A device for heating reflux reaction

Abstract

The utility model relates to a device for heating reflux reaction. Specifically, the utility model provides a device for heating reflux reaction, the device comprising a reaction kettle, a reflux pipe and a liquid collection tank. The device for heating reflux reaction described in the utility model can be used to effectively condense the solvent gas volatilized in the heating reflux reaction into liquid, so that the heating reflux reaction can be effectively carried out.

Description

Technical Field

[0001] The utility model relates to the field of chemical industry, in particular to a device for heating reflux reaction. Background Art

[0002] Heating reflux reaction is a common reaction in the chemical industry. In the heating reflux reaction, volatile solvent gas such as organic solvent gas such as alcohol solvent is condensed into liquid by a condenser and then refluxed into the reaction liquid, so that the reaction continues. For example, in the preparation process of iopamidol crystals, iopamidol is often added to an alcohol solvent such as ethanol or methanol, heated under reflux reaction, and then cooled to obtain iopamidol crystals.

[0003] In the heating reflux reaction, condensing the volatile solvent gas into liquid is a key step. If the effect of condensing the volatile solvent gas into liquid becomes worse, the heating reflux reaction will be affected. Therefore, in the heating reflux reaction, how to effectively condense the volatile solvent gas into liquid has become a research hotspot in the chemical industry.

[0004] Therefore, there is a need in the art to develop a device for heating reflux reaction, which can be used to effectively condense the volatilized solvent gas in the heating reflux reaction into liquid, so that the heating reflux reaction can be carried out effectively. Utility Model Content

[0005] The utility model aims to provide a device for heating reflux reaction, which can be used to effectively condense the volatilized solvent gas in the heating reflux reaction into liquid, so that the heating reflux reaction can be effectively carried out.

[0006] In a first aspect, the utility model provides a device for heating reflux reaction, the device comprising a reaction kettle 1, a reflux pipe 2 and a liquid collection tank 3;

[0007] The bottom of the reflux pipe is in communication with the reactor chamber of the reactor, and the body of the reflux pipe contains a first condenser, which includes a first condenser pipe 4;

[0008] The top of the reflux pipe is a closed end, and the top of the reflux pipe is connected to the liquid collection tank through a gas pipe 5. A second condenser 6 is provided on the gas pipe. The liquid collection tank is provided with a liquid pipe 7. One end of the liquid pipe is connected to the bottom of the liquid collection tank, and the other end of the liquid pipe passes through the pipe wall of the reflux pipe and is connected to a spray head 8. The spray head is located above the first condenser.

[0009] The reflux pipe has one or more liquid distribution plates 9 in its body. The liquid distribution plates are provided with one or more through holes 10. The liquid distribution plates are located between the spray head and the first condenser.

[0010] In another preferred example, the first condenser tubes are arranged in upper and lower tube bundles.

[0011] In another preferred example, the first condenser includes a condenser inlet 11 and a condenser outlet 12 .

[0012] In another preferred example, the condenser inlet is located below the condenser outlet.

[0013] In another preferred example, the condenser inlet and the condenser outlet pass through the side wall of the reflux pipe.

[0014] In another preferred example, the condenser inlet and the condenser outlet are sealed and connected to the side wall of the reflux pipe.

[0015] In another preferred example, the first condenser contains a first condensate.

[0016] In another preferred example, the first condensate includes water.

[0017] In another preferred embodiment, the temperature of the first condensate is 8-12°C.

[0018] In another preferred example, the second condenser contains a second condensate.

[0019] In another preferred example, the second condenser includes an inner tube and an outer tube, the outer tube covers the inner tube, a tube cavity is formed between the outer tube and the inner tube, the two end openings of the inner tube are connected to the gas tube, and a lower liquid inlet and an upper liquid outlet are provided on the tube wall of the outer tube.

[0020] In another preferred embodiment, the inner tube includes a spiral tube or a straight tube.

[0021] In another preferred embodiment, the number of the inner tubes is one or more.

[0022] In another preferred embodiment, there are multiple inner tubes, and the inner tubes are arranged parallel to each other.

[0023] In another preferred example, the lumen formed between the outer tube and the inner tube contains a second condensate.

[0024] In another preferred example, the second condensate includes ethylene glycol.

[0025] In another preferred example, the temperature of the second condensate is -8°C to -6°C.

[0026] In another preferred embodiment, the shower head is located in the lumen of the return pipe.

