Device and method for purifying methyl 4-chloroacetoacetate

Abstract

The invention discloses a methyl 4-chloroacetoacetate purification device which comprises a heating base and a controller, the controller is fixedly installed on the front side of the heating base, the heating base is electrically connected with the controller, and a distillation mechanism is fixedly installed on the top of the heating base and electrically connected with the controller; the exhaust mechanism is arranged on the rear side of the distillation mechanism and is electrically connected with the controller; the heat circulation mechanism is arranged on the right side of the heating base and electrically connected with the controller. According to the purification device and purification method for methyl 4-chloroacetoacetate, the extraction and storage efficiency is high, the speed is high, a user does not need to worry about advanced gasification of high-boiling-point components, meanwhile, other components can be prevented from being mixed with methyl 4-chloroacetoacetate again after distillation, the purification effect is effectively improved, and waste heat of condensate water can be recycled.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical equipment, in particular to a purification device and a purification method for methyl 4-chloroacetoacetate. Background Art

[0002] Methyl 4-chloroacetoacetate is a chemical substance ranging from a transparent, colorless liquid to a pale yellow liquid. It is an organic synthesis intermediate and a pharmaceutical raw material intermediate. The main conventional production method of methyl 4-chloroacetoacetate in industrial production is a batch process. First, diketene is dissolved in a solvent, then cooled and stirred. A certain amount of chlorine gas is introduced into a reactor at a certain flow rate. After the chlorination reaction is completed, a certain amount of methanol is added dropwise. After the esterification reaction is completed, the product is neutralized with alkali, the solvent is evaporated, and then vacuum distillation is performed to obtain a colorless liquid product, namely methyl 4-chloroacetoacetate. The obtained product is impure. Common impurities in methyl 4-chloroacetoacetate include methyl acetoacetate, methyl 2-chloroacetoacetate, and water. The quality test for methyl 4-chloroacetoacetate requires that the mass fraction of methyl 4-chloroacetoacetate be greater than 98%, the mass fraction of methyl acetoacetate be less than 0.3%, the mass fraction of methyl 2-chloroacetoacetate be less than 0.2%, and the mass fraction of water be less than 0.1%. The boiling point of methyl 4-chloroacetoacetate is approximately 212 degrees Celsius, while the boiling points of other impurities are all below 200 degrees Celsius, satisfying the requirements of being mutually soluble, liquid, and having a boiling point difference greater than 30 degrees Celsius. Distillation is often used for purification. Existing purification devices heat the mixed liquid by steam and control the temperature during heating to keep the temperature of the mixed liquid higher than the boiling point of the low-boiling-point component and lower than the boiling point of the high-boiling-point chemical reagent. The low-boiling-point chemical reagent evaporates into gas and then is condensed through a condenser for separation. In the heating process, in order to prevent the local temperature from being too high, which will cause the high-boiling-point component to vaporize, a slow heating method is usually adopted, and the separation rate is slow. In addition, after the low-boiling-point component is completely evaporated, a certain component still exists in the distillation kettle in the form of gas and cannot be completely discharged. This part will merge with the finished product, resulting in insufficient separation. In addition, the distillation process continues to heat during the condensation process, and the condensation process continues to dissipate heat, resulting in large energy loss. Summary of the Invention

[0003] The object of the present invention is to provide a purification device and a purification method to at least solve the problems of the prior art such as slow separation rate, inability to completely separate the components, and large heat loss.

[0004] To achieve the above object, the present invention provides the following technical solution: a purification device for methyl chloroacetoacetate, comprising: a heating base and a controller, wherein the controller is fixedly mounted on the front side of the heating base and electrically connected to the heating base, and further comprising: a distillation mechanism fixedly mounted on the top of the heating base and electrically connected to the controller; an exhaust mechanism disposed on the rear side of the distillation mechanism and electrically connected to the controller; and a thermal circulation mechanism disposed on the right side of the heating base and electrically connected to the controller. The purpose is that the distillation mechanism includes: a distillation kettle, fixedly installed on the top of the heating base; a vertical tube, arranged at the top of the distillation kettle; an inclined tube, arranged on the left side of the vertical tube; a bent tube, arranged on the right side of the vertical tube; two condensation components, respectively arranged on the left side of the inclined tube and the right side of the bent tube; several arc-shaped heat conduction plates, circumferentially arranged at the bottom of the inner cavity of the distillation kettle; a first temperature detector, arranged at the top of the inner cavity of the vertical tube, and at the same height as the inclined tube and the bent tube, and electrically connected to the controller; a loading and unloading component, arranged at the bottom of the distillation kettle, and electrically connected to the controller.

