CN107915632B - Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate - Google Patents
Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate Download PDFInfo
- Publication number
- CN107915632B CN107915632B CN201711049359.8A CN201711049359A CN107915632B CN 107915632 B CN107915632 B CN 107915632B CN 201711049359 A CN201711049359 A CN 201711049359A CN 107915632 B CN107915632 B CN 107915632B
- Authority
- CN
- China
- Prior art keywords
- oxo
- chloro
- tower
- water
- ethyl butyrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/46—Preparation of carboxylic acid esters from ketenes or polyketenes
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C67/54—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/58—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/62—Use of additives, e.g. for stabilisation
Abstract
The invention belongs to the field of chemical industry, and particularly relates to a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate. The method comprises the following steps: the method comprises the steps of taking diketene, chlorine, dichloromethane and ethanol as raw materials, connecting HCl tail gas generated in the process of synthesizing 4-chloro-3-oxo-ethyl butyrate to a three-stage HCL absorption system, carrying out esterification reaction to obtain dichloromethane solution of the 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, washing the dichloromethane solution with water, removing a water phase from the three-stage HCL absorption system, feeding an organic phase into a light-ends removal rectifying tower, continuously feeding the organic phase into a negative pressure rectifying tower from a tower kettle through a metering pump to obtain a finished product of the 4-chloro-3-oxo-ethyl butyrate, and obtaining a byproduct 25-30% of industrial hydrochloric acid of the HCL absorption system, wherein the industrial hydrochloric acid can be used. The light component removal rectifying tower and the pressure reduction rectifying tower are adopted for continuously rectifying and separating the solvent and the product, the solvent can be recycled, the separation process is green and environment-friendly, and the rectifying efficiency is greatly improved.
Description
Technical Field
The invention belongs to the field of chemical industry, and particularly relates to a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate.
Background
4-chloro-3-oxo-butyric acid ethyl ester is a colorless pale yellow liquid, and the molecular weight: 164.59, melting point: -8 ℃, boiling point: 115 ℃ 14mmHg, density: 1.218, flash point: 96 ℃, water solubility: 47.5g/L (20 ℃ C.). 4-chloro-3-oxo-ethyl butyrate is a good medical synthetic intermediate, is mainly used for producing oxiracetam, belongs to medicaments for treating cerebrovascular diseases, is a 4 th generation of nootropic medicaments and derivatives of pyrrolidones, and has the trade names of Jianlangxing, orinnin, neuromet, neucan and the like. Oxiracetam is a novel central nervous system drug, and can promote the functional recovery of nerve cells and improve cerebral metabolism. The traditional Chinese medicine composition has multiple effects, has obvious curative effects on amnesia and senile dementia, has extremely low toxicity, is safe and reliable, has less adverse reaction, and thus has wide application range and wide market prospect.
The conventional production method of 4-chloro-3-oxo-ethyl butyrate which is mainly used in industrial production at present comprises the following steps: dissolving diketene in a solvent, cooling to-30 to-10 ℃, starting stirring, introducing a certain amount of chlorine into a reaction kettle at a certain flow rate, preserving heat at-30 to-10 ℃ for 1 to 2 hours, dripping a certain amount of ethanol into the reaction kettle after chlorination reaction, controlling the reaction temperature to be 0 to 5 ℃, heating to 20 to 25 ℃ after dripping, preserving heat for 1 hour, neutralizing the reaction product with alkali after esterification reaction, evaporating the solvent, and then carrying out reduced pressure distillation to obtain a colorless liquid product, namely 4-chloro-3-oxo-ethyl butyrate.
Chinese patent application publication No. CN103787883A reports a method for preparing gamma-chloroacetoacetic acid ethyl ester, which adopts a batch method to prepare, and adds a stabilizer in chlorination reaction to inhibit chlorination side reaction, but repeating the process and trying to achieve the effects described in the process cannot be achieved.
Chinese patent application publication No. CN106748764A reports a system and method for synthesizing ethyl γ -chloroacetoacetate, which mainly describes a micro-reactor system and a reaction process, and does not form a complete post-treatment process of the product, but only compares the content of the crude product after the reaction.
