A continuous flow reactor for synthesis of salicylonitrile

Abstract

The utility model discloses a continuous flow reactor for salicylanilide synthesis, including reactor body, its top is equipped with solvent, liquid alkali and salicylamide feed port, bottom is equipped with salicylanilide product discharge gate. Inside from top to bottom is in turn interval and arranges four liquid phase distribution board, and there is salicylamide cloth material ware above liquid phase first distribution board, and its below is connected with a plurality of even distribution's material outflow pipe and first liquid phase nozzle structure, and the subsequent distribution board below also is connected corresponding nozzle component respectively. The upper middle and lower positions of reactor side wall are equipped with three dimethyl ether feed port, and the corresponding dimethyl ether vaporizer, two layers of dimethyl ether distribution board are arranged at each feed port. In the reactor reaction area, at the same height as each dimethyl ether feed port, gas phase impinging stream and liquid phase impinging stream board are arranged respectively, the gas phase impinging stream board is arranged vertically or with a small angle, and the liquid phase impinging stream board is arranged horizontally or with a small angle. The utility model effectively solves the problem of uneven gas-liquid distribution and low mass transfer efficiency of the existing salicylanilide synthesis reactor.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, and in particular to a continuous flow reactor for the synthesis of salicylates. Background Technology

[0002] Salicylic acid nitrile, as an important organic synthesis intermediate, has wide and crucial applications in many chemical fields such as pharmaceuticals, pesticides, and dyes. The efficiency and quality of its synthesis reaction directly affect the performance and cost of downstream products. Therefore, developing efficient, stable, and safe salicylic acid nitrile synthesis processes and reactors is of significant practical importance.

[0003] In traditional salicylaniline synthesis reactors, due to inadequate internal structural design, the mixing process relies primarily on natural diffusion and simple stirring. This mixing method makes it difficult for reactants to achieve sufficient and uniform contact in a short time, resulting in a slow reaction rate, prolonged reaction time, and consequently reduced efficiency of the entire synthesis process. Phosgene, as a key raw material in the salicylaniline synthesis reaction, has a crucial impact on the reaction results due to its uniform distribution within the reactor. However, the single-stage feeding method used in traditional reactors makes it difficult for phosgene to disperse rapidly and uniformly throughout the reaction system after entering the reactor. Phosgene often forms a locally high concentration area near the inlet, while the concentration is lower in areas far from the inlet. This uneven phosgene distribution not only leads to incomplete reaction and reduced product yield but may also trigger a series of side reactions, increasing the impurity content of the product and affecting its purity and quality.

[0004] In summary, existing salicylates synthesis reactors still have many shortcomings in enhancing the mixing, mass transfer, and reaction of gas-liquid multiphase flow systems, and cannot meet the requirements of industrial production for high efficiency, stability, and environmental protection. Utility Model Content

[0005] To address the problems existing in the prior art, this utility model aims to provide a continuous flow reactor for salicylates synthesis, thereby solving the problems of uneven gas-liquid distribution and low mass transfer efficiency in existing salicylates synthesis reactors.

[0006] To achieve the above objectives, this utility model proposes a continuous flow reactor for the synthesis of salicylates, comprising a reactor body, wherein the top of the reactor body is provided with a solvent inlet, a liquid alkali inlet and a salicylamide inlet, and the bottom of the reactor body is provided with a salicylates product outlet.

[0007] The reactor body is equipped with a first liquid phase distribution plate, a second liquid phase distribution plate, a third liquid phase distribution plate and a fourth liquid phase distribution plate arranged sequentially from top to bottom;

[0008] A salicylic amide feeder is arranged above the first liquid phase distribution plate. The solvent inlet and the salicylic amide feed inlet both extend into the interior of the reactor body and are connected to the salicylic amide feeder. The salicylic amide feeder is connected downward to multiple material outlet pipes. Each material outlet pipe is evenly distributed along the circumference and its end is connected to a first liquid phase nozzle structure. Several second liquid phase nozzle components are connected below the first liquid phase distribution plate. Several third liquid phase nozzle components are connected below the second liquid phase distribution plate. Several fourth nozzle components are connected below the third liquid phase distribution plate.

[0009] The reactor body has phosgene inlets evenly distributed at three positions on its side wall: upper, middle, and lower. From top to bottom, these are the upper phosgene inlet, the middle phosgene inlet, and the lower phosgene inlet. The upper phosgene inlet is located between the first liquid phase distribution plate and the second liquid phase distribution plate. The middle phosgene inlet is located between the second liquid phase distribution plate and the third liquid phase distribution plate. The lower phosgene inlet is located between the third liquid phase distribution plate and the fourth liquid phase distribution plate.

