A continuous photochlorination apparatus for toluene side chain and a method of use

Abstract

The application discloses a kind of toluene side chain continuous photochlorination reaction device and use method, belong to chemical production equipment technical field, including reaction kettle, light transmission sleeve and ultraviolet light source;Rotary rod of hollow structure is rotationally arranged in the inner chamber of reaction kettle, and stirring rod of hollow structure is evenly inserted on the lateral wall of rotary rod, and the inner chamber of stirring rod is interconnected with the inner chamber of rotary rod;Reaction kettle is provided with gas supply mechanism for rotary rod inner chamber gas supply;The scheme is driven by stirring rod high-speed rotation, in the stirring rod rotation process, the backwater surface of stirring rod generates water vortex with suction, gas bubble will be sucked into vortex, and large gas bubble in vortex will be torn and broken, and by the cooperation of high-speed rotating sweep-hole scraping plate and stationary baffle, the gas bubble being cut across bubble-breaking hole is cut;When the gas bubble that crosses bubble-breaking hole moves along the lower surface of baffle and crosses the gap between burrs, the gas bubble with volume greater than the gap between burrs will be hindered by the side wall of burr and be broken again.

Description

Technical Field

[0001] This invention relates to the field of chemical production equipment technology, and more specifically, to a continuous photochlorination reactor for toluene side chains and its method of use. Background Technology

[0002] Toluene side-chain chlorination products (such as benzyl chloride, benzyl dichloride, and trichlorotoluene) are extremely important intermediates in fine chemicals and organic synthesis, widely used in pharmaceuticals, pesticides, fragrances, dyes, and synthetic resins. Industrially, these products are mainly produced through a free radical chain substitution reaction between toluene and chlorine under ultraviolet light irradiation. Because photochlorination does not require the introduction of chemical initiators into the reaction system, avoiding contamination, and the reaction conditions are relatively mild, it is widely used in industrial production.

[0003] Currently, most industrial photochlorination reactions of toluene side chains are carried out using traditional batch reactors or simple bubble column reactors. In these conventional devices, liquid toluene serves as the continuous phase, chlorine gas is typically introduced into the reaction solution through a common bubble tube or simple gas distribution plate at the bottom, and an ultraviolet light source (such as a high-pressure / medium-pressure mercury lamp) is inserted into the reaction solution through a sealed quartz cold trap sleeve to provide the ultraviolet light energy required to initiate the reaction.

[0004] However, in practical industrial scale-up and continuous production applications, existing photochlorination reactors have revealed serious technical bottlenecks in gas-liquid mixing and mass transfer, specifically manifested in the following ways: Large bubble size and low gas-liquid mass transfer efficiency result in a high chlorine escape rate. The rate of the photochemical reaction is largely limited by the mass transfer rate from the reactant gas (chlorine) to the liquid phase (toluene). Existing reaction devices typically rely on conventional bubbling for gas-liquid mixing. This method produces low gas dispersion, large chlorine bubble size, and rapid rise, resulting in a small surface area for gas-liquid contact and extremely short bubble residence time in the reaction liquid. Limited by this inefficient interphase mass transfer process, a large amount of free chlorine gas fails to dissolve and participate in the photochemical reaction in time, instead directly penetrating the reaction liquid layer and escaping to the surface. This high escape rate not only causes significant raw material waste and substantially increases production costs, but also places a huge processing load and environmental safety pressure on downstream tail gas condensation, absorption, and acid production systems due to the high concentration of chlorine-containing tail gas.

[0005] Therefore, a continuous photochlorination reactor for toluene side chains and its usage method are proposed. Summary of the Invention

[0006] To address the problems existing in the prior art, the purpose of this invention is to provide a continuous photochlorination reaction device and method for toluene side chains, which can improve reaction efficiency by reducing the volume of bubbles.

[0007] To solve the above problems, the present invention adopts the following technical solution.

