A 5-chlorosalicylic acid synthesis system

Abstract

The utility model discloses a 5-chlorosalicylic acid synthesis system, which comprises a chlorine buffer tank, a nitrogen buffer tank, a gas mixer, a reactor and an annular distributor; the annular distributor is horizontally fixed at the bottom of the reactor; the outlet of the chlorine buffer tank is communicated with the chlorine inlet of the gas mixer through a first pipeline, a chlorine regulating valve and a first rotor flowmeter are arranged on the first pipeline, the outlet of the nitrogen buffer tank is communicated with the nitrogen inlet of the gas mixer through a second pipeline, a nitrogen regulating valve and a second rotor flowmeter are arranged on the second pipeline, the outlet of the gas mixer is communicated with a third pipeline, and the third pipeline passes through the top wall of the reactor and is communicated with the inlet of the annular distributor.

Description

Technical field:

[0001] The utility model relates to the technical field of 5-chlorosalicylic acid synthesis, in particular to a 5-chlorosalicylic acid synthesis system. Background technology:

[0002] The synthesis process of 5-chlorosalicylic acid is as follows: salicylic acid and chlorobenzene are added into a reaction kettle, and then the temperature is raised to dissolve, and at a high temperature of 110-120°C, a chlorine gas pipeline is inserted under the reaction liquid to pass chlorine to synthesize 5-chlorosalicylic acid.

[0003] The above process has the following problems: First, during the chlorination process, chlorine needs to be in full contact with the reaction liquid. Since the gas cannot react instantly, chlorine bubbles will rise and overflow the reaction liquid. To avoid the above situation, the chlorine pipeline is generally inserted into the middle and lower part of the reaction liquid, and chlorine with a certain pressure is passed into the reactor through the chlorine pipeline. At the end of the chlorination reaction, if the amount of chlorine used is reduced by reducing the flow rate and pressure of chlorine, the reaction liquid will adhere to the outlet position of the chlorine pipeline, and even enter the chlorine pipeline, forming back suction, blocking the outlet of the chlorine pipeline, causing danger; if the original flow rate and pressure are maintained, chlorine will be locally excessive at the outlet of the chlorine pipeline, forming too many chlorine impurities. Second, if the chlorine pipeline is made of stainless steel or titanium alloy alone, it is easily corroded and deformed by the high-temperature chlorinated liquid at a high temperature of 110-120°C, and the service life is short. Utility model content:

[0004] The utility model aims to provide a 5-chlorosalicylic acid synthesis system.

[0005] The purpose of the utility model is implemented by the following technical scheme: a 5-chlorosalicylic acid synthesis system, which includes a chlorine buffer tank, a nitrogen buffer tank, a gas mixer, a reactor and an annular distributor; the annular distributor is horizontally fixed at the bottom of the reactor; the outlet of the chlorine buffer tank is connected to the chlorine inlet of the gas mixer through a first pipeline, a chlorine regulating valve and a first rotor flowmeter are arranged on the first pipeline, the outlet of the nitrogen buffer tank is connected to the nitrogen inlet of the gas mixer through a second pipeline, a nitrogen regulating valve and a second rotor flowmeter are arranged on the second pipeline, the outlet of the gas mixer is connected to a third pipeline, and the third pipeline passes through the top wall of the reactor and is connected to the inlet of the annular distributor.

[0006] Preferably, a driving motor is externally provided on the top of the reactor, and an agitator is provided inside the reactor. The rotating shaft of the agitator passes through the top wall of the reactor and is fixedly connected to the output shaft of the driving motor, and the blades of the agitator are placed at the center of the annular distributor.

[0007] Preferably, the annular distributor is composed of an annular pipe, the outlet of the third pipeline is connected to the top of the annular pipe, and a plurality of air holes are evenly opened in the circumferential direction on the inner circle of the annular pipe.

[0008] Preferably, the annular pipe is a double-layer composite pipe lined with titanium alloy and covered with polytetrafluoroethylene.

