CN101845038A - Method and device for processing lactide refined raffinate - Google Patents
Method and device for processing lactide refined raffinate Download PDFInfo
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Abstract
The invention relates to a method for processing lactide refined raffinate and a processing device adopting the same. The method comprises the following steps of: (1) heating and flashing lactide refined raffinate to remove heavy components containing oligomers in the refined raffinate, thereby obtaining flashing steam; (2) condensing the flashing steam to obtain a flashing condensate; (3) extracting the flashing condensate by using water as an extractant to make m-lactide blend in a liquid phase and separate out L-lactide as a solid phase, thereby forming a solid and liquid-phase system; and (4) separating the solid and liquid-phase system to obtain a wet filter cake and filtrate. The processing device comprises a flashing device, a condensation, an extraction device, a solid-liquid separation device and a melting device which are connected mutually. The invention has the advantages of reasonable process, simple device and flexible operation mode, effectively realizes the yield separation and recycling of the oligomers, the m-lactide, lactic acid and the L-lactide, improves the total yield of the L-lactide, and is mainly used for a PLA synthesis process of an indirect-polymerization two-step method.
Description
Technical field
The present invention relates to a kind of lactide refined raffinate treatment process and utilize the lactide refined raffinate treatment unit of this method, belong to chemical field, be mainly used in PLA (poly(lactic acid)) synthesis technique of indirect polymerized two-step approach.
Background technology
Poly(lactic acid) (PLA) is to be the high molecular polymer that raw material makes with lactic acid (LA).LA can make with biomass material (as cereal such as corns), and biomass material is renewable, and the product P LA of LA is biodegradable to be carbonic acid gas and water, so PLA is described as " green fiber ".
PLA synthetic operational path has two kinds: direct polymerization single stage method and indirect polymerized two-step approach.High molecular PLA is made by two-step approach (rac-Lactide ring-opening polymerization), and this technology generally comprises that acid by dehydrating lactic, pre-polymerization, oligopolymer depolymerization cyclisation, crude lactide are refining, rac-Lactide ring-opening polymerization and polymkeric substance take off master operations such as single.
Crude lactide mainly is made up of L-rac-Lactide (left-handed), m-rac-Lactide (meso), small amounts of oligomer, lactic acid and water etc., wherein the m-rac-Lactide is the isomers impurity of L-rac-Lactide, and under the environment of oligopolymer and water existence, thermolysis, isomerization reaction etc. take place easily, therefore, crude lactide is refining has than big difficulty.Crude lactide is refining can to adopt methods such as rectifying, fusion-crystallization, recrystallization, extraction, to make the rac-Lactide of purity 〉=99.5% (wt).Fusion-crystallization is generally operated near the fusing point of crystallographic component, and service temperature is low, does not need other auxiliary agents or solvent, and energy consumption is low, and environmental protection is suitable for the purification that has thermo-sensitivity and contain the crude lactide of isomers impurity.In lactide refined technology, the refined raffinate amount that adopts the fusion-crystallization technology to produce is 15～25% (wt) of crude lactide, and wherein rac-Lactide concentration is 55～65% (wt), therefore, must recycle lactide refined raffinate, to improve the total recovery of rac-Lactide.
Patent CN101555243A discloses a kind of preparation method and production equipment (referring to Fig. 1) of smart rac-Lactide, wherein relates to a kind of treatment technology of lactide refined raffinate.This technology is lactide refined raffinate to be carried out centrifugal thin film evaporation unit handle, evaporation separates the gas phase rac-Lactide that obtains and turns back in the condenser system of depolymerization cyclisation top, or after independent condenser system condensation, turn back to lactide refined operation, and the residue that the evaporation separation obtains turns back to the pre-polymerization operation, or turn back to depolymerization cyclisation operation, or judge under the situation that is unfavorable for improving the rac-Lactide yield owing to foreign matter content is too high discarded.
The problem that this technology exists is:
1, do not consider the processing or the separation of isomer impurities m-rac-Lactide in the process, cause the accumulation of component m-rac-Lactide in depolymerization cyclisation, the lactide refined and raffinate evaporation tripping device, increased the energy expenditure in the process;
2, the isolating residue of periodic discharging evaporation causes the flow and the periodical change of component concentration that enter depolymerization cyclisation, lactide refined and evaporation tripping device, is unfavorable for the steady running of production system.