In journal of Liaoning chemical industry, 4-chloroacetoacetic acid ethyl ester adopts alkali liquor to wash reaction liquid, and waste salt is formed in water phase through neutralization, and the process brings a large amount of waste water and waste salt.
The existing 4-chloroacetoacetic acid methyl ester synthesis is an intermittent reaction, chlorine is greatly excessive in chlorination reaction, and the aqueous solution contains hypochlorous acid after tail gas absorption and cannot be sold as high-purity hydrochloric acid.
The prior art has the following defects: 1) the preparation process of the 4-chloro-3-oxo-ethyl butyrate is intermittent reaction, the reaction time is too long, the raw material feed ratio is not accurately controlled, and the chlorination byproducts are too much; 2) the post-treatment process is complex to operate, the process is discontinuous, the amount of waste water is large, waste salt is difficult to treat, the environmental pollution is serious, the product is difficult to separate, the rectification yield is low, and the product quality is poor.
Disclosure of Invention
In order to solve the above problems, the present invention aims to provide a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate, which solves the problems of large wastewater amount, difficult treatment of waste salt, serious environmental pollution, difficult product separation, low rectification yield, poor product quality, etc. in the existing synthesis process of 4-chloro-3-oxo-ethyl butyrate.
The technical scheme of the invention is as follows:
a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate is characterized by comprising the following steps:
1) using diketene, chlorine, dichloromethane and ethanol as raw materials, firstly dissolving chlorine in dichloromethane, and entering a micro-channel continuous flow reactor together with the diketene through a metering pumpThe chlorination reaction module and the ethanol enter the esterification reaction module to synthesize the 4-chloro-3-oxo-ethyl butyrate, HCl tail gas generated in the process is connected into a three-stage HCL absorption system, and the range of water absorption of each stage is m of water absorption of each stage1: diketene m2＝1.5～2：1；
2) Performing esterification to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, washing the dichloromethane solution with water, removing a water phase from a three-stage HCL absorption system, and allowing an organic phase to enter a light component removal rectifying tower;
3) preheating the organic phase to 30-40 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle to be 40-65 ℃, controlling the reflux ratio to be 1-5: 1, refluxing for 1-2 h, then separating water in a receiving tank at the top of the tower through a water separator, and collecting dichloromethane after the water content of the dichloromethane reaches 0.01-0.1% by mass percent;
4) after the organic phase is lightened, continuously feeding the organic phase into a negative pressure rectifying tower from a tower kettle through a metering pump, wherein the mass percentage content of 4-chloro-3-oxo-ethyl butyrate is 80-90%, adding a chloride ion adsorbent into the kettle liquid, then carrying out negative pressure rectification, controlling the vacuum degree to be 200 mmHg-300 mmHg, the kettle temperature to be 80-90 ℃, the reflux ratio to be 6-10: 1, refluxing for 1-2 h, and then, controlling the top temperature to be 65-75 ℃, and removing middle boiling components from the tower top;
5) after removing the intermediate boiling components, the mass percent of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 92-95%, the vacuum degree is further improved to be 0.1 mmHg-10 mmHg, the kettle temperature is controlled to be 110-130 ℃, the reflux ratio is 10-20: 1, after refluxing for 1-2 h, the top temperature is 105-115 ℃, the top temperature is rectified at the top of the tower to collect the finished product of 4-chloro-3-oxo-ethyl butyrate, and the byproduct of the HCL absorption system, namely the industrial hydrochloric acid with the mass percent of 25-30%, can be used for sale.
And further, the washing quantity of the water washing layering tower is the same as the water absorption quantity of the three-stage HCL, and the water washing analysis is carried out until the PH range of the organic phase is 7-8.
Further, water separated in the receiving tank at the top of the tower through a water separator in the step 3) enters an HCL absorption system.
Further, the temperature at the top of the tower is controlled to be 40-50 ℃ in the step 3), and dichloromethane is extracted for use.
Further, the chloride ion resistant adsorbent added in the step 4) is SiO2、Al2O3And ZSM-5 molecular sieve, the addition of the adsorbent is 100 mg-300 mg per kg of crude product.
Further, the residue in step 5) is subjected to external treatment or incineration.