[0005] Preferably, the purpose is that the condensation component includes: a condenser, the two condenser tubes of the condensation component are respectively arranged on the left side of the inclined tube and the right side of the bent tube, and the two condenser tubes are both inclined and gradually inclined downward from the inner end to the outer end; a lower port is arranged at the outer end of the condenser tube; an upper port is arranged at the inner end of the condenser tube; a first solenoid valve is arranged at the outer end of the condenser tube and is electrically connected to the controller; a conduit is arranged on the outside of the first solenoid valve; and a collection box is arranged at the bottom end of the conduit.

[0006] Preferably, the purpose is that the loading and unloading components include: a feed pipe, which is arranged at the bottom of the distillation kettle and extends to the bottom of the heating base; a reversing valve, which is arranged at the bottom end of the feed pipe and is electrically connected to the controller; a feed pipe, which is installed on the left side of the bottom of the reversing valve; and a discharge pipe, which is installed on the right side of the bottom of the reversing valve.

[0007] Preferably, the purpose is that the exhaust mechanism includes: an exhaust pipe, which is arranged on the rear side of the inner cavity of the distillation kettle, and the exhaust pipe extends to the rear side of the distillation kettle; a second temperature detector, which is arranged on the outer wall of the exhaust pipe and electrically connected to the controller; a heater, which is arranged on the rear side of the exhaust pipe and electrically connected to the controller; a heat-conducting mesh plate, which is arranged on the side wall of the inner cavity of the heater; a second solenoid valve, which is arranged at the rear end of the heater and electrically connected to the controller; a connecting pipe, which is arranged on the rear side of the second solenoid valve, and the middle part of the connecting pipe is vertically arranged; a heat exchange box, which is sleeved on the middle part of the connecting pipe; and a gas storage tank, which is installed at the rear end of the connecting pipe.

[0008] Preferably, the purpose is that the heat circulation mechanism includes: a water tank, which is arranged on the right side of the heating base; a water pump, which is installed at the rear bottom of the water tank and is electrically connected to the controller; a cold water pipe, one end of which is arranged at the water outlet end of the water pump, and the other end of the cold water pipe is respectively connected to the lower ports of the two condensing components; two hot water pipes, one end of which is respectively connected to the upper ports of the two condensing components, and the other end is connected to the bottom of the heat exchange box; a return pipe, one end of which is arranged at the top of the heat exchange box, and the other end is connected to the water tank.