Summary of the invention
For overcoming the defective of prior art, the invention provides a kind of lactide refined raffinate treatment process and device, this method and apparatus can be removed the m-rac-Lactide in the lactide refined raffinate effectively, to reach with the abundant reuse of refined raffinate, improve the rac-Lactide yield, and do not influence the steady running of production system.
The objective of the invention is to be achieved through the following technical solutions:
A kind of lactide refined raffinate treatment process, it may further comprise the steps: (1) heating flash evaporation lactide refined raffinate, remove the heavy component that comprises oligopolymer in the described refined raffinate, obtain flash vapors; (2) the described flash vapors of condensation obtains the flash distillation lime set; (3) be that extraction agent extracts described flash distillation lime set with water, make m-rac-Lactide wherein incorporate liquid phase, the L-rac-Lactide is separated out becomes solid phase, forms the solid-liquid two-phase system; (4) the described solid-liquid two-phase system of solid-liquid separation obtains wet cake and filtrate.
The vaporization temperature of described step (1) is preferably 200～250 ℃, and evaporating pressure is preferably 5～15mmHg.
The water collection temperature of described step (3) is preferably 10 ℃～50 ℃, and the water collection is preferably 1: 2～3: 1 than (mass ratio between extraction water and the flash distillation lime set), and the residence time is preferably 10min～60min.
Usually, the heavy component that described step (1) obtains can be returned the utilization of depolymerization cyclisation operation.
Noncondensable gas in the described step (2) can be extracted out by vacuum system.
The filtrate that described step (4) obtains can be sent into dehydration enrichment process recycling water soluble organic substance wherein.
Return the utilization of pre-polymerization operation after the wet cake fusing that described step (4) can be obtained.
In addition, can be according to rac-Lactide isomer impurities concentration in the crude lactide that makes in the PLA synthesis technique and oligomer concentrations different, adopt following different mode to handle to corresponding lactide refined raffinate:
(1) if in the crude lactide that makes isomer impurities exceed standard but oligopolymer seldom, then stride across described step (1) and step (2), directly enter described step (3), adopting water is that extraction agent directly extracts lactide refined raffinate;
(2) if isomer impurities does not exceed standard in the crude lactide that makes, after then passing through the processing of described step (1) and step (2), no longer carry out the processing of step (3) and step (4), the heavy component that described step (1) is obtained returns the utilization of depolymerization cyclization process, and the material that removes behind the heavy component is returned the utilization of pre-polymerization operation;
(3), then carry out the whole process of described step (1), step (2), step (3) and step (4) successively and handle if isomer impurities concentration in the crude lactide that makes and oligomer concentrations are all high.
A kind of lactide refined raffinate treatment unit that adopts aforesaid method, it comprises flash distillation plant, condensing works, extraction plant and equipment for separating liquid from solid, described flash distillation plant is provided with treats the flash distillation material inlet, flash vapors outlet and heavy component outlet, described condensing works is provided with treats the condensation material inlet, lime set outlet and noncondensable gas outlet, described extraction plant is provided with material inlet to be extracted, extraction agent import and the outlet of extraction disposed slurry, described equipment for separating liquid from solid is provided with material import to be separated, filtered solid outlet and filtrate outlet, what the outlet of the flash vapors of described flash distillation plant connected described condensing works treats the condensation material inlet, what the outlet of the lime set of described condensing works connected described extraction plant treats the extraction liquid import, and the extraction disposed slurry outlet of described extraction plant connects the material import to be separated of described equipment for separating liquid from solid.
Described flash distillation plant preferably adopts luwa evaporator.
Preferably, be provided with gas-liquid separation device in the described condensing works, described noncondensable gas outlet connects the bleeding point of vacuum system.
Described extraction plant preferably adopts extraction kettle, describedly treat that extraction liquid import and described extraction agent import are separately positioned on the top and/or the top of described extraction kettle, described extraction disposed slurry outlet is arranged on the bottom or the bottom of described extraction kettle, is provided with agitator in the described extraction kettle.
Generally should be provided with pump on the connecting tube between the extraction disposed slurry outlet of described extraction plant and the material import to be separated of described equipment for separating liquid from solid, the whizzer that described equipment for separating liquid from solid can adopt solid-liquid separation to use, described filtered solid outlet can connect melting pot by material transport mechanism usually, and described filtrate outlet can connect filtrate tank usually.