[0008] A continuous photochlorination reactor for toluene side chains and its method of use, comprising a reaction vessel, a light-transmitting sleeve and an ultraviolet light source; A hollow rotating rod is rotatably installed inside the reactor cavity, and hollow stirring rods are evenly inserted into the side wall of the rotating rod, with the inner cavity of the stirring rods communicating with the inner cavity of the rotating rod. The reactor is equipped with a gas supply mechanism to supply gas to the inner cavity of the rotating rod; A partition is horizontally fixed in the inner cavity of the reactor. A rotating rod passes through the partition and rotates with it. Stirring rods are distributed below the partition. Several air distribution holes are provided on the side wall of the stirring rod. The air distribution holes are located on the back water side in the direction of rotation of the stirring rod, and the channels of the air distribution holes are in the shape of a funnel mouth that gradually expands from the inside to the outside. The partition plate has evenly distributed bubble-breaking holes on its surface; a radially extending sweeping scraper is fixed on the side wall of the rotating rod. The upper edge of the sweeping scraper is slidably fitted with the lower surface of the partition plate, and the sweeping scraper rotates with the rotating rod and sweeps across the area below the bubble-breaking holes.

[0009] Furthermore, the upper surface of the baffle is fixedly provided with several inclined baffles, each baffle being arranged in a circular array around the rotating rod; the lower surface of the baffle is provided with bubble-breaking burrs.

[0010] Furthermore, the lower surface of the baffle plate is a concave gas storage arc surface; Furthermore, the bubble-breaking burr array is distributed within the gas storage arc surface.

[0011] Furthermore, the upper surface of the partition is coated with an ultraviolet light reflective layer, and the ultraviolet light reflective layer faces upward directly onto the gas storage arc surface of the baffle plate.

[0012] Furthermore, the gas supply mechanism includes a sleeve that is fixedly installed inside the reactor; The hollow rotating rod is rotatably inserted through the sleeve, and the two ends of the sleeve are slidably sealed with the outer wall of the rotating rod; An air inlet is provided on the side wall of the section of the rotating rod covered by the sleeve, which communicates with the inner cavity of the sleeve. An air inlet pipe is installed on the side wall of the reactor, with one end connected to the inner cavity of the sleeve. The end of the air inlet pipe away from the sleeve is connected to an external air source.

[0013] Furthermore, a first cooling chamber is provided inside the baffle plate, and a second cooling chamber is provided inside the partition plate; The first cooling chamber and the second cooling chamber are connected by a guide pipe; A cooling medium output pipe and a cooling medium input pipe are respectively inserted into the first cooling chamber and the second cooling chamber. The end of the cooling medium input pipe away from the second cooling chamber is used to connect to an external cooling source.

[0014] Furthermore, the hole-sweeping scraper includes a cantilever bracket, a spring telescopic rod, and a scraping blade; The cantilever bracket is fixedly mounted on the side wall of the rotating rod; The bottom end of the spring telescopic rod is mounted on the cantilever bracket, and its output end is connected to the scraper plate; the spring telescopic rod is used to provide the scraper plate with an elastic lifting force toward the partition.

[0015] Furthermore, the outer cover of the spring telescopic rod is equipped with a corrugated tube made of polytetrafluoroethylene. The upper and lower ends of the corrugated tube are respectively sealed and connected to the bottom of the scraper plate and the cantilever bracket, forming a sealed and corrosion-resistant cavity that isolates the spring telescopic rod from the reaction liquid.

[0016] Furthermore, a rotating grid cylinder is coaxially rotatably sleeved on the outside of the light-transmitting sleeve; A radially extending elastic lever is fixed on the side wall of the rotating rod, and the free end of the elastic lever is intermittently driven to the side wall of the rotating grid cylinder. The side wall of the rotating grid cylinder is alternately provided with light-transmitting slits and light-shielding baffles along the circumference, and the multiple light-transmitting slits and light-shielding baffles are evenly distributed at intervals. The outer wall of the rotating grid cylinder is provided with a force-bearing protrusion that cooperates with the elastic lever.