[0009] A purification method for a purification device of methyl chloroacetoacetate, comprising the following steps: Step 1: The controller controls the reversing valve to connect the delivery pipe with the feed pipe, and the mixed liquid flows from the feed pipe into the inner cavity of the distillation kettle. The controller controls the reversing valve to close, completing the loading; In step 2, the controller controls the heating base to heat the distillation kettle. As the temperature continues to rise, the components with lower boiling points in the mixed liquid evaporate and gasify. The first thermometer detects the temperature of the steam. The controller controls the first solenoid valve on the right to open, and the steam rises and enters the bent pipe. During the rising section of the bent pipe, the high-boiling-point components in the steam are pre-cooled and liquefied. After liquefaction, they flow back to the inner cavity of the distillation kettle along the bent pipe. The high-boiling-point components release heat during the liquefaction process, so that the low-boiling-point components maintain a vaporized state and enter the condensation component through the bent pipe, thereby completing the recovery of the high-boiling-point components. Step 3: The controller controls the water pump to inject the low-temperature condensed water in the water tank cavity into the condenser from the lower port through the cold water pipe. After the condenser cavity is full of condensed water, it flows out from the upper port. The high-temperature steam flows from top to bottom in the condenser, and the low-temperature condensed water flows from bottom to top to perform heat exchange. The temperature of the condensed water rises after passing through the condenser, and the high-temperature steam is pre-cooled and liquefied, and then enters the collection box through the conduit on the right; Step 4: As the low-boiling-point components in the mixed liquid are evaporated, the temperature in the inner cavity of the still pot gradually increases. When the first thermometer detects that the temperature has reached the set temperature, the controller controls the second solenoid valve to open. The inert gas in the gas storage tank is heated to the set temperature by the heater and then injected into the bottom of the inner cavity of the still pot from the exhaust pipe. The second thermometer measures the temperature of the inert gas to ensure that the inert gas is at the specified temperature. With the injection of the high-temperature inert gas, the vapor of the residual low-boiling-point components in the inner cavity of the still pot is completely discharged from the bent pipe. Then the first and second solenoid valves on the right are closed, completing the separation of the low-boiling-point components. Step 5: The controller controls the temperature in the inner cavity of the still to continue to rise, and the first solenoid valve on the left is opened. The 4-chloroacetoacetate vapor enters the condensation assembly on the left through the inclined pipe, and the condensed liquid 4-chloroacetoacetate flows into the collection box on the left through the left conduit; In step six, the high-temperature condensed water passing through the condenser is injected into the heat exchange box through the hot water pipe, and the inert gas in the connecting pipe is preheated, which reduces the energy consumption required to heat the inert gas to the set temperature. The condensed water then flows back to the water tank through the return pipe.

[0010] The beneficial effects of the present invention compared with the prior art are: The heating base of the present invention heats the distillation kettle, and the components with lower boiling points in the mixed liquid evaporate and gasify. The controller controls the first solenoid valve located on the right to open, and the steam rises and enters the bent tube. During the rising section of the bent tube, the high-boiling-point components in the steam are pre-cooled and liquefied. After liquefaction, they flow back to the inner cavity of the distillation kettle along the bent tube. The high-boiling-point components release heat during the liquefaction process, so that the low-boiling-point components maintain a gasified state and enter the condensation component through the bent tube. Therefore, the extraction and storage efficiency is high and the speed is fast. There is no need to worry about the high-boiling-point components being vaporized in advance, and the purification effect is good.

[0011] The present invention controls the opening of the second solenoid valve, and after the inert gas in the gas storage tank is heated to a set temperature by a heater, it is injected into the bottom of the inner cavity of the distillation kettle through the exhaust pipe. The second temperature detector measures the temperature of the inert gas, thereby ensuring that the inert gas is at a specified temperature. With the injection of the high-temperature inert gas, the steam of the low-boiling point components remaining in the inner cavity of the distillation kettle is completely discharged from the bent pipe, ensuring that other steam components can be completely discharged, avoiding re-mixing with methyl 4-chloroacetoacetate, and effectively improving the purification effect.

[0012] 3. The present invention uses a water pump to inject the low-temperature condensed water in the inner cavity of the water tank into the condenser from the lower port through the cold water pipe. After the water in the inner cavity of the condenser is full, it flows out from the upper port. The high-temperature steam flows from top to bottom in the condenser, and the low-temperature condensed water flows from bottom to top to perform heat exchange. The temperature of the condensed water rises after passing through the condenser. The high-temperature condensed water passing through the condenser is injected into the heat exchange box through the hot water pipe, and the inert gas in the connecting pipe is preheated, thereby reducing the energy consumption required to heat the inert gas to the set temperature. The condensed water then flows back to the water tank through the return pipe, thereby recycling the waste heat of the condensed water. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 This is the main view of the present invention; Figure 3 This is a front cross-sectional view of the present invention; Figure 4 for Figure 3 A magnified view of point A in the figure; Figure 5 It is a right side cross-sectional view of the distillation mechanism; Figure 6 for Figure 5 Enlarged view of point B in FIG. Figure 7 It is a rear cross-sectional view of the present invention; Figure 8 for Figure 7 Enlarged view of point C in the figure.