[0027] In another preferred embodiment, the shower head contains one or more nozzles.

[0028] In another preferred embodiment, the bottom of the reflux pipe is connected to the reactor chamber of the reactor through a pipeline.

[0029] In another preferred embodiment, the reflux pipe is located above the reactor.

[0030] In another preferred example, the liquid collection tank is located above the shower head.

[0031] In another preferred embodiment, the liquid distribution plate comprises a flat plate.

[0032] In another preferred embodiment, the liquid distribution plate is connected to the inner wall of the tube body of the reflux tube.

[0033] In another preferred embodiment, the liquid distribution plates are arranged in parallel from top to bottom.

[0034] In another preferred example, there are spaces between each liquid distribution plate.

[0035] In another preferred embodiment, the through holes of each liquid distribution plate correspond to each other or do not correspond to each other.

[0036] In another preferred embodiment, a liquid pump 13 is provided on the liquid pipe.

[0037] In another preferred embodiment, the device further includes a pressure controller.

[0038] In another preferred embodiment, the pressure controller includes a capillary tube 14, one end of the capillary tube is an open end, and the other end of the capillary tube is a closed end. The open end of the capillary tube is communicated with the reactor chamber of the reactor. A sliding plug 15 is provided in the chamber of the capillary tube. The sliding plug is sealed with the inner wall of the chamber of the capillary tube. One end of the sliding plug is connected to the inner wall of the closed end of the capillary tube through a reset spring 16. A perforation 17 is provided on the side wall of the capillary tube.

[0039] When the reactor chamber of the reactor is communicated with the outside atmosphere, the sliding plug blocks the through hole.

[0040] In another preferred embodiment, the increase in the air pressure in the reactor chamber of the reactor can cause the sliding plug to slide along the inner wall of the tube chamber of the capillary toward the direction of the return spring.

[0041] In another preferred embodiment, the capillary tube comprises a cylindrical tube.

[0042] In another preferred embodiment, the open end of the capillary tube is connected to the cavity wall of the reactor.

[0043] In another preferred embodiment, the capillary tube is located above the reactor.

[0044] In another preferred embodiment, the open end of the capillary tube is vertically connected to the cavity wall of the reactor.

[0045] In another preferred embodiment, the capillary is a transparent capillary.

[0046] In another preferred example, the sliding plug is sealingly connected to the inner wall of the tube side cavity of the capillary tube.

[0047] In another preferred embodiment, one end of the sliding plug is vertically connected to the inner wall of the closed end of the capillary tube via a return spring.

[0048] In another preferred embodiment, scale lines are provided on the side wall of the capillary.

[0049] In another preferred embodiment, the scale line can quantitatively indicate the air pressure in the reactor chamber of the reactor.

[0050] In another preferred embodiment, the gas pressure in the kettle chamber is quantitatively indicated by the position of the bottom outer wall of the sliding plug corresponding to the scale line.

[0051] In another preferred example, the sliding plug is a cylindrical sliding plug.

[0052] In another preferred embodiment, the sliding plug can slide along the inner wall of the lumen of the capillary tube.

[0053] In another preferred embodiment, the sliding plug can slide freely along the inner wall of the lumen of the capillary tube.

[0054] In another preferred embodiment, the perforations are connected to the exhaust gas collector or processor via an exhaust gas pipe 18 .

[0055] In another preferred embodiment, the waste gas collector or processor collects or processes the waste gas from the reactor chamber of the reactor.

[0056] In another preferred embodiment, the waste gas collector or processor is located outside the outer wall of the reactor chamber of the reactor and the outer wall of the capillary tube.

[0057] In another preferred embodiment, the plurality is 2 or more, such as 2-8 or 5-10.

[0058] In another preferred example, the device further comprises a stirrer.

[0059] In another preferred embodiment, the agitator is capable of stirring the kettle cavity.

[0060] In another preferred example, the device further comprises a heater.

[0061] In another preferred example, the heater is capable of heating the kettle cavity.

[0062] In another preferred embodiment, the reactor further includes a gas release valve.

[0063] In another preferred embodiment, the air release valve is capable of releasing air from the kettle chamber.

[0064] In another preferred example, the connection or connection includes communication.

[0065] In another preferred embodiment, the connection or connection is a fixed connection or a detachable connection.

[0066] It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described below (such as embodiments) can be combined with each other to form new or preferred technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] It should be understood that the drawings are only used for illustrative purposes and should not be construed as limitations on this patent; in order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted; the same or similar numbers correspond to the same or similar parts; the terms describing the positional relationship in the drawings are only used for illustrative purposes and should not be construed as limitations on this patent.