[0010] Inside the reactor body, corresponding to each phosgene inlet, there is a phosgene vaporizer, a first phosgene distribution plate, and a second phosgene distribution plate. The phosgene vaporizer is arranged on the inner wall of the reactor body at the same height as the phosgene inlet and is connected to the corresponding phosgene inlet. The first phosgene distribution plate and the second phosgene distribution plate are arranged radially from the outside to the inside. The first phosgene distribution plate is connected to the phosgene vaporizer, and the second phosgene distribution plate is connected to the first phosgene distribution plate. The inner side of the second phosgene distribution plate is the reactor reaction zone.

[0011] The reactor reaction zone is provided with, from top to bottom, upper gas phase impact plates, middle gas phase impact plates, and lower gas phase impact plates, as well as upper liquid phase impact plates, middle liquid phase impact plates, and lower liquid phase impact plates. The upper and middle gas phase impact plates are arranged at the same height as the upper phosgene inlet, the middle gas phase impact plates are arranged at the same height as the middle phosgene inlet, and the lower gas phase impact plates are arranged at the same height as the lower phosgene inlet. The upper, middle, and lower gas phase impact plates are arranged vertically or at an angle of 10 degrees away from the vertical direction, while the upper, middle, and lower liquid phase impact plates are arranged horizontally or at an angle of 10 degrees away from the horizontal direction.

[0012] In the above scheme: the solvent inlet is a toluene inlet, the top of the reactor body is provided with two salicylamide inlets, and the bottom of the reactor body is provided with 2 to 4 salicylaniline product outlets, which are used to discharge a mixed solution of salicylaniline, solvent, and liquid alkali.

[0013] In the above scheme, there are 12 to 24 first liquid phase nozzle structures. The design of multiple first liquid phase nozzle structures evenly distributed around the circumference allows salicylic acid amide and solvent to be sprayed into the reactor at a uniform flow rate and distribution, achieving preliminary uniform dispersion.

[0014] In the above scheme: both the first phosgene distribution plate and the second phosgene distribution plate are composed of 3 to 6 sector-shaped cylinders, which are combined to form a cylindrical structure. Each sector-shaped cylinder is snap-fitted together as a single unit, allowing for independent disassembly and convenient maintenance.

[0015] In the above scheme: the first phosgene distribution plate and the second phosgene distribution plate are both fixed to the inner wall of the reactor body by a bracket, and the arrangement height of both is flush with the corresponding phosgene inlet. The fan-shaped cylinder adopts a through-type design with openings at both ends. The opening range of the second phosgene distribution plate is larger than that of the first phosgene distribution plate, and the opening range of the second phosgene distribution plate completely covers the opening range of the first phosgene distribution plate, forming a unique structure of "staged flow guidance + secondary diffusion", which is conducive to optimizing the flow field, making the gas-liquid reaction more complete, and increasing the mass transfer effect.

[0016] In the above scheme: the first, second, third, and fourth liquid phase distribution plates are all perforated baffles. The perforation rate of the first liquid phase distribution plate is 15%~20%, the second liquid phase distribution plate is 10%~15%, the third liquid phase distribution plate is 9%~12%, and the fourth liquid phase distribution plate is 16%~25%, achieving gradient diffusion of the reaction liquid and promoting uniform distribution. Corresponding liquid phase nozzle structures are connected below the perforations of the liquid phase distribution plates.

[0017] In the above scheme: 6-12 impactor plates are evenly distributed along the circumference of the upper, middle, and lower gas phases; 3-6 impactor plates are evenly distributed along the circumference of the upper, middle, and lower liquid phases. All impactor plates are fixed to the inner wall of the reactor body by supports. The arranged gas phase impactor plates enhance the interaction between vaporized phosgene and the gas phase impactor flow, increase the turbulence of the gas phase, and strengthen the mixing and mass transfer effect between the gas and liquid phases. High-intensity turbulent mixing occurs between the gas and liquid phases in the impactor plate region, which is beneficial for significantly improving the reaction rate and conversion efficiency.

