Continuous reaction device and method for producing 2-amino-4-methylbenzothiazole

Abstract

The invention discloses a continuous reaction device and method for producing 2-amino-4-methylbenzothiazole, and belongs to the technical field of compound production. The invention relates to a continuous reaction device for producing 2-amino-4-methylbenzothiazole, which comprises a first-stage reaction kettle and further comprises a stirring mechanism arranged in the first-stage reaction kettle and used for stirring chlorine and a mixed solution in the first-stage reaction kettle; the driving mechanism is arranged at the top of the first-stage reaction kettle and is used for driving the stirring mechanism to perform stirring action in the first-stage reaction kettle; the chlorine injection mechanism is connected with the stirring mechanism; the air exhaust mechanism is arranged at the top of the first-stage reaction kettle and is connected with the driving mechanism; the multistage reaction kettles are adopted for continuous operation to eliminate downtime, so that the problem of low production efficiency caused by repeated heating and cooling due to the use of intermittent reaction kettles in the traditional process is solved, the chlorine utilization rate is improved, and the production and processing cost is effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of compound production, and in particular to a continuous reaction device and method for 2-amino-4-methylbenzothiazole production. BACKGROUND

[0002] 5-methyl-1,2,4-triazolo[3,4-b]-benzothiazole (tricyclazole) is a highly effective, systemic azole fungicide, which is particularly effective against rice blast and is also effective against rice blast fungi that have developed resistance to other fungicides. Among them, 2-amino-4-methylbenzothiazole is one of the important intermediates for the synthesis of the pesticide tricyclazole, which is obtained by cyclization of N-o-tolylthiourea. At present, the main synthesis method is to use chlorine cyclization.

[0003] However, the conventional technology for preparing 2-amino-4-methylbenzothiazole is to pass chlorine into N-o-tolylthiourea and add dichloroethane. Since the reaction material is relatively viscous, only a batch reaction kettle can be used for reaction production. The reaction pressure in the kettle is self-adaptively adjusted by the system, and the product is obtained after 2-4 hours. Finally, the reaction product is discharged after cooling. The device needs to be repeatedly filled with materials and heated and cooled during use, and the reaction time is greatly prolonged due to slow heating and cooling, resulting in low production efficiency and high energy consumption. Moreover, since the contact area between chlorine and the mixed solution is small after the chlorine is passed into the reaction kettle, the chlorine and the mixed solution cannot fully react, and the unreacted chlorine is directly discharged, resulting in low utilization rate of chlorine and a large amount of waste in production cost. SUMMARY

[0004] The present application aims to solve the problems in the prior art and provides a continuous reaction device and method for 2-amino-4-methylbenzothiazole production.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions: A continuous reaction device for 2-amino-4-methylbenzothiazole production includes a primary reaction kettle and further includes: A stirring mechanism is arranged in the primary reaction kettle and is used to stir chlorine and a mixed solution in the primary reaction kettle; A driving mechanism is arranged at the top of the primary reaction kettle and is used to drive the stirring mechanism to perform stirring action in the primary reaction kettle; A chlorine injection mechanism is connected with the stirring mechanism and is used to uniformly distribute chlorine in the primary reaction kettle; and an air extraction mechanism is arranged at the top of the primary reaction kettle and is connected with the driving mechanism, and is used to recycle and reuse the unreacted chlorine in the primary reaction kettle; The first reaction kettle is provided with a plurality of sieve plate assemblies connected with the stirring mechanism from top to bottom, which is used to slow down the rising speed of chlorine in the mixed solution.

[0006] Preferably, the stirring mechanism comprises a stirring pipe rotatably connected in the first reaction kettle and a stirring component arranged outside the stirring pipe, and the driving mechanism comprises a mounting seat fixed on the top of the first reaction kettle, a driving motor fixed on the mounting seat, a driving gear connected with the output shaft of the driving motor, and a driven gear arranged on the stirring pipe and engaged with the driving gear.

[0007] Preferably, the air extraction mechanism comprises an air extraction pipe fixedly connected with the mounting seat, a one-way air inlet pipe arranged between the air extraction pipe and the inner cavity of the first reaction kettle, and an air extraction component arranged in the air extraction pipe and connected with the driving mechanism.

[0008] Preferably, the air extraction component comprises a first connecting plate connected with the output shaft of the driving motor, a second connecting plate movably connected with the first connecting plate, a sliding rod movably connected with the second connecting plate, an elastic telescopic rod fixedly connected with the sliding rod, and a piston connected with the end of the elastic telescopic rod away from the sliding rod, the piston being slidably connected in the air extraction pipe, and a one-way air outlet pipe being further connected to the air extraction pipe, the end of the one-way air outlet pipe away from the air extraction pipe being connected with the chlorine injection mechanism.