[0017] The present invention also provides a method for using the above-mentioned continuous photochlorination reactor for toluene side chains, comprising the following steps: S1. First, turn on the ultraviolet light source and external cooling source, inject toluene raw material into the liquid phase space of the reactor, and at the same time, the external gas source will sequentially input chlorine gas through the gas inlet pipe and the inner cavity of the sleeve into the inner cavity of the hollow rotating rod. S2. The rotating rod drives the stirring rod to rotate at high speed. A local negative pressure zone and a wake vortex are formed on the back surface of the stirring rod, which draws out the chlorine gas in the inner cavity of the stirring rod through the gas distribution hole and performs primary bubble refinement under the tearing force of the vortex. S3. After primary refinement, the bubbles float upwards. The dynamic and static shearing forces formed between the high-speed rotating sweeping scraper and the fixed partition force the bubbles passing through the bubble-breaking holes to be forcibly cut off and crushed, thus achieving secondary refinement. S4. The microbubbles passing through the bubble-breaking holes converge in the gas storage arc surface at the bottom of the baffle plate and slide slowly along the arc surface, where they are punctured by the bubble-breaking burrs. At the same time, the ultraviolet light reflector focuses ultraviolet light on this area to trigger a photochlorination reaction. The heat released by the reaction is carried away in real time by the cooling medium in the first and second cooling chambers.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This scheme drives the stirring rod to rotate at high speed. During the rotation of the stirring rod, a water vortex with suction force is generated on the back water surface of the stirring rod. The bubbles will be sucked into the vortex, and the large bubbles in the vortex will be torn and broken. The high-speed rotating sweeping scraper and the stationary baffle cooperate to cut the bubbles that are passing through the bubble breaking hole. When the bubbles passing through the bubble breaking hole move along the lower surface of the baffle and pass through the gap between the burrs, the bubbles with a volume larger than the gap between the burrs will be blocked by the side wall of the burrs and broken again. This can prolong the time when the bubbles in the reaction liquid are in a small volume state, increase the contact probability between the reactants in the bubbles and the reaction liquid, and improve the reaction efficiency.

[0019] (2) This scheme creates a concave gas storage arc surface at the bottom of the baffle plate, allowing the floating bubbles to move along the arc surface. During this process, the bubbles gather on the surface of the arc surface. At this time, under the action of the ultraviolet light reflection layer coated on the surface of the baffle plate, the transmitted ultraviolet light can be reflected upward and focused into the gas storage arc surface, forming high-intensity ultraviolet quantum radiation locally, which improves the photochemical initiation rate of chlorine molecules and the overall reaction conversion rate.

[0020] (3) By setting up a first cooling chamber and a second cooling chamber, this scheme can absorb the heat released by the photochlorination reaction under the action of heat exchange; prevent the small bubbles from expanding due to local high temperature, further increase the contact probability between the reactants in the bubbles and the reaction liquid, and improve the reaction efficiency. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a front cross-sectional view of the present invention; Figure 3 This is a schematic diagram of the combined structure of the cleaning scraper and the rotating rod of the present invention; Figure 4 This is a schematic diagram of the structure of the cleaning scraper of the present invention; Figure 5 This is a schematic diagram of the combined structure of the baffle and the bubble-breaking burr of the present invention; Figure 6 This is a schematic cross-sectional view of the combined structure of the rotating rod, baffle plate, and partition plate of the present invention; Figure 7 This is a schematic diagram of the combined structure of the rotating grid cylinder, the light-transmitting slit, and the light-shielding baffle of the present invention. Figure 8 This is a cross-sectional view of the rotating grid cylinder of the present invention.