[0018] The beneficial effects of this invention are: 1. Multi-stage liquid phase distribution and nozzle design, multi-stage gas-liquid distribution and impingement flow enhancement ensure thorough mixing of reactants, increase gas-liquid contact area, optimize mass transfer path, accelerate reaction speed, and improve conversion rate and selectivity. 2. Multi-stage feeding and zone control allow for precise control of feed rate and time according to reaction stage, and independent adjustment of parameters in each zone; the continuous flow reaction mode avoids batch differences, reduces human influence, and ensures stable product quality. 3. High-efficiency reaction increases production capacity, processing more reactants in the same amount of time; the integrated design is compact, reducing equipment investment, labor and operation and maintenance costs, and reducing raw material and energy consumption; continuous production reduces intermediate links, avoids pollution and errors, achieves efficient and smooth operation, and improves production continuity and stability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] Figure 2 This is a schematic diagram of the structure of the first phosgene distribution plate and the second phosgene distribution plate.

[0021] Figure 3 This is a schematic diagram of the layout of the salicylic acid amide feeder and the first liquid phase nozzle structure. Detailed Implementation

[0022] like Figure 1 As shown in Figure 3, a continuous flow reactor for the synthesis of salicylates is mainly composed of reactor body 1.

[0023] The top of reactor body 1 is equipped with a solvent inlet 2, a liquid alkali inlet 3, and a salicylamide inlet 4, while the bottom of reactor body 1 is equipped with a salicylate product outlet 5. Specifically, solvent inlet 2 is a toluene inlet, the top of reactor body 1 has two salicylamide inlets 4, and the bottom of reactor body 1 has 2 to 4 salicylate product outlets 5, which are used to discharge a mixed solution of salicylate, solvent, and liquid alkali.

[0024] Inside the reactor body 1, a first liquid phase distribution plate 6, a second liquid phase distribution plate 7, a third liquid phase distribution plate 8, and a fourth liquid phase distribution plate 9 are arranged sequentially from top to bottom.

[0025] A salicylic acid amide distributor 10 is arranged above the first liquid phase distribution plate 6. The solvent inlet 2 and the salicylic acid amide inlet 4 both extend into the interior of the reactor body 1 and are connected to the salicylic acid amide distributor 10. The salicylic acid amide distributor 10 is connected downward to multiple material outlet pipes, which are evenly distributed along the circumference and are all connected to the first liquid phase nozzle structure 11 at their ends.

[0026] There are 12 to 24 first liquid phase nozzle structures 11. The design of multiple first liquid phase nozzle structures 11 evenly distributed around the circumference allows salicylic acid amide and solvent to be sprayed into the reactor at a uniform flow rate and distribution, achieving preliminary uniform dispersion.

[0027] Several liquid phase second nozzle components 12 are connected below the first liquid phase distribution plate 6, several liquid phase third nozzle components 13 are connected below the second liquid phase distribution plate 7, and several fourth nozzle components 14 are connected below the third liquid phase distribution plate 8.

[0028] The reactor body 1 has phosgene inlets evenly distributed at three positions on its side wall: upper, middle, and lower. From top to bottom, these are the upper phosgene inlet 15, the middle phosgene inlet 16, and the lower phosgene inlet 17. The upper phosgene inlet 15 is located between the first liquid phase distribution plate 6 and the second liquid phase distribution plate 7. The middle phosgene inlet 16 is located between the second liquid phase distribution plate 7 and the third liquid phase distribution plate 8. The lower phosgene inlet 17 is located between the third liquid phase distribution plate 8 and the fourth liquid phase distribution plate 9.

[0029] Inside the reactor body 1, corresponding to each phosgene inlet, there is also a phosgene vaporizer 18, a first phosgene distribution plate 19, and a second phosgene distribution plate 20. The phosgene vaporizer 18 is arranged on the inner wall of the reactor body 1 at the same height as the phosgene inlet and is connected to the corresponding phosgene inlet. The first phosgene distribution plate 19 and the second phosgene distribution plate 20 are arranged radially from the outside to the inside. The first phosgene distribution plate 19 is connected to the phosgene vaporizer 18, and the second phosgene distribution plate 20 is connected to the first phosgene distribution plate 19. The inner side of the second phosgene distribution plate 20 is the reactor reaction zone.

[0030] Both the first phosgene distribution plate 19 and the second phosgene distribution plate 20 are composed of 3 to 6 sector-shaped cylinders, which are combined to form a cylindrical structure. Each sector-shaped cylinder is snap-fitted together as a whole, and can be disassembled independently for easy maintenance.

[0031] Both the first phosgene distribution plate 19 and the second phosgene distribution plate 20 are fixed to the inner wall of the reactor body 1 by a bracket, and their arrangement height is flush with the corresponding phosgene inlet. The fan-shaped cylinder adopts a through-type design with openings at both ends. The opening range of the second phosgene distribution plate 20 is larger than that of the first phosgene distribution plate 19, and the opening range of the second phosgene distribution plate 20 completely covers the opening range of the first phosgene distribution plate 19, forming a unique structure of "staged flow guidance + secondary diffusion", which is conducive to optimizing the flow field, making the gas-liquid reaction more complete, and increasing the mass transfer effect.