[0068] Figure 1 It is a device for heating reflux reaction in a preferred embodiment of the utility model.

[0069] Wherein, each number in the accompanying drawings represents:

[0070] 1 is a reaction kettle, 2 is a reflux pipe, 3 is a liquid collecting tank, 4 is a first condenser, 5 is a gas pipe, 6 is a second condenser, 7 is a liquid pipe, 8 is a spray head, 9 is a liquid distribution plate, 10 is a through hole, 11 is a condenser inlet, 12 is a condenser outlet, 13 is a liquid pump, 14 is a capillary tube, 15 is a sliding plug, 16 is a return spring, 17 is a perforation and 18 is an exhaust pipe. DETAILED DESCRIPTION

[0071] After extensive and in-depth research, the inventor has developed a device for heating reflux reaction, which includes a reactor, a reflux pipe and a liquid collection tank. The device for heating reflux reaction of the utility model can be used to effectively condense the solvent gas volatilized in the heating reflux reaction into liquid, so that the heating reflux reaction can be effectively carried out.

[0072] the term

[0073] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0074] As used herein, the terms "include", "comprises", and "comprising" are used interchangeably, and include not only open definitions, but also semi-closed and closed definitions. In other words, the terms include "consisting of", "consisting essentially of".

[0075] As used herein, the terms "upper", "lower" and "side" etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the invention of the utility model.

[0076] As used herein, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, it is defined that features such as "first" and "second" may explicitly or implicitly include one or more of the features.

[0077] As used herein, the terms “connected” and “connected” should be understood in a broad sense, and may refer to fixed connection or connection, detachable connection or connection, or integral connection or connection.

[0078] For the sake of convenience, the following Figure 1 To further describe the present invention, it should be understood that the accompanying drawings do not limit the scope of the present invention.

[0079] The utility model provides a device for heating reflux reaction, the device comprising a reaction kettle 1, a reflux pipe 2 and a liquid collection tank 3;

[0080] The bottom of the reflux pipe is in communication with the reactor chamber of the reactor, and the body of the reflux pipe contains a first condenser, which includes a first condenser pipe 4;

[0081] The top of the reflux pipe is a closed end, and the top of the reflux pipe is connected to the liquid collection tank through a gas pipe 5. A second condenser 6 is provided on the gas pipe. The liquid collection tank is provided with a liquid pipe 7. One end of the liquid pipe is connected to the bottom of the liquid collection tank, and the other end of the liquid pipe passes through the pipe wall of the reflux pipe and is connected to a spray head 8. The spray head is located above the first condenser.

[0082] The reflux pipe has one or more liquid distribution plates 9 in its body. The liquid distribution plates are provided with one or more through holes 10. The liquid distribution plates are located between the spray head and the first condenser.

[0083] The device for heating reflux reaction of the utility model can be used to effectively condense the volatilized solvent gas in the heating reflux reaction into liquid, so that the heating reflux reaction can be effectively carried out. A typical working principle is as follows:

[0084] Specifically, the preparation of iopamidol crystals by adding iopamidol and ethanol solvent into a reactor, heating under reflux reaction, and cooling is described as follows:

[0085] The first condenser tube of the first condenser is filled with circulating water at 8-12°C, and the second condenser is filled with circulating ethylene glycol at -8°C to -6°C. During the heating reflux reaction, most of the volatilized ethanol solvent gas is first condensed into liquid through the first condenser tube in the tube body of the reflux tube and refluxed into the reaction liquid in the reactor. Then, the ethanol solvent gas that is not condensed into liquid by the first condenser tube is condensed into ethanol solvent liquid with a lower temperature through the gas tube to the second condenser. The ethanol solvent liquid with a lower temperature condensed by the second condenser enters the liquid collection tank. The ethanol solvent liquid with a lower temperature collected in the liquid collection tank is discharged from the liquid tube. The spray head sprays out, and the ethanol solvent liquid with a lower temperature sprayed by the spray head can cool the liquid distribution plate, so that the liquid distribution plate is at a lower temperature. The liquid distribution plate with a lower temperature can further condense the volatilized ethanol solvent gas in the reflux pipe into liquid. Therefore, the first condenser, the second condenser and the liquid distribution plate can condense the volatilized ethanol solvent gas into liquid, and then reflux it into the reaction liquid in the reactor. Therefore, the device for heating reflux reaction described in the utility model can be used to effectively condense the volatilized solvent gas in the heating reflux reaction into liquid, so that the heating reflux reaction can be carried out effectively.