The invention has the beneficial effects as follows: the present invention utilizes isomer impurities m-rac-Lactide and then is difficult to be dissolved in principle in the water than being easier to water-soluble and hydrolysis L-rac-Lactide taking place, mode by the water extraction is separated the m-rac-Lactide, thereby avoided the m-rac-Lactide in system accumulation and in treating processes the mass consumption of energy, experiment according to the applicant, after adopting the present invention, the clearance of isomer impurities m-rac-Lactide can reach 90%～95%; Because can returning in the corresponding operation of PLA synthesis system, the various materials of separating by each steps such as flash distillation, condensation, water extraction, solid-liquid separation carry out reuse, reduced material quantity discharged, improved the total recovery of rac-Lactide greatly, experiment according to the applicant, after adopting the present invention, the total recovery of L-rac-Lactide is compared with prior art can improve 5%～10%; Because treatment system can realize successive work, can guarantee the steady running of whole PLA synthetic system; Because adopting water in extraction is extraction agent, the extraction conditions gentleness realizes through engineering approaches easily, helps simplifying technological process, reduces production costs.
Description of drawings
Fig. 1 is the process flow sheet that lactide refined raffinate is handled among the CN101555243A.
Fig. 2 is the process flow sheet that lactide refined raffinate of the present invention is handled.
Embodiment
Referring to Fig. 2, lactide refined raffinate treatment process provided by the invention and the lactide refined raffinate treatment unit that utilizes described method, effectively oligopolymer, m-rac-Lactide and L-rac-Lactide are separated from each other and can return respectively in the suitable operation of PLA synthetic and be used, reach the abundant recycling of refined raffinate and reduce the purpose that material discharges, improved L-rac-Lactide yield effectively, and can the steady running of PLA synthesis system not had a negative impact, possess suitability preferably.
The present invention at first carries out heating flash evaporation to lactide refined raffinate in flash distillation plant, flash distillation plant can adopt luwa evaporator and other flashing apparatuss, wherein a kind of preferably luwa evaporator, the luwa evaporator heat transfer coefficient is big, the evaporation capacity height is adapted to the flash distillation operation of raffinate among the present invention especially.Under existing PLA synthetic technology, the content of sending into rac-Lactide in the refined raffinate of flash distillation plant can reach 55～65% (wt), need wherein m-rac-Lactide, L-rac-Lactide and other separating substances of different nature are come, so that carry out different recyclings respectively, to be used.Owing to contain certain oligopolymer usually in the raffinate, vaporization temperature in the flash distillation operation can be controlled at 200 ℃～250 ℃, such as 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃ or 250 ℃, evaporating pressure can be controlled at 5mmHg～15mmHg, such as 5mmHg, 7mmHg, 9mmHg, 11mmHg, 13mmHg or 15mmHg.Usually, flash distillation plant is provided with treats flash distillation material inlet, flash vapors outlet and heavy component outlet, under above-mentioned processing parameter, oligopolymer in the raffinate etc. form heavy component, discharge from the heavy component outlet of flash distillation plant bottom, separate heavy component and can return depolymerization cyclisation operation wherein oligopolymer is used, the flash vapors that contains m-rac-Lactide and L-rac-Lactide etc. is discharged from the flash vapors outlet at flash distillation plant top, in condensing works, carry out condensation process by pipe-line transportation.
Described condensing works is provided with treats condensation material inlet, lime set outlet and noncondensable gas outlet, the outlet of the flash vapors of flash distillation plant is treated the condensation material inlet by the pipe connection condensing works, flash vapors is from treating that the condensation material inlet enters condensing works, through condensation, rac-Lactide in the flash vapors, lactic acid and other organic components are condensed into liquid phase, constitute the flash distillation lime set, send into extraction plant from lime set outlet discharge and by pipeline, noncondensable gas can be drawn out of from the noncondensable gas outlet by vacuum system.
Impurity in the described flash distillation lime set mainly comprises m-rac-Lactide and lactic acid, in order further to remove these impurity, the described flash distillation lime set that enters extraction kettle is extracted.Because isomer impurities m-rac-Lactide ratio is easier to be dissolved in the water and hydrolysis takes place, the L-rac-Lactide then is difficult to be dissolved in the water, and therefore by the water extraction, isomer impurities m-rac-Lactide is dissolved in the water, and lactic acid is also soluble in water simultaneously, forms liquid phase.Overwhelming majority L-rac-Lactide is separated out with solid phase, has formed the solid-liquid two-phase system in the extraction kettle, by follow-up solid-liquid separation, just the L-rac-Lactide can be separated with m-rac-Lactide and lactic acid.