[0009] Preferably, the chlorine injection mechanism comprises a gas guide pipe arranged in the stirring pipe, a valve body rotatably connected with the top of the gas guide pipe, a spiral hose connected with the end of the gas guide pipe away from the valve body, and an aeration plate connected with the spiral hose, the aeration plate being provided with a plurality of aeration heads.

[0010] Preferably, the valve body is a three-way valve, two interfaces of the three-way valve being connected with the one-way air outlet pipe and the gas guide pipe respectively, and the remaining one interface being connected with a gas conveying pipe, the end of the gas conveying pipe away from the three-way valve being connected with a chlorine supply device.

[0011] Preferably, the chlorine injection mechanism further comprises a protective shell fixedly connected with the bottom of the stirring pipe, a reciprocating screw rod rotatably connected in the protective shell, a sleeve threadedly connected with the aeration plate on the reciprocating screw rod, an opening formed in the top of the protective shell, a fixed plate rotatably connected with the top opening of the protective shell, the fixed plate being fixedly connected with the inner wall of the first reaction kettle through a connecting plate, a fixed bevel gear fixedly arranged on the lower side of the fixed plate, and a movable bevel gear arranged on the reciprocating screw rod and engaged with the fixed bevel gear.

[0012] Preferably, the sieve plate assembly comprises a spherical shell and a sieve plate body arranged outside the spherical shell, a movable block is slidably connected to the bottom of the sieve plate body, the movable block is movably connected with a movable rod through a pin shaft, a sliding block is movably connected to the end of the movable rod away from the sieve plate body, a wave track groove matched with the sliding block is formed in the inner wall of the primary reactor, a sliding groove for the sliding of the movable block is formed in the bottom of the sieve plate body, a spherical joint slidably connected with the spherical shell is fixed to the outer side of the stirring pipe, a limiting block is fixed to the outer side of the spherical joint, and a limiting groove for the sliding of the limiting block is formed in the inner wall of the spherical shell.

[0013] Preferably, the device further comprises a micro-mixer, a gas-liquid separation tank, a secondary reactor with the same structure as the primary reactor, and an ice acetic acid cooler for cooling the material, the primary reactor and the secondary reactor are both provided with a feeding pipe and a discharging pipe, N-o-tolylthiourea and pre-cooled ice acetic acid are preliminarily mixed in the micro-mixer, the mixed solution is continuously reacted with chlorine in the primary reactor and the secondary reactor, and then the 2-amino-4-methylbenzothiazole solution is prepared in the gas-liquid separation tank, and an S-shaped pipe is arranged between the feeding end of the feeding pipe of the primary reactor and the discharging end of the micro-mixer.

[0014] The application also discloses a continuous reaction method for the production of 2-amino-4-methylbenzothiazole. S1: preliminary mixing of raw materials: pre-cooled ice acetic acid and N-o-tolylthiourea are sent into the micro-mixer for preliminary homogenization to form a mixed solution; S2: primary continuous chlorination reaction: the mixed solution enters the bottom of the primary reactor through the feeding pipe; dynamic injection of chlorine: the driving motor drives the stirring pipe to rotate, the movable bevel gear is engaged with the fixed bevel gear to drive the reciprocating lead screw, the sleeve drives the aeration plate to move along the reciprocating lead screw, the aeration plate expands or shrinks in a circular spiral track, and the chlorine is dispersed in the bottom of the reactor, thereby increasing the aeration range of the aeration head of the aeration plate; S3: cooperative movement of the sieve plate: the stirring pipe drives the sieve plate body to rotate through the spherical joint, the wave track groove cooperates with the sliding block, the sieve plate body reciprocatingly tilts and swings up and down, the chlorine bubble path is forced to be tortuous during the upward movement, and a dynamic flow resistance process is formed, thereby prolonging the residence time of the bubbles in the mixed solution; S4: synchronous pumping and regeneration: the driving motor drives the piston to reciprocate in the pumping pipe through the first connecting plate and the second connecting plate; When the piston moves to the right, the unreacted chlorine gas at the top of the reactor is sucked through the one-way air inlet pipe; When the piston moves left, the chlorine gas is extruded and returned to the valve body of the three-way valve through the one-way exhaust pipe, mixed with the newly supplemented chlorine gas, and then re-injected into the reaction zone inside the kettle body; S5: Secondary continuous reaction and product separation: the primary reaction liquid enters the secondary reaction kettle through the discharge pipe for deep chlorination; The final reaction liquid enters the gas-liquid separation tank to obtain a high-purity 2-amino-4-methylbenzothiazole solution.