[0086] In the heating reflux reaction, the condensation part (such as the condenser) needs to be in a low temperature state to ensure that the volatilized solvent gas is condensed into liquid and refluxed into the reaction liquid. If the temperature of the condensation part is too high, it is difficult to effectively condense the volatilized solvent gas into liquid, thereby affecting the heating reflux reaction. However, in industrial production, a large amount of energy is often required to cool the circulating condensate after passing through the condensation part, so that the condensation part is in a low temperature state, thereby achieving the effective condensation of the volatilized solvent gas into liquid by the condensation part. Therefore, keeping the condensation part in a low temperature state is often a high energy consumption. How to achieve efficient condensation of the volatilized solvent gas into liquid can reduce energy consumption, save energy, and thus reduce reaction costs. In the device for heating reflux reaction described in the utility model, the temperature of the second condenser can be made lower than the temperature of the first condenser. For example, the first condenser tube of the first condenser can be filled with circulating water at 8-12°C, and the second condenser can be filled with circulating ethylene glycol at -8°C to -6°C. Usually, most of the volatile solvent gas is condensed into liquid through the first condenser tube and refluxed into the reaction liquid in the reactor, and only a small part of the volatile solvent gas is condensed into liquid through the second condenser. Therefore, using a second condenser containing a relatively small amount of low-temperature condensate (such as circulating ethylene glycol at -8°C to -6°C) can achieve condensation of a small part of the volatile solvent gas through the second condenser into liquid. Those skilled in the art should know that the lower the temperature of the condensate, the higher the energy consumption required (that is, more energy consumption is often required to cool the circulating condensate flowing through the condenser to maintain the low temperature state of the condensate). Therefore, in the device for heating reflux reaction described in the utility model, using a second condenser containing a relatively small amount of low-temperature condensate (such as circulating ethylene glycol at -8°C to -6°C) can reduce energy consumption and save energy. In addition, the solvent liquid condensed by the second condenser containing a relatively low temperature condensate (such as circulating ethylene glycol filled at -8°C to -6°C) is usually at a relatively low temperature. After entering the liquid collection tank, it is sprayed out from the spray head through the liquid pipe. The relatively low temperature solvent liquid sprayed out by the spray head can cool the liquid distribution plate, so that the liquid distribution plate is at a relatively low temperature. The relatively low temperature liquid distribution plate can further condense the solvent gas volatilized in the reflux pipe into liquid, thereby realizing the further utilization of the relatively low temperature solvent liquid condensed by the second condenser, saving energy consumption. Therefore, the device for heating the reflux reaction described in the utility model can reduce the energy consumption used for condensation, thereby reducing the reaction cost.

[0087] In the device of the utility model, when used for heating reflux reaction, the temperature of the second condenser can be set to be lower than the temperature of the first condenser. The condensate of the first condenser tube can be water, and the temperature can be set to 8-12°C; the second condenser contains a second condensate, and the second condensate can be ethylene glycol, and the temperature of the second condensate can be set to -8°C to -6°C.

[0088] In a preferred example of the utility model of the present invention, the device further comprises a pressure controller. Preferably, the pressure controller comprises a capillary tube, one end of the capillary tube is an open end, the other end of the capillary tube is a closed end, the open end of the capillary tube is in communication with the reactor chamber of the reactor, a sliding plug is provided in the tube chamber of the capillary tube, the sliding plug is sealedly connected with the inner wall of the tube chamber of the capillary tube, one end of the sliding plug is connected with the inner wall of the tube chamber of the closed end of the capillary tube through a reset spring, and a perforation is provided on the tube side wall of the capillary tube; when the reactor chamber of the reactor is in communication with the outside atmosphere, the sliding plug blocks the perforation. The increase of the pressure in the reactor chamber of the reactor can make the sliding plug slide along the inner wall of the tube chamber of the capillary tube in the direction of the reset spring. It should be understood by those skilled in the art that the pressure in the reactor chamber of the reactor can be adjusted by adjusting factors such as the reset spring (such as the elastic coefficient and stiffness) and the weight of the sliding plug to achieve that when the pressure in the reactor chamber of the reactor exceeds a specific value, the tube chamber of the capillary tube below the bottom of the sliding plug is in communication with the perforation, which are all conventional technical operation means in the art. In the heating reflux reaction, the appearance of abnormal factors (such as abnormal heating of the reactor causing the temperature of the reactor chamber to rise, etc.) can easily cause the pressure of the reactor chamber to rise continuously, thus causing safety problems. The pressure controller described in the utility model can be used to avoid safety problems caused by excessive pressure in the reactor chamber. If abnormal factors (such as abnormal heating of the reactor causing the temperature of the reactor chamber to rise, etc.) cause the pressure of the reactor chamber to rise continuously, the sliding plug can slide along the inner wall of the tube cavity of the capillary toward the direction of the reset spring. When the pressure of the reactor chamber rises to a certain value, the tube cavity of the capillary under the bottom of the sliding plug is connected to the perforation, and the high-pressure gas in the reactor chamber will be discharged in time through the perforation, so that the pressure of the reactor chamber will no longer increase, thereby avoiding safety problems caused by excessive pressure in the reactor chamber.