Described extraction plant can adopt extraction kettle, extraction tower or other suitable extraction equipments, and the housing top of described extraction plant can be provided with described treat extraction liquid import and extraction agent import, and the bottom can be provided with described extraction disposed slurry outlet.Described extraction agent adopts the water at low temperature of optimal temperature, and the temperature of described extraction can be 10 ℃～50 ℃, such as 10 ℃, 20 ℃, 30 ℃, 40 ℃ or 50 ℃; The water collection can be 1: 2～3: 1 usually than (the extraction water is with the mass ratio of flash distillation lime set), such as 1: 2,1: 1,3: 2,2: 1,5: 2 or 3: 1, the residence time can be 10min～60min, such as 10min, 20min, 30min, 40min, 50min or 60min, to reach good effect of extracting.Described flash distillation lime set enters extraction kettle from the extraction liquid import for the treatment of of described extraction kettle, extraction agent import (being the water at low temperature import) by described extraction kettle enters extraction kettle as the water at low temperature of extraction agent, and described solid-liquid two-phase system (extraction disposed slurry) can be discharged from the extraction disposed slurry outlet of described extraction kettle.
For described solid-liquid two-phase system is carried out solid-liquid separation, described solid-liquid two-phase system enters equipment for separating liquid from solid after discharging from extraction plants such as described extraction kettle.On the connecting tube of described extraction plant and equipment for separating liquid from solid, pump is set, described extraction disposed slurry is transported to described equipment for separating liquid from solid by pump.
Described equipment for separating liquid from solid can adopt the prior art or the other technologies of any suitable, rotary drum filter-press etc. for example, these equipment for separating liquid from solid are typically provided with material import to be separated, filtered solid outlet and filtrate outlet, the extraction disposed slurry can be separated into filter cake that contains the L-rac-Lactide and the filtrate of containing m-rac-Lactide, lactic acid.Described wet cake can be sent into melting appartus from the filtered solid outlet discharge and by the material transport mechanism of suitable structure, and described filtrate can be sent into the filtrate collection device from described filtrate outlet discharge and by modes such as pipelines.
Comprise most L-rac-Lactide in the wet cake that described equipment for separating liquid from solid produces, in order to realize the reuse of these L-rac-Lactides, wet cake further need be melted, therefore, wet cake is admitted to melting appartus and melts after the filtered solid outlet of described equipment for separating liquid from solid is discharged, the wet cake after the fusing can be used by the pre-polymerization operation that the mode of adaptations such as pipeline is sent into the PLA synthesis system.Described melting appartus can adopt the prior art or the other technologies of any suitable, for example possesses the melting pot of heating unit, and described melting appartus inside can be provided with agitator to improve the fusing effect.
Contain water-soluble organic components such as m-rac-Lactide and lactic acid in the described filtrate, in order to reach the recycling of these organic components, filtrate can be collected in the filtrate collection device after described equipment for separating liquid from solid is discharged, and is used so that continue to send into PLA synthetic dehydration enrichment process.Described filtrate collection device can adopt prior art or other technologies arbitrarily, for example filtrate tank, reservoir or other suitable equipment.
Main technique flow process of the present invention is: be admitted to flash distillation plants such as luwa evaporator from the lactide refined raffinate of PLA synthesis system and carry out heating flash evaporation, the flash vapors that obtains is discharged and is sent in the condenser from the flash vapors outlet of described luwa evaporator, flash distillation in the luwa evaporator removes thing heavy components such as () oligopolymer and discharges and collect through the heavy component outlet of described luwa evaporator, the flash vapors that enters described luwa evaporator condenser is condensed, m-rac-Lactide wherein, L-rac-Lactide and lactic acid enter liquid phase, constitute lime set, the vacuum system that noncondensable gas is linked to each other with described luwa evaporator condenser is extracted out, lime set further is admitted to extraction kettle, adopt the water extraction herein, m-rac-Lactide and lactic acid dissolution become liquid phase in water in described water collection still, the L-rac-Lactide is insoluble in water and is separated out and become solid phase, thereby constitute the solid-liquid two-phase system, for the L-rac-Lactide is effectively separated with major impurity (comprising m-rac-Lactide and lactic acid), described solid-liquid two-phase from the extraction disposed slurry outlet of described water collection still discharge and by pump delivery to whizzer, obtain wet cake and filtrate through solid-liquid separation, isolating wet cake contains a large amount of L-rac-Lactides, being admitted to melting pot melts with standby, separated filtrate contains a large amount of organic components, and liquor collecting device (filtrate tank) is collected with reuse after filtration.