[0022] Explanation of the labels in the diagram: 1. Reactor; 101. Continuous feed inlet; 102. Continuous discharge outlet; 103. Tail gas outlet; 2. Transparent sleeve; 3. Ultraviolet light source; 4. Rotating rod; 5. Drive motor; 6. Stirring rod; 7. Baffle; 8. Gas distribution hole; 9. Bubble breaking hole; 10. Scraper; 1001. Cantilever support; 1002. Spring telescopic rod; 1003. Scraper; 11. Baffle plate; 12. Bubble breaking burr; 13. Sleeve; 14. Air inlet; 15. Air inlet pipe; 16. First cooling chamber; 17. Second cooling chamber; 18. Cooling medium output pipe; 19. Cooling medium input pipe; 20. Corrugated pipe; 21. Rotating grid cylinder; 22. Transparent slit; 23. Light-shielding baffle; 24. Force-bearing protrusion; 25. Elastic lever; 26. Guide pipe. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] Example 1:

[0025] Please see Figures 1 to 8 A continuous photochlorination reaction apparatus for toluene side chains and its method of use, comprising a reaction vessel 1, a light-transmitting sleeve 2, and an ultraviolet light source 3; The reactor 1 is provided with a continuous feed inlet 101, a continuous discharge outlet 102 and a tail gas outlet 103; the ultraviolet light source 3 is sealed and built into the light-transmitting sleeve 2, which is vertically fixed and inserted into the inner top wall of the reactor 1, and extends downward and is immersed in the liquid phase space inside the reactor 1. A hollow rotating rod 4 is rotatably installed in the inner cavity of the reactor 1. A drive motor 5 is fixedly installed on the top of the reactor 1. The output end of the drive motor 5 extends into the inner cavity of the reactor 1 and is fixedly connected to the top of the rotating rod 4, so that the rotating rod 4 can be rotated by the drive motor 5. Hollow stirring rods 6 are evenly inserted on the side wall of the rotating rod 4, and the inner cavity of the stirring rod 6 is connected to the inner cavity of the rotating rod 4. The reactor 1 is equipped with a gas supply mechanism for supplying gas to the inner cavity of the rotating rod 4; A partition 7 is horizontally fixed in the liquid phase space inside the reactor 1. A rotating rod 4 passes through the partition 7 and rotates with it. A stirring rod 6 is distributed below the partition 7. The side wall of the stirring rod 6 is provided with several air distribution holes 8 that connect its inner cavity with the inner cavity of the reactor 1. The air distribution holes 8 are located on the back water surface in the direction of rotation of the stirring rod 6, and the channels of the air distribution holes 8 are in the shape of a funnel mouth that gradually expands from the inside to the outside. When the drive motor 5 drives the rotating rod 4 and the stirring rod 6 to rotate at high speed in the reaction liquid, a negative pressure zone and a wake vortex will be formed on the back water surface of the stirring rod 6.

[0026] At this moment, the chlorine gas in the inner cavity of the stirring rod 6 is drawn into the high-speed vortex of the wake.

[0027] Under the tearing force of the vortex, the gas flowing out of the air distribution hole 8 is torn into small bubbles, reducing the probability of large bubbles appearing. The baffle 7 has uniformly distributed bubble-breaking holes 9 on its surface; when the floating chlorine bubbles pass through the bubble-breaking holes 9, they are broken by the physical shear of the bottom wall of the bubble-breaking holes 9, thereby breaking up the large bubbles that have coalesced; a radially extending sweeping scraper 10 is fixed on the side wall of the rotating rod 4, and the upper edge of the sweeping scraper 10 is in sliding contact with the lower surface of the baffle 7, or maintains a gap of 0.5mm to 2mm; and the sweeping scraper 10 rotates with the drive motor 5 at a set speed of 200-500r / min and sweeps across the area below the bubble-breaking holes 9; under the drive of the drive motor 5, the sweeping scraper 10 rotates synchronously with the rotating rod 4 and sweeps across the area below the bubble-breaking holes 9, and the sweeping scraper 10, which rotates at high speed with the rotating rod 4, forms a dynamic fluid shear surface; When bubbles gather below the bubble-breaking hole 9 and pass through it, a shearing action is created between the high-speed sweeping scraper 10 and the stationary partition 7, forcibly cutting and crushing the large bubbles. At the same time, the rotation of the sweeping scraper 10 generates a local forced flow guiding effect, forcibly pushing the crushed small bubbles into the bubble-breaking hole 9.

[0028] This allows for control of bubble size, preventing bubbles from coalescing and forcibly punching holes when gas volume surges.