[0014] In the figure: 2. Heating base; 3. Distillation mechanism; 31. Distillation kettle; 32. Vertical tube; 33. Inclined tube; 34. Bent tube; 35. Condensation assembly; 351. Condensation tube; 352. Lower port; 353. Upper port; 354. First solenoid valve; 355. Conduit; 356. Collection box; 36. Arc-shaped heat conduction plate; 37. First temperature detector; 38. Loading and unloading assembly; 381. Feed pipe; 382. Reversing valve; 383. Feed pipe; 384. Discharge pipe; 4. Exhaust mechanism; 41. Exhaust pipe; 42. Second temperature detector; 43. Heater; 44. Heat conduction mesh plate; 45. Second solenoid valve; 46. Connecting pipe; 47. Heat exchange box; 48. Gas storage tank; 5. Thermal circulation mechanism; 51. Water tank; 52. Water pump; 53. Cold water pipe; 54. Hot water pipe; 55. Reflux pipe; 6. Controller. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] See also Figures 1-8 The present invention provides a purification device and a purification method for methyl 4-chloroacetoacetate, comprising a heating base 2 and a controller 6. The controller 6 is fixedly mounted on the front side of the heating base 2 and is electrically connected to the heating base 2. The controller 6 is modularly assembled from an internal CPU, instruction and data storage, input and output units, a power module, a digital analog unit, and other units. Instructions for performing operations such as logical operations, sequential control, timing, counting, and arithmetic operations are stored internally, and various types of mechanical equipment or production processes are controlled through digital or analog input and output. The device also includes: a distillation mechanism 3 fixedly mounted on the top of the heating base 2 and electrically connected to the controller 6; an exhaust mechanism 4 is disposed on the rear side of the distillation mechanism 3 and electrically connected to the controller 6; and a thermal circulation mechanism 5 is disposed on the right side of the heating base 2 and electrically connected to the controller 6.

[0017] The distillation mechanism 3 is heated by the heating base 2, and the mixed liquid in the distillation mechanism 3 evaporates and condenses in sequence from low to high boiling points. The exhaust mechanism 4 is used to empty the steam in the distillation mechanism 3, and the heat circulation mechanism 5 is used to preheat and recycle the distillation mechanism 3.

[0018] The distillation mechanism 3 includes: a distillation kettle 31, a vertical tube 32, an inclined tube 33, a bent tube 34, a condensation component 35, an arc-shaped heat conducting plate 36, a first temperature detector 37 and a loading and unloading component 38. The distillation kettle 31 is fixedly installed on the top of the heating base 2, the vertical tube 32 is arranged on the top of the distillation kettle 31, the inclined tube 33 is arranged on the left side of the vertical tube 32, and the bent tube 34 is arranged on the right side of the vertical tube 32. The bent tube 34 is divided into an ascending section and a descending section. The steam rises and enters the bent tube 34. During the ascending section of the bent tube 34, the high-boiling-point component in the steam is pre-cooled and liquefied. After liquefaction, it flows back to the inner cavity of the distillation kettle 31 along the bent tube 34. The high-boiling-point component releases heat during the liquefaction process, which makes the low-boiling-point component The vaporized state is maintained through the bent tube 34. There are two condensation components 35, which are respectively arranged on the left side of the inclined tube 33 and the right side of the bent tube 34. There are several arc-shaped heat conducting plates 36, which are circumferentially arranged at the bottom of the inner cavity of the distillation kettle 31. The arc-shaped heat conducting plates 36 are used to uniformly heat the mixed liquid to prevent boiling caused by uneven heating. The first thermometer 37 is arranged at the top of the inner cavity of the vertical tube 32 and is at the same height as the inclined tube 33 and the bent tube 34, so that the temperature of the steam discharged into the inclined tube 33 or the bent tube 34 can be controlled, thereby controlling the components in the steam, and is electrically connected to the controller 6. The loading and unloading components 38 are arranged at the bottom of the distillation kettle 31 and are electrically connected to the controller 6.

[0019] As a preferred solution, further, Figure 2-4 As shown, the condensation assembly 35 includes: a condensation pipe 351, a lower port 352, an upper port 353, a first solenoid valve 354, a conduit 355 and a collection box 356. The condensation pipes 351 of the two condensation assemblies 35 are respectively arranged on the left side of the inclined pipe 33 and the right side of the bent pipe 34. The two condensation pipes 351 are both inclined and gradually inclined downward from the inner end to the outer end. The lower port 352 is arranged at the outer end of the condensation pipe 351, the upper port 353 is arranged at the inner end of the condensation pipe 351, the first solenoid valve 354 is arranged at the outer end of the condensation pipe 351, and It is electrically connected to the controller 6, and the conduit 355 is arranged on the outside of the first solenoid valve 354. The collecting box 356 is arranged at the bottom end of the conduit 355. The low-temperature condensed water is injected into the condenser 351 from the lower port 352 through the cold water pipe 53. After the water in the inner cavity of the condenser 351 is filled with condensed water, it flows out from the upper port 353. The high-temperature steam flows from top to bottom in the condenser 351, and the low-temperature condensed water flows from bottom to top to perform heat exchange. The temperature of the condensed water rises after passing through the condenser 351, and the high-temperature steam is pre-cooled and liquefied and enters the collecting box 356 through the conduit 355.

[0020] As a preferred solution, further, Figure 2-3As shown, the upper and lower material components 38 include: a feed pipe 381, a reversing valve 382, a feed pipe 383 and a discharge pipe 384. The feed pipe 381 is arranged at the bottom of the distillation kettle 31 and extends to the bottom of the heating base 2. The reversing valve 382 is arranged at the bottom end of the feed pipe 381 and is electrically connected to the controller 6. The feed pipe 383 is installed on the left side of the bottom of the reversing valve 382, and the discharge pipe 384 is installed on the right side of the bottom of the reversing valve 382. The controller 6 controls the reversing valve 383 to connect the feed pipe 381 with the feed pipe 383, and the mixed liquid flows from the feed pipe 383 into the inner cavity of the distillation kettle 31. The controller 6 controls the reversing valve 382 to close. After the distillation is completed, the controller 6 controls the reversing valve 382 to connect the feed pipe 381 with the discharge pipe 384, and the components with a boiling point higher than 4-chloroacetoacetate are discharged from the discharge pipe 384.

[0021] As a preferred solution, further, Figure 3 As shown in Figure 5, the exhaust mechanism 4 includes: an exhaust pipe 41, a second thermometer 42, a heater 43, a heat-conducting mesh plate 44, a second solenoid valve 45, a connecting pipe 46, a heat exchange box 47 and a gas tank 48. The exhaust pipe 41 is arranged on the rear side of the inner cavity of the distillation kettle 31, and the exhaust pipe 41 extends to the rear side of the distillation kettle 31. The second thermometer 42 is arranged on the outer wall of the exhaust pipe 41 and is electrically connected to the controller 6. The heater 43 is arranged on the rear side of the exhaust pipe 41 and is electrically connected to the controller 6. The heat-conducting mesh plate 44 is arranged on the side wall of the inner cavity of the heater 43. The second solenoid valve 45 is arranged at the rear end of the heater 43 and is electrically connected to the controller 6. The connecting pipe 46 is arranged on the second solenoid valve 45, and the middle part of the connecting pipe 46 is vertically arranged, the heat exchange box 47 is sleeved on the middle part of the connecting pipe 46, and the gas tank 48 is installed at the rear end of the connecting pipe 46. In a specific implementation, the controller 6 controls the second solenoid valve 45 to open, and the inert gas in the gas tank 48 is heated to a temperature slightly lower than that of methyl 4-chloroacetoacetate by the heater 43, which can be set to 200 degrees Celsius in a specific implementation, and is injected into the bottom of the inner cavity of the distillation kettle 31 from the exhaust pipe 41. The second thermometer 42 measures the temperature of the inert gas to ensure that the inert gas is 200 degrees Celsius. With the injection of high-temperature inert gas, the vapor of the residual low-boiling-point component in the inner cavity of the distillation kettle 31 is completely discharged from the bent pipe 34.

