Intelligent flow reactor and method for high-yield continuous synthesis of piperidine

Abstract

The invention relates to the technical field of reactors, and discloses an intelligent flow reactor and method for high-yield continuous synthesis of piperonylamine, the intelligent flow reactor for high-yield continuous synthesis of piperonylamine comprises a left support sleeve, and also comprises a round sleeve and an interlayer shell which are fixedly connected with the left support sleeve, the multiple blocking strips and the diameter changing strips are attached to the outer wall of the synthesis pipe and are the same in radian, a micro-channel is formed between each blocking strip and the corresponding diameter changing strip and the synthesis pipe, and the shaft disc changes the flow path of the micro-channel through the blocking strips and the diameter changing strips. The barrier strips and the diameter changing strips are driven by the shaft disc to rotate, the flowing path of fluid can be optimized according to reaction requirements, the length and the width of a reaction channel are adjusted, resistance is changed to control the flow speed change of reaction liquid, and the phenomena of local stagnation and uneven flowing are effectively avoided; in cooperation with actions of the barrier strip and the diameter changing strip, reaction process conversion can be realized without interruption of production, and the production effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of reactors, and particularly to an intelligent flow reactor and method for continuous synthesis of piperonylamine with high yield. Background Art

[0002] As an important organic compound in the fields of medicine, pesticides, etc., the synthesis of piperonylamine usually utilizes an intelligent flow reactor, that is, through the microchannels inside the reactor, mainly relying on the advantages of mass transfer and heat transfer, precise reaction control and continuous production of the microchannel reactor.

[0003] However, in the prior art, the reaction channels of existing traditional reactors usually adopt a fixed-length design. Once manufactured, it is difficult to change the internal flow channel structure. In actual production requirements, when it is necessary to extend the reaction channel length according to the reaction conditions of the reaction liquid to meet the longer reaction path and reaction medium residence time required by specific chemical reactions, the existing reactors can only be achieved by increasing the overall equipment size and extending the shell length. This not only seriously reduces the utilization rate of the production space, but also leads to a significant increase in the costs of equipment manufacturing, installation and commissioning, and long-term maintenance. It is not only extremely difficult to implement and costly, but also easily restricted by the original site, and will also cause the production line to stop for a long time, making it extremely difficult to improve the reactor subsequently. In terms of reaction process control, due to different requirements of chemical reactions for fluid flow state and heat transfer efficiency, the existing reactors cannot be flexibly adjusted according to the dynamic changes of reaction conditions. Taking the nitration reaction of piperonylamine as an example, the size of its flow channel length is single, resulting in easy occurrence of local stagnation or uneven flow of the fluid in the reactor, causing the imbalance of the reactant distribution, making it difficult to achieve rapid and efficient heat dissipation, and easily leading to too high local temperature, which not only causes side reactions and poses safety hazards, but also, due to the fixed flow channel structure being unable to optimize the fluid flow path, the uneven distribution will cause overreaction in some areas or insufficient reaction in some areas, seriously affecting the overall performance of the reaction and the stability of product quality. Summary of the Invention

[0004] The purpose of the present invention is to provide an intelligent flow reactor and method for continuous synthesis of piperonylamine with high yield, so as to solve the problem that the reaction channels of the reactor affect the reaction of the reaction liquid.

[0005] On the one hand, the present invention provides an intelligent flow reactor for continuously synthesizing piperidineamine with high yield, which includes a left support sleeve, and also includes a circular sleeve and a sandwich shell fixedly connected to the left support sleeve, a right support sleeve fixedly connected to one end of the sandwich shell, a material distribution member fixedly connected to the circular sleeve, a shaft disc rotatably connected inside the material distribution member, a synthesis tube arranged inside the right support sleeve, a barrier strip and a diameter-changing strip fixedly connected to the left end of the shaft disc, and an inner sleeve shell located inside the synthesis tube and fixedly connected to the right support sleeve. The inner sleeve shell is fixedly connected to the inside of the right support sleeve, the right support sleeve fits with the shaft disc, the barrier strip and the diameter-changing strip are arranged at equal angles in multiple numbers, and multiple barrier strips and diameter-changing strips all fit with the outer wall of the synthesis tube and have the same radian. A microchannel is formed between a single barrier strip and the synthesis tube, and the shaft disc changes the flow path of the microchannel through the barrier strip and the diameter-changing strip.

[0006] Further, a reaction module is arranged on the surface of the synthesis tube. The reaction module includes multiple groups of reaction modules connected end to end. The reaction module includes a straight arc plate, a double-channel plate, a single-channel plate, a long arc strip, and a short arc strip. The straight arc plate is located on the left side of the double-channel plate and the single-channel plate, the long arc strip is located between the single-channel plate and the double-channel plate, and the short arc strip is located between the barrier strip and the double-channel plate.

[0007] Further, a sealing strip and a blocking strip are fixedly connected to the barrier strip. When the barrier strip fits with the double-channel plate, it is in the initial position.

[0008] Further, a connecting strip and a splicing strip are fixedly connected to the diameter-changing strip. The connecting strip fits with the left end of the single-channel plate, the splicing strip fits with the right end of the single-channel plate. The distance between the diameter-changing strip and the straight arc plate is greater than the distance between the connecting strip and the double-channel plate. The sealing strip is located on the left side of the connecting strip, and the blocking strip is located on the right side of the splicing strip.

[0009] Further, there are multiple reaction modules, and they are arranged on the outer tube wall of the synthesis tube in an equiangular array centered on the center of the synthesis tube. Multiple aggregate plates are arranged at equal angles on the right outer wall of the synthesis tube, and the right side of the aggregate plate is the aggregate area.

[0010] Further, multiple closing blocks are arranged outside the synthesis tube. Both the double-channel plate and the barrier strip are provided with short arc openings, and the short arc strip is located in the two short arc openings. Both the double-channel plate and the single-channel plate are provided with long arc openings, and the long arc strip is located in the two long arc openings. When the connecting strip fits with the double-channel plate, the midline of the distance between the double-channel plate and the barrier strip coincides with the midline of the short arc strip.

[0011] Further, the material distribution member includes a material distribution ring arranged inside the circular sleeve, and a guide plate fixedly connected to the material distribution ring. The guide plate is fixedly connected to the circular sleeve, and multiple guide openings are arranged at equal angles on the guide plate.

[0012] Further, the shaft disc includes a rotating shaft rotatably connected inside the circular sleeve, and a disc fixedly connected to one end of the rotating shaft. The other end of the rotating shaft extends outside the left support sleeve. A plurality of guiding grooves are equiangularly formed on the disc. The material guiding port communicates with the guiding grooves, and the guiding grooves communicate with the microchannels and have the same number.

[0013] Further, a feed port and a discharge port are respectively fixedly connected to the top and bottom of the sandwich shell. The feed port communicates with the inside of the material distribution ring, and the discharge port communicates with the aggregate area. An inner water inlet and an outer water inlet are fixedly connected to one side of the circular sleeve. A conduit is fixedly connected to the inner sleeve shell. The conduit penetrates through the arc-shaped port and is connected to the inner water inlet. The outer water inlet is connected to the inside of the sandwich of the sandwich shell.

[0014] On the other hand, the present invention provides: a method for continuously synthesizing piperonalamine with high yield, using an intelligent flow reactor for continuously synthesizing piperonalamine with high yield, including the following steps: Step 1: Dissolve piperonal in an organic solvent to form a homogeneous reaction solution.

[0015] Step 2: Transport it into the inside of the material distribution part at a stable flow rate through a metering pump, and then enter the microchannels on the surface of the synthesis tube, so that the reaction solution fully contacts and reacts.

[0016] Step 3: Adjust the reaction temperature inside the synthesis tube through an external heating or cooling device.

[0017] Step 4: Drive the barrier strip and the diameter-changing strip according to requirements by using the shaft disc, so as to adjust the channel length and size, change the flow rate and affect the residence time of the reaction solution in the microchannels.

[0018] Step 5: First evaporate and remove the low-boiling organic solvent and unreacted raw materials, and then obtain a high-purity piperonalamine product through methods such as vacuum distillation.

[0019] The beneficial effects of the present invention: 1. By driving the barrier strip and the diameter-changing strip to rotate with the shaft disc, the flow path of the fluid can be optimized according to the reaction requirements, the length and width of the reaction channel can be adjusted, the resistance can be changed to control the flow rate change of the reaction solution, effectively avoiding local stagnation and uneven flow phenomena, making the distribution of reactants more uniform. At the same time, using a single drive to control the rotation of the shaft disc, cooperating with the actions of the barrier strip and the diameter-changing strip, the reaction process conversion can be realized without interrupting production, improving the production effect.

[0020] 2. By the rotational offset of the barrier strip and the diameter-changing strip, in cooperation with the straight-arc plate, double-channel plate, and single-channel plate fixed to the surface of the synthesis tube, the length, cross-sectional shape, and flow path of the microchannel can be quickly changed. This purely mechanical structural design, without complex control, can achieve the switching and adjustment of the reaction path within seconds only through the relative movement of mechanical components, meeting the different requirements for residence time, flow rate, and mixing effect in different reaction stages, reducing the equipment transformation cost and difficulty, and not causing long-term shutdown of the production line, providing convenience for the continuous production of piperonylamine.

[0021] 3. By forming an annular material distribution through the material distribution part, the uniform distribution and low-resistance introduction of the reaction liquid are realized. At the same time, the double-layer heat exchange structure composed of the sandwich shell and the inner sleeve shell can accurately control the reaction temperature through the internal and external circulating coolant channels, enabling the entire synthesis process to operate continuously and stably. Description of the Drawings

[0022] Figure 1 is a first perspective three-dimensional structural schematic diagram of the intelligent flow reactor of the present invention; Figure 2 is a structural schematic diagram of the synthesis tube of the present invention; Figure 3 is a structural schematic diagram of the material distribution ring and the shaft disc of the present invention; Figure 4 is of the present invention Figure 2 an enlarged schematic diagram of part A in; Figure 5 is a top view of the overall structure of the intelligent flow reactor of the present invention; Figure 6 is of the present invention Figure 5 a cross-sectional view taken along line B-B in; Figure 7 is a structural schematic diagram of the disc of the present invention; Figure 8 is a structural schematic diagram of the circular sleeve of the present invention; Figure 9 is a state diagram of the movement of the diameter-changing strip and the barrier strip of the present invention.

[0023] In the figure: 1. Left support sleeve; 2. Circular sleeve; 21. Inner water inlet; 22. Outer water inlet; 3. Interlayer shell; 31. Feed inlet; 32. Discharge outlet; 4. Right support sleeve; 5. Material distribution part; 51. Material distribution ring; 52. Guide plate; 501. Guide opening; 6. Shaft disc; 61. Rotating shaft; 62. Disc; 621. Guide groove; 601. Arc-shaped opening; 7. Synthesis tube; 71. Straight arc plate; 72. Double-channel plate; 73. Single-channel plate; 74. Long arc strip; 75. Short arc strip; 701. Aggregate plate; 702. Aggregate area; 8. Barrier strip; 81. Seal strip; 82. Barrier strip; 9. Diameter-changing strip; 91. Connecting strip; 92. Fitting strip; 10. Inner sleeve shell; 101. Conduit; 11. Sealing block; 12. Short arc opening; 13. Long arc opening. Specific embodiments

[0024] To make the above objects, features, and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings of the specification.

[0025] Example 1. Refer to Figures 1-9 , which is the first embodiment of the present invention, and provides an intelligent flow reactor for the continuous synthesis of piperidineamine with high yield. It includes a left support sleeve 1, and also includes a circular sleeve 2 and an interlayer shell 3 fixedly connected to the left support sleeve 1, a right support sleeve 4 fixedly connected to one end of the interlayer shell 3, a material distribution part 5 fixedly connected to the circular sleeve 2, a shaft disc 6 rotatably connected inside the material distribution part 5, a synthesis tube 7 arranged inside the right support sleeve 4, a barrier strip 8 and a diameter-changing strip 9 fixedly connected to the left end of the shaft disc 6, and an inner sleeve shell 10 located inside the synthesis tube 7 and fixedly connected to the right support sleeve 4. The inner sleeve shell 10 is fixedly connected to the inside of the right support sleeve 4, the right support sleeve 4 is in contact with the shaft disc 6. A plurality of barrier strips 8 and diameter-changing strips 9 are arranged at equal angles. A plurality of barrier strips 8 and diameter-changing strips 9 are all in contact with the outer wall of the synthesis tube 7 and have the same curvature. A microchannel is formed between a single barrier strip 8 and the diameter-changing strip 9 and the synthesis tube 7. The shaft disc 6 changes the flow path of the microchannel through the barrier strip 8 and the diameter-changing strip 9.

[0026] Among them, the shaft disc 6 can be driven by a stepping motor. At the same time, the stepping motor needs to be paired with a microstepping driver, which can further subdivide the step angle to achieve rotation at different angles such as five degrees or ten degrees. It can also be replaced by a pulse servo motor. At the same time, an interlayer is provided inside the interlayer shell 3, and a coolant or heating medium can be introduced between the interlayer and the inner sleeve shell 10 and the synthesis tube 7 to control the reaction temperature. At the same time, the circular sleeve 2 and the interlayer shell 3 can be directly welded by laser cladding technology, so that there are no defects such as pores and cracks on the joint surface.

[0027] Refer to Figures 1-3, a reaction module is arranged on the surface of the synthesis tube 7. The reaction module includes multiple groups of reaction modules connected end to end. The reaction module includes a straight arc plate 71, a double-channel plate 72, a single-channel plate 73, a long arc strip 74, and a short arc strip 75. The straight arc plate 71 is located on the left side of the double-channel plate 72 and the single-channel plate 73. The long arc strip 74 is located between the single-channel plate 73 and the double-channel plate 72. The short arc strip 75 is located between the barrier strip 8 and the double-channel plate 72.

[0028] Specifically, the radian of the straight arc plate 71 matches and fits the inner wall of the sandwich shell 3. The double-channel plate 72, the single-channel plate 73, the long arc strip 74, and the short arc strip 75 also closely fit the sandwich shell 3 to ensure sufficient sealing effect. A channel is formed between the double-channel plate 72 and the single-channel plate 73, and another channel is formed again between the double-channel plate 72 and the barrier strip 8. Thus, there are flow channels on both sides of the single-channel plate 73.

[0029] Refer to Figures 2-4 , a seal strip 81 and a blocking strip 82 are fixedly connected to the barrier strip 8. When the barrier strip 8 fits with the double-channel plate 72, the barrier strip 8 is in the initial position, so that the channel between the double-channel plate 72 and the barrier strip 8 is blocked. At this time, the reaction liquid will only flow through the double-channel plate 72 and the single-channel plate 73. At this time, the reaction liquid passes through this microchannel in a laminar flow state and stays in the synthesis tube 7 for about 80 s.

[0030] Refer to Figures 2-5 , a connecting strip 91 and a splicing strip 92 are fixedly connected to the diameter-changing strip 9. The connecting strip 91 fits with the left end of the single-channel plate 73, and the splicing strip 92 fits with the right end of the single-channel plate 73 to ensure sealing. The distance between the diameter-changing strip 9 and the straight arc plate 71 is greater than the distance between the connecting strip 91 and the double-channel plate 72. The seal strip 81 is located on the left side of the connecting strip 91, and the blocking strip 82 is located on the right side of the splicing strip 92. At the same time, the double-channel plate 72 is located between the barrier strip 8 and the single-channel plate 73.

[0031] Specifically, when the shaft disc 6 rotates, the barrier strip 8 and the diameter-changing strip 9 will rotate synchronously with it, and their positions will also change accordingly. At this time, the barrier strip 8 will drive the seal strip 81 and the blocking strip 82 to move synchronously, and the diameter-changing strip 9 will drive the connecting strip 91 and the splicing strip 92 to move synchronously. Taking the barrier strip 8 in the initial position as an example, assuming that the shaft disc 6 rotates six degrees at this time, the diameter-changing strip 9 will approach the straight arc plate 71 to reduce the gap between the two, and the connecting strip 91 and the splicing strip 92 will directly fit with the double-channel plate 72 to block the passage between the double-channel plate 72 and the single-channel plate 73. At this time, the barrier strip 8 no longer fits with the double-channel plate 72, thus extending the path. The reaction liquid can only pass through the path between the barrier strip 8 and the double-channel plate 72. At the same time, the distance between the diameter-changing strip 9 and the straight arc plate 71 is reduced to enhance the mixing degree, so that the cross-sectional area of the flow channel changes continuously, thereby realizing the precise control of the fluid flow rate and residence time. The reaction time is about 120 s.

[0032] In addition, the shaft disc 6 can also be controlled to rotate by three degrees. While narrowing the distance between the diameter-changing strip 9 and the straight arc plate 71, the passage between the double-channel plate 72 and the single-channel plate 73 can also be opened simultaneously to form a double path, which converges again at the next passage, enhancing the reaction effect. Shunting can be achieved, dispersing the reaction heat into two channels, reducing the heat load in a single channel, making the reaction temperatures in the two channels more uniform. When re-converging, the uniform fluid mixing avoids local overheating, improving the safety and quality of the reaction solution, enabling the reaction solution to quickly pass through the two channels after shunting, mainly used to shorten the residence time of the reaction solution. When it is necessary to extend the reaction time and strengthen the mixing degree simultaneously, the channel between the barrier strip 8 and the double-channel plate 72 can be directly utilized.

[0033] Among them, when the barrier strip 8 is in the initial position, the distance between the diameter-changing strip 9 and the straight arc plate 71 can be 3 mm, and the distance between the connecting strip 91 and the double-channel plate 72 can be 2 mm.

[0034] Refer to Figures 2-6 , there are multiple reaction modules, which are arranged in an equiangular array on the outer wall of the synthesis tube 7 with the center of the synthesis tube 7 as the center. A plurality of aggregate plates 701 are arranged at equal angles on the right outer wall of the synthesis tube 7. The right side of the aggregate plate 701 is the aggregate area 702, thus forming multiple micro-channel paths. The number of aggregate plates 701 is equal to the number of the equiangular array of reaction modules. That is, if the equiangular array of reaction modules is twelve, then the number and position of the aggregate plates 701 correspond one by one. At the same time, both the sealing strip 81 and the blocking strip 82 are in contact with the straight arc plate 71. At the same time, the widths of the straight arc plate 71, the double-channel plate 72, and the single-channel plate 73 are greater than the moving distances of the connecting strip 91 and the splicing strip 92, forming an effective sealing structure.

[0035] Among them, the aggregate plate 701 is located between the aggregate area 702 and the micro-channels on the surface of the synthesis tube 7. After the reaction solution flowing out of the multiple micro-channels passes through the aggregate plate 701, it will converge uniformly in the aggregate area 702, and the aggregate plate 701 is used to ensure that the reaction solution converges uniformly to the aggregate area 702.

[0036] Refer to Figures 2-6 , a plurality of closing blocks 11 are arranged outside the synthesis tube 7. Both the double-channel plate 72 and the barrier strip 8 are provided with short arc openings 12. The short arc strip 75 is located in the two short arc openings 12. Both the double-channel plate 72 and the single-channel plate 73 are provided with long arc openings 13. The long arc strip 74 is located in the two long arc openings 13. When the connecting strip 91 is in contact with the double-channel plate 72, the midline of the distance between the double-channel plate 72 and the barrier strip 8 coincides with the midline of the short arc strip 75.

[0037] In addition, each connection part is sealed with a polytetrafluoroethylene sealing ring, with a temperature tolerance range of 20 °C to 200 °C and good pressure resistance. At the same time, the material of the closing block 11 is also polytetrafluoroethylene.

[0038] Specifically, the long arc strip 74 and the short arc strip 75 are used to buffer and block the reaction solution, enhancing the mixing effect.

[0039] Referring to Figures 2-6 , for the assembly method of the material distribution part 5 and the circular sleeve 2, conventional screws can be used for fixation, which is convenient for disassembly and maintenance. The material distribution part 5 includes a material distribution ring 51 arranged inside the circular sleeve 2, and a material guiding disk 52 fixedly connected to the material distribution ring 51. The material guiding disk 52 is fixedly connected to the circular sleeve 2, and a plurality of material guiding ports 501 are equiangularly arranged on the material guiding disk 52.

[0040] Specifically, the material distribution ring 51 and the material guiding disk 52 are combined into an annular material distribution system, enabling the reaction solution to be evenly distributed in the circumferential direction, reducing the flow rate deviation. At the same time, the plurality of material guiding ports 501 can be in a gradually expanding shape, effectively reducing the local resistance when the reaction solution enters the microchannel, avoiding the generation of eddy currents and pressure losses due to sudden changes in flow velocity, and also helping the reaction solution to achieve preliminary mixing before entering the microchannel, improving the uniformity of the reaction solution distribution.

[0041] Referring to Figures 2-6 , the shaft disk 6 includes a rotating shaft 61 rotatably connected inside the circular sleeve 2, and a disk 62 fixedly connected to one end of the rotating shaft 61. The other end of the rotating shaft 61 extends outside the left support sleeve 1. A plurality of guiding grooves 621 are equiangularly arranged on the disk 62. The material guiding ports 501 communicate with the guiding grooves 621, and the guiding grooves 621 communicate with the microchannel and the two have the same number.

[0042] Specifically, by driving the rotating shaft 61 with a motor to make it rotate, the disk 62 drives the blocking strip 8 and the diameter-changing strip 9, realizing the change of the microchannel. At the same time, due to the docking of the guiding grooves 621 with the material guiding ports 501 and the microchannel, the reaction solution will enter the guiding grooves 621 from the material guiding ports 501 and finally enter the microchannel, avoiding the retention and leakage of the reaction solution at the connection, and ensuring that the reaction solution can efficiently and stably enter the microchannel for reaction.

[0043] Referring to Figures 1-9 , a feed inlet 31 and a discharge outlet 32 are respectively fixedly connected to the top and bottom of the sandwich shell 3. The feed inlet 31 communicates with the inside of the material distribution ring 51, and the discharge outlet 32 communicates with the collection area 702. An inner water inlet 21 and an outer water inlet 22 are fixedly connected to one side of the circular sleeve 2. A conduit 101 is fixedly connected to the inner sleeve 10. The conduit 101 passes through the arc-shaped opening 601 to avoid interference between the disk 62 and the conduit 101. The conduit 101 is connected to the inner water inlet 21, and the outer water inlet 22 is connected to the sandwich inside the sandwich shell 3. The inner water inlet 21 and the outer water inlet 22 are used to form an internal and external circulation to adjust the overall temperature balance of the reactor. The inner water inlet 21 will convey the water flow through the conduit 101 to between the inner sleeve 10 and the synthesis tube 7.

[0044] The working principle of the present invention is as follows: The reaction solution is transported to the feed port 31 at the top of the sandwich shell 3 through an external pipeline, and then enters the material distribution ring 51. It passes through multiple material guiding ports 501 on the material guiding plate 52 and enters the corresponding guiding grooves 621 on the disc 62. Subsequently, it enters between the straight arc plate 71 and the diameter-changing strip 9 from the guiding grooves 621, completing the preliminary distribution and introduction of the reaction solution. At the same time, the inner water inlet 21 transports the coolant to the space between the inner sleeve 10 and the synthesis tube 7 through the conduit 101 to control the temperature inside the microchannel reaction. The outer water inlet 22 transports the coolant to the sandwich inside the sandwich shell 3 to adjust the overall temperature balance of the entire reactor, ensuring that the reaction proceeds at an appropriate temperature and avoiding side reactions or reduced reaction efficiency caused by abnormal temperature. At this time, the barrier strip 8 is in the initial position, which fits with the double-channel plate 72 to block the channel between the double-channel plate 72 and the barrier strip 8. The reaction solution only passes through the channel between the double-channel plate 72 and the single-channel plate 73. The single-channel plate 73 is close to the straight arc plate 71, and at this time the flow path is relatively short, and the reaction solution passes through quickly. As the reaction progresses, the positions of the barrier strip 8 and the diameter-changing strip 9 can be adjusted before the reaction, or dynamically adjusted according to the situation of the reaction solution during the reaction. Using external drive, the shaft disc 6 rotates a certain angle, and the barrier strip 8 and the diameter-changing strip 9 rotate synchronously. The diameter-changing strip 9 approaches the straight arc plate 71, and the distance between the two decreases, increasing the resistance to the reaction solution, changing the cross-sectional area of the flow path, and thus controlling the fluid flow rate to make the reaction solution fully mixed in the microchannel. The connecting strip 91 and the splicing strip 92 fit with the double-channel plate 72 to block the passage between the double-channel plate 72 and the single-channel plate 73. At the same time, the barrier strip 8 is separated from the double-channel plate 72, and the reaction solution instead flows through the channel between the barrier strip 8 and the double-channel plate 72, extending the reaction path and the residence time. After the reaction solution that has completed the reaction flows out of each microchannel, it sequentially passes through the aggregate plate 701 on the outer wall of the right side of the synthesis tube 7 and converges to the aggregate area 702, and then is discharged through the discharge port 32 at the bottom of the sandwich shell 3.