[0029] like Figure 2 As shown, several inclined baffles 11 are fixedly provided on the upper surface of the baffle 7, and each baffle 11 is arranged in a circular array with the rotating rod 4 as the center; the lower surface of the baffle 11 is provided with bubble-breaking burrs 12; the refined bubbles passing through the bubble-breaking holes 9 are blocked by the baffles 11 during the upward floating process, changing their movement trajectory, and are punctured and sheared by the bubble-breaking burrs 12 when sliding along the lower surface of the baffle 11, which not only further reduces the bubble particle size, but also prolongs the residence time of the bubbles in the liquid phase, thereby improving the gas-liquid contact area and mass transfer efficiency.

[0030] like Figure 5 As shown, the lower surface of the baffle 11 is a concave gas storage arc surface. Preferably, the gas storage arc surface has a parabolic cylindrical or semi-elliptical cylindrical cross-sectional profile along its extension direction.

[0031] As the bubbles pass through the bubble-breaking hole 9 rise, they are forced to change their original vertical upward trajectory due to the obstruction of the lower surface of the baffle plate 11. Because the lower surface of the baffle plate 11 is designed as a concave gas storage arc surface, the bubbles will converge towards the high point of the arc surface under the action of buoyancy and slowly slide along the surface, which prolongs the residence time of the bubbles in the liquid phase and increases the local gas volume. Furthermore, the bubble-breaking burr array 12 is distributed within the gas storage arc surface; during the sliding process, the bubbles are subjected to secondary forced puncture and shearing by the bubble-breaking burrs 12 distributed within the arc surface.

[0032] like Figure 2 , Figure 5 As shown, the upper surface of the partition 7 is coated with an ultraviolet light reflecting layer made of silicon dioxide interference film, and the ultraviolet light reflecting layer faces upward directly towards the gas storage arc surface of the baffle 11. Due to the concave structure of the gas storage arc surface, bubbles converge on the surface of the arc surface. In conjunction with the ultraviolet light reflecting layer coated on the upper surface of the partition 7, the attenuated ultraviolet light can be reflected upward again and focused into the gas storage arc surface along the optical focal point of the parabolic or elliptical surface, providing ultraviolet quantum radiation, thereby improving the photochemical initiation rate and reaction conversion rate of chlorine molecules.

[0033] like Figure 6 As shown, the gas supply mechanism includes a sleeve 13 fixedly installed inside the reactor 1; The hollow rotating rod 4 is rotatably inserted through the sleeve 13, and the two ends of the sleeve 13 are slidably sealed with the outer wall of the rotating rod 4; An air inlet 14 communicating with the inner cavity of the sleeve 13 is provided on the side wall of the section of the rotating rod 4 covered by the sleeve 13. An air inlet pipe 15 is installed on the side wall of the reactor 1, one end of which is connected to the inner cavity of the sleeve 13. The end of the air inlet pipe 15 away from the sleeve 13 is connected to an external air source. In summary, the gas output from the external gas source can be stably delivered to the inner cavity of the rotating rod 4 through the air inlet pipe 15, the inner cavity of the sleeve 13 and the air inlet hole 14 in sequence.

[0034] like Figure 6 As shown, the baffle 11 has a first cooling chamber 16 inside, and the partition 7 has a second cooling chamber 17 inside. The first cooling chamber 16 and the second cooling chamber 17 are connected by a guide pipe 26; wherein, the guide pipe 26 is fixedly inserted into the bottom wall of the first cooling chamber 16, and the bottom end of the guide pipe 26 extends to the top wall surface of the second cooling chamber 17. A cooling medium output pipe 18 and a cooling medium input pipe 19 are respectively inserted into the first cooling chamber 16 and the second cooling chamber 17. The end of the cooling medium input pipe 19 away from the second cooling chamber 17 is used to connect to an external cooling source. During operation, the cooling medium output from the external cooling source is injected into the second cooling chamber 17 through the cooling medium inlet pipe 19 under the pressure of the circulating pump. It then flows into the first cooling chamber 16 through the guide pipe 26 and is finally discharged through the cooling medium outlet pipe 18. The pressure-driven flow rate is sufficient to overcome the high-temperature thermal resistance of the gas accumulation zone, preventing vaporization resistance from forming at the narrow end of the first cooling chamber 16, thus forming a complete cooling cycle. The external cooling source can be a low-temperature chiller unit.