Further, the yield of the finished product of the 4-chloro-3-oxo-ethyl butyrate from the reaction to the rectification in the step 5) is 90-93%, and the content of the 4-chloro-3-oxo-ethyl butyrate product is 98% -99%.
Furthermore, the theoretical plate number of the light component removal rectifying tower and the vacuum rectifying tower is 50-100, and stainless steel corrugated fillers are filled in the towers.
The invention relates to a post-treatment process for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate,
1) the method comprises the following steps of taking diketene, chlorine, dichloromethane and ethanol as raw materials, firstly dissolving chlorine in dichloromethane, feeding the solution and the diketene into a chlorination reaction module of a micro-channel continuous flow reactor through a metering pump, feeding the solution and the ethanol into an esterification reaction module to synthesize 4-chloro-3-oxo-ethyl butyrate, and feeding HCl tail gas generated in the process into a three-stage HCL absorption system, wherein the range of water absorption of each stage is m (the water absorption of each stage): m (diketene) is 1.5-2: 1;
2) performing esterification reaction to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, wherein the washing amount of the water washing layering tower is the same as the absorption water amount of the three-stage HCL, performing water washing analysis until the PH range of an organic phase is 7-8, removing a water phase from a three-stage HCL absorption system after water washing, and feeding the organic phase into a light component removal rectifying tower;
3) preheating the organic phase to 30-40 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle to be 40-65 ℃, controlling the reflux ratio to be 1-5: 1, refluxing for 1-2 h, then separating water in a tower top receiving tank through a water separator (the separated water enters an HCL absorption system), controlling the temperature of the tower top to be 40-50 ℃ after the water content of dichloromethane reaches 0.01-0.1%, and collecting dichloromethane (the rectified dichloromethane can be used for reaction).
4) After the organic phase is subjected to lightness removing, the organic phase continuously enters a negative pressure rectifying tower from a tower kettle through a metering pump, the content of 4-chloro-3-oxo-ethyl butyrate is 80-90%, and because the organic phase contains higher chloride ions, in order to prevent deep chlorination of the 4-chloro-3-oxo-ethyl butyrate at high temperature and further influence the product yield, a chloride ion adsorbent is added into the kettle solution, and the added chloride ion adsorbent is SiO2、Al2O3And a ZSM-5 molecular sieve, wherein the addition amount of an adsorbent is 100 mg-300 mg per kg of crude product, then negative pressure rectification is carried out, the vacuum degree is 200 mmHg-300 mmHg, the kettle temperature is controlled to be 80-90 ℃, the reflux ratio is controlled to be 6-10: 1, the top temperature is 65-75 ℃ after reflux is carried out for 1-2 h, and middle boiling components are removed from the top of the tower;
5) after removing the intermediate boiling components, the content of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 92-95%, the vacuum degree is further improved to be 0.1-10 mmHg, the kettle temperature is controlled to be 110-130 ℃, the reflux ratio is 10-20: 1, after refluxing for 1-2 h, the top temperature is 105-115 ℃, the top temperature is rectified at the top of the tower to collect the finished product of the 4-chloro-3-oxo-ethyl butyrate, the kettle residue is subjected to external treatment (or incineration), the yield from reaction to rectification is 90-93%, the product content is 98-99%, and the byproduct of an HCL absorption system is 25-30% of industrial hydrochloric acid for sale.
The theoretical plate number of the light component removal rectifying tower and the vacuum rectifying tower is 50-100, and stainless steel corrugated packing is filled in the towers.
Advantageous effects
The post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate provided by the invention has the following beneficial effects:
1) 4-chloro-3-oxo-ethyl butyrate is synthesized by a micro-channel continuous flow method, so that the yield and quality of the product are improved compared with those of a batch method;
2) the tail gas adopts a three-stage HCL absorption system, and the water phase after washing can be merged into the tail gas, the HCL absorption system produces a byproduct of 25-30% of industrial hydrochloric acid for sale, so that the problems of large waste water amount and difficulty in waste salt treatment are solved;
3) the light component removal rectifying tower and the pressure reduction rectifying tower are adopted for continuously rectifying and separating the solvent and the product, the solvent can be recycled, the separation process is green and environment-friendly, and the rectifying efficiency is greatly improved;
4) when the product is rectified, the chloride ion adsorbent is adopted, so that the deep chlorination of the product in the rectification process can be inhibited, and the quality of the 4-chloro-3-oxo-ethyl butyrate product can be ensured.