[0009] The utility model has the following advantages: the utility model is provided with a chlorine buffer tank, a nitrogen buffer tank, a gas mixer, a reactor and an annular distributor. Chlorine is transported from the chlorine buffer tank to the gas mixer, and nitrogen is transported from the nitrogen buffer tank to the gas mixer. In the gas mixer, nitrogen and chlorine are fully mixed. In the process of gas transportation, the chlorine regulating valve and the nitrogen regulating valve are both controlled by a controller. The chlorine regulating valve automatically adjusts the flow rate of chlorine from large to small, and the nitrogen regulating valve automatically adjusts the flow rate of nitrogen from small to large. After nitrogen and chlorine are uniformly mixed in the gas mixer, they always enter the annular distributor at a constant pressure and are discharged from the air holes of the annular distributor toward the agitator. The discharged bubbles always remain normal, and there will be no situation of fluctuating pressure, thus avoiding the formation of back suction. Moreover, at the end of the chlorination reaction, the amount of chlorine used is reduced, and no excessive polychlorine impurities are formed. In the process of the mixed gas entering the reaction liquid, the driving motor is started, and the agitator stirs the reaction liquid, so that the chlorine is quickly dissolved in the reaction liquid, thereby solving the problem of uneven chlorine flow. Description of the drawings:

[0010] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creativity and labor.

[0011] Figure 1 It is a structural schematic diagram of the utility model.

[0012] The components in the accompanying drawings are marked as follows: chlorine buffer tank 1, nitrogen buffer tank 2, gas mixer 3, reactor 4, annular distributor 5, air hole 5.1, drive motor 6, stirrer 7, first pipeline 8, chlorine regulating valve 9, first rotor flowmeter 10, second pipeline 11, nitrogen regulating valve 12, second rotor flowmeter 13, third pipeline 14. Specific implementation method:

[0013] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0014] like Figure 1 As shown, a 5-chlorosalicylic acid synthesis system comprises a chlorine buffer tank 1, a nitrogen buffer tank 2, a gas mixer 3, a reaction kettle 4 and a ring distributor 5;

[0015] An annular distributor 5 is horizontally fixed at the bottom of the reactor 4. The annular distributor 5 is composed of an annular pipe, which is a double-layer composite pipe lined with titanium alloy and covered with polytetrafluoroethylene. Titanium alloy is a structural metal with high strength, good corrosion resistance and high heat resistance. Polytetrafluoroethylene has the advantages of acid and alkali resistance and high temperature resistance, and is almost insoluble in all solvents, which can extend the service life of the annular pipe. A plurality of air holes 5.1 are evenly opened in the inner ring of the annular pipe along the circumferential direction;

[0016] A driving motor 6 is provided outside the top of the reactor 4, and a stirrer 7 is provided inside the reactor 4. The rotating shaft of the stirrer 7 passes through the top wall of the reactor 4 and is fixedly connected to the output shaft of the driving motor 6. The blades of the stirrer 7 are placed at the center of the annular distributor 5. When the driving motor 6 is started, the stirrer 7 stirs the reaction liquid to make the reaction liquid more uniform, which is conducive to the reaction. The top of the reactor 4 is also provided with a salicylic acid inlet, a chlorobenzene inlet and an exhaust port;