[0022] As a preferred solution, further, Figure 7-8As shown, the thermal circulation mechanism 5 includes: a water tank 51, a water pump 52, a cold water pipe 53, a hot water pipe 54 and a return pipe 55. The water tank 51 is arranged on the right side of the heating base 2, and the water pump 52 is installed at the rear bottom of the water tank 51 and is electrically connected to the controller 6. One end of the cold water pipe 53 is arranged at the water outlet end of the water pump 52, and the other end of the cold water pipe 53 is respectively connected to the lower port 352 of the two condensing components 35. There are two hot water pipes 54, one end of which is respectively connected to the upper port 353 of the two condensing components 35, and the other end is connected to the bottom of the heat exchange box 47. One end of the return pipe 55 is arranged at the top of the heat exchange box 47, and the other end is connected to the water tank 51. The high-temperature condensed water passing through the condensing pipe 351 is injected into the heat exchange box 47 through the hot water pipe 54, and preheats the inert gas in the connecting pipe 46, reducing the energy consumption required to heat the inert gas to the set temperature. Then the condensed water flows back to the water tank 51 through the return pipe 55.

[0023] Here’s how it works: Step 1: The controller 6 controls the reversing valve 382 to connect the delivery pipe 381 with the feed pipe 383, and the mixed liquid flows from the feed pipe 383 into the inner cavity of the distillation kettle 31. The controller 6 controls the reversing valve 382 to close, completing the loading; In step 2, the controller 6 controls the heating base 2 to heat the distillation kettle 31. As the temperature continues to rise, the components with lower boiling points in the mixed liquid evaporate and gasify. The first thermometer 37 detects the temperature of the steam. The controller 6 controls the first solenoid valve 354 on the right to open, and the steam rises and enters the bent pipe 34. During the rising section of the bent pipe 34, the high-boiling-point components in the steam are pre-cooled and liquefied. After liquefaction, they flow back to the inner cavity of the distillation kettle 31 along the bent pipe 34. The high-boiling-point components release heat during the liquefaction process, so that the low-boiling-point components maintain a vaporized state and enter the condensation component 35 through the bent pipe 34, completing the recovery of the high-boiling-point components. Step 3: The controller 6 controls the water pump 52 to inject the low-temperature condensed water in the inner cavity of the water tank 51 through the cold water pipe 53 and into the condenser tube 351 from the lower port 352. After the inner cavity of the condenser tube 351 is filled with condensed water, it flows out from the upper port 353. The high-temperature steam flows from top to bottom in the condenser tube 351, and the low-temperature condensed water flows from bottom to top, performing heat exchange. After passing through the condenser tube 351, the temperature of the condensed water increases, and the high-temperature steam is pre-cooled and liquefied, and then enters the collection box 356 through the right conduit 355. Step 4: As the low-boiling-point components in the mixed liquid are evaporated, the temperature in the inner cavity of the still 31 gradually increases. When the first thermometer 37 detects that the temperature has reached the set temperature, the controller 6 controls the second solenoid valve 45 to open. The inert gas in the gas storage tank 48 is heated to the set temperature by the heater 43 and then injected into the bottom of the inner cavity of the still 31 from the exhaust pipe 41. The second thermometer 42 measures the temperature of the inert gas to ensure that the inert gas is at the specified temperature. With the injection of the high-temperature inert gas, the vapor of the remaining low-boiling-point components in the inner cavity of the still 31 is completely discharged from the bent pipe 34. Then, the first solenoid valve 354 and the second solenoid valve 45 on the right are closed, completing the separation of the low-boiling-point components. Step 5: The controller 6 controls the temperature in the inner cavity of the distillation kettle 31 to continue to rise, and the first solenoid valve 354 on the left side is opened. The methyl 4-chloroacetoacetate vapor enters the condensation assembly 35 on the left side through the inclined pipe 33. The condensed liquid methyl 4-chloroacetoacetate flows through the left conduit 355 into the collection box 356 on the left side. In step six, the high-temperature condensed water passing through the condenser 351 is injected into the heat exchange box 47 through the hot water pipe 54, and preheats the inert gas in the connecting pipe 46, thereby reducing the energy consumption required to heat the inert gas to the set temperature. The condensed water then flows back to the water tank 51 through the return pipe 55.