[0045] Example two, referring to Figures 1-9 , which is the second embodiment of the present invention, provides a method for continuously synthesizing piperonylamine with a high yield. An intelligent flow reactor for continuously synthesizing piperonylamine with a high yield is used, including the following steps: Step 1: Dissolve piperonal in an organic solvent to form a homogeneous reaction solution.

[0046] Step 2: Transport it to the inside of the material distribution part 5 at a stable flow rate through a metering pump, and then enter the microchannels on the surface of the synthesis tube 7 to make the reaction solution fully contact and react.

[0047] Step 3: Adjust the reaction temperature inside the synthesis tube 7 through an external heating or cooling device.

[0048] Step 4: Drive the barrier strip 8 and the diameter-changing strip 9 according to requirements by using the shaft disc 6, thereby adjusting the channel length and size and changing the flow rate to affect the residence time of the reaction solution in the microchannel.

[0049] Step Five: Evaporate and remove the low-boiling organic solvents and unreacted raw materials first, and then obtain high-purity piperonylamine products through methods such as vacuum distillation.

[0050] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An intelligent flow reactor for the continuous synthesis of piperonylamine with high yield, comprising a left support sleeve (1), characterized in that: It further includes a circular sleeve (2) and a sandwich shell (3) fixedly connected to the left support sleeve (1), a right support sleeve (4) fixedly connected to one end of the sandwich shell (3), a material distributing member (5) fixedly connected to the circular sleeve (2), a shaft disc (6) rotatably connected inside the material distributing member (5), a synthesis tube (7) arranged inside the right support sleeve (4), a barrier strip (8) and a diameter-changing strip (9) both fixedly connected to the left end of the shaft disc (6), and an inner sleeve shell (10) located inside the synthesis tube (7) and fixedly connected to the right support sleeve (4). The inner sleeve shell (10) is fixedly connected to the inside of the right support sleeve (4). The right support sleeve (4) is in contact with the shaft disc (6). A plurality of the barrier strips (8) and diameter-changing strips (9) are arranged at equal angles. A plurality of the barrier strips (8) and diameter-changing strips (9) are both in contact with the outer wall of the synthesis tube (7) and have the same radian. A single barrier strip (8) and diameter-changing strip (9) form a microchannel with the synthesis tube (7). The shaft disc (6) changes the flow path of the microchannel through the barrier strips (8) and diameter-changing strips (9).

2. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 1, characterized in that: Reaction modules are arranged on the surface of the synthesis tube (7). The reaction modules include multiple groups of reaction modules connected end to end. Each reaction module includes a straight arc plate (71), a double-channel plate (72), a single-channel plate (73), a long arc strip (74), and a short arc strip (75). The straight arc plate (71) is located on the left side of the double-channel plate (72) and the single-channel plate (73). The long arc strip (74) is located between the single-channel plate (73) and the double-channel plate (72). The short arc strip (75) is located between the barrier strip (8) and the double-channel plate (72).

3. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 2, characterized in that: A seal strip (81) and a blocking strip (82) are fixedly connected to the barrier strip (8). When the barrier strip (8) is in contact with the double-channel plate (72), it is in the initial position.

4. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 3, characterized in that: A connecting strip (91) and a splicing strip (92) are fixedly connected to the diameter-changing strip (9). The connecting strip (91) is in contact with the left end of the single-channel plate (73). The splicing strip (92) is in contact with the right end of the single-channel plate (73). The distance between the diameter-changing strip (9) and the straight arc plate (71) is greater than the distance between the connecting strip (91) and the double-channel plate (72). The seal strip (81) is located on the left side of the connecting strip (91). The blocking strip (82) is located on the right side of the splicing strip (92).

5. The intelligent flow reactor for continuous synthesis of piperonylamine with high yield according to claim 4, characterized in that: There are multiple reaction modules, and they are arranged in an equiangular array distribution around the center of the synthesis tube (7) on the outer tube wall of the synthesis tube (7). A plurality of aggregate plates (701) are arranged at equal angles on the right outer wall of the synthesis tube (7). The right side of the aggregate plate (701) is an aggregate area (702). The number and positions of the seal strip (81), the blocking strip (82), the connecting strip (91), the splicing strip (92), and the single-channel plate (73) correspond one by one. Both the seal strip (81) and the blocking strip (82) are in contact with the straight arc plate (71).

6. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 4, wherein: A plurality of closed blocks (11) are arranged outside the synthesis tube (7). The double-channel plate (72) and the barrier strip (8) are both provided with short arc openings (12). The short arc strip (75) is located within the two short arc openings (12). The double-channel plate (72) and the single-channel plate (73) are both provided with long arc openings (13). The long arc strip (74) is located within the two long arc openings (13). When the connecting strip (91) is attached to the double-channel plate (72), the midline of the distance between the double-channel plate (72) and the barrier strip (8) coincides with the midline of the short arc strip (75).

7. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 1, characterized in that: The material distribution member (5) includes a material distribution ring (51) arranged inside the circular sleeve (2), and a material guiding disc (52) fixedly connected to the material distribution ring (51). The material guiding disc (52) is fixedly connected to the circular sleeve (2). A plurality of material guiding openings (501) are equiangularly arranged on the material guiding disc (52).

8. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 7, wherein: The shaft disc (6) includes a rotating shaft (61) rotatably connected inside the circular sleeve (2), and a disc (62) fixedly connected to one end of the rotating shaft (61). The other end of the rotating shaft (61) extends to the outside of the left support sleeve (1). A plurality of guiding grooves (621) are equiangularly arranged on the disc (62). The material guiding openings (501) communicate with the guiding grooves (621). The guiding grooves (621) communicate with the microchannels and the number of both is the same.

9. The intelligent flow reactor for the continuous synthesis of piperonylamine with high yield according to claim 8, characterized in that: The top and bottom of the sandwich shell (3) are respectively fixedly connected with a feed inlet (31) and a discharge outlet (32). The feed inlet (31) communicates with the inside of the material distribution ring (51). The discharge outlet (32) communicates with the aggregate area (702). One side of the circular sleeve (2) is fixedly connected with an inner water inlet (21) and an outer water inlet (22). A conduit (101) is fixedly connected to the inner sleeve (10). The conduit (101) penetrates through the arc-shaped opening (601). The conduit (101) is connected to the inner water inlet (21). The outer water inlet (22) is connected to the inside of the sandwich of the sandwich shell (3).

10. A continuous synthesis method for high yield of piperonylamine, using an intelligent flow reactor for continuous synthesis of piperonylamine with high yield as described in claim 1, characterized in that, Comprising the following steps: Step 1: Dissolve piperonal in an organic solvent to form a homogeneous reaction solution; Step 2: Transport it into the inside of the material distribution member (5) at a stable flow rate through a metering pump, and then into the microchannels on the surface of the synthesis tube (7) to enable the reaction solution to fully contact and react; Step 3: Adjust the reaction temperature inside the synthesis tube (7) through an external heating or cooling device; Step 4: Drive the barrier strip (8) and the diameter-changing strip (9) by using the shaft disc (6) according to requirements, so as to adjust the channel length and size, and change the flow rate to affect the residence time of the reaction solution in the microchannels; Step 5: First evaporate and remove the low-boiling organic solvent and unreacted raw materials, and then obtain a high-purity piperonylamine product through methods such as vacuum distillation.

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