[0035] By injecting a cooling medium into the first cooling chamber 16 and the second cooling chamber 17 provided on the baffle 11 and the partition 7, the cooling medium can absorb the heat released by the photochlorination reaction under the action of heat exchange. This prevents the microbubbles from expanding due to local high temperature, ensuring the contact probability between the reactants in the bubbles and the reaction liquid, thereby improving the selectivity of the target product and the utilization rate of chlorine gas.

[0036] like Figure 4 As shown, the hole-sweeping scraper 10 includes a cantilever bracket 1001, a spring telescopic rod 1002, and a scraper 1003; The cantilever bracket 1001 is fixedly mounted on the side wall of the rotating rod 4; The bottom end of the spring telescopic rod 1002 is mounted on the cantilever bracket 1001, and its output end is connected to the scraper plate 1003. The spring telescopic rod 1002 is used to provide the scraper plate 1003 with an elastic lifting force toward the partition plate 7 so that the upper edge of the scraper plate 1003 always remains in sliding contact with the lower surface of the partition plate 7.

[0037] like Figure 4 As shown, the outer cover of the spring telescopic rod 1002 is provided with a corrugated tube 20 made of polytetrafluoroethylene. The upper and lower ends of the corrugated tube 20 are respectively sealed and connected to the bottom of the scraper plate 1003 and the cantilever bracket 1001, forming a sealed and corrosion-resistant cavity that isolates the spring telescopic rod 1002 from the reaction liquid.

[0038] A corrugated tube 20 made of corrosion-resistant material completely encloses the metal spring telescopic rod 1002. The flexibility of the corrugated tube 20 not only does not affect the vertical adaptive displacement of the scraper 1003, but also isolates the spring from corrosion by chlorine and hydrochloric acid, as well as from jamming caused by crystallization.

[0039] like Figure 8 As shown, a rotating grid cylinder 21 is coaxially rotatably sleeved on the outside of the light-transmitting sleeve 2; A radially extending elastic lever 25 is fixed on the side wall of the rotating rod 4. The elastic lever 25 is made of titanium alloy or spring steel with an outer polytetrafluoroethylene anti-corrosion layer. The free end of the elastic lever 25 is intermittently driven to the side wall of the rotating grid cylinder 21. The side wall of the rotating grid cylinder 21 is alternately provided with light-transmitting slits 22 and light-shielding baffles 23 along the circumferential direction, and the multiple light-transmitting slits 22 and light-shielding baffles 23 are evenly spaced; in addition, a damping bearing is provided at the connection between the light-transmitting sleeve 2 and the rotating grid cylinder 21 to absorb the impact force generated by the rotating grid cylinder 21 during step rotation.

[0040] The outer wall of the rotating grid cylinder 21 is provided with a force-receiving protrusion 24 that cooperates with the elastic lever 25.

[0041] During operation, as the rotating rod 4 rotates at high speed, the elastic lever 25 moves in a circular motion. When the free end of the elastic lever 25 contacts the force-bearing protrusion 24 of the rotating grid cylinder 21, the elastic lever 25 is first resisted and undergoes elastic deformation, converting mechanical energy into elastic potential energy. As the rotating rod 4 continues to pass the critical point, the lever instantly rebounds and releases energy. Through the combined action of friction and elasticity, it drives the rotating grid cylinder 21 to rotate. At this time, the light-blocking baffle 23 and the light-transmitting slit 22 alternate.

[0042] This allows the continuous ultraviolet light to be transformed into a pulsed light-like pattern, which alternating between bright and dark, preventing localized overheating caused by continuous illumination.

