen atoms as the only ring hetero atoms
- C07D319/10—1,4-Dioxanes; Hydrogenated 1,4-dioxanes
- C07D319/12—1,4-Dioxanes; Hydrogenated 1,4-dioxanes not condensed with other rings
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a purification process of glycolide, which comprises the steps of dissolving crude glycolide in an organic solvent through crude product dissolution; then, transferring glycolic acid, a small amount of glycolic acid dimer and glycolic acid trimer and a small amount of glycolic acid tetramer impurities in the by-products into an extracting agent phase by liquid-liquid extraction; then, through two-phase separation, impurities dissolved in the extracting agent can be removed along with the separated extracting agent phase; adding inorganic salt (anhydrous magnesium sulfate or anhydrous sodium sulfate) or molecular sieve into the separated organic phase to adsorb water, and filtering with small filter diameter filter cloth to remove the inorganic salt and molecular sieve after water absorption and impurities such as glycolic acid dimer, glycolic acid trimer and glycolic acid tetramer which are not dissolved in the extractant, thereby realizing dehydration and impurity removal effects, further improving the purity of glycolide products and reducing the acid value of the glycolide products; finally, the high-purity glycolide product with greatly improved purity can be obtained by distillation, concentration, centrifugation and drying.
Description
The technical field is as follows:
the invention relates to the field of chemical industry, in particular to a glycolide purification process.
Background art:
polyglycolide (PGA), also known as polyglycolic acid, is a highly crystalline, biodegradable aliphatic polymer, has the characteristics of no toxicity, no irritation, biodegradability, absorbability, high strength, good plasticity, easy processing and forming and the like, and is mainly used in the fields of surgical sutures and the like. Glycolide is used as a raw material for preparing polyglycolide, and the purity of the glycolide can directly influence the product quality of the polyglycolide.
Glycolide is generally obtained by thermal cracking of low-molecular-weight polyglycolic acid, but glycolic acid, dimer, trimer, tetramer, moisture and other by-products are also produced during the cracking process. In order to remove the byproducts and improve the purity of the glycolide, the conventional purification methods comprise a recrystallization method, a rectification method and a melt crystallization method, and the recrystallization method is difficult to realize continuous operation; the rectification method can cause polymerization reaction of glycolide in the purification process, and the purification yield is low; the melt crystallization method has long treatment period and high energy consumption, and is not suitable for industrial application.
The invention content is as follows:
the invention aims to provide a glycolide purification process capable of effectively improving the purity and acid value of a glycolide product.
The invention is implemented by the following technical scheme:
a process for the purification of glycolide, comprising the steps of:
(1) dissolving a crude product: dissolving crude glycolide in an organic solvent to obtain a dissolved solution;
(2) liquid-liquid extraction: adding an extracting agent into a dissolving solution obtained in the step (1) crude product dissolving, and fully stirring to obtain a mixed solution;
(3) two-phase separation: separating the mixed liquid obtained in the liquid-liquid extraction in the step (2) by an extraction centrifuge to obtain an extractant phase and an organic phase;
(4) dewatering and impurity removal: dehydrating the organic phase obtained in the step (3) two-phase separation, and removing insoluble solid particles contained in the organic phase to obtain glycolide filtrate;
(5) distillation and crystallization: and (4) distilling and concentrating the glycolide filtrate obtained in the step (4) for dewatering and impurity removal, crystallizing and separating out glycolide from the concentrated solution, and then carrying out centrifugal separation and drying to obtain high-purity glycolide.
Further, the organic solvent used in the dissolution of the crude product in the step (1) is any one of dichloromethane, ethyl acetate and butyl acetate, and the extractant used in the liquid-liquid extraction in the step (2) is water.
Furthermore, in the liquid-liquid extraction in the step (2), the addition amount of the extracting agent is 1/5-1/2 of the volume of the solution.
Further, in the step (2), in the liquid-liquid extraction, the contact time of the dissolving solution and the extracting agent is not more than 1h, and the temperature of the extracting agent is not more than 10 ℃.
Further, in the step (4) of removing water and impurities, anhydrous inorganic salt is added into the organic phase obtained in the step (3) of separating the two phases, and then the inorganic salt and the residual impurities after water absorption are filtered by filter cloth.
Further, in the step (4) of removing water and impurities, a molecular sieve is added into the organic phase obtained in the step (3) of separating the two phases, and then the molecular sieve after water absorption and the residual impurities are filtered out through a filter cloth.
Furthermore, the filter cloth has a filter diameter of 0.1-4 μm.
