A microchannel reactor and a method for preparing a Grignard reagent
By designing a micropipe reactor, the problems of poor mixing uniformity and difficult to remove reaction heat when synthesizing reagents in traditional kettle reactors are solved, and the effects of efficient mixing, rapid removal of reaction exothermic heat and better control of the reaction environment are achieved, and the selectivity, yield and quality stability of the product are improved.
Patent Information
- Application Number
- CN202510136666.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-07
- Publication Date
- 2025-04-04
AI Technical Summary
When synthesizing reagents in traditional kettle reactors, there are problems such as slow heat transfer, poor mixing uniformity, difficult product quality to control, and difficult reaction heat to remove.
A micropipe reactor is designed, including a feed module, a reaction module and a control module. There is a fluid passage between the reaction pipe and the reaction pipe in the reaction module, and the through holes are evenly distributed along the length of the reaction pipe to ensure that the solid and liquid materials are fully in contact and mixed. The control module is used to adjust the reaction parameters, including temperature, pressure and gas flow, to achieve rapid removal of reaction exothermic heat and better control of the reaction environment.
Through the micropipe reactor, the reaction materials can be efficiently mixed in a very small space, quickly remove reaction exothermic heat, improve reaction selectivity and yield, ensure the safety of the reaction process and the stability of product quality, and achieve a green, safe and continuous production process.
Smart Images
Figure CN119746754A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a micro-channel reactor and a method for preparing a Grignard reagent. Background Art
[0002] Grignard reagent is an extremely important reagent in the field of organic synthesis. It is used for Grignard reaction and is widely used in the fields of drug, fragrance, and polymer material synthesis. However, the synthesis conditions of Grignard reagent are relatively stringent, and usually need to be reacted in an oxygen-free, anhydrous environment. When using traditional kettle reactors to prepare Grignard reagents, high requirements are usually placed on the sealing of the equipment, because the sealing of the reactor directly affects the quality of the Grignard reagent, and the kettle reactor has defects such as slow heat and mass transfer and poor mixing uniformity. Therefore, the quality of the prepared Grignard reagent is difficult to control. At the same time, there is also the problem of difficulty in removing the reaction heat. Summary of the invention
[0003] The present invention provides a microchannel reactor and a method for preparing a Grignard reagent in order to solve the problems of slow heat and mass transfer, difficulty in fully mixing, difficulty in controlling product quality, and difficulty in removing reaction heat in the process of synthesizing Grignard reagents using conventional kettle reactors. The microchannel reactor provided by the present invention is conducive to full contact of the reaction materials, so that they can be efficiently mixed in a very small space, and can also quickly remove the reaction heat, so as to achieve better control of the reaction environment, effectively avoid the adverse situation of side reactions caused by excessively high local reaction temperatures, reduce the risk of energy accumulation, improve the selectivity, yield and quality stability of the product, and realize a green, safe and continuous production process.
[0004] The present invention adopts the following technical solutions to solve the above problems:
[0005] The present invention provides a micro-channel reactor, which comprises a feed module, a reaction module and a control module;
[0006] The feeding module includes a solid feeding mechanism and a liquid feeding mechanism;
[0007] The reaction module comprises a reaction pipeline; a reaction tube is arranged in the reaction pipeline, a fluid passage is provided between the outer wall of the reaction tube and the inner wall of the reaction tube, the extension direction of the reaction tube is the same as the length direction of the reaction tube, the reaction tube is a tubular structure with one end open and the other end closed, and a plurality of through holes communicating with the inner cavity of the reaction tube are arranged on the tube wall of the reaction tube;
[0008] The two ends of the reaction pipe are respectively provided with a first feed port and a second feed port; the end of the reaction pipe with an opening is arranged close to the first feed port, the first feed port is connected to the discharge port of the solid feeding mechanism, the solid feeding mechanism is used to transport solid materials into the reaction pipe, and the particle size of the solid materials is larger than the aperture of the through hole; the second feed port is connected to the discharge port of the liquid feeding mechanism, and the liquid feeding mechanism is used to transport liquid materials into the reaction pipe;
[0009] The control module is used to control the reaction parameters in the reaction pipeline.
[0010] In the present invention, preferably, the through holes are evenly distributed along the length direction of the reaction tube.
[0011] In the present invention, the number of the second feed ports is preferably 1 to 5, and they can be respectively connected to the discharge ports of the liquid feed mechanism to respectively transport different types of liquid materials.
[0012] In some preferred embodiments, the number of the reaction tubes is multiple, preferably 2 to 5, and more preferably 2 to 3.