[0043] The present invention also provides a method for using the above-mentioned continuous photochlorination reactor for toluene side chains, comprising the following steps: S1. First, turn on the ultraviolet light source 3 and the external cooling source, and pump the toluene raw material into the liquid phase space of the reactor 1 through the continuous feed port 101. At the same time, the external gas source feeds chlorine gas into the hollow rotating rod 4 through the gas inlet pipe 15 and the inner cavity of the sleeve 13. S2. Start the drive motor 5 to drive the rotating rod 4 and the stirring rod 6 to rotate at high speed. The back surface of the stirring rod 6 forms a local negative pressure zone and a wake vortex, which draws out the chlorine gas in the inner cavity of the stirring rod 6 through the air distribution hole 8 and performs primary bubble refinement under the tearing force of the vortex. S3. After primary refinement, the bubbles float upwards. The dynamic and static shearing forces formed between the high-speed rotating sweeping scraper 10 and the fixed partition 7 forcefully cut and crush the bubbles passing through the bubble-breaking holes 9, thus achieving secondary refinement. S4. The microbubbles passing through the bubble-breaking holes 9 converge in the gas storage arc surface at the bottom of the baffle plate 11 and slowly slide along the arc surface, and are punctured by the bubble-breaking burrs 12. At the same time, the ultraviolet light reflector focuses the ultraviolet light on the area to trigger a highly efficient photochlorination reaction. The heat released by the reaction is carried away in real time by the cooling medium in the first cooling chamber 16 and the second cooling chamber 17.

[0044] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concepts, should be covered within the scope of protection of the present invention.

Claims

1. A continuous photochlorination reaction apparatus for toluene side chains, comprising a reaction vessel (1), a light-transmitting sleeve (2), and an ultraviolet light source (3). Its features are: The reactor (1) has a hollow rotating rod (4) rotating inside. Hollow stirring rods (6) are evenly inserted on the side wall of the rotating rod (4), and the inner cavity of the stirring rod (6) is connected to the inner cavity of the rotating rod (4). The reactor (1) is equipped with a gas supply mechanism for supplying gas to the inner cavity of the rotating rod (4); A partition (7) is horizontally fixed in the inner cavity of the reactor (1). The rotating rod (4) passes through the partition (7) and rotates in coordination with it. The stirring rod (6) is distributed below the partition (7). The stirring rod (6) has several air holes (8) on its side wall. The air holes (8) are located on the back side of the stirring rod (6) in the direction of rotation, and the channels of the air holes (8) are funnel-shaped with the diameter gradually expanding from the inside to the outside. The partition (7) has bubble-breaking holes (9) evenly distributed on its surface; a radially extending sweeping scraper (10) is fixed on the side wall of the rotating rod (4), the upper edge of the sweeping scraper (10) is slidably fitted with the lower surface of the partition (7), and the sweeping scraper (10) rotates with the rotating rod (4) and sweeps across the area below the bubble-breaking holes (9); The upper surface of the partition (7) is fixedly provided with a plurality of inclined baffles (11), and the lower surface of the baffles (11) is provided with bubble-breaking burrs (12).

2. The continuous photochlorination reactor for toluene side chains according to claim 1, characterized in that: Each of the baffles (11) is arranged in a circular array with the rotating rod (4) as the center.

3. The continuous photochlorination reactor for toluene side chains according to claim 2, characterized in that: The lower surface of the baffle (11) is a concave gas storage arc surface; Furthermore, the bubble-breaking burr (12) array is distributed within the gas storage arc surface.

4. The continuous photochlorination reactor for toluene side chains according to claim 3, characterized in that: The upper surface of the partition (7) is coated with an ultraviolet light reflective layer, and the ultraviolet light reflective layer faces upward directly onto the gas storage arc surface of the baffle (11).

5. The continuous photochlorination reactor for toluene side chains according to claim 4, characterized in that: The gas supply mechanism includes a sleeve (13) fixedly installed inside the reactor (1); The hollow rotating rod (4) is rotatably inserted through the sleeve (13), and the two ends of the sleeve (13) are slidably sealed with the outer wall of the rotating rod (4); The rotating rod (4) has an air inlet (14) on the side wall of the section covered by the sleeve (13) that communicates with the inner cavity of the sleeve (13). An air inlet pipe (15) with one end connected to the inner cavity of the sleeve (13) is provided on the side wall of the reactor (1). The end of the air inlet pipe (15) away from the sleeve (13) is connected to an external air source.