Can be according to rac-Lactide isomer impurities concentration in the crude lactide that makes in the PLA synthesis technique and oligomer concentrations different, select part processing step wherein to handle accordingly, and omit wherein unwanted step, for example:
(1) if in the crude lactide that makes isomer impurities exceed standard but oligopolymer seldom, contained oligopolymer has a negative impact can for operation, yield and the quality product of PLA synthesis system, then can stride across described step (1) and step (2), directly enter described step (3), adopting water is that extraction agent directly extracts lactide refined raffinate;
(2) if isomer impurities does not exceed standard in the crude lactide that makes, contained m-rac-Lactide has a negative impact can for operation, yield and the quality product of PLA synthesis system, after then passing through the processing of described step (1) and step (2), no longer carry out the processing of step (3) and step (4), the heavy component that described step (1) is obtained returns the utilization of depolymerization cyclization process, and the material that removes behind the heavy component is returned the utilization of pre-polymerization operation;
(3) if isomer impurities concentration in the crude lactide that makes and oligomer concentrations are all high, do not separate out operation, yield and/or the quality product that can influence the PLA synthesis system and have a negative impact, then should carry out the whole process of described step (1), step (2), step (3) and step (4) successively and handle.
Claims (10)
1. lactide refined raffinate treatment process is characterized in that may further comprise the steps: (1) heating flash evaporation lactide refined raffinate, remove the heavy component that comprises oligopolymer in the described refined raffinate, and obtain flash vapors; (2) the described flash vapors of condensation obtains the flash distillation lime set; (3) be that extraction agent extracts described flash distillation lime set with water, make m-rac-Lactide wherein incorporate liquid phase, the L-rac-Lactide is separated out becomes solid phase, forms the solid-liquid two-phase system; (4) the described solid-liquid two-phase system of solid-liquid separation obtains wet cake and filtrate.
2. lactide refined raffinate treatment process as claimed in claim 1, the vaporization temperature that it is characterized in that described step (1) is 200～250 ℃, evaporating pressure is 5～15mmHg.
3. lactide refined raffinate treatment process as claimed in claim 1 is characterized in that the water collection temperature of described step (3) is 10 ℃～50 ℃, and water comes together than being 1: 2～3: 1, and the residence time is 10min～60min.
4. as claim 1,2 or 3 described lactide refined raffinate treatment processs, it is characterized in that the heavy component that described step (1) obtains is returned the utilization of depolymerization cyclisation operation, noncondensable gas in the described step (2) is extracted out by vacuum system, the filtrate that described step (4) obtains is sent into dehydration enrichment process recycling water soluble organic substance wherein, return the utilization of pre-polymerization operation after the wet cake fusing with described step (4) acquisition.
5. lactide refined raffinate treatment process as claimed in claim 4, it is characterized in that different according to rac-Lactide isomer impurities concentration in the crude lactide that makes in the PLA synthesis technique and oligomer concentrations, adopt following different mode to handle corresponding lactide refined raffinate:
(1) if in the crude lactide that makes isomer impurities exceed standard but oligopolymer seldom, then stride across described step (1) and step (2), directly enter described step (3), adopting water is that extraction agent directly extracts lactide refined raffinate;
(2) if isomer impurities does not exceed standard in the crude lactide that makes, after then passing through the processing of described step (1) and step (2), no longer carry out the processing of step (3) and step (4), the heavy component that described step (1) is obtained returns the utilization of depolymerization cyclization process, and the material that removes behind the heavy component is returned the utilization of pre-polymerization operation;
(3), then carry out the whole process of described step (1), step (2), step (3) and step (4) successively and handle if isomer impurities concentration in the crude lactide that makes and oligomer concentrations are all high.
6. lactide refined raffinate treatment unit that utilizes the described method of claim 1, it is characterized in that comprising flash distillation plant, condensing works, extraction plant and equipment for separating liquid from solid, described flash distillation plant is provided with treats the flash distillation material inlet, flash vapors outlet and heavy component outlet, described condensing works is provided with treats the condensation material inlet, lime set outlet and noncondensable gas outlet, described extraction plant is provided with material inlet to be extracted, extraction agent import and the outlet of extraction disposed slurry, described equipment for separating liquid from solid is provided with material import to be separated, filtered solid outlet and filtrate outlet, what the outlet of the flash vapors of described flash distillation plant connected described condensing works treats the condensation material inlet, what the outlet of the lime set of described condensing works connected described extraction plant treats the extraction liquid import, and the extraction disposed slurry outlet of described extraction plant connects the material import to be separated of described equipment for separating liquid from solid.