[0089] In a preferred example of the present invention, the capillary tube is a transparent capillary tube, through which the sliding of the sliding plug on the inner wall of the lumen of the capillary tube can be easily observed.

[0090] In a preferred example of the present invention, scale lines are provided on the side walls of the capillary tube, and the gas pressure in the kettle chamber can be quantitatively indicated by the position of the bottom outer wall of the sliding plug corresponding to the scale lines.

[0091] In a preferred embodiment of the present invention, the perforation is connected to the waste gas collector or processor through a waste gas pipe. The waste gas collector or processor can collect or process waste gas (such as volatile solvent) from the reactor chamber of the reactor to avoid environmental pollution.

[0092] In a preferred embodiment of the present invention, a liquid pump is provided on the liquid pipe, and the liquid pump can transport the liquid in the liquid collection tank to the spray head for spraying.

[0093] The main excellent technical effects of the utility model include:

[0094] The utility model develops a reaction kettle. The device can be used to effectively condense the volatilized solvent gas in the heating reflux reaction into liquid, so that the heating reflux reaction can be effectively carried out.

[0095] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0096] Example 1

[0097] This embodiment 1 provides a device for heating reflux reaction, the device comprising a reaction kettle 1, a reflux pipe 2 and a liquid collection tank 3;

[0098] The bottom of the reflux pipe is in communication with the reactor chamber of the reactor, and the body of the reflux pipe contains a first condenser, which includes a first condenser pipe 4;

[0099] The top of the reflux pipe is a closed end, and the top of the reflux pipe is connected to the liquid collection tank through a gas pipe 5. A second condenser 6 is provided on the gas pipe. The liquid collection tank is provided with a liquid pipe 7. One end of the liquid pipe is connected to the bottom of the liquid collection tank, and the other end of the liquid pipe passes through the pipe wall of the reflux pipe and is connected to a spray head 8. The spray head is located above the first condenser.

[0100] The reflux pipe contains one or more liquid distribution plates 9, and one or more through holes 10 are provided on the liquid distribution plates. The liquid distribution plates are located between the spray head and the first condenser.

[0101] The device further comprises a pressure controller, which comprises a capillary tube 14, one end of which is an open end and the other end of which is a closed end. The open end of the capillary tube communicates with the reactor chamber of the reactor. A sliding plug 15 is provided in the chamber of the capillary tube, and the sliding plug is sealedly connected to the inner wall of the chamber of the capillary tube. One end of the sliding plug is connected to the inner wall of the closed end of the capillary tube via a reset spring 16. A perforation 17 is provided on the side wall of the capillary tube.

[0102] When the reactor chamber of the reactor is communicated with the outside atmosphere, the sliding plug blocks the through hole.

[0103] In the device described in this embodiment, when the device is used for heating reflux reaction, the temperature of the second condenser can be set to be lower than the temperature of the first condenser (for example, the first condenser tube of the first condenser is filled with circulating water at 8-12°C, and the second condenser is filled with circulating ethylene glycol at -8°C to -6°C). Most of the volatile solvent gas is first condensed into liquid through the first condenser tube in the tube body of the reflux tube and refluxed into the reaction liquid in the reactor. Then, the solvent gas that is not condensed into liquid by the first condenser tube is condensed into a solvent liquid with a lower temperature through the gas tube to the second condenser. The solvent liquid with a lower temperature condensed by the second condenser enters the liquid collection tank. The liquid collection tank The solvent liquid with a lower temperature collected is sprayed out from the spray head through the liquid pipe. The solvent liquid with a lower temperature sprayed out from the spray head can cool down the liquid distribution plate, so that the liquid distribution plate is at a lower temperature. The liquid distribution plate with a lower temperature can further condense the solvent gas volatilized in the reflux pipe into liquid. Therefore, the first condenser, the second condenser and the liquid distribution plate can condense the volatilized solvent gas into liquid, and then reflux it into the reaction liquid in the reactor. Therefore, the device for heating reflux reaction described in this embodiment can be used to effectively condense the solvent gas volatilized in the heating reflux reaction into liquid, so that the heating reflux reaction can be carried out effectively.