Further, in the (5) distillation crystallization, mother liquor generated by distillation is returned to the crude product dissolution in the step (1) for dissolving crude glycolide.
The invention has the advantages that:
dissolving crude glycolide, wherein the selected organic solvent is a good solvent of glycolide and a poor solvent of impurities, so that the glycolide in the crude glycolide is dissolved in the organic solvent; then, transferring glycolic acid, a small amount of glycolic acid dimer and glycolic acid trimer and a small amount of glycolic acid tetramer impurities in the by-products into an extracting agent phase by liquid-liquid extraction; then, through two-phase separation, impurities dissolved in the extracting agent can be removed along with the separated extracting agent phase; adding inorganic salt (anhydrous magnesium sulfate or anhydrous sodium sulfate) or molecular sieve into the separated organic phase to adsorb water, and filtering with small filter diameter filter cloth to remove the inorganic salt and molecular sieve after water absorption and impurities such as glycolic acid dimer, glycolic acid trimer and glycolic acid tetramer which are not dissolved in the extractant, thereby realizing dehydration and impurity removal effects, further improving the purity of glycolide products and reducing the acid value of the glycolide products; finally, the high-purity glycolide product with greatly improved purity can be obtained by distillation, concentration, centrifugation and drying.
The specific implementation mode is as follows:
the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
a process for the purification of glycolide, comprising the steps of:
(1) dissolving a crude product: dissolving 120g of crude glycolide with an acid value of 620mmol/kg and a purity of 92.6 percent in 2000ml of dichloromethane, stirring for dissolution, controlling the temperature to be about 25 ℃ to obtain a solution in which the glycolide is dissolved, and keeping the whole dissolution process in a sealed state;
(2) liquid-liquid extraction: adding 600ml of ultrapure water into the dissolved solution obtained in the step (1) crude product dissolution, fully stirring for 2min, standing for 2min to obtain a mixed solution, and transferring glycolic acid, a small amount of glycolic acid dimer and glycolic acid trimer and a trace amount of glycolic acid tetramer impurities in the by-product into the water phase; the contact time of the dissolving solution and the ultrapure water is not more than 1h, and the temperature of the ultrapure water is not more than 10 ℃, so that the glycolide can be prevented from being hydrolyzed.
(3) Two-phase separation: separating the mixed liquid obtained in the liquid-liquid extraction in the step (2) by an extraction centrifuge to obtain a water phase and an organic phase, and removing water-soluble impurities along with the separated water phase; the centrifugation time was 10 min.
(4) Dewatering and impurity removal: dehydrating the organic phase obtained in the step (3) and separating the two phases, and removing insoluble solid particles contained in the organic phase to obtain glycolide filtrate;
specifically, 100g of anhydrous sodium sulfate is added into the organic phase obtained in the two-phase separation in the step (3), and the mixture is stirred for 30 min; thereafter, sodium sulfate after water absorption and glycolic acid dimer, glycolic acid trimer, and glycolic acid tetramer impurities which were not dissolved in the extractant were filtered off through a filter cloth. The filter cloth has a filter diameter of 0.1-4 μm.
(5) Distillation and crystallization: transferring the glycolide filtrate obtained in the step (4) for dewatering and impurity removal into a distillation flask of a reduced pressure distillation device for reduced pressure distillation and concentration, crystallizing and separating out glycolide from the concentrated solution under the conditions that the temperature is less than or equal to 25 ℃ and the vacuum degree is less than or equal to-0.08 MPa, transferring the solid product after centrifugal separation into a vacuum drying oven, and drying for 30min under the conditions that the temperature is 25 ℃ and the vacuum degree is-0.08 MPa to obtain the high-purity glycolide product, wherein the acid value is 0.1mmol/kg, the purity is 99.89%, and the yield is 76%.
Example 2:
a process for the purification of glycolide, comprising the steps of:
(1) dissolving a crude product: dissolving 120g of crude glycolide with an acid value of 620mmol/kg and a purity of 92.6 percent in 2000ml of ethyl acetate, stirring for dissolution, controlling the temperature to be about 25 ℃ to obtain a solution in which the glycolide is dissolved, and keeping the whole dissolution process in a sealed state;
(2) liquid-liquid extraction: adding 600ml of ultrapure water into the dissolved solution obtained in the step (1) crude product dissolution, fully stirring for 2min, standing for 2min to obtain a mixed solution, and transferring glycolic acid, a small amount of glycolic acid dimer and glycolic acid trimer and a trace amount of glycolic acid tetramer impurities in the by-product into the water phase; the contact time of the dissolving solution and the ultrapure water is not more than 1h, and the temperature of the ultrapure water is not more than 10 ℃, so that the glycolide can be prevented from being hydrolyzed.