[0013] In some preferred embodiments, the inner diameter of the reaction tube is 1 to 6 cm, preferably 1 to 3 cm.
[0014] In some preferred embodiments, the ratio of the length of the reaction tube to the inner diameter of the reaction pipe is (2-15):1, preferably (2-10):1.
[0015] In some preferred embodiments, the inner diameter of the reaction pipe is 2 to 10 cm, preferably 2 to 6 cm.
[0016] In some preferred embodiments, the ratio of the length of the reaction pipe to the inner diameter of the reaction pipe is (2-15):1, preferably (2-10):1.
[0017] In some more preferred embodiments, the length of the reaction tube is substantially the same as the length of the reaction pipe.
[0018] In the present invention, the arrangement of the reaction pipe can make the solid material evenly distributed along the length direction of the reaction pipe, and is conducive to the full contact between the solid material and the liquid material, so that the reaction materials can be efficiently mixed in a very small space; in addition, since the reaction pipe of the present invention has a large specific surface area, it can also quickly remove the reaction heat, which can achieve better control of the reaction environment, improve the selectivity and yield of the reaction, and ensure the safety of the reaction process.
[0019] In some preferred embodiments, the reaction pipe is provided with a sight glass for observing the reaction conditions and material flow rate inside the reaction pipe.
[0020] In some preferred embodiments, a temperature control unit is provided on the outer wall of the reaction pipe, and the temperature control unit is signal-connected to the control module.
[0021] In some more preferred embodiments, the reaction pipe includes a plurality of reaction areas, and a temperature control unit is provided on the outer wall of the reaction pipe corresponding to each reaction area; the number of the reaction areas is preferably 2 to 4, and more preferably 3 to 4.
[0022] In the present invention, the temperature control unit is preferably an automatic temperature control unit; the temperature control unit is preferably an electric heating unit or a fluid heating unit.
[0023] In the present invention, by respectively providing a temperature control unit on the outer wall of the reaction pipe corresponding to each reaction area, the temperature of each reaction area in the reaction pipe can be independently and accurately controlled, effectively avoiding adverse side reactions caused by excessively high local reaction temperatures, and improving the stability of product quality.
[0024] In some preferred embodiments, the control module includes a temperature probe, a pressure probe, an exhaust port, and an air inlet; the temperature probe and the pressure probe are respectively used to detect the temperature and pressure in the reaction pipe, the exhaust port is used to extract the air in the reaction pipe, and the air inlet is used to pass an inert gas into the reaction pipe; preferably, the control module is also provided with a safety valve port.
[0025] In the present invention, the air extraction port of the control module preferably includes a vacuum valve, and the air inlet of the control module preferably includes an inert gas valve, such as a nitrogen valve.
[0026] In some preferred embodiments, the control module further comprises a product outlet, which is connected to the opening of the reaction tube and is used to output the product from the micro-channel reactor.
[0027] In some preferred embodiments, the control module is disposed between the solid feeding mechanism and the reaction pipe, and a passage connecting the solid feeding mechanism and the reaction pipe is disposed inside the control module.
[0028] In some preferred embodiments, the solid feeding mechanism includes a storage bin and a first valve, and the first valve is disposed between the storage bin and the reaction pipeline.
[0029] In some preferred embodiments, the liquid feeding mechanism is connected to an external liquid storage tank via a liquid feeding pipeline.
[0030] In some more preferred embodiments, the solid feeding mechanism also includes a feeder, which is arranged between the storage bin and the first valve and is used to transport solid materials. The feeder is preferably a star-shaped feeder. Preferably, the solid feeding mechanism also includes a second valve, which is arranged between the storage bin and the feeder.
[0031] In the present invention, the first valve and the second valve are preferably classified as pneumatic valves or electric valves according to the driving mode, and are more preferably pneumatic valves; the first valve and the second valve are preferably classified as ball valves, gate valves or butterfly valves according to the structural form, and are more preferably globe valves.
[0032] In the present invention, the feeder can be used to measure the amount of solid material, and is also helpful for conveying the solid material to the downstream reaction module.
[0033] In some preferred embodiments, a feed port, an exhaust port and an air inlet are provided on the upper portion of the storage bin; the feed port is used to allow solid materials to be input into the storage bin, the exhaust port is used to extract the air in the storage bin, and the air inlet is used to pass inert gas into the storage bin.
[0034] In the present invention, the air extraction port of the storage bin preferably includes a vacuum valve, and the air inlet of the storage bin preferably includes an inert gas valve, such as a nitrogen valve.
[0035] In some preferred embodiments, a stirring unit is provided inside the storage bin, preferably a screw-belt stirring unit.