[0015] Compared with the prior art, the present application provides a continuous reaction device and method for the production of 2-amino-4-methylbenzothiazole, which has the following beneficial effects: 1. The continuous reaction device and method for the production of 2-amino-4-methylbenzothiazole, by replacing dichloroethane with glacial acetic acid and mixing it with N-o-tolylthiourea, avoids the problem that the traditional process of mixing dichloroethane with chlorine gas and N-o-tolylthiourea after reaction is relatively viscous, and can only use a batch reaction kettle for reaction production. The use of multi-stage reaction kettles for continuous operation eliminates downtime, thereby solving the problem of low production efficiency caused by repeated heating and cooling in the traditional process using a batch reaction kettle, and effectively improving the production and processing efficiency of the product.

[0016] 2. The continuous reaction device and method for the production of 2-amino-4-methylbenzothiazole, by engaging the movable bevel gear with the fixed bevel gear to drive the reciprocating lead screw, the sleeve drives the aeration plate to move along the reciprocating lead screw, the aeration plate expands or shrinks in a circular spiral track, and the chlorine gas is dispersed in the kettle bottom, thereby increasing the aeration range of the aeration head of the aeration plate, improving the utilization rate of chlorine gas, and effectively reducing the production and processing cost.

[0017] 3. The continuous reaction device and method for the production of 2-amino-4-methylbenzothiazole, by reciprocating movement of the piston in the exhaust pipe, when the piston moves left, the unreacted chlorine gas at the top of the kettle is sucked through the one-way air inlet pipe, when the piston moves right, the chlorine gas is extruded and returned to the valve body of the three-way valve through the one-way exhaust pipe, mixed with the newly supplemented chlorine gas, and then re-injected into the reaction zone inside the kettle body, the chlorine gas that has not reacted with the mixed solution is recovered and reused, further improving the utilization rate of chlorine gas, and effectively reducing the production and processing cost.

[0018] 4. The continuous reaction device and method for the production of 2-amino-4-methylbenzothiazole, by using the spherical joint to drive the screen body to rotate through the stirring pipe, and by cooperating the wave track groove with the sliding block, the screen body tilts and swings up and down, the chlorine gas bubble path is forced to zigzag during the upward process, and a dynamic flow resistance process is formed, thereby prolonging the residence time of the gas bubble in the mixed solution, so that the chlorine gas fully reacts with the mixed solution; the reciprocating aeration plate and the swinging screen form a shear turbulent flow, which can handle solutions with excessively high viscosity, avoid the problem of uneven mixing caused by viscous material, and improve the product processing quality.

[0019] 5. The continuous reaction device and method for producing 2-amino-4-methylbenzothiazole solves the problem of low gas-liquid reaction efficiency of high viscosity system by optimizing mechanical linkage and fluid dynamics, and provides an innovative engineering example for continuous production of pesticide intermediates. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The structure schematic diagram of the present application is shown in the figure; Figure 2 The structure schematic diagram of the present application is shown in the figure; Figure 3 The structure schematic diagram of the present application is shown in the figure; Figure 4 The structure schematic diagram of the present application is shown in the figure; Figure 5 The structure schematic diagram of the present application is shown in the figure; Figure 6 The structure schematic diagram of the present application is shown in the figure; Figure 5 The structure schematic diagram of the present application is shown in the figure; Figure 7 The structure schematic diagram of the present application is shown in the figure; Figure 8 The structure schematic diagram of the present application is shown in the figure; Figure 9 The structure schematic diagram of the present application is shown in the figure; Figure 8 The structure schematic diagram of the present application is shown in the figure; Figure 10 The structure schematic diagram of the present application is shown in the figure; Figure 11 The structure schematic diagram of the present application is shown in the figure;

[0021] In the figure: 1, primary reaction kettle; 2, stirring mechanism; 201, stirring pipe; 202, stirring part; 3, driving mechanism; 301, mounting seat; 302, driving motor; 3021, first connecting plate; 3022, second connecting plate; 3023, slide rod; 3024, elastic telescopic rod; 3025, piston; 303, driving gear; 304, driven gear; 4, chlorine gas injection mechanism; 401, gas guide pipe; 402, valve body; 4021, gas conveying pipe; 403, spiral hose; 404, aeration plate; 5, air extraction mechanism; 501, air extraction pipe; 502, one-way air inlet pipe; 503, one-way air outlet pipe; 6, protective shell; 601, reciprocating screw rod; 6011, movable bevel gear; 602, sleeve; 7, fixed plate; 701, fixed bevel gear; 8, spherical shell; 801, sieve plate body; 8011, chute; 802, movable rod; 803, slide block; 804, limiting groove; 805, movable block; 9, wave track groove; 10, spherical joint; 1001, limiting block; 11, S-shaped pipe; 12, glacial acetic acid cooler; 13, micro-mixer; 14, gas-liquid separation tank; 15, secondary reaction kettle; 151, feeding pipe; 152, discharging pipe. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments of the present application.