(3) Two-phase separation: separating the mixed liquid obtained in the liquid-liquid extraction in the step (2) by an extraction centrifuge to obtain a water phase and an organic phase, and removing water-soluble impurities along with the separated water phase; the centrifugation time was 10 min.
(4) Dewatering and impurity removal: dehydrating the organic phase obtained in the step (3) and separating the two phases, and removing insoluble solid particles contained in the organic phase to obtain glycolide filtrate;
specifically, 100g of anhydrous sodium sulfate is added into the organic phase obtained in the two-phase separation in the step (3), and the mixture is stirred for 30 min; thereafter, impurities such as sodium sulfate after water absorption and glycolic acid dimer, glycolic acid trimer, glycolic acid tetramer, etc., which are not dissolved in the extractant, were filtered off through a filter cloth. The filter cloth has a filter diameter of 0.1-4 μm.
(5) Distillation and crystallization: transferring the glycolide filtrate obtained in the step (4) for dehydration and impurity removal into a distillation flask of a vacuum distillation device for vacuum distillation and concentration, crystallizing and separating out glycolide from the concentrated solution under the conditions that the temperature is less than or equal to 25 ℃ and the vacuum degree is less than or equal to-0.08 MPa, transferring the solid product obtained after centrifugal separation into a vacuum drying oven, and drying for 30min under the conditions that the temperature is 25 ℃ and the vacuum degree is-0.08 MPa to obtain a high-purity glycolide product, wherein the acid value is 0.3mmol/kg, the purity is 99.87%, and the yield is 73.1% through determination.
Example 3:
a process for the purification of glycolide, comprising the steps of:
(1) dissolving a crude product: dissolving 120g of crude glycolide with an acid value of 620mmol/kg and a purity of 92.6 percent in 2000ml of butyl acetate, stirring for dissolution, controlling the temperature to be about 25 ℃ to obtain a dissolved solution in which the glycolide is dissolved, and keeping the whole dissolution process in a sealed state;
(2) liquid-liquid extraction: adding 600ml of ultrapure water into the dissolved solution obtained in the step (1) crude product dissolution, fully stirring for 2min, standing for 2min to obtain a mixed solution, and transferring glycolic acid, a small amount of glycolic acid dimer and glycolic acid trimer and a trace amount of glycolic acid tetramer impurities in the by-product into the water phase; the contact time of the dissolving solution and the ultrapure water is not more than 1h, and the temperature of the ultrapure water is not more than 10 ℃, so that the glycolide can be prevented from being hydrolyzed.
(3) Two-phase separation: separating the mixed liquid obtained in the liquid-liquid extraction in the step (2) by a centrifugal machine to obtain a water phase and an organic phase, and removing water-soluble impurities along with the separated water phase; the centrifugation time was 10 min.
(4) Dewatering and impurity removal: dehydrating the organic phase obtained in the step (3) and separating the two phases, and removing insoluble solid particles contained in the organic phase to obtain glycolide filtrate;
specifically, 100g of molecular sieve A4 is added into the organic phase obtained in the two-phase separation in the step (3), and the mixture is stirred for 30 min; then, the molecular sieve a4 after water absorption and impurities such as glycolic acid dimer, glycolic acid trimer, glycolic acid tetramer, etc. which are not dissolved in the extractant were filtered off through a filter cloth. The filter cloth has a filter diameter of 0.1-4 μm.
(5) Distillation and crystallization: transferring the glycolide filtrate obtained in the step (4) for dehydration and impurity removal into a distillation flask of a vacuum distillation device for vacuum distillation and concentration, crystallizing and separating out glycolide from the concentrated solution under the conditions that the temperature is less than or equal to 25 ℃ and the vacuum degree is less than or equal to-0.08 MPa, transferring the solid product obtained after centrifugal separation into a vacuum drying oven, and drying for 30min under the conditions that the temperature is 25 ℃ and the vacuum degree is-0.08 MPa to obtain the high-purity glycolide product, wherein the acid value is 0.4mmol/kg, the purity is 99.82%, and the yield is 74.2% through determination.
