CN111018810A - Device and method for continuously producing α -acetyl-gamma-butyrolactone - Google Patents
Device and method for continuously producing α -acetyl-gamma-butyrolactone Download PDFInfo
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- CN111018810A CN111018810A CN201911289323.6A CN201911289323A CN111018810A CN 111018810 A CN111018810 A CN 111018810A CN 201911289323 A CN201911289323 A CN 201911289323A CN 111018810 A CN111018810 A CN 111018810A
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- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/26—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member
- C07D307/30—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
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Abstract
The invention relates to a method for continuously producing α -acetyl-gamma-butyrolactone, which comprises the following steps of continuously adding gamma-butyrolactone, acetic ester and liquid metal sodium into a condensation reactor for condensation reaction, continuously transferring the condensation reaction liquid into a neutralization reactor, cooling, adding phosphoric acid for neutralization, transferring the neutralized solution into a phase separator by a pump for standing and phase separation, removing a water phase, transferring an oil phase into a distillation system for normal pressure distillation and reduced pressure distillation to obtain α -acetyl-gamma-butyrolactone.
Description
Technical Field
The invention relates to a production method of a medical intermediate, a pesticide intermediate and chemical raw materials, relates to a device and a method for continuously producing α -acetyl-gamma-butyrolactone, in particular to a continuous production method of α -acetyl-gamma-butyrolactone, and belongs to the technical field of chemical production and preparation.
Background
α -acetyl-gamma-butyrolactone is an important intermediate and organic chemical raw material for preparing vitamin and chlorophyll, and also is a medical intermediate for synthesizing antipsychotic drugs of risperidone, anticonvulsant and sedative hypnotic drugs of chloromethylthiazole, indomethacin and chloroquine, etc. at present, the method for preparing α -acetyl-gamma-butyrolactone mainly has two routes, one is a process using ethylene oxide and ethyl acetoacetate as starting materials, and the other is a process using gamma-butyrolactone and acetate as starting materials.
Among them, Chinese patent application documents (publication No. CN 1357545A), U.S. Pat. No. US 2443827, British patent GB 740993 and Japanese patent JP 4212662, etc. all disclose similar preparation methods for synthesizing α -acetyl-gamma-butyrolactone by using ethylene oxide and ethyl acetoacetate as starting materials, however, the yield of the process route is only about 70% at most, the cost is high, and the ethylene oxide as a reaction raw material belongs to a first-class flammable and explosive chemical, and has serious potential safety hazard in the processes of storage, transportation and reaction.
For example, Chinese patent application documents (publication No. CN 101230054A) and (publication No. CN 1548427A) disclose that gamma-butyrolactone and acetate are used as starting materials, benzene compounds are used as a reaction solvent, sodium metal or sodium alkoxide is used as a reaction catalyst, the raw materials and the catalyst are subjected to batch reaction in a reaction kettle, after the reaction is finished, acid is used for neutralization, an extracting agent is used for extraction, and an extract is rectified to obtain a final product. However, the process has the problems of over violent reaction, slow heat dissipation of a reaction kettle, difficult temperature control and the like, and accidents such as material flushing, combustion and the like are easy to occur in the production process, and a large amount of benzene solvents and waste acid generated by acidification in the production process can cause serious pollution to the environment.
As another example, Chinese patent application (publication No. CN 102030729A) discloses a method for synthesizing α -acetyl-gamma-butyrolactone without using benzene as a reaction solvent, wherein metallic sodium is added into the system at one time, and the acylation reaction rate is controlled by controlling the specific surface area of the metallic sodium.
While the Chinese patent application (publication No. CN 101768141A) adopts a method of adding a metallic sodium catalyst into a reaction system by times or continuously, which can effectively avoid potential safety hazards such as material flushing, combustion and the like caused by difficulty in controlling the reaction speed, toluene is used as an extracting agent, so that the toxicity is high, the separation is difficult, and the product quality is influenced by the residue of the toluene.