[0024] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with the technology in this field to understand the content of the present invention and implement it. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A purification device for methyl 4-chloroacetoacetate, comprising: A heating base (2) and a controller (6), wherein the controller (6) is fixedly mounted on the front side of the heating base (2), and the heating base (2) and the controller (6) are electrically connected, and is characterized in that it further comprises: A distillation mechanism (3) is fixedly mounted on the top of the heating base (2) and is electrically connected to the controller (6); an exhaust mechanism (4), arranged at the rear side of the distillation mechanism (3) and electrically connected to the controller (6); The heat circulation mechanism (5) is arranged on the right side of the heating base (2) and is electrically connected to the controller (6).

2. A purification device for methyl 4-chloroacetoacetate according to claim 1, characterized in that: The distillation mechanism (3) comprises: a distillation kettle (31), fixedly mounted on the top of the heating base (2); A vertical tube (32) is provided on the top of the distillation kettle (31); An inclined tube (33) is arranged on the left side of the vertical tube (32); A bent tube (34) is arranged on the right side of the vertical tube (32); A plurality of arc-shaped heat conducting plates (36) are circumferentially arranged at the bottom of the inner cavity of the distillation kettle (31); The first temperature detector (37) is arranged at the top of the inner cavity of the vertical tube (32) and is located at the same height as the inclined tube (33) and the bent tube (34), and is electrically connected to the controller (6).

3. A purification device for methyl 4-chloroacetoacetate according to claim 2, characterized in that: The distillation mechanism (3) further comprises: Condensation components (35), two in number, respectively arranged on the left side of the inclined tube (33) and the right side of the bent tube (34); The loading and unloading assembly (38) is arranged at the bottom of the distillation kettle (31) and is electrically connected to the controller (6).

4. A purification device for methyl 4-chloroacetoacetate according to claim 3, characterized in that: The condensation component (35) comprises: Condensation pipe (351), the condensation pipes (351) of the two condensation assemblies (35) are respectively arranged on the left side of the inclined pipe (33) and the right side of the bent pipe (34); A lower port (352) is provided at the outer end of the condenser tube (351); An upper port (353) is provided at the inner end of the condenser tube (351); A first solenoid valve (354) is provided at the outer end of the condenser tube (351) and is electrically connected to the controller (6); A conduit (355) is provided outside the first solenoid valve (354); The collecting box (356) is arranged at the bottom end of the conduit (355).

5. A purification device for methyl 4-chloroacetoacetate according to claim 4, characterized in that: The two condensing pipes (351) are both arranged at an angle and gradually tilt downward from the inner end to the outer end.

6. A purification device for methyl 4-chloroacetoacetate according to claim 5, characterized in that: The loading and unloading assembly (38) comprises: A feed pipe (381) is provided at the bottom of the distillation kettle (31) and extends to the bottom of the heating base (2); A reversing valve (382) is provided at the bottom end of the feed pipe (381) and is electrically connected to the controller (6); A feed pipe (383) is installed on the left side of the bottom of the reversing valve (382); The discharge pipe (384) is installed on the right side of the bottom of the reversing valve (382).

7. A purification device for methyl 4-chloroacetoacetate according to claim 6, characterized in that: The exhaust mechanism (4) comprises: an exhaust pipe (41) disposed at the rear side of the inner cavity of the distillation kettle (31), and the exhaust pipe (41) extends to the rear side of the distillation kettle (31); a second temperature detector (42), disposed on the outer wall of the exhaust pipe (41) and electrically connected to the controller (6); a heater (43) disposed on the rear side of the exhaust pipe (41) and electrically connected to the controller (6); A heat-conducting mesh plate (44) is arranged on the inner cavity side wall of the heater (43); a second solenoid valve (45), disposed at the rear end of the heater (43) and electrically connected to the controller (6); A connecting pipe (46) is arranged at the rear side of the second solenoid valve (45), and the middle portion of the connecting pipe (46) is arranged vertically; A heat exchange box (47) is sleeved on the middle portion of the connecting pipe (46); The gas storage tank (48) is installed at the rear end of the connecting pipe (46).