[0017] The outlet of the chlorine buffer tank 1 is connected to the chlorine inlet of the gas mixer 3 through a first pipeline 8, on which a chlorine regulating valve 9 and a first rotor flowmeter 10 are arranged, the chlorine regulating valve 9 is controlled by a controller, and automatically adjusts the flow rate of chlorine from large to small, the first rotor flowmeter 10 can measure the rotor rotation speed of chlorine in the pipeline to display the flow rate of chlorine, the outlet of the nitrogen buffer tank 2 is connected to the nitrogen inlet of the gas mixer 3 through a second pipeline 11, on which a nitrogen regulating valve 12 and a second rotor flowmeter 13 are arranged, the nitrogen regulating valve 12 is controlled by a controller, and automatically adjusts the flow rate of nitrogen from small to large, and nitrogen is used as a supplementary gas, and when the chlorine flow rate decreases, it can ensure that the overall gas pressure of the transport remains unchanged, The second rotor flowmeter 13 can measure the rotor rotation speed of nitrogen in the pipeline to determine the flow rate of nitrogen. The outlet of the gas mixer 3 is connected to the third pipeline 14. The third pipeline 14 passes through the top wall of the reactor 4 and is connected to the inlet of the annular pipeline. A mixed gas regulating valve is provided on the third pipeline 14. The gas mixer 3 can fully mix the nitrogen and the chlorine. The mixed gas enters the annular distributor 5 through the third pipeline 14 and is discharged from the air hole 5.1 of the annular distributor 5 toward the agitator 7. The drive motor 6 is started, and the agitator 7 stirs the reaction liquid to dissolve the chlorine in the reaction liquid, thereby solving the problem of uneven chlorine flow. In the process of the mixed gas entering the annular distributor 5, it can be ensured that the amount of chlorine used is reduced without changing the gas pressure.

[0018] Working process: chlorine in the chlorine buffer tank 1 enters the gas mixer 3 through the first pipeline 8, the chlorine regulating valve 9 is controlled by the controller to automatically adjust the flow rate of chlorine from large to small, and the first rotor flowmeter 10 can display the flow rate of chlorine in real time. At the same time, the nitrogen in the nitrogen buffer tank 2 enters the gas mixer 3 through the second pipeline 11, the nitrogen regulating valve 12 is controlled by the controller to automatically adjust the flow rate of nitrogen from small to large, and the second rotor flowmeter 13 can display the flow rate of nitrogen in real time. In the gas mixer 3, nitrogen and chlorine are fully mixed, and the mixed gas always enters the annular distributor 5 through the third pipeline 14 at a constant pressure, and is discharged from the air hole 5.1 of the annular distributor 5 toward the agitator 7. The discharged bubbles always remain normal, and the pressure will not fluctuate, so as to avoid the formation of back suction; and at the end of the chlorination reaction, the amount of chlorine used is reduced, and excessive polychlorinated impurities will not be formed; in the process of the mixed gas entering the reaction solution, the drive motor 6 is started, and the agitator 7 stirs the reaction solution to dissolve the chlorine in the reaction solution, thereby solving the problem of uneven chlorine flow.

[0019] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A 5-chlorosalicylic acid synthesis system, characterized in that: The invention comprises a chlorine buffer tank, a nitrogen buffer tank, a gas mixer, a reactor and an annular distributor; the annular distributor is fixed horizontally at the bottom of the reactor; the outlet of the chlorine buffer tank is connected with the chlorine inlet of the gas mixer through a first pipeline, a chlorine regulating valve and a first rotor flowmeter are arranged on the first pipeline, the outlet of the nitrogen buffer tank is connected with the nitrogen inlet of the gas mixer through a second pipeline, a nitrogen regulating valve and a second rotor flowmeter are arranged on the second pipeline, the outlet of the gas mixer is connected with a third pipeline, and the third pipeline passes through the top wall of the reactor and is connected with the inlet of the annular distributor.

2. A 5-chlorosalicylic acid synthesis system according to claim 1, characterized in that: A driving motor is externally arranged on the top of the reactor, and an agitator is arranged inside the reactor. The rotating shaft of the agitator passes through the top wall of the reactor and is fixedly connected to the output shaft of the driving motor. The blades of the agitator are placed at the center of the annular distributor.

3. A 5-chlorosalicylic acid synthesis system according to claim 1 or 2, characterized in that: The annular distributor is composed of an annular pipe, the outlet of the third pipeline is connected to the top of the annular pipe, and a plurality of air holes are evenly opened in the inner circle of the annular pipe along the circumferential direction.

4. A 5-chlorosalicylic acid synthesis system according to claim 3, characterized in that: The annular pipeline is a double-layer composite pipe lined with titanium alloy and coated with polytetrafluoroethylene.

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