Drawings
FIG. 1 is a process flow diagram of a post-treatment method for continuous synthesis of ethyl 4-chloro-3-oxo-butyrate.
Detailed Description
The present invention is further illustrated below with reference to examples, which are understood by those skilled in the art to be illustrative only and not to constitute any limitation to the present invention.
Example 1: a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate comprises the following steps:
1) the method comprises the following steps of taking diketene, chlorine, dichloromethane and ethanol as raw materials, firstly dissolving chlorine in dichloromethane, feeding the solution and the diketene into a chlorination reaction module of a micro-channel continuous flow reactor through a metering pump, feeding the solution and the ethanol into an esterification reaction module to synthesize 4-chloro-3-oxo-ethyl butyrate, and feeding HCl tail gas generated in the process into a three-stage HCL absorption system, wherein the range of water absorption of each stage is m (the water absorption of each stage): m (diketene) ═ 1.5: 1;
2) performing esterification reaction to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, wherein the washing amount of the water washing layering tower is the same as the absorption water amount of the three-stage HCL, performing water washing analysis until the PH range of an organic phase is 7, performing water washing, then removing a water phase from a three-stage HCL absorption system, and enabling the organic phase to enter a light component removal rectifying tower;
3) preheating the organic phase to 30 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle at 40 ℃, controlling the reflux ratio range at 1:1, refluxing for 1h, then separating water in a receiving tank at the top of the tower through a water separator (the separated water enters an HCL absorption system), and after the water content of dichloromethane reaches 0.01%, controlling the temperature at the top of the tower at 40 ℃ to collect dichloromethane (the rectified dichloromethane can be used as a reaction part).
4) After the organic phase is lightness removed, the organic phase continuously enters a negative pressure rectifying tower from a tower kettle through a metering pump, and at the moment, the 4-chloro-3-oxo-ethyl butyrateThe ester content is 80%, and because the organic phase contains higher chloride ions, in order to prevent 4-chloro-3-oxo-ethyl butyrate from deep chlorination at high temperature and further influence the product yield, a chloride ion adsorbent is added into the kettle liquid, and the added chloride ion adsorbent is SiO2、Al2O3And a ZSM-5 molecular sieve, wherein the addition amount of an adsorbent is 100 mg/kg of crude product, then negative pressure rectification is carried out, the vacuum degree is 200mmHg, the kettle temperature is controlled to be 80 ℃, the reflux ratio is controlled to be 6:1, the top temperature is 65 ℃ after reflux is carried out for 1h, and middle boiling components are removed from the top of the tower;
5) after removing the intermediate boiling components, the content of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 92 percent, the vacuum degree is further improved to be 0.1mmHg, the kettle temperature is controlled at 110 ℃, the reflux ratio is 10:1, after refluxing for 1h, the top temperature is 105 ℃, the finished product of the 4-chloro-3-oxo-ethyl butyrate is rectified and collected at the top of the tower, the kettle residue is subjected to external treatment (or incineration), the yield of the rectified finished product is 90 percent from the reaction, the product content is 98 percent, and the byproduct of 25 percent of industrial hydrochloric acid of the HCL absorption system is used for sale.
The theoretical plate of the light component removal rectifying tower and the vacuum rectifying tower is 50, and the filling materials in the towers are stainless steel corrugated filling materials.
Example 2: a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate comprises the following steps:
1) step 1) is the same as in example 1, and the range of the absorbed water amount per stage is m (the absorbed water amount per stage): m (diketene) ═ 1.8: 1;
2) performing esterification to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, wherein the washing amount of the water washing layering tower is the same as the absorption water amount of the three-stage HCL, performing water washing analysis until the PH range of an organic phase is 7.5, removing a water phase from a three-stage HCL absorption system after washing, and feeding the organic phase into a light component removal rectifying tower;
3) preheating the organic phase to 35 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle to be 55 ℃, controlling the reflux ratio range to be 3:1, refluxing for 1.5h, then separating water in a tower top receiving tank through a water separator (the separated water enters an HCL absorption system), and after the water content of dichloromethane reaches 0.05%, controlling the temperature of the tower top to be 45 ℃ to extract dichloromethane (the rectified dichloromethane can be used as a reaction part).