[0023] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0024] As Figure 1 , Figure 2 , Figure 3 and Figure 11As shown, the present embodiment proposes a continuous reaction device for 2-amino-4-methylbenzothiazole production, which comprises a primary reaction kettle 1, and further comprises: a stirring mechanism 2 for stirring chlorine gas and the mixed solution in the primary reaction kettle 1, a driving mechanism 3 for driving the stirring mechanism 2 to make stirring action in the primary reaction kettle 1, a chlorine gas injection mechanism 4 for uniformly distributing chlorine gas in the primary reaction kettle 1, and an air extraction mechanism 5 for recycling unreacted chlorine gas in the primary reaction kettle 1, the stirring mechanism 2 is arranged in the primary reaction kettle 1, the driving mechanism 3 is arranged at the top of the primary reaction kettle 1, the chlorine gas injection mechanism 4 is connected with the stirring mechanism 2, and the air extraction mechanism 5 is arranged at the top of the primary reaction kettle 1 and connected with the driving mechanism 3, wherein a plurality of sieve plate assemblies connected with the stirring mechanism 2 are arranged in the primary reaction kettle 1 from top to bottom, for slowing down the rising speed of chlorine gas in the mixed solution. Further, it further comprises a micro-mixer 13 for mixing N-o-tolylthiourea and glacial acetic acid, a gas-liquid separation tank 14, a secondary reaction kettle 15 which has the same structure as the primary reaction kettle 1, and a glacial acetic acid heater 12 for cooling the material, the primary reaction kettle 1 and the secondary reaction kettle 15 are both provided with a feeding pipe 151 and a discharging pipe 152, after the N-o-tolylthiourea and the pre-cooled glacial acetic acid are preliminarily mixed in the micro-mixer 13, the mixed solution is continuously reacted by introducing chlorine gas in the primary reaction kettle 1 and the secondary reaction kettle 15, and then 2-amino-4-methylbenzothiazole solution is prepared through the gas-liquid separation tank 14, and an S-shaped pipe 11 is arranged between the feeding end of the feeding pipe 151 of the primary reaction kettle 1 and the discharging end of the micro-mixer 13.

[0025] The chemical reaction speed of N-o-tolylthiourea and chlorine gas is fast at a low temperature, and the reaction of N-o-tolylthiourea and chlorine gas is strong in single at a low temperature, thereby effectively improving the product quality, so that the glacial acetic acid needs to be pre-cooled before use; the pre-cooled glacial acetic acid and N-o-tolylthiourea are sent into the micro-mixer 13 to be initially homogenized to form a mixed solution, and an exothermic reaction occurs in the mixing process, so that the reaction heat can be taken away in time by freezing brine cooling in the equipment inside and the jacket part of the micro-mixer 13, so as to avoid affecting the material reaction, and the cooling mode is the prior art, which will not be described in detail here. In addition, an S-shaped pipe 11 is arranged between the feeding end of the feeding pipe 151 of the first reaction kettle 1 and the discharging end of the micro-mixer 13, which can further mix and react the materials in a limited space. The mixed solution enters the bottom of the first reaction kettle 1 through the feeding pipe 151, and the driving mechanism 3 drives the stirring mechanism 2 to stir when the first reaction kettle 1 operates. The chlorine gas injection mechanism 4 uniformly spreads the chlorine gas at the bottom of the first reaction kettle 1 and mixes with the mixed solution raw material at the bottom of the first reaction kettle 1. The contact area between chlorine gas and the mixed solution is increased, and the sieve plate assembly can slow down the rising speed of chlorine gas in the mixed solution, so that chlorine gas has sufficient time to react with the mixed solution. After the unreacted chlorine gas moves to the upper side of the inside of the first reaction kettle 1, the gas suction mechanism 5 recovers and reuses the unreacted chlorine gas, effectively improves the utilization rate of chlorine gas, and reduces the production and processing cost. The first reaction liquid enters the second reaction kettle 15 through the discharging pipe 152 of the first reaction kettle 1 for deep chlorination, and finally the reaction liquid enters the gas-liquid separation tank 14 to obtain a high-purity 2-amino-4-methylbenzothiazole solution. By mixing glacial acetic acid instead of dichloroethane with N-o-tolylthiourea, the problem that the reaction material is relatively viscous after the traditional process of mixing dichloroethane with chlorine gas and N-o-tolylthiourea is avoided, and only an intermittent reaction kettle can be used for reaction production. The multi-stage reaction kettle is used for continuous operation to eliminate downtime, thereby solving the problem of low production efficiency caused by repeated heating and cooling of the intermittent reaction kettle in the traditional process, effectively improving the production and processing efficiency of the product; and the mechanical linkage between the mechanisms and the fluid dynamics are optimized, the problem of low gas-liquid reaction efficiency in a high-viscosity system is solved, and an innovative engineering example is provided for continuous production of pesticide intermediates.