6. The continuous photochlorination reactor for toluene side chains according to claim 5, characterized in that: The baffle (11) has a first cooling chamber (16) inside, and the partition (7) has a second cooling chamber (17) inside. The first cooling chamber (16) and the second cooling chamber (17) are connected by a guide pipe (26); Cooling medium output pipe (18) and cooling medium input pipe (19) are respectively inserted into the first cooling chamber (16) and the second cooling chamber (17). The end of the cooling medium input pipe (19) away from the second cooling chamber (17) is used to communicate with an external cooling source.

7. The continuous photochlorination reactor for toluene side chains according to claim 6, characterized in that: The hole-sweeping scraper (10) includes a cantilever bracket (1001), a spring telescopic rod (1002), and a scraper (1003). The cantilever bracket (1001) is fixedly mounted on the side wall of the rotating rod (4); The bottom end of the spring telescopic rod (1002) is mounted on the cantilever bracket (1001), and its output end is connected to the scraper plate (1003); the spring telescopic rod (1002) is used to provide the scraper plate (1003) with an elastic lifting force toward the partition plate (7).

8. The continuous photochlorination reactor for toluene side chains according to claim 7, characterized in that: The outer cover of the spring telescopic rod (1002) is provided with a corrugated tube (20) made of polytetrafluoroethylene. The upper and lower ends of the corrugated tube (20) are respectively sealed and connected to the bottom of the scraper plate (1003) and the cantilever bracket (1001) to form a sealed and corrosion-resistant cavity that isolates the spring telescopic rod (1002) from the reaction liquid.

9. The continuous photochlorination reactor for toluene side chains according to claim 8, characterized in that: The light-transmitting sleeve (2) is coaxially rotatably fitted with a rotating grid cylinder (21) on its outside. A radially extending elastic lever (25) is fixed on the side wall of the rotating rod (4), and the free end of the elastic lever (25) is intermittently driven to the side wall of the rotating grid cylinder (21). The rotating grid cylinder (21) has light-transmitting slits (22) and light-shielding baffles (23) alternately arranged along the circumferential direction on its side wall, and the multiple light-transmitting slits (22) and light-shielding baffles (23) are evenly spaced. The outer wall of the rotating grid cylinder (21) is provided with a force-bearing protrusion (24) that cooperates with the elastic lever (25).

10. A method of using the continuous photochlorination reactor for toluene side chains as described in claim 9, characterized in that: Includes the following steps: S1. First, turn on the ultraviolet light source (3) and the external cooling source, inject the toluene raw material into the liquid phase space of the reactor (1), and at the same time, the external gas source will input chlorine gas into the hollow rotating rod (4) through the gas inlet pipe (15) and the inner cavity of the sleeve (13). S2. The rotating rod (4) in the rotating state drives the stirring rod (6) to rotate at high speed. The back surface of the stirring rod (6) forms a local negative pressure zone and a tail vortex, which draws out the chlorine gas in the inner cavity of the stirring rod (6) through the air distribution hole (8) and performs primary bubble refinement under the tearing force of the vortex. S3. After primary refinement, the bubbles float upwards. The dynamic and static shearing forces formed between the high-speed rotating sweeping scraper (10) and the fixed partition (7) force the bubbles passing through the bubble breaking hole (9) to be cut off and crushed, thus achieving secondary refinement. S4. The microbubbles passing through the bubble-breaking hole (9) converge in the gas storage arc surface at the bottom of the baffle plate (11) and slide slowly along the arc surface, and are punctured by the bubble-breaking burr (12); at the same time, the ultraviolet light reflection layer focuses the ultraviolet light on the area to trigger the photochlorination reaction, and the heat released by the reaction is carried away in real time by the cooling medium in the first cooling chamber (16) and the second cooling chamber (17).

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