7. lactide refined raffinate treatment unit as claimed in claim 6 is characterized in that described flash distillation plant adopts luwa evaporator.
8. lactide refined raffinate treatment unit as claimed in claim 7 is characterized in that being provided with gas-liquid separation device in the described condensing works, and described noncondensable gas outlet connects the bleeding point of vacuum system.
9. lactide refined raffinate treatment unit as claimed in claim 8, it is characterized in that described extraction plant adopts extraction kettle, describedly treat that extraction liquid import and described extraction agent import are separately positioned on the top and/or the top of described extraction kettle, described extraction disposed slurry outlet is arranged on the bottom or the bottom of described extraction kettle, is provided with agitator in the described extraction kettle.
10. as claim 6,7,8 or 9 described lactide refined raffinate treatment unit, it is characterized in that the connecting tube between the material import to be separated of the extraction disposed slurry outlet of described extraction plant and described equipment for separating liquid from solid is provided with pump, the whizzer that described equipment for separating liquid from solid adopts solid-liquid separation to use, described filtered solid outlet connects melting pot by material transport mechanism, and described filtrate outlet connects filtrate tank.
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| CN201010171115.9A CN101845038B (en) | 2010-05-13 | 2010-05-13 | Method and device for processing lactide refined raffinate |
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| CN201010171115.9A CN101845038B (en) | 2010-05-13 | 2010-05-13 | Method and device for processing lactide refined raffinate |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110496575A (en) * | 2019-07-17 | 2019-11-26 | 江苏新东风化工科技有限公司 | A kind of esterification production after-treatment system and its treatment process |
| CN111548339A (en) * | 2020-04-10 | 2020-08-18 | 深圳光华伟业股份有限公司 | Process for preparing glycolide from glycollate |
| CN111693559A (en) * | 2020-06-22 | 2020-09-22 | 中国核动力研究设计院 | Vapor droplet mass flow separation measuring device and method for gas-phase mixture |
| CN116199664A (en) * | 2021-11-30 | 2023-06-02 | 万华化学集团股份有限公司 | Method for separating and purifying lactide from crude lactide |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1112559A (en) * | 1993-12-08 | 1995-11-29 | 株式会社武藏野化学研究所 | Method for purification of lactide |
| CN101555243A (en) * | 2008-04-11 | 2009-10-14 | 株式会社日立工业设备技术 | Manufacturing method and device of cyclic refined lactic acid dimmer and manufacturing method and device of polylactic acid |
-
2010
- 2010-05-13 CN CN201010171115.9A patent/CN101845038B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1112559A (en) * | 1993-12-08 | 1995-11-29 | 株式会社武藏野化学研究所 | Method for purification of lactide |
| CN101555243A (en) * | 2008-04-11 | 2009-10-14 | 株式会社日立工业设备技术 | Manufacturing method and device of cyclic refined lactic acid dimmer and manufacturing method and device of polylactic acid |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110496575A (en) * | 2019-07-17 | 2019-11-26 | 江苏新东风化工科技有限公司 | A kind of esterification production after-treatment system and its treatment process |
| CN111548339A (en) * | 2020-04-10 | 2020-08-18 | 深圳光华伟业股份有限公司 | Process for preparing glycolide from glycollate |
| CN111693559A (en) * | 2020-06-22 | 2020-09-22 | 中国核动力研究设计院 | Vapor droplet mass flow separation measuring device and method for gas-phase mixture |
| CN111693559B (en) * | 2020-06-22 | 2022-04-01 | 中国核动力研究设计院 | Vapor droplet mass flow separation measuring device and method for gas-phase mixture |
| CN116199664A (en) * | 2021-11-30 | 2023-06-02 | 万华化学集团股份有限公司 | Method for separating and purifying lactide from crude lactide |
| CN116199664B (en) * | 2021-11-30 | 2024-10-18 | 万华化学集团股份有限公司 | Method for separating and purifying lactide from crude lactide |
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| Publication number | Publication date |
|---|---|
| CN101845038B (en) | 2014-01-15 |
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