[0026] As Figure 1 , Figure 2 , Figure 8 and Figure 9As shown, as a preferred embodiment, on the basis of the above manner, further, the stirring mechanism 2 comprises a stirring pipe 201 rotatably connected in the primary reactor 1 and a stirring component 202 arranged outside the stirring pipe 201, and the driving mechanism 3 comprises a mounting seat 301 fixed on the top of the primary reactor 1, a driving motor 302 fixed on the mounting seat 301, a driving gear 303 connected with the output shaft of the driving motor 302, and a driven gear 304 arranged on the stirring pipe 201 and engaged with the driving gear 303; The driving motor 302 drives the driving gear 303 to rotate through the output shaft, the driving gear 303 is engaged with the driven gear 304 fixed on the stirring pipe 201, the torque is transmitted to the stirring pipe 201, the stirring pipe 201 drives the stirring component 202 to stir and mix the mixed solution and the chlorine gas, the stirring component 202 is a prior art, which is not described here, the stirring component 202 forms a radial / axial composite flow field, effectively breaks the bubbles, increases the gas-liquid contact area, and makes the chlorine gas fully react with the mixed solution.

[0027] As shown in Figure 1 , Figure 2 , Figure 8 , Figure 9 and Figure 10 , as a preferred embodiment, on the basis of the above manner, further, the gas extraction mechanism 5 comprises an exhaust pipe 501 fixedly connected with the mounting seat 301, a one-way air inlet pipe 502 arranged between the exhaust pipe 501 and the inner cavity of the primary reactor 1, and an exhaust assembly arranged in the exhaust pipe 501 and connected with the driving mechanism 3; Further, the exhaust assembly comprises a first connecting plate 3021 connected with the output shaft of the driving motor 302, a second connecting plate 3022 movably connected with the first connecting plate 3021, a slide rod 3023 movably connected with the second connecting plate 3022, an elastic telescopic rod 3024 fixedly connected with the slide rod 3023, and a piston 3025 connected with the end of the elastic telescopic rod 3024 away from the slide rod 3023, the piston 3025 is slidably connected in the exhaust pipe 501, and a one-way exhaust pipe 503 is further connected to the exhaust pipe 501, the end of the one-way exhaust pipe 503 away from the exhaust pipe 501 is connected with the chlorine gas injection mechanism 4; The driving motor 302 drives the first connecting plate 3021 to rotate through the output shaft, which is converted into the linear reciprocating motion of the slide rod 3023 through the second connecting plate 3022, the elastic telescopic rod 3024 drives the piston 3025 to reciprocate in the exhaust pipe 501, when the piston 3025 moves to the right, it sucks the unreacted chlorine gas at the top of the reactor through the one-way air inlet pipe 502, when the piston 3025 moves to the left, it delivers the chlorine gas to the chlorine gas injection mechanism 4 through the one-way exhaust pipe 503 for recycling, thereby improving the utilization rate of chlorine gas, and the piston 3025 and the inner wall of the exhaust pipe 501 are sealed by PTFE composite material, which is resistant to chlorine corrosion; And need to explain, the slide bar 3023 and the piston 3025 between the setting elastic telescopic rod 3024, can avoid because the kettle pressure changes, the piston 3025 cannot be effectively pulled, when the elastic telescopic rod 3024 automatically changes, to adapt to the first connecting plate 3021 and the second connecting plate 3022 activity.

[0028] As Figure 2 , Figure 5 , Figure 7 , Figure 8 And Figure 10 As shown in the preferred embodiment, on the basis of the above-mentioned manner, further, the chlorine injection mechanism 4 includes a gas guide pipe 401 arranged in the stirring pipe 201, a valve body 402 rotatably connected to the top of the gas guide pipe 401, a spiral hose 403 connected to the end of the gas guide pipe 401 away from the valve body 402, and an aeration plate 404 connected to the spiral hose 403, the aeration plate 404 is provided with a plurality of aeration heads, the spiral hose 403 is automatically telescopic with the movement of the aeration plate 404 and orderly wound around the reciprocating screw rod 601, avoiding the spiral hose 403 from being entangled with the reciprocating screw rod 601 or the aeration plate 404; Further, the valve body 402 is provided as a three-way valve, two interfaces of the three-way valve are respectively connected with the one-way exhaust pipe 503 and the gas guide pipe 401, and the remaining one interface is connected with a gas supply pipe 4021, the end of the gas supply pipe 4021 away from the three-way valve is connected with a chlorine supply device; The chlorine supply device is a prior art, which will not be described in detail here, the chlorine supply device inputs fresh air into the kettle body through the gas supply pipe 4021, the three-way valve adjusts the mixing ratio of fresh chlorine in the gas supply pipe 4021 and recycled chlorine in the one-way exhaust pipe 503 in real time, then the gas guide pipe 401 delivers chlorine to the rotating aeration plate 404, and generates 0.5-1mm diameter bubbles through the microporous aeration head to chlorinate the mixed solution; it should be noted that the top of the gas guide pipe 401 can be rotatably connected to the valve body 402 through a rotating joint or other components to cooperate with the displacement of the gas guide pipe 401 with the stirring pipe 201.