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, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (8)
1. A process for purifying glycolide, comprising the steps of:
(1) dissolving a crude product: dissolving crude glycolide in an organic solvent to obtain a dissolved solution;
(2) liquid-liquid extraction: adding an extracting agent into a dissolving solution obtained in the step (1) crude product dissolving, and fully stirring to obtain a mixed solution;
(3) two-phase separation: separating the mixed liquid obtained in the liquid-liquid extraction in the step (2) by an extraction centrifuge to obtain an extractant phase and an organic phase;
(4) dewatering and impurity removal: dehydrating the organic phase obtained in the step (3) two-phase separation, and removing insoluble solid particles contained in the organic phase to obtain glycolide filtrate;
(5) distillation and crystallization: and (4) distilling and concentrating the glycolide filtrate obtained in the step (4) for dewatering and impurity removal, crystallizing and separating out glycolide from the concentrated solution, and then carrying out centrifugal separation and drying to obtain high-purity glycolide.
2. The glycolide purification process according to claim 1, wherein when the crude product in step (1) is dissolved, the organic solvent is any one of dichloromethane, ethyl acetate and butyl acetate, and the extractant in the liquid-liquid extraction in step (2) is water.
3. The glycolide purification process according to claim 1, wherein in the liquid-liquid extraction in the step (2), the addition amount of the extraction agent is 1/5-1/2 of the volume of the solution.
4. The glycolide purification process according to claim 1, wherein in the liquid-liquid extraction in the step (2), the contact time of the dissolving liquid and the extractant is not more than 1h, and the temperature of the extractant is not more than 10 ℃.
5. The glycolide purification process according to claim 1, wherein in the step (4) of removing water and impurities, anhydrous inorganic salt is added to the organic phase obtained in the step (3) of separating two phases, and then the inorganic salt and the residual impurities after water absorption are filtered out through a filter cloth.
6. The glycolide purification process according to claim 1, wherein in the step (4) of removing water and impurities, the molecular sieve is added into the organic phase obtained in the step (3) of two-phase separation, and then the molecular sieve after water absorption and the residual impurities are filtered out through a filter cloth.
7. A process for the purification of glycolide according to claim 5 or 6, wherein the filter cloth has a filter diameter of 0.1 to 4 μm.
8. The glycolide purification process according to claim 1, wherein in the step (5) of distillation crystallization, mother liquor generated by distillation is returned to the crude product dissolution in the step (1) for dissolving crude glycolide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111502229.1A CN114014835A (en) | 2021-12-09 | 2021-12-09 | Glycolide purification process |
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| CN202111502229.1A CN114014835A (en) | 2021-12-09 | 2021-12-09 | Glycolide purification process |
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| CN114014835A true CN114014835A (en) | 2022-02-08 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114853718A (en) * | 2022-05-05 | 2022-08-05 | 广东粤港澳大湾区黄埔材料研究院 | Method for purifying L-lactide |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106397388A (en) * | 2016-09-07 | 2017-02-15 | 南京大学 | Process of preparing high-purity cyclic ester through purifying cyclic ester crude product |
| CN107304196A (en) * | 2016-04-19 | 2017-10-31 | 上海浦景化工技术股份有限公司 | A kind of method of vacuum distillation-refined glycolide of fusion-crystallization coupling |
| CN107868074A (en) * | 2016-09-26 | 2018-04-03 | 中国石油化工股份有限公司 | The method of purification of glycolide |
| CN111087381A (en) * | 2018-10-23 | 2020-05-01 | 中国石油化工股份有限公司 | Refining treatment method of glycolide |
-
2021
- 2021-12-09 CN CN202111502229.1A patent/CN114014835A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107304196A (en) * | 2016-04-19 | 2017-10-31 | 上海浦景化工技术股份有限公司 | A kind of method of vacuum distillation-refined glycolide of fusion-crystallization coupling |
| CN106397388A (en) * | 2016-09-07 | 2017-02-15 | 南京大学 | Process of preparing high-purity cyclic ester through purifying cyclic ester crude product |
| CN107868074A (en) * | 2016-09-26 | 2018-04-03 | 中国石油化工股份有限公司 | The method of purification of glycolide |
| CN111087381A (en) * | 2018-10-23 | 2020-05-01 | 中国石油化工股份有限公司 | Refining treatment method of glycolide |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114853718A (en) * | 2022-05-05 | 2022-08-05 | 广东粤港澳大湾区黄埔材料研究院 | Method for purifying L-lactide |
| CN114853718B (en) * | 2022-05-05 | 2024-03-26 | 广东粤港澳大湾区黄埔材料研究院 | Purification method of L-lactide |
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