4) After the organic phase is lightness removed, the organic phase continuously enters a negative pressure rectifying tower from a tower kettle through a metering pump, the content of 4-chloro-3-oxo-ethyl butyrate is 85 percent, and because the organic phase contains higher chloride ions, in order to prevent the 4-chloro-3-oxo-ethyl butyrate from being deeply chlorinated at high temperature and further influence the product yield, a chloride ion adsorbent is added into the kettle solution, and the added chloride ion adsorbent is SiO2、Al2O3And a ZSM-5 molecular sieve, wherein the addition amount of an adsorbent is 200 mg/kg of crude product, then negative pressure rectification is carried out, the vacuum degree is 250mmHg, the kettle temperature is controlled to be 85 ℃, the reflux ratio is controlled to be 8:1, the top temperature is 70 ℃ after reflux is carried out for 1.5h, and middle boiling components are removed from the top of the tower;
5) after removing the intermediate boiling components, the content of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 93%, the vacuum degree is further improved to 8mmHg, the kettle temperature is controlled at 115 ℃, the reflux ratio is 15:1, after refluxing for 1.5h, the top temperature is 110 ℃, the finished product of 4-chloro-3-oxo-ethyl butyrate is rectified and collected at the top of the tower, the kettle residue is subjected to external treatment (or incineration), the yield of the finished product of rectification from the reaction to the reaction is 91.9%, the product content is 98.2%, and 28% of industrial hydrochloric acid is a byproduct of an HCL absorption system and is used for sale.
The theoretical plate of the light component removing rectifying tower and the vacuum rectifying tower is 80, and the filling materials in the towers are stainless steel corrugated filling materials
Example 3: a post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate comprises the following steps:
1) step 1) is the same as in example 1, and the range of the absorbed water amount per stage is m (the absorbed water amount per stage): m (diketene) ═ 2: 1;
2) performing esterification reaction to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, wherein the washing amount of the water washing layering tower is the same as the absorption water amount of the three-stage HCL, performing water washing analysis until the PH range of an organic phase is 8, performing water washing, then removing a water phase from a three-stage HCL absorption system, and enabling the organic phase to enter a light component removal rectifying tower;
3) preheating the organic phase to 40 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle to be 65 ℃, controlling the reflux ratio range to be 5:1, refluxing for 2 hours, then separating water in a receiving tank at the top of the tower through a water separator (the separated water enters an HCL absorption system), and controlling the temperature at the top of the tower to be 50 ℃ to extract dichloromethane (the rectified dichloromethane can be used as a reaction part) when the water content of the dichloromethane reaches 0.1%.
4) After the organic phase is lightened, the organic phase continuously enters a negative pressure rectifying tower from a tower kettle through a metering pump, the content of 4-chloro-3-oxo-ethyl butyrate is 90 percent, and because the organic phase contains higher chloride ions, in order to prevent the 4-chloro-3-oxo-ethyl butyrate from being deeply chlorinated at high temperature and further influence the product yield, a chloride ion adsorbent is added into the kettle solution, and the added chloride ion adsorbent is SiO2、Al2O3And a ZSM-5 molecular sieve, wherein the addition amount of an adsorbent is 300 mg/kg of crude product, then negative pressure rectification is carried out, the vacuum degree is 300mmHg, the kettle temperature is controlled to be 90 ℃, the reflux ratio is controlled to be 10:1, the top temperature is 75 ℃ after reflux is carried out for 2 hours, and middle boiling components are removed from the top of the tower;
5) after removing the intermediate boiling components, the content of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 95%, the vacuum degree is further improved to 10mmHg, the kettle temperature is controlled at 130 ℃, the reflux ratio is 20:1, after refluxing for 2h, the top temperature is 115 ℃, the finished product of 4-chloro-3-oxo-ethyl butyrate is rectified and collected at the top of the tower, the kettle residue is subjected to external treatment (or incineration), the yield of the finished product is 93% from reaction to rectification, the product content is 99.0%, and 30% of industrial hydrochloric acid is a byproduct of an HCL absorption system and is used for sale.