[0029] As Figure 2 And Figure 7 As shown in the preferred embodiment, on the basis of the above-mentioned manner, further, the chlorine injection mechanism 4 further includes a protective shell 6 fixedly connected to the bottom of the stirring pipe 201, the reciprocating screw rod 601 is rotatably connected in the protective shell 6, the sleeve 602 connected to the aeration plate 404 is threadedly connected to the reciprocating screw rod 601, the top of the protective shell 6 is provided with an opening, the fixed plate 7 is rotatably connected to the top opening of the protective shell 6, the fixed plate 7 is fixedly connected to the inner wall of the primary reactor 1 through a connecting plate, the fixed bevel gear 701 is fixedly arranged on the lower side of the fixed plate 7, and the movable bevel gear 6011 meshing with the fixed bevel gear 701 is arranged on the reciprocating screw rod 601; When the driving motor 302 drives the stirring pipe 201 to rotate, the movable bevel gear 6011 moving with the stirring pipe 201 meshes with the fixed bevel gear 701 and drives the reciprocating screw rod 601, so that the sleeve 602 drives the aeration plate 404 to move along the reciprocating screw rod 601. The protective shell 6 should be provided with a guide rod for limiting the axial movement of the sleeve 602 along the reciprocating screw rod 601. The guide rod is a prior art and will not be described here. The aeration plate 404 expands or shrinks in a circular spiral track, thereby dispersing chlorine gas at the bottom of the reactor, increasing the aeration range of the aeration head of the aeration plate 404, and enabling chlorine gas to fully react with the mixed solution. The fixed plate 7 and the protective shell 6 can protect the transmission bevel gear. It should be noted that titanium alloy (such as TA2 / TA9) or hastelloy (C276) should be preferred as the material of the screw rod and the sleeve 602, which can remain stable in a mixed solution containing halogen ions such as Cl⁻ and Br⁻. If the pH value of the solution is less than 4 or greater than 10, a coating should be added to reduce the friction coefficient and isolate chemical corrosion. The gap between the screw rod and the sleeve 602 should be controlled within 20-50 μm. Double mechanical seals (made of silicon carbide / graphite) are used to prevent solution from seeping in. If necessary, a magnetic coupling transmission device can be used to completely isolate the solution contact risk through non-contact transmission. Double mechanical seals and magnetic coupling transmission are prior arts and will not be described here.

[0030] As shown in Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 , as a preferred embodiment, on the basis of the above-mentioned mode, further, the sieve plate assembly comprises a spherical shell 8 and a sieve plate body 801 arranged outside the spherical shell 8. The bottom of the sieve plate body 801 is slidably connected with a movable block 805. The movable block 805 is movably connected with an active rod 802 through a pin shaft. The end of the active rod 802 away from the sieve plate body 801 is movably connected with a sliding block 803. The inner wall of the primary reactor 1 is provided with a wave track groove 9 matched with the sliding block 803. The bottom of the sieve plate body 801 is provided with a sliding groove 8011 for sliding of the movable block 805. The outer side of the stirring pipe 201 is fixedly connected with a spherical joint 10 slidably connected with the spherical shell 8. The outer side of the spherical joint 10 is fixedly connected with a limiting block 1001. The inner wall of the spherical shell 8 is provided with a limiting groove 804 for sliding of the limiting block 1001. When the stirring pipe 201 rotates, the spherical joint 10 rotates, the spherical joint 10 drives the sieve plate body 801 to rotate through the limiting block 1001, and the wave track groove 9 cooperates with the sliding block 803 to make the sieve plate body 801 reciprocatingly tilt and swing up and down, so that the path of the chlorine gas bubbles is forced to be tortuous in the rising process, a dynamic flow resistance process is formed, the residence time of the bubbles in the mixed solution is prolonged, the chlorine gas is fully reacted with the mixed solution, the reciprocating displacement aeration plate 404 and the swinging sieve plate body 801 can form shear turbulent flow, the solution with excessively high viscosity can be treated, the problem that the material viscosity leads to uneven mixing is avoided, and the product processing quality is improved.