[0032] Within the reactor reaction zone, from top to bottom, there are sequentially arranged upper gas phase impact plates 21, middle gas phase impact plates 22, and lower gas phase impact plates 23. Also from top to bottom, there are upper liquid phase impact plates 24, middle liquid phase impact plates 25, and lower liquid phase impact plates 26. The arrangement heights of the upper gas phase impact plates 21 and 24 are consistent with the arrangement height of the upper phosgene inlet 15. The arrangement heights of the middle gas phase impact plates 22 and 25 are consistent with the arrangement height of the middle phosgene inlet 16. The arrangement heights of the lower gas phase impact plates 23 and 26 are consistent with the arrangement height of the lower phosgene inlet 17. The upper gas phase impact plate 21, the middle gas phase impact plate 22, and the lower gas phase impact plate 23 are all arranged vertically or within a 10-degree inclination angle from the vertical direction. The upper liquid phase impact plate 24, the middle liquid phase impact plate 25, and the lower liquid phase impact plate 26 are all arranged horizontally or within a 10-degree inclination angle from the horizontal direction.

[0033] The first liquid phase distribution plate 6, the second liquid phase distribution plate 7, the third liquid phase distribution plate 8, and the fourth liquid phase distribution plate 9 are all perforated baffles. The perforation rate of the first liquid phase distribution plate 6 is 15%~20%, that of the second liquid phase distribution plate 7 is 10%~15%, that of the third liquid phase distribution plate 8 is 9%~12%, and that of the fourth liquid phase distribution plate 9 is 16%~25%, achieving gradient diffusion of the reaction liquid and promoting uniform distribution. Corresponding liquid phase nozzle structures are connected below the perforations of the liquid phase distribution plates.

[0034] Six to twelve impactor plates are evenly distributed along the circumference of the upper gas phase impingement plate 21, middle gas phase impingement plate 22, and lower gas phase impingement plate 23. Three to six impactor plates are evenly distributed along the circumference of the liquid phase impingement plate 24, middle liquid phase impingement plate 25, and lower liquid phase impingement plate 26. All three plates are fixed to the inner wall of the reactor body 1 by supports. The arranged gas phase impingement plates enhance the interaction between vaporized phosgene and the gas phase impingement flow, increase the turbulence of the gas phase, and strengthen the mixing and mass transfer effect between the gas and liquid phases. High-intensity turbulent mixing occurs between the gas and liquid phases in the impingement plate region, which is beneficial for significantly improving the reaction rate and conversion efficiency.

