A continuous water washing reactor for preparing 2,5-dichloronitrobenzene

Abstract

This invention discloses a continuous water washing reactor for preparing 2,5-dichloronitrobenzene, relating to the field of water washing reactor technology. It includes a support frame, a reaction vessel, a separating tank, a water pump, and a processing tank. The reaction vessel is mounted on the upper side of the support frame and includes a sealing cover, a first feeding port, a second feeding port, a stirring motor, stirring blades, a track, a rolling ball, a connecting plate, a rotating rod, and a scraper. This continuous water washing reactor for preparing 2,5-dichloronitrobenzene utilizes the stirring motor to drive the stirring blades and scraper to rotate, allowing the stirring blades to perform the water washing operation while stirring. The scraper can also agitate any residual material on the inner wall of the reaction vessel. The separating tank automatically separates the aqueous solution from the 2,5-dichloronitrobenzene solution, thus achieving continuous upstream and downstream operation of the water washing process, reducing personnel contact, and improving the inherent safety of the 2,5-dichloronitrobenzene preparation process.

Description

Technical Field

[0001] This invention relates to the field of water washing reactor technology, specifically to a continuous water washing reactor for preparing 2,5-dichloronitrobenzene. Background Technology

[0002] 2,5-Dichloronitrobenzene, also known as o-nitro-1,4-dichlorobenzene, 2,5-dichloronitrobenzene, 1,4-dichloro-2-nitrobenzene, nitro-p-dichlorobenzene, o-nitro-1,4-dichlorobenzene, 2-nitro-1,4-dichlorobenzene, 6-nitro-1,4-dichlorobenzene, and p-dichloronitrobenzene, is used as a dye intermediate in ice-dyeing dyes such as bright red GG, red 3GL, and red RC. It is also a nitrogen fertilizer synergist, possessing nitrogen-fixing and fertilizer-retaining properties. The preparation process of 2,5-dichloronitrobenzene involves using a mixed acid of sulfuric acid and nitric acid as a nitrating agent to nitrate p-dichlorobenzene, obtaining the target compound. The product is then obtained through layering, neutralization, and washing. The raw material, p-dichlorobenzene, used in this product is domestically produced, readily available, and has a low cost.

[0003] According to patent number 202022625551.0, a continuous water washing kettle for preparing dichloronitrobenzene is described. After the raw materials are stirred inside the first chamber, the user pulls the piston rod to the right to drive the positioning rod out of the limiting groove. At this time, the positioning rod no longer limits the moving rod. After opening the sealing cover, the rotating rod and stirring blade can be removed from the first chamber. When any problems occur with the stirring device, the user can easily disassemble and replace it. After removal, the inside of the first chamber is hollow, and the user can carefully clean the inside, which improves the overall cleaning efficiency of the water washing kettle. By setting an movable door in the second chamber, the user can clean the impurities filtered by the filter plate to prevent clogging.

[0004] When the above technical solution is used, the raw material is stirred by the rotating rod and stirring blades. After the impurities are filtered by the filter plate, the product solution and the aqueous solution are not separated after production. This makes it easy for the product solution to cool down after being discharged, making it difficult to separate the 2,5-dichloronitrobenzene at room temperature in the subsequent process. Summary of the Invention

[0005] The purpose of this invention is to provide a continuous water washing reactor for preparing 2,5-dichloronitrobenzene, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a continuous water washing reactor for preparing 2,5-dichloronitrobenzene, comprising a support frame, a reaction vessel, a separating tank, a water pump, and a processing tank.

[0007] A reaction vessel is mounted on the upper side of the support frame. The reaction vessel includes a sealing cover, a first feed port, a second feed port, a stirring motor, stirring blades, a track, a rolling ball, a connecting plate, a rotating rod, and a scraper. The top of the reaction vessel is connected to the sealing cover, and the upper side of the sealing cover is symmetrically provided with a first feed port for adding raw materials and a second feed port for heating water. A stirring motor is mounted in the middle of the sealing cover. A level gauge is mounted on the outer side of the reaction vessel. The bottom of the reaction vessel is connected to an electrically controlled valve for discharging the mixed liquid, and a liquid separator is provided below the electrically controlled valve.

[0008] Preferably, the bottom end of the stirring motor is connected to a stirring blade, and a track is fixed on the upper side of the inner wall of the reaction vessel.

[0009] Preferably, a rolling ball is connected to the inner side of the track, and the rolling ball is connected to the connecting plate through the central rotation axis.

[0010] Preferably, the connecting plate is fixed to the rotating rod, and the end of the rotating rod away from the connecting plate is connected to the outer wall of the stirring blade, and a scraper is fixed to the lower side of the two connecting plates.

[0011] Preferably, the liquid distribution tank includes an upper liquid outlet pipe and a lower liquid outlet pipe, the upper liquid outlet pipe being connected to the middle of one side of the liquid distribution tank, and the lower liquid outlet pipe being connected to the bottom of the liquid distribution tank.

[0012] Preferably, the lower end of the lower outlet pipe is connected to the water inlet end of the water pump.

[0013] Preferably, the outlet end of the water pump is connected to a treatment tank, and the treatment tank includes a liquid outlet cylinder, a limiting cover, a motor, a connecting column, a spiral blade, a baffle, a protrusion, a spring, a buffer layer and a water absorption layer, and the liquid outlet cylinder is horizontally fixed at the inner inlet end of the treatment tank.

[0014] A limit cover is welded to the outer wall of the liquid outlet cylinder, and a motor is installed on the side of the treatment tank away from the liquid outlet cylinder.

[0015] Preferably, a connecting post is fixed on the output shaft of the motor, and a spiral blade is fixed at the end of the connecting post away from the output shaft of the motor, the spiral blade being inserted into the inner side of the liquid outlet cylinder;

[0016] The connecting column has a cross-shaped structure, and the central cross-section of the connecting column is a square structure with rounded corners. A baffle is slidably fitted on the outside of the connecting column.

[0017] The inner wall of the baffle is provided with a raised strip, the outer wall of the motor output shaft is provided with a limiting plate, and a spring is connected between the limiting plate and the outer wall of the baffle.

[0018] Preferably, a buffer layer is provided on the lower side of the inner wall of the treatment tank near the baffle, and a water-absorbing layer is provided at the bottom of the buffer layer.

[0019] Preferably, a drain outlet is provided at the lower end of the treatment tank on the side away from the water pump, and an inspection door is embedded in the outside of the treatment tank.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene uses a stirring motor to drive the stirring blades and scraper to rotate, allowing the stirring blades to perform the water washing operation while stirring. The scraper can also mix the residual material on the inner wall of the reaction tank. The separation tank can automatically separate the aqueous solution and the 2,5-dichloronitrobenzene solution, thereby achieving continuous operation of the water washing process, reducing personnel contact, and improving the inherent safety of the 2,5-dichloronitrobenzene preparation process.

[0022] 2. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene uses a water pump to inject the 2,5-dichloronitrobenzene solution from the lower outlet pipe into the outlet cylinder. A motor drives a spiral blade to continuously impact the solution against a baffle. As the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution is continuously injected, it is dispersed by the rotating baffle and the equally angled protrusions. Furthermore, the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution pushes against the baffle, resulting in a fully dispersed mixture that is sprayed out of the outlet cylinder. A processing tank further disperses the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution, facilitating the separation of this small portion of the aqueous solution from the 2,5-dichloronitrobenzene solution.

[0023] 3. In the prepared continuous water washing tank, when the aqueous solution and 2,5-dichloronitrobenzene are sprayed out, the buffer layer can reduce the impact. At the same time, the sprayed solution flows along the gaps in the buffer layer to the absorbent layer, so that the absorbent cotton inside the absorbent layer absorbs a small part of the dispersed aqueous solution, and most of the 2,5-dichloronitrobenzene solution flows along the guide gaps inside the absorbent layer to the drain outlet. The maintenance door is opened periodically, so that the absorbent layer area of ​​the treatment tank is exposed from the side, so that the absorbent cotton used for water removal can be replaced regularly, ensuring that the purity of the 2,5-dichloronitrobenzene solution collected later is high. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the main structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the main cross-sectional structure of the reaction vessel of the present invention;

[0026] Figure 3 This is a top view of the cross-sectional structure of the track of the present invention;

[0027] Figure 4 This is a schematic diagram of the main cross-sectional structure of the processing tank of the present invention;

[0028] Figure 5 This is a schematic diagram of the left-side cross-sectional structure of the shield of the present invention.

[0029] In the diagram: 1. Support frame; 2. Reaction tank; 21. Sealing cover; 22. Feed port 1; 23. Feed port 2; 24. Stirring motor; 25. Stirring blade; 26. Track; 27. Rolling ball; 28. Connecting plate; 29. ​​Rotating rod; 210. Scraper; 3. Level gauge; 4. Electrically controlled valve; 5. Separating tank; 51. Upper outlet pipe; 52. Lower outlet pipe; 6. Water pump; 7. Processing tank; 71. Discharge cylinder; 72. Limit cover; 73. Motor; 74. Connecting column; 75. Spiral blade; 76. Baffle; 77. Protrusion; 78. Spring; 79. Buffer layer; 710. Absorbent layer; 8. Drain outlet; 9. Inspection door. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figures 1-5 This invention provides a technical solution: a continuous water washing kettle for preparing 2,5-dichloronitrobenzene, comprising a support frame 1, a reaction tank 2, a separating tank 5, a water pump 6, and a processing tank 7. The reaction tank 2 is mounted on the upper side of the support frame 1, and the reaction tank 2 has a conical structure. The reaction tank 2 includes a sealing cover 21, a first feeding port 22, a second feeding port 23, a stirring motor 24, a stirring blade 25, a track 26, a rolling ball 27, a connecting plate 28, a rotating rod 29, and a scraper 210. The top of the reaction tank 2 is connected to the sealing cover 21, and the upper side of the sealing cover 21 is symmetrically provided with a first feeding port 22 for adding raw materials and a second feeding port 23 for heating water. The stirring motor 24 is mounted in the middle of the sealing cover 21. A level gauge 3 is mounted on the outer side of the reaction tank 2. The bottom of the reaction tank 2 is connected to an electrically controlled valve 4 for discharging the mixed liquid, and the separating tank 5 is provided below the electrically controlled valve 4.

[0032] The bottom end of the stirring motor 24 is connected to the stirring blade 25. The upper side of the inner wall of the reaction tank 2 is fixed with a track 26, and an annular groove is opened on the inner side of the track 26. A rolling ball 27 is connected to the inner side of the track 26, and the rolling ball 27 is connected to the connecting plate 28 through the central rotating shaft.

[0033] In practice, two sets of connecting plates 28 that are connected to the rotating rod 29 are set on the inner ring of the track 26. Two rolling balls 27 are movably connected to the outside of the connecting plates 28, so as to ensure that the rotating rod 29 drives the scraper 210 to scrape stably along the inner wall of the reaction tank 2 when rotating.

[0034] The connecting plate 28 is fixed to the rotating rod 29, and the end of the rotating rod 29 away from the connecting plate 28 is connected to the outer wall of the stirring blade 25. A scraper 210 is fixed on the lower side of the two connecting plates 28. The scraper 210 is V-shaped, and the outer wall of the scraper 210 is in contact with the inner wall of the reaction vessel 2. The lower side of the scraper 210 is inserted into the bottom of the stirring blade 25.

[0035] In specific implementation, when preparing the material of 2,5-dichloronitrobenzene, 2,5-dichloronitrobenzene is added into the reaction tank 2 through the first feed port 22, and hot water is continuously added into the reaction tank 2 of the water washing kettle through the second feed port 23 in proportion. When the liquid level gauge 3 reaches the preset standard position, the stirring motor 24 is started to drive the stirring blade 25 and the scraper 210 to rotate, so that the stirring blade 25 performs water washing operation in the stirring state, and the scraper 210 can stir the residual material on the inner wall of the reaction tank 2.

[0036] When the scraper 210 rotates, the top two ends of the scraper 210 follow the rotation of the connecting plate 28 and the rotating rod 29, and the two rolling balls 27 on the outside of the connecting plate 28 roll in the annular track 26, ensuring that the continuous water washing kettle has a high-efficiency mixing effect when washing the 2,5-dichloronitrobenzene prepared by water washing.

[0037] The separating tank 5 includes an upper outlet pipe 51 and a lower outlet pipe 52. The upper outlet pipe 51 is connected to the middle of one side of the separating tank 5, and the lower outlet pipe 52 is connected to the bottom of the separating tank 5. A mesh cylinder is installed inside the separating tank 5 and at the upper end of the lower outlet pipe 52, and a stainless steel hollow sealing ball is installed inside the mesh cylinder. The lower end of the lower outlet pipe 52 is connected to the water inlet of the water pump 6. A jacketed steam heating structure is installed on the outside of the separating tank 5 to control the temperature of the liquid in the separating tank 5 between 60-70℃, so that the materials in the tank can be automatically separated into layers according to their specific gravity.

[0038] In practice, since the density of water is 1 g / cm3, and the product prepared by the continuous water washing reactor is 2,5-dichloronitrobenzene, the density of the prepared 2,5-dichloronitrobenzene is about 1.442 g / cm3. Therefore, the density of the stainless steel hollow sealing ball is controlled between 1.2-1.3 g / cm3. When the electrically controlled valve 4 is opened, all the mixture inside the reaction tank 2 is injected into the liquid separator 5.

[0039] Since water and 2,5-dichloronitrobenzene are immiscible, and the density of water is less than that of 2,5-dichloronitrobenzene, water is located in the upper layer of the separating tank 5, and 2,5-dichloronitrobenzene is located in the lower layer of the separating tank 5. First, a stainless steel hollow sealing ball with a density controlled between 1.2-1.3 g / cm3 is placed in the 2,5-dichloronitrobenzene solution, causing the sealing ball to float. This allows the 2,5-dichloronitrobenzene solution to flow along the lower outlet pipe 52 to the position of the water pump 6. When the sealing ball comes into contact with the aqueous solution, it falls and blocks the upper port of the lower outlet pipe 52. At this time, by turning on the siphon pump of the upper outlet pipe 51, the aqueous solution can be extracted from the upper outlet pipe 51.

[0040] The outlet end of the water pump 6 is connected to a treatment tank 7, which includes an outlet cylinder 71, a limiting cover 72, a motor 73, a connecting column 74, a spiral blade 75, a baffle 76, a protrusion 77, a spring 78, a buffer layer 79, and a water absorption layer 710. The outlet cylinder 71 is horizontally fixed to the inner inlet end of the treatment tank 7. The limiting cover 72 is welded to the outer wall of the outlet cylinder 71. The motor 73 is installed on the side of the treatment tank 7 away from the outlet cylinder 71. The connecting column 74 is fixed on the output shaft of the motor 73, and the spiral blade 75 is fixed at the end of the connecting column 74 away from the output shaft of the motor 73. The spiral blade 75 is inserted into the inner side of the outlet cylinder 71. The output shaft of the motor 73 and the outlet cylinder 71 are on the same axis.

[0041] In practice, by starting the water pump 6, the 2,5-dichloronitrobenzene solution in the lower outlet pipe 52 is injected into the outlet cylinder 71, and the motor 73 is started to drive the spiral blade 75 to continuously impact the solution against the baffle 76.

[0042] The connecting post 74 has a cross-shaped structure, and the central cross section of the connecting post 74 is a square structure with rounded corners. A cover 76 is slidably sleeved on the outer side of the connecting post 74. The inner wall of the cover 76 is provided with protruding strips 77, and the protruding strips 77 are distributed at equal angles. The outer wall of the output shaft of the motor 73 is provided with a limit plate, and a spring 78 is connected between the limit plate and the outer wall of the cover 76. The cover 76 and the connecting post 74 form a sliding structure through the spring 78.

[0043] In practice, as the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution is continuously injected, it is dispersed by the rotating baffle 76 and the equally angled protrusions 77. Furthermore, the continuous injection of the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution pushes against the baffle 76, causing it to slide along the connecting column 74. This gradually increases the gap between the baffle 76 and the limiting cover 72 as the baffle 76 compresses the spring 78. The fully dispersed mixed solution is then sprayed out from the outlet cylinder 71. After a portion of the solution is sprayed out, the pressure of the mixed solution is less than the thrust of the spring 78. At this point, most of the mixed solution is sealed between the outlet cylinder 71, the limiting cover 72, and the baffle 76. This disperses the 2,5-dichloronitrobenzene solution with a small amount of aqueous solution collected in the treatment tank 7, thereby reducing the pressure on the absorbent layer 710 when it absorbs water.

[0044] A buffer layer 79 is provided on the lower side of the inner wall of the treatment tank 7 near the baffle 76, and a water-absorbing layer 710 is provided at the bottom of the buffer layer 79. The buffer layer 79 is composed of V-shaped guide plates that are evenly distributed, and the opening direction of the V-shaped guide plates is horizontal. The water-absorbing layer 710 is composed of a support frame, water-absorbing cotton and guide gaps, and the support frame is used to support and place the water-absorbing cotton.

[0045] In practice, the sprayed solution is buffered by the buffer layer 79 to reduce the impact, so that the sprayed solution flows along the gaps in the buffer layer 79 to the absorbent layer 710. The absorbent cotton inside the absorbent layer 710 absorbs a small portion of the dispersed aqueous solution, and most of the 2,5-dichloronitrobenzene solution flows along the guide gaps inside the absorbent layer 710 to the drain outlet 8 for discharge.

[0046] A drain outlet 8 is provided at the lower end of the treatment tank 7 on the side away from the water pump 6, and an inspection door 9 is embedded in the outside of the treatment tank 7.

[0047] In practice, by periodically opening the inspection door 9, the area of ​​the water-absorbing layer 710 of the treatment tank 7 is exposed from the side, so that the water-absorbing cotton used for water removal can be replaced periodically, ensuring that the purity of the 2,5-dichloronitrobenzene solution collected later is high.

[0048] In summary, using a mixed acid of sulfuric acid and nitric acid as a nitrating agent, dichlorobenzene is nitrated to obtain the target product. Then, through layering, neutralization, and water washing, the 2,5-dichloronitrobenzene product is obtained. For this purpose, 2,5-dichloronitrobenzene is added into the reaction tank 2 through the first feed port 22, and hot water is continuously added into the reaction tank 2 of the water washing vessel through the second feed port 23 in proportion. The two solutions with different densities and immiscibility are automatically separated by the separating tank 5, and the aqueous solution with a small amount is dispersed by the treatment tank 7, so that the aqueous solution is absorbed by the water absorption layer 710 when it is sprayed out, ensuring that a high-purity 2,5-dichloronitrobenzene solution can be discharged from the drain port 8. The contents not described in detail in this description are prior art known to those skilled in the art.

[0049] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A continuous water washing vessel for preparing 2,5-dichloronitrobenzene, comprising a support frame (1), a reaction vessel (2), a separating tank (5), a water pump (6), and a processing tank (7), characterized in that: The upper side of the support frame (1) is equipped with a reaction tank (2). The reaction tank (2) includes a sealing cover (21), a first feeding port (22), a second feeding port (23), a stirring motor (24), a stirring blade (25), a track (26), a rolling ball (27), a connecting plate (28), a rotating rod (29), and a scraper (210). The top of the reaction tank (2) is connected to the sealing cover (21), and the upper side of the sealing cover (21) is symmetrically provided with a first feeding port (22) for adding raw materials and a second feeding port (23) for heating water. The middle part of the sealing cover (21) is equipped with a stirring motor (24). The outer side of the reaction tank (2) is equipped with a level gauge (3). The bottom of the reaction tank (2) is connected to an electrically controlled valve (4) for discharging the mixed liquid. The lower side of the electrically controlled valve (4) is provided with a liquid separator (5). The outlet end of the water pump (6) is connected to the treatment tank (7), and the treatment tank (7) includes a liquid outlet cylinder (71), a limiting cover (72), a motor (73), a connecting column (74), a spiral blade (75), a baffle (76), a protrusion (77), a spring (78), a buffer layer (79), and a water absorption layer (710). The liquid outlet cylinder (71) is horizontally fixed at the inner inlet end of the treatment tank (7). The outer wall of the liquid outlet cylinder (71) is welded with a limit cover (72), and a motor (73) is installed on the side of the treatment tank (7) away from the liquid outlet cylinder (71). A connecting column (74) is fixed on the output shaft of the motor (73), and a spiral blade (75) is fixed at the end of the connecting column (74) away from the output shaft of the motor (73). The spiral blade (75) is inserted into the inside of the liquid outlet cylinder (71). The connecting column (74) has a "+" shaped structure, and the central cross section of the connecting column (74) is a square structure with rounded corners. A cover (76) is slidably sleeved on the outside of the connecting column (74). The inner wall of the baffle (76) is provided with a protrusion (77), the outer wall of the output shaft of the motor (73) is provided with a limit plate, and a spring (78) is connected between the limit plate and the outer wall of the baffle (76). A buffer layer (79) is provided on the inner wall of the treatment tank (7) near the lower side of the baffle (76), and a water-absorbing layer (710) is provided at the bottom of the buffer layer (79).

2. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 1, characterized in that: The bottom end of the stirring motor (24) is connected to the stirring blade (25), and the upper side of the inner wall of the reaction vessel (2) is fixed with a track (26).

3. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 2, characterized in that: The inner side of the track (26) is connected to a rolling ball (27), and the rolling ball (27) is connected to the connecting plate (28) through the central rotating shaft.

4. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 3, characterized in that: The connecting plate (28) is fixed to the rotating rod (29), and the end of the rotating rod (29) away from the connecting plate (28) is connected to the outer wall of the stirring blade (25). A scraper (210) is fixed on the lower side of the two connecting plates (28).

5. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 1, characterized in that: The liquid distribution tank (5) includes an upper liquid outlet pipe (51) and a lower liquid outlet pipe (52). The upper liquid outlet pipe (51) is connected to the middle of one side of the liquid distribution tank (5), and the lower liquid outlet pipe (52) is connected to the bottom of the liquid distribution tank (5).

6. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 5, characterized in that: The lower end of the lower outlet pipe (52) is connected to the water inlet of the water pump (6).

7. The continuous water washing reactor for preparing 2,5-dichloronitrobenzene according to claim 1, characterized in that: The lower end of the treatment tank (7) away from the water pump (6) is provided with a drain outlet (8), and an inspection door (9) is embedded in the outside of the treatment tank (7).

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