[0031] The application further discloses a continuous reaction method for producing 2-amino-4-methylbenzothiazole. S1: preliminary mixing of raw materials: the pre-cooled glacial acetic acid and N-o-tolylthiourea are sent into the micro-mixer 13 to be initially homogenized to form a mixed solution; S2: first-stage continuous chlorination reaction: the mixed solution is fed into the bottom of the first-stage reaction kettle 1 through the feeding pipe 151; dynamic chlorine injection: the driving motor 302 drives the stirring pipe 201 to rotate, the movable bevel gear 6011 meshes with the fixed bevel gear 701 to drive the reciprocating lead screw 601, the sleeve 602 drives the aeration plate 404 to move along the reciprocating lead screw 601, the aeration plate 404 expands or shrinks in a circular spiral track, and then the chlorine gas is dispersed in the kettle bottom, and the aeration range of the aeration head of the aeration plate 404 is increased; S3: sieve plate cooperative movement: the stirring pipe 201 drives the sieve plate body 801 to rotate through the spherical joint 10, and the wave track groove 9 cooperates with the sliding block 803 to make the sieve plate body 801 reciprocatingly tilt and swing up and down, so that the path of the chlorine gas bubbles is forced to be tortuous in the rising process, and a dynamic flow resistance process is formed to prolong the residence time of the bubbles in the mixed solution; S4: synchronous pumping and regeneration: the driving motor 302 drives the piston 3025 to reciprocate in the pumping pipe 501 through the first connecting plate 3021 and the second connecting plate 3022; when the piston 3025 moves to the right, the unreacted chlorine gas at the top of the kettle is sucked through the one-way air inlet pipe 502; when the piston 3025 moves to the left, the chlorine gas is extruded and returned to the three-way valve body 402 through the one-way air outlet pipe 503, mixed with the newly supplemented chlorine gas and then injected into the reaction area in the kettle body again; S5: second-stage continuous reaction and product separation: the first-stage reaction liquid is fed into the second-stage reaction kettle 15 through the discharging pipe 152 to be deeply chlorinated; the final reaction liquid is fed into the gas-liquid separation tank 14, and high-purity 2-amino-4-methylbenzothiazole solution is obtained through separation.

[0032] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent substitutions or changes according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A continuous reaction apparatus for the production of 2-amino-4-methylbenzothiazole comprising a primary reactor (1), characterized in that, Also include: Stirring mechanism (2), the stirring mechanism (2) is arranged in the primary reactor (1), for stirring the chlorine and mixed solution in the primary reactor (1); Driving mechanism (3), the driving mechanism (3) is arranged at the top of the primary reactor (1), for driving the stirring mechanism (2) in the primary reactor (1) does stirring action; Chlorine injection mechanism (4), the chlorine injection mechanism (4) is connected with the stirring mechanism (2), for the chlorine is evenly distributed in the primary reactor (1); And air extraction mechanism (5), the air extraction mechanism (5) is arranged at the top of the primary reactor (1) and is connected with the driving mechanism (3), for the chlorine that is not reacted in the primary reactor (1) is recycled and reused; Wherein, the primary reactor (1) is sequentially arranged from top to bottom with a plurality of sieve plate assemblies connected with the stirring mechanism (2), for slowing down the rising speed of chlorine in the mixed solution.

2. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 1, characterized by The stirring mechanism (2) includes a stirring pipe (201) rotatably connected in the primary reactor (1) and a stirring part (202) arranged outside the stirring pipe (201), the driving mechanism (3) includes a mounting seat (301) fixedly arranged at the top of the primary reactor (1), a driving motor (302) fixedly arranged on the mounting seat (301), a driving gear (303) connected with the output shaft of the driving motor (302) and a driven gear (304) arranged on the stirring pipe (201) and engaged with the driving gear (303).

3. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 2, characterized by The air extraction mechanism (5) includes an exhaust pipe (501) fixedly connected with the mounting seat (301), a one-way air inlet pipe (502) arranged between the exhaust pipe (501) and the inner cavity of the primary reactor (1) and an exhaust assembly arranged in the exhaust pipe (501) and connected with the driving mechanism (3).

4. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 3, characterized by The exhaust assembly includes a first connecting plate (3021) connected with the output shaft of the driving motor (302), a second connecting plate (3022) movably connected with the first connecting plate (3021), a slide rod (3023) movably connected with the second connecting plate (3022), an elastic telescopic rod (3024) fixedly connected with the slide rod (3023) and a piston (3025) connected with the end of the elastic telescopic rod (3024) away from the slide rod (3023), the piston (3025) is slidably connected in the exhaust pipe (501), and a one-way exhaust pipe (503) is further connected to the exhaust pipe (501), and the end of the one-way exhaust pipe (503) away from the exhaust pipe (501) is connected with the chlorine injection mechanism (4).

5. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 4, characterized by The chlorine injection mechanism (4) includes a gas guide pipe (401) arranged in the stirring pipe (201), a valve body (402) rotatably connected with the top of the gas guide pipe (401), a spiral hose (403) connected with the end of the gas guide pipe (401) away from the valve body (402) and an aeration plate (404) connected with the spiral hose (403), and a plurality of aeration heads are arranged on the aeration plate (404).

6. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 5, wherein The valve body (402) is provided as a three-way valve, two interfaces of which are connected with a one-way exhaust pipe (503) and a gas guide pipe (401) respectively, and the remaining one interface is connected with a gas supply pipe (4021), and the end of the gas supply pipe (4021) away from the three-way valve is connected with a chlorine gas supply device.