Claims

1. A continuous flow reactor for the synthesis of salicylates, comprising a reactor body (1), characterized in that: The top of the reactor body (1) is provided with a solvent inlet (2), a liquid alkali inlet (3) and a salicylic amide inlet (4), and the bottom of the reactor body (1) is provided with a salicylic nitrile product outlet (5). The reactor body (1) is provided with a first liquid phase distribution plate (6), a second liquid phase distribution plate (7), a third liquid phase distribution plate (8) and a fourth liquid phase distribution plate (9) arranged sequentially from top to bottom. A salicylic amide feeder (10) is arranged above the first liquid phase distribution plate (6). The solvent inlet (2) and the salicylic amide feed inlet (4) both extend into the interior of the reactor body (1) and are connected to the salicylic amide feeder (10). The salicylic amide feeder (10) is connected downward to multiple material outlet pipes. Each material outlet pipe is evenly distributed along the circumference and its end is connected to a first liquid phase nozzle structure (11). Several second liquid phase nozzle components (12) are connected below the first liquid phase distribution plate (6). Several third liquid phase nozzle components (13) are connected below the second liquid phase distribution plate (7). Several fourth nozzle components (14) are connected below the third liquid phase distribution plate (8). The reactor body (1) has phosgene inlets evenly distributed at three positions on its side wall: upper, middle and lower. From top to bottom, they are the upper phosgene inlet (15), the middle phosgene inlet (16) and the lower phosgene inlet (17). The upper phosgene inlet (15) is arranged between the first liquid phase distribution plate (6) and the second liquid phase distribution plate (7). The middle phosgene inlet (16) is arranged between the second liquid phase distribution plate (7) and the third liquid phase distribution plate (8). The lower phosgene inlet (17) is arranged between the third liquid phase distribution plate (8) and the fourth liquid phase distribution plate (9). Inside the reactor body (1), a phosgene vaporizer (18), a first phosgene distribution plate (19), and a second phosgene distribution plate (20) are arranged for each phosgene inlet. The phosgene vaporizer (18) is arranged on the inner wall of the reactor body (1) at the same height as the phosgene inlet and is connected to the corresponding phosgene inlet. The first phosgene distribution plate (19) and the second phosgene distribution plate (20) are arranged radially from the outside to the inside. The first phosgene distribution plate (19) is connected to the phosgene vaporizer (18), and the second phosgene distribution plate (20) is connected to the first phosgene distribution plate (19). The inner side of the second phosgene distribution plate (20) is the reactor reaction zone. The reactor reaction zone is provided with, from top to bottom, a gas phase upper impactor plate (21), a gas phase middle impactor plate (22), and a gas phase lower impactor plate (23). It is also provided with, from top to bottom, a liquid phase upper impactor plate (24), a liquid phase middle impactor plate (25), and a liquid phase lower impactor plate (26). The arrangement heights of the gas phase upper impactor plate (21) and the liquid phase upper impactor plate (24) are consistent with the arrangement height of the phosgene upper inlet (15). The arrangement heights of the gas phase middle impactor plate (22) and the liquid phase middle impactor plate (25) are consistent with the arrangement height of the phosgene upper inlet (15). The gas inlet (16) is arranged at the same height, and the gas phase lower impact flow plate (23) and the liquid phase lower impact flow plate (26) are arranged at the same height as the phosgene lower inlet (17). The gas phase upper impact flow plate (21), gas phase middle impact flow plate (22) and gas phase lower impact flow plate (23) are all arranged vertically or within a 10-degree inclination angle from the vertical direction. The liquid phase upper impact flow plate (24), liquid phase middle impact flow plate (25) and liquid phase lower impact flow plate (26) are all arranged horizontally or within a 10-degree inclination angle from the horizontal direction.

2. The continuous flow reactor for the synthesis of salicylates according to claim 1, characterized in that: The solvent inlet (2) is a toluene inlet, and the top of the reactor body (1) is provided with two salicylamide inlets (4), and the bottom of the reactor body (1) is provided with 2 to 4 salicylnitrile product outlets (5).

3. The continuous flow reactor for the synthesis of salicylates according to claim 1, characterized in that: The first liquid phase nozzle structure (11) has 12 to 24 nozzles.

4. The continuous flow reactor for the synthesis of salicylates according to claim 1, characterized in that: The first phosgene distribution plate (19) and the second phosgene distribution plate (20) are both composed of 3 to 6 fan-shaped cylinders, which are combined to form a cylindrical structure.

5. The continuous flow reactor for the synthesis of salicylates according to claim 4, characterized in that: The first phosgene distribution plate (19) and the second phosgene distribution plate (20) are both fixed to the inner wall of the reactor body (1) by a bracket, and the arrangement height of both is flush with the corresponding phosgene inlet. The fan-shaped cylinder adopts a through-type design with openings at both ends. The opening range of the second phosgene distribution plate (20) is larger than the opening range of the first phosgene distribution plate (19), and the opening range of the second phosgene distribution plate (20) completely covers the opening range of the first phosgene distribution plate (19).

6. The continuous flow reactor for the synthesis of salicylates according to claim 1, characterized in that: The first liquid phase distribution plate (6), the second liquid phase distribution plate (7), the third liquid phase distribution plate (8), and the fourth liquid phase distribution plate (9) are all perforated partitions. The perforation rate of the first liquid phase distribution plate (6) is 15%~20%, the perforation rate of the second liquid phase distribution plate (7) is 10%~15%, the perforation rate of the third liquid phase distribution plate (8) is 9%~12%, and the perforation rate of the fourth liquid phase distribution plate (9) is 16%~25%.

7. The continuous flow reactor for the synthesis of salicylates according to claim 1, characterized in that: The gas phase upper impact flow plate (21), gas phase middle impact flow plate (22) and gas phase lower impact flow plate (23) are all evenly arranged with 6 to 12 pieces along the circumference. The liquid phase upper impact flow plate (24), liquid phase middle impact flow plate (25) and liquid phase lower impact flow plate (26) are all evenly arranged with 3 to 6 pieces along the circumference. The gas phase upper impact flow plate (21), gas phase middle impact flow plate (22), gas phase lower impact flow plate (23), liquid phase upper impact flow plate (24), liquid phase middle impact flow plate (25) and liquid phase lower impact flow plate (26) are all fixed to the inner wall of the reactor body (1) by a bracket.

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