8. A purification device for methyl 4-chloroacetoacetate according to claim 7, characterized in that: The thermal cycle mechanism (5) comprises: A water tank (51) is arranged on the right side of the heating base (2); A water pump (52) is installed at the rear bottom of the water tank (51) and is electrically connected to the controller (6); A cold water pipe (53), one end of which is arranged at the water outlet of the water pump (52), and the other end of which is respectively connected to the lower ports (352) of the two condensing components (35); Two hot water pipes (54) are connected at one end to the upper ports (353) of the two condensing components (35) and at the other end to the bottom of the heat exchange box (47); A return pipe (55) has one end disposed on the top of the heat exchange box (47) and the other end connected to the water tank (51).

9. A method for purifying methyl 4-chloroacetoacetate, which is applied to the purification device for methyl 4-chloroacetoacetate according to claim 8, characterized in that: The following steps are involved: Step 1: The controller (6) controls the reversing valve (382) to connect the delivery pipe (381) to the feed pipe (383), and the mixed liquid flows from the feed pipe (383) into the inner cavity of the distillation kettle (31). The controller (6) controls the reversing valve (382) to close, and the loading is completed; Step 2: The controller (6) controls the heating base (2) to heat the distillation kettle (31). As the temperature continues to rise, the components with lower boiling points in the mixed liquid evaporate and gasify. The first temperature detector (37) detects the temperature of the steam. The controller (6) controls the first solenoid valve (354) located on the right to open, and the steam rises and enters the bending pipe (34). During the rising section of the bending pipe (34), the high-boiling-point components in the steam are pre-cooled and liquefied. After liquefaction, they flow back to the inner cavity of the distillation kettle (31) along the bending pipe (34). The high-boiling-point components release heat during the liquefaction process, so that the low-boiling-point components maintain a gasified state and enter the condensation component (35) through the bending pipe (34), completing the recovery of the high-boiling-point components. Step 3: The controller (6) controls the water pump (52) to inject the low-temperature condensed water in the inner cavity of the water tank (51) through the cold water pipe (53) and inject it into the condenser (351) from the lower port (352). After the inner cavity of the condenser (351) is filled with the condensed water, it flows out from the upper port (353). The high-temperature steam flows from top to bottom in the condenser (351), and the low-temperature condensed water flows from bottom to top to perform heat exchange. After the condensed water passes through the condenser (351), the temperature rises, and the high-temperature steam is pre-cooled and liquefied, and enters the collection box (356) through the right conduit (355); Step 4: As the low-boiling-point components in the mixed liquid are evaporated, the temperature in the inner cavity of the distillation kettle (31) gradually increases. When the first thermometer (37) detects that the temperature reaches the set temperature, the controller (6) controls the second solenoid valve (45) to open. The inert gas in the gas storage tank (48) is heated to the set temperature by the heater (43) and then injected into the bottom of the inner cavity of the distillation kettle (31) from the exhaust pipe (41). The second thermometer (42) measures the temperature of the inert gas to ensure that the inert gas is at the specified temperature. As the high-temperature inert gas is injected, the steam of the low-boiling-point components remaining in the inner cavity of the distillation kettle (31) is completely discharged from the bent pipe (34). Then, the first solenoid valve (354) and the second solenoid valve (45) on the right are closed, completing the separation of the low-boiling-point components. Step 5: The controller (6) controls the temperature in the inner cavity of the still (31) to continue to rise, and the first solenoid valve (354) on the left side is opened. The methyl 4-chloroacetoacetate vapor enters the condensation assembly (35) on the left side through the inclined tube (33), and the condensed liquid methyl 4-chloroacetoacetate flows into the collection box (356) on the left side through the left conduit (355); In step six, the high-temperature condensed water passing through the condenser (351) is injected into the heat exchange tank (47) through the hot water pipe (54), and preheats the inert gas in the connecting pipe (46), thereby reducing the energy consumption required to heat the inert gas to the set temperature. The condensed water then flows back to the water tank (51) through the return pipe (55).

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