7. A continuous reaction apparatus for the production of 2-amino-4-methylbenzothiazole according to claim 6, characterized by The chlorine injection mechanism (4) further comprises a protective shell (6) fixedly connected with the bottom of the stirring pipe (201), a reciprocating screw rod (601) is rotatably connected in the protective shell (6), a sleeve (602) connected with the aeration plate (404) is threadedly connected on the reciprocating screw rod (601), an opening is formed in the top of the protective shell (6), a fixed plate (7) is rotatably connected with the top opening of the protective shell (6), the fixed plate (7) is fixedly connected with the inner wall of the primary reactor (1) through a connecting plate, a fixed bevel gear (701) is fixedly arranged on the lower side of the fixed plate (7), and a movable bevel gear (6011) meshing with the fixed bevel gear (701) is arranged on the reciprocating screw rod (601).

8. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 7, characterized by The sieve plate assembly comprises a spherical shell (8) and a sieve plate body (801) arranged outside the spherical shell (8), a movable block (805) is slidably connected with the bottom of the sieve plate body (801), the movable block (805) is movably connected with an movable rod (802) through a pin shaft, a sliding block (803) is movably connected with the end of the movable rod (802) away from the sieve plate body (801), a wave track groove (9) matched with the sliding block (803) is formed in the inner wall of the primary reactor (1), a sliding groove (8011) for sliding of the movable block (805) is formed in the bottom of the sieve plate body (801), a spherical joint (10) slidably connected with the spherical shell (8) is fixedly arranged outside the stirring pipe (201), a limiting block (1001) is fixedly arranged outside the spherical joint (10), and a limiting groove (804) for sliding of the limiting block (1001) is formed in the inner wall of the spherical shell (8).

9. A continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 8, characterized by Further comprising a micro-mixer (13), a gas-liquid separation tank (14), a secondary reactor (15) which has the same structure as the primary reactor (1), and an ice acetic acid cooler (12) for cooling the material, the primary reactor (1) and the secondary reactor (15) are both provided with a feeding pipe (151) and a discharging pipe (152), N-o-tolylthiourea and pre-cooled ice acetic acid are preliminarily mixed in the micro-mixer (13), the mixed solution is continuously reacted with chlorine in the primary reactor (1) and the secondary reactor (15), and then 2-amino-4-methylbenzothiazole solution is prepared through the gas-liquid separation tank (14), and an S-shaped pipe (11) is arranged between the feeding end of the feeding pipe (151) of the primary reactor (1) and the discharging end of the micro-mixer (13).

10. A continuous reaction method for producing 2-amino-4-methylbenzothiazole, which is processed using the continuous reaction apparatus for producing 2-amino-4-methylbenzothiazole according to claim 9, characterized by, The method comprises the following steps: S1: preliminary mixing of raw materials: pre-cooled ice acetic acid and N-o-tolylthiourea are sent into the micro-mixer (13) for preliminary homogenization to form a mixed solution; S2: primary continuous chlorination reaction: the mixed solution enters the bottom of the primary reactor (1) through the feeding pipe (151); Dynamic chlorine injection: the driving motor (302) drives the stirring tube (201) to rotate, and through the meshing of the movable bevel gear (6011) and the fixed bevel gear (701), the reciprocating screw rod (601) is driven to move, so that the sleeve (602) drives the aeration plate (404) to move along the reciprocating screw rod (601), and the aeration plate (404) expands or shrinks in a circular spiral track, and then the chlorine gas is dispersed in the kettle bottom, and the aeration range of the aeration head of the aeration plate (404) is increased; S3: screen plate cooperative movement: the stirring tube (201) drives the screen plate body (801) to rotate through the spherical joint (10), and at the same time, the wave track groove (9) cooperates with the sliding block (803) to make the screen plate body (801) reciprocate and tilt up and down, so that the chlorine gas bubble path is forced to be tortuous during the rising process, and a dynamic flow resistance process is formed, and the residence time of the bubbles in the mixed solution is prolonged; S4: synchronous pumping and regeneration: the driving motor (302) drives the piston (3025) to reciprocate in the pumping pipe (501) through the first connecting plate (3021) and the second connecting plate (3022); When the piston (3025) moves to the right, the unreacted chlorine gas at the top of the kettle is sucked through the one-way air inlet pipe (502); When the piston (3025) moves to the left, the chlorine gas is extruded and returned to the three-way valve body (402) through the one-way exhaust pipe (503), and then mixed with the newly supplemented chlorine gas and injected into the reaction zone inside the kettle body again; S5: secondary continuous reaction and product separation: the primary reaction liquid enters the secondary reaction kettle (15) through the discharge pipe (152) for deep chlorination; The final reaction liquid enters the gas-liquid separation tank (14), and high-purity 2-amino-4-methylbenzothiazole solution is obtained by separation.

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