Chinese patent application document (publication number: CN 102229586A) reports that the contact area of a metallic sodium catalyst and reaction raw materials can be effectively increased by preparing metallic sodium into sodium sand, so that the catalytic efficiency of the metallic sodium is improved. However, molten metal sodium is rapidly cooled to 50-60 ℃ and is easy to agglomerate, so that the method is difficult to implement in industrial production, and meanwhile, a chlorine-containing solvent is used, so that the method has great pollution to the environment.
In addition, Chinese patent application document (publication No. CN 101092407A) discloses that α -acetyl-gamma-butyrolactone is synthesized by carrying out acylation reaction on ethyl acetate and gamma-butyrolactone through gas-phase catalysis of a fluorine-alkali solid-phase catalyst, although the potential safety hazard is solved, the cost is overhigh due to higher energy consumption, and certain potential hazard exists on product and environment pollution because solid alkali fluoride is used as the catalyst, and the solid alkali fluoride is not put into practical production and life at present.
Disclosure of Invention
The invention provides a device and a method for continuously producing α -acetyl-gamma-butyrolactone, aiming at solving the problems of low safety, poor reaction stability, large product quality fluctuation, low production efficiency and the like in the prior intermittent technology.
In order to solve the technical problem, the invention solves the technical scheme that the device for continuously producing α -acetyl-gamma-butyrolactone comprises:
the condensation reactor is used for carrying out condensation reaction on materials;
a neutralization reactor for adjusting the pH value and converting the sodium salt obtained by condensation into α -acetyl-gamma-butyrolactone;
the phase separator is used for standing and separating an organic phase and a water phase;
an atmospheric distillation system for continuous distillation to remove light components from the organic phase;
a vacuum rectification system for continuous rectification,
the condensation reactor, the neutralization reactor, the phase separator, the atmospheric distillation system and the vacuum distillation system are communicated in sequence.
In the device for continuously producing α -acetyl-gamma-butyrolactone, the condensation reactor comprises a microchannel reactor, a tank reactor, a loop reactor, and a series connection of the tank reactor and a tubular reactor.
In the continuous production device of α -acetyl-gamma-butyrolactone, a power pump for providing flow kinetic energy is also arranged between the neutralization reactor and the phase separator.
The invention also provides a method for continuously producing α -acetyl-gamma-butyrolactone, which comprises the following steps:
(1) simultaneously and continuously adding gamma-butyrolactone, acetate and liquid metal sodium into a condensation reactor for condensation reaction;
(2) after the condensation reaction is finished, continuously transferring the condensation reaction liquid into a neutralization reactor, cooling, and adding phosphoric acid for neutralization;
(3) transferring the neutralized solution into a phase separator by a pump, standing for phase separation, removing a water phase, transferring an oil phase into a distillation system, and distilling under normal pressure and reduced pressure to obtain α -acetyl-gamma-butyrolactone.
The invention adopts gamma-butyrolactone, acetic ester and liquid metal sodium to continuously enter a condensation reactor for continuous condensation reaction, the reaction liquid is continuously discharged and enters a neutralization reactor, and then is continuously neutralized by phosphoric acid, phase separation, normal pressure distillation and reduced pressure rectification to obtain a product, the process of the reaction is controlled by adjusting the flow of the gamma-butyrolactone, the acetic ester and the liquid metal sodium, a continuous production method and a production system are adopted, so that the reaction process is more stable and safer, the reaction control adopts automatic control, and the serious potential safety hazards of over-violent reaction, easy flushing and the like of the traditional intermittent production are avoided.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the molar mass ratio of gamma-butyrolactone to acetate is 1:1.5 to 5.0, and preferably, the molar mass ratio of gamma-butyrolactone to acetate is 1:2.0 to 4.0.