[0104] The device for heating reflux reaction described in this embodiment can also be used to avoid safety problems caused by excessive air pressure in the kettle chamber of the reactor. If abnormal factors (such as abnormal heating of the reactor causing the temperature of the kettle chamber to rise, etc.) cause the air pressure in the kettle chamber of the reactor to continue to rise, the sliding plug can slide along the inner wall of the lumen of the capillary tube in the direction of the reset spring. When the air pressure in the kettle chamber rises to a certain value, the lumen of the capillary tube below the bottom of the sliding plug is connected to the perforation, and the high-pressure gas in the kettle chamber will be discharged in time through the perforation, so that the air pressure in the kettle chamber will no longer increase, thereby avoiding safety problems caused by excessive air pressure in the kettle chamber of the reactor.

[0105] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A device for heating reflux reaction, characterized in that: The device comprises a reaction kettle (1), a reflux pipe (2) and a liquid collection tank (3); The bottom of the reflux pipe is in communication with the reactor chamber of the reactor, and the body of the reflux pipe contains a first condenser, which includes a first condenser pipe (4); The top of the reflux pipe is a closed end. The top of the reflux pipe is connected to the liquid collection tank via a gas pipe (5). A second condenser (6) is provided on the gas pipe. The liquid collection tank is provided with a liquid pipe (7). One end of the liquid pipe is connected to the bottom of the liquid collection tank. The other end of the liquid pipe passes through the wall of the reflux pipe and is connected to a spray head (8). The spray head is located above the first condenser. The reflux pipe has one or more liquid distribution plates (9) in its body, and one or more through holes (10) are provided on the liquid distribution plates. The liquid distribution plates are located between the spray head and the first condenser.

2. The device for heating reflux reaction according to claim 1, characterized in that: The first condenser tubes are arranged in upper and lower tube bundles.

3. The device for heating reflux reaction according to claim 1, characterized in that: The first condenser contains a first condensate, and the temperature of the first condensate is 8-12° C.; and / or The second condenser contains a second condensate, and the temperature of the second condensate is -8°C to -6°C.

4. The device for heating reflux reaction according to claim 1, characterized in that: The second condenser comprises an inner tube and an outer tube, the outer tube covers the inner tube, a tube cavity is formed between the outer tube and the inner tube, the two ends of the inner tube are connected to the gas tube, and a lower liquid inlet and an upper liquid outlet are provided on the tube wall of the outer tube.

5. The device for heating reflux reaction according to claim 1, characterized in that: The liquid distribution plate comprises a flat plate.

6. The device for heating reflux reaction according to claim 1, characterized in that: The liquid pipe is provided with a liquid pump (13).

7. The device for heating reflux reaction according to claim 1, characterized in that: The device also includes a pressure controller, which includes a capillary tube (14), one end of which is an open end and the other end of which is a closed end, the open end of which is in communication with the reactor chamber of the reactor, a sliding plug (15) is provided in the chamber of the capillary tube, the sliding plug is sealedly connected to the inner wall of the chamber of the capillary tube, one end of the sliding plug is connected to the inner wall of the closed end of the capillary tube via a reset spring (16), and a perforation (17) is provided on the side wall of the capillary tube; When the reactor chamber of the reactor is communicated with the outside atmosphere, the sliding plug blocks the through hole.

8. The device for heating reflux reaction according to claim 7, characterized in that: The increase of the air pressure in the reactor chamber of the reactor can cause the sliding plug to slide along the inner wall of the tube chamber of the capillary toward the direction of the return spring.

9. The device for heating reflux reaction according to claim 7, characterized in that: The capillary comprises a cylindrical tube.

10. The device for heating reflux reaction according to claim 7, characterized in that: The capillary is a transparent capillary.

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