The theoretical plate of the light component removal rectifying tower and the vacuum rectifying tower is 100, and the fillers in the towers are stainless steel corrugated fillers.
Claims (5)
1. A post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate is characterized by comprising the following steps:
1) using diketene, chlorine, dichloromethane and ethanol as raw materials, firstly dissolving chlorine in dichloromethane, entering a chlorination reaction module of a micro-channel continuous flow reactor together with the diketene through a metering pump, then entering an esterification reaction module with the ethanol to synthesize 4-chloro-3-oxo-ethyl butyrate, wherein HCl tail gas generated in the process is connected into a three-stage HCL absorption system, and the range of water absorption of each stage is m of water absorption of each stage1: diketene m2＝1.5～2：1；
2) Performing esterification to obtain a dichloromethane solution of 4-chloro-3-oxo-ethyl butyrate, adding the dichloromethane solution into a water washing layering tower, washing the dichloromethane solution with water, removing a water phase from a three-stage HCL absorption system, and allowing an organic phase to enter a light component removal rectifying tower; the washing quantity of the washing layering tower is the same as the absorption water quantity of the third-stage HCL, and the washing analysis is carried out until the PH range of the organic phase is 7-8;
3) preheating the organic phase to 30-40 ℃ through a preheater, continuously feeding the organic phase from a light component removal rectifying tower, controlling the temperature of a tower kettle to be 40-65 ℃, controlling the reflux ratio to be 1-5: 1, refluxing for 1-2 h, then separating water in a receiving tank at the top of the tower through a water separator, and collecting dichloromethane after the water content of the dichloromethane reaches 0.01-0.1% by mass percent; water separated by a water separator in a tower top receiving tank enters an HCL absorption system;
4) after the organic phase is lightened, continuously feeding the organic phase into a reduced pressure rectification tower from a tower kettle through a metering pump, wherein the mass percentage content of 4-chloro-3-oxo-ethyl butyrate is 80-90%, adding a chloride ion adsorbent into the kettle liquid, then carrying out negative pressure rectification, controlling the vacuum degree to be 200 mmHg-300 mmHg, the kettle temperature to be 80-90 ℃, the reflux ratio to be 6-10: 1, refluxing for 1-2 h, and then, controlling the top temperature to be 65-75 ℃, and removing middle boiling components from the tower top; the added chloride ion adsorbent is SiO2、Al2O3And ZSM-5 molecular sieve, the addition of the adsorbent is 100 mg-300 mg per kg of crude product;
5) after removing the intermediate boiling components, the mass percent of 4-chloro-3-oxo-ethyl butyrate in the kettle liquid is 92-95%, the vacuum degree is further improved to be 0.1 mmHg-10 mmHg, the kettle temperature is controlled to be 110-130 ℃, the reflux ratio is 10-20: 1, after refluxing for 1-2 h, the top temperature is 105-115 ℃, the top temperature is rectified at the top of the tower to collect the finished product of 4-chloro-3-oxo-ethyl butyrate, and the byproduct of the HCL absorption system, namely the industrial hydrochloric acid with the mass percent of 25-30%, can be used for sale.
2. The post-treatment method for continuously synthesizing ethyl 4-chloro-3-oxo-butyrate according to claim 1, wherein the temperature at the top of the tower in the step 3) is controlled to be 40-50 ℃ to extract a reaction part which can be used for recycling dichloromethane.
3. The process of claim 1, wherein step 5) is carried out by ex situ treatment or incineration of the residue.
4. The post-treatment method for continuously synthesizing ethyl 4-chloro-3-oxo-butyrate according to claim 1, wherein the yield of the finished product of ethyl 4-chloro-3-oxo-butyrate from the reaction to the rectification in the step 5) is 90-93%, and the content of the ethyl 4-chloro-3-oxo-butyrate is 98% -99%.