Preferably, the acetate is one or more of methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate and sec-butyl acetate.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the molar mass ratio of gamma-butyrolactone to liquid metal sodium is 1:0.8-1.5, and preferably, the molar mass ratio of gamma-butyrolactone to liquid metal sodium is 1: 1.0-1.3.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the condensation reaction temperature is preferably 60 to 100 ℃, and is preferably 75 to 90 ℃.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the residence time of the condensation reaction is 1-16 hours, preferably, the residence time of the condensation reaction is 8-10 hours, the residence time after the condensation reaction is finished is the reflux of the system, and in order to ensure the maximum yield of the finally obtained α -acetyl-gamma-butyrolactone.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the pressure of the condensation reaction is preferably 0 to 2.0MPa, and the pressure of the reaction is preferably 0 to 0.5 MPa.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the temperature of the neutralization reaction is 40-60 ℃, the mass concentration of phosphoric acid used in the neutralization reaction is 40-60%, and the molar ratio of the phosphoric acid used in the neutralization reaction to the gamma-butyrolactone is 0.4-1.2: 1, preferably, the molar ratio of the phosphoric acid to the gamma-butyrolactone is 0.7-0.9: 1.
In the method for continuously producing α -acetyl-gamma-butyrolactone, the temperature of reduced pressure rectification is 120-150 ℃, and the absolute pressure is 1-50 kPa.
Due to the adoption of the technical scheme, the invention has the remarkable technical effects that:
(1) the invention controls the reaction process by adjusting the flow of gamma-butyrolactone, acetic ester and liquid metal sodium, adopts a continuous production method, makes the reaction process more stable and safer, adopts automatic control for reaction control, avoids serious potential safety hazards such as over violent reaction, easy material flushing and the like of the traditional intermittent production, and simultaneously adopts the continuous production method, thereby being easier to realize sealing and automation, and having more stable reaction yield and product quality.
(2) The method does not need to adopt benzene substances as a reaction solvent or an extracting agent to extract the water phase, has relatively simple operation, eliminates a pollution source from the source, is green and environment-friendly, greatly reduces the production cost, improves the comprehensive economic benefit, and avoids the problems of environmental pollution, difficult separation and the like caused by the use of benzene substances as solvents in the traditional process.
(3) The molten metal sodium is added, so that the dripping speed can be better controlled, the condensation reaction rate can be better controlled, the instability of the condensation reaction caused by the aggregation of the one-time addition of the metal sodium is prevented, the potential safety hazard that the condensation reaction is too violent and the material is easy to flush in the traditional batch method is avoided, the condensation reaction time is reduced, the condensation reaction is completed along with the dripping completion of the molten liquid metal sodium, the condensation reaction process is accelerated, and the subsequent heat preservation is favorable for maximizing the yield of α -acetyl-gamma-butyrolactone.
Detailed Description
The present invention will be described in further detail with reference to examples.
As shown in fig. 1, the continuous production system for α -acetyl-gamma-butyrolactone according to the present invention comprises:
the condensation reactor is used for carrying out condensation reaction on materials;
a neutralization reactor for adjusting the pH value and converting the sodium salt obtained by condensation into α -acetyl-gamma-butyrolactone;
the phase separator is used for standing and separating an organic phase and a water phase;
an atmospheric distillation system for continuous distillation to remove light components from the organic phase;
a vacuum rectification system for continuous rectification,
the condensation reactor, the neutralization reactor, the phase separator, the atmospheric distillation system and the vacuum distillation system are communicated in sequence.
Further, the condensation reactor comprises a microchannel reactor, a kettle reactor, a loop reactor and a series connection of the kettle reactor and a tubular reactor.
Further, a power pump for providing circulation kinetic energy is arranged between the neutralization reactor and the phase separator.
Examples 1 to 29
Gamma-butyrolactone, ethyl acetate and liquid sodium metal are continuously added into a tubular reactor according to the molar ratios respectively described in examples 1-29 of table 1 to simultaneously carry out condensation reaction as described in example 1-29, hydrogen is continuously generated during the reaction process, the generated α -acetyl-gamma-butyrolactone sodium salt solution continuously enters a neutralization reactor through a pipeline, is continuously neutralized with a prepared phosphoric acid aqueous solution with the content of 50%, the molar ratio of the phosphoric acid to the gamma-butyrolactone is 0.8:1, the reacted materials continuously enter a phase separator through a pipeline from an outlet of the neutralization reactor to carry out phase separation, an organic phase and a water phase are separated, the organic phase from the phase separator is continuously distilled by an atmospheric distillation tower to remove light components, and the materials at the bottom of the tower are continuously pumped into a reduced pressure distillation tower to carry out continuous rectification, so that a α -acetyl-gamma-butyrolactone product is obtained.
Example 30: this embodiment is the same as embodiment 4 except that: the reactor in the condensation reaction process adopts a micro-channel reactor.
Example 31: this embodiment is the same as embodiment 1 except that: the reactor in the condensation reaction process adopts a kettle type reactor.
Example 32: this embodiment is the same as embodiment 1 except that: the reactor in the condensation reaction process adopts a loop reactor.
Example 33: this embodiment is the same as embodiment 1 except that: in the condensation reaction process, the reactor adopts a kettle type reactor and a tubular reactor which are connected in series.
TABLE 1 raw materials, parameters and results in examples 1-33
In conclusion, the method for producing α -acetyl-gamma-butyrolactone by the invention controls the reaction process by adjusting the flow rates of gamma-butyrolactone, acetate and liquid metal sodium, adopts a continuous production method, realizes sealing and automation, does not need to add benzene substances as a reaction solvent or an extractant, improves the reaction yield and ensures that the product quality is more stable.
The specific embodiments described herein are merely illustrative of the spirit of the invention and do not limit the scope of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.
Claims (10)
1. An apparatus for continuously producing α -acetyl-gamma-butyrolactone, comprising:
the condensation reactor is used for carrying out condensation reaction on materials;
a neutralization reactor for adjusting the pH value and converting the sodium salt obtained by condensation into α -acetyl-gamma-butyrolactone;
the phase separator is used for standing and separating an organic phase and a water phase;
an atmospheric distillation system for continuous distillation to remove light components from the organic phase;
a vacuum rectification system for continuous rectification,
the condensation reactor, the neutralization reactor, the phase separator, the atmospheric distillation system and the vacuum distillation system are communicated in sequence.
2. The continuous production apparatus of α -acetyl- γ -butyrolactone according to claim 1, wherein the condensation reactor comprises a microchannel reactor, a tank reactor, a loop reactor, a series of tank reactor and a tubular reactor.
3. The continuous production apparatus of α -acetyl-gamma-butyrolactone according to claim 1, wherein a power pump for providing kinetic energy for circulation is further disposed between the neutralization reactor and the phase separator.
4. A method for continuously producing α -acetyl- γ -butyrolactone according to claim 1, characterized in that it comprises the following steps:
(1) simultaneously and continuously adding gamma-butyrolactone, acetate and liquid metal sodium into a condensation reactor for condensation reaction;
(2) after the condensation reaction is finished, continuously transferring the condensation reaction liquid into a neutralization reactor, cooling, and adding phosphoric acid for neutralization;
(3) transferring the neutralized solution into a phase separator by a pump, standing for phase separation, removing a water phase, transferring an oil phase into a distillation system, and distilling under normal pressure and reduced pressure to obtain α -acetyl-gamma-butyrolactone.
5. The method for continuously producing α -acetyl-gamma-butyrolactone according to claim 4, wherein the molar mass ratio of gamma-butyrolactone to acetate is 1: 1.5-5.0.
6. The continuous production method of α -acetyl-gamma-butyrolactone according to claim 4 or 5, wherein the acetate is one or more of methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate and sec-butyl acetate.
7. The continuous production method of α -acetyl-gamma-butyrolactone according to claim 4, wherein the molar mass ratio of gamma-butyrolactone to liquid metal sodium is 1: 0.8-1.5.
8. The method for continuously producing α -acetyl-gamma-butyrolactone according to claim 4, wherein the condensation reaction temperature is 60-100 ℃.
9. The continuous process for the production of α -acetyl- γ -butyrolactone according to claim 4, wherein the residence time of the condensation reaction is 1-16 hours.
10. The method for continuously producing α -acetyl-gamma-butyrolactone according to claim 4, wherein the pressure of the condensation reaction is 0-2.0 MPa.
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