[0036] In some preferred embodiments, the storage bin is further provided with an online oxygen content tester for detecting the oxygen content in the solid feeding mechanism.
[0037] In some preferred embodiments, the storage bin is made of stainless steel or enamel.
[0038] In some preferred embodiments, an air suction port and an air inlet are provided on the upper portion of the liquid storage tank; the air suction port is used to extract the air in the liquid storage tank, and the air inlet is used to pass an inert gas into the liquid storage tank.
[0039] In the present invention, the air extraction port of the liquid storage tank preferably includes a vacuum valve, and the air inlet of the liquid storage tank preferably includes an inert gas valve, such as a nitrogen valve.
[0040] In some preferred embodiments, the liquid storage tank is further provided with an online oxygen content tester for detecting the oxygen content in the liquid feeding mechanism.
[0041] In the present invention, the liquid storage tank preferably adopts a double-end mechanical seal to ensure good air tightness inside the liquid storage tank.
[0042] The present invention provides a method for preparing a Grignard reagent, which is carried out using the micro-channel reactor as described above;
[0043] The preparation method of the Grignard reagent is carried out by the following steps:
[0044] S1, putting solid materials into the reaction pipe, and passing liquid materials into the reaction pipe;
[0045] S2, adjusting the parameters of the reaction environment in the reaction pipeline so that the solid material and the liquid material react under preset conditions to obtain a Grignard reagent;
[0046] S3, outputting the obtained Format reagent from the reaction pipeline.
[0047] In some preferred embodiments, before step S1, the air in the reaction pipe is replaced with an inert gas.
[0048] In some preferred embodiments, in step S1, before the solid material is put into the reaction tube, the solid material is kept in an inert gas environment.
[0049] In some preferred embodiments, in step S1, the solid material is premixed before being put into the reaction tube.
[0050] In some preferred embodiments, in step S1, before the liquid material is fed into the reaction pipe, oxygen in the liquid material is removed so that the liquid material meets the reaction requirements.
[0051] In some preferred embodiments, in step S1, the liquid material is premixed before being fed into the reaction pipe.
[0052] In the present invention, the inert gas environment preferably has an oxygen content of ≤1000ppm.
[0053] In some preferred embodiments, in step S1, the solid material is firstly put into the reaction pipe, and then the liquid material is introduced into the reaction pipe.
[0054] In some preferred embodiments, in step S1, the solid material includes magnesium and an initiator; the particle size of the magnesium is preferably 100-1000 μm, more preferably 500-800 μm; and the initiator preferably includes iodine, methyl iodide or ethyl iodide.
[0055] In some preferred embodiments, in step S1, the liquid materials are anhydrous solvent and halogenated hydrocarbon; the anhydrous solvent is preferably anhydrous ether or anhydrous tetrahydrofuran; the halogenated hydrocarbon is preferably methyl halide, ethyl halide or phenyl halide, for example: methyl chloride, ethyl bromide, bromobenzene or chlorobenzene.
[0056] In some preferred embodiments, in step S2, the temperature in the reaction pipe is 20-80°C.
[0057] In the present invention, the reaction temperature of the Grignard reagent varies depending on the specific halogenated hydrocarbon and initiator. When the initiator is iodine, the temperature in the reaction conduit is preferably 60-80°C; when the initiator is methyl iodide, the temperature in the reaction conduit is preferably room temperature; when the initiator is ethyl iodide, the temperature in the reaction conduit is preferably 35-45°C.
[0058] In some preferred embodiments, in step S2, the reaction pipe includes a plurality of reaction zones, and the temperature of the reaction zone near the second feed port is set to be greater than the temperature of the reaction zone near the first feed port.
[0059] In some preferred embodiments, the solid materials are magnesium and iodine, and the liquid materials are anhydrous solvent and halogenated hydrocarbons; the molar ratio of the magnesium to the halogenated hydrocarbon is (3-1):1, more preferably (1.5-1:1); the ratio of the volume (L) of the anhydrous solvent to the mass (Kg) of the halogenated hydrocarbon is preferably (1-5):1, more preferably (1-2:1); the feed rate of the liquid material is 1-5 L / min.
[0060] In some preferred embodiments, the reaction pipe is provided with at least one first reaction zone and one second reaction zone in sequence from the second feed port to the first feed port, the temperature of the first reaction zone is set to 60-80°C, and the temperature of the second reaction zone is set to 30-45°C.
[0061] In some more preferred embodiments, the air in the solid feeding mechanism and the reaction pipe is first replaced with an inert gas, and while controlling the reaction pipe to maintain an inert gas environment, solid material is fed into the solid feeding mechanism, and replaced again with an inert gas, and then the solid material is transported to the reaction pipe; the air in the liquid feeding mechanism is then replaced with an inert gas, and then liquid material is input into the liquid feeding mechanism, and replaced again with an inert gas; the reaction pipe is heated to a preset temperature; and then the liquid material is passed into the reaction pipe for reaction to obtain a Grignard reagent, and finally the obtained Grignard reagent is output from the reaction pipe.
[0062] In a further preferred embodiment, the first valve, the second valve and the switch valve of the feeder are first opened, and the solid feeding mechanism and the reaction pipeline are evacuated to a vacuum (-0.1 MPa), and then the vacuum valve of the storage bin is closed, and the nitrogen valve of the storage bin is opened for equalization and then closed, and the above vacuuming and nitrogen replacement are repeated 2 to 3 times to reduce the oxygen content to ≤1000ppm; then the first valve, the second valve and the switch valve of the feeder are closed, and magnesium and iodine are added from the feed port of the storage bin. After the feeding is completed, the nitrogen is replaced 2 to 3 times, and then the solid materials are stirred until they are evenly mixed, and the first valve is opened. The first valve, the second valve and the switch valve of the feeder are used to transport the solid material to the reaction pipe; the air in the liquid feeding mechanism is replaced with nitrogen by the same vacuum and nitrogen replacement operations as above, and the oxygen content is reduced to ≤1000ppm; then anhydrous solvent and halogenated hydrocarbon are input into the liquid feeding mechanism, and nitrogen is replaced 2 to 3 times after the feeding is completed, and then the liquid materials are stirred until they are evenly mixed; the reaction pipe is heated to a preset temperature; then the liquid material is introduced into the reaction pipe for reaction, and finally the Grignard reagent is output from the reaction pipe, and the product is collected in a dry, nitrogen-sealed device for subsequent Grignard reaction.
[0063] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.
[0064] The reagents and raw materials used in the present invention are commercially available.
[0065] The positive and progressive effects of the present invention are:
[0066] (1) The microchannel reactor provided by the present invention is conducive to the full contact of the reaction materials, so that they can be efficiently mixed in a very small space, and can also quickly remove the reaction exotherm, thereby achieving better control of the reaction environment, improving the selectivity and yield of the reaction, ensuring the safety of the reaction process, and at the same time accelerating the reaction rate, greatly reducing energy consumption.
[0067] (2) The microchannel reactor provided by the present invention can accurately control the reaction temperature of the reaction channel, improve the heating uniformity, effectively avoid the adverse situation of side reactions caused by excessive local reaction temperature, reduce the risk of energy accumulation, improve the stability of product quality, and realize a green, safe and continuous production process. BRIEF DESCRIPTION OF THE DRAWINGS
[0068] Figure 1 This is a schematic diagram of the structure of the micro-channel reactor of Example 1 of the present invention.
[0069] Figure 2 Schematic diagram of the connection between the microchannel reactor and the external liquid storage tank in Example 1 of the present invention.
[0070] Figure 3 This is a schematic diagram of the structure of the reaction tube of the micro-channel reactor of Example 1 of the present invention.
[0071] Figure 4 Schematic diagram of the structure of the control module (cross section) of the micro-channel reactor of Example 1 of the present invention.
[0072] Figure 5 Schematic diagram of the structure of the product discharge port (cross section) of the micro-channel reactor of Example 1 of the present invention.
[0073] Description of reference numerals:
[0074] Storage silo 1
[0075] Star feeder 2
[0076] First pneumatic ball valve 3
[0077] Second pneumatic ball valve 4
[0078] Control module 5
[0079] Temperature probe 51
[0080] Pressure probe 52
[0081] Vacuum valve 53
[0082] Nitrogen valve 54
[0083] Safety valve port 55
[0084] Reaction pipeline 6
[0085] First reaction area 61
[0086] Second reaction zone 62
[0087] Circular import 63
[0088] Loop Exit 64
[0089] Reaction pipe 7
[0090] Through hole 71
[0091] First feed port 8
[0092] Second feed port 9
[0093] Mirror 10
[0094] Product outlet 11
[0095] Liquid feed line 12
[0096] Liquid storage tank 13
[0097] Working fixed platform 14. DETAILED DESCRIPTION
[0098] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.
[0099] Example 1
[0100] This embodiment provides a micro-channel reactor, such as Figures 1 to 5 As shown, the micro-channel reactor includes a feed module, a reaction module and a control module 5;
[0101] The feeding module includes a solid feeding mechanism and a liquid feeding mechanism;
[0102] The reaction module includes a reaction pipe 6; a reaction pipe 7 is arranged