5. The post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate according to claim 1, wherein the theoretical plates of the light component removal rectifying tower and the vacuum rectifying tower are 50-100, and stainless steel corrugated fillers are filled in the towers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711049359.8A CN107915632B (en) | 2017-10-31 | 2017-10-31 | Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711049359.8A CN107915632B (en) | 2017-10-31 | 2017-10-31 | Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107915632A CN107915632A (en) | 2018-04-17 |
| CN107915632B true CN107915632B (en) | 2020-11-13 |
Family
ID=61895913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711049359.8A Active CN107915632B (en) | 2017-10-31 | 2017-10-31 | Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107915632B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112500290B (en) * | 2020-12-02 | 2021-07-30 | 江苏恒安化工有限公司 | Method for synthesizing 4-chloroacetoacetic acid methyl ester or 4-chloroacetoacetic acid ethyl ester |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4468356A (en) * | 1981-04-15 | 1984-08-28 | Eastman Kodak Company | Diketene chlorination method |
| CN105693509A (en) * | 2016-03-25 | 2016-06-22 | 上海应用技术学院 | Method for continuously synthesizing ethyl 4-chloroacetoacetates |
| CN106748764A (en) * | 2017-03-15 | 2017-05-31 | 江苏诚信药业有限公司 | The continuous synthesis system and method for a kind of 4 chloroacetyl acetacetic ester |
-
2017
- 2017-10-31 CN CN201711049359.8A patent/CN107915632B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4468356A (en) * | 1981-04-15 | 1984-08-28 | Eastman Kodak Company | Diketene chlorination method |
| CN105693509A (en) * | 2016-03-25 | 2016-06-22 | 上海应用技术学院 | Method for continuously synthesizing ethyl 4-chloroacetoacetates |
| CN106748764A (en) * | 2017-03-15 | 2017-05-31 | 江苏诚信药业有限公司 | The continuous synthesis system and method for a kind of 4 chloroacetyl acetacetic ester |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107915632A (en) | 2018-04-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107915631B (en) | Post-treatment method for continuously synthesizing 4-chloroacetoacetic acid methyl ester | |
| CN102503014B (en) | Treatment method of glycerin wastewater containing salt | |
| CN103130197B (en) | Continuous-pressure-changing rectification method and device for preparing medicine-level sulfoxide chloride | |
| CN106220532B (en) | A kind of method of separation of extractive distillation acetonitrile and triethylamine | |
| CN103880690B (en) | A kind of environment friendly clean producing method of glycine | |
| CN113429313B (en) | Preparation method of acetone oxime methyl ether | |
| CN102617542B (en) | Method for preparing and purifying olmesartan intermediate | |
| CN102633686A (en) | Preparation method of peramivir | |
| CN103113257B (en) | Continuous reactive distillation equipment for synthesising methoxylamine hydrochloride and process thereof | |
| CN109096116A (en) | A method of nitro-chlorobenzene is prepared using vacuum concentration process | |
| CN107915632B (en) | Post-treatment method for continuously synthesizing 4-chloro-3-oxo-ethyl butyrate | |
| CN111269131A (en) | Process for preparing cyclopropyl ethyl amide by taking tri-n-propylamine as acid acceptor | |
| CN113072434B (en) | Method for preparing cyclopropyl methyl ketone by one-step method | |
| CN108069821A (en) | A kind of difluoroethanol synthesis technology | |
| CN101508678B (en) | Process for preparing 2-methyl-4-amino-5-acetyl aminomethyl pyrimidine | |
| CN216303678U (en) | Recovery processing device for waste liquid generated in acetochlor production | |
| CN103641793B (en) | Treatment method of AE (Active Ester) residual liquid | |
| CN105330545A (en) | Method for recycling oxalic acid from triazine ring cyclization mother liquor dreg with tin chloride as catalyst | |
| CN114409612B (en) | Preparation method of high-content 2-chloro-5-chloromethylthiazole | |
| CN103848768B (en) | The application method of a kind of Methylaminoformyl chloride decomposed tail gas hydrogenchloride in cartap synthesis | |
| CN113549027B (en) | Continuous production process of 2-chloro-5-chloromethylthiazole | |
| CN107445927A (en) | The technique that a kind of xylose dehydration prepares furfural | |
| CN112479853A (en) | Preparation method of D-2-chloropropionyl chloride and D-2-chloropropionyl chloride | |
| CN115845421B (en) | System and method for continuously separating perfluorinated hexanone | |
| CN212067785U (en) | Dividing wall tower for refining 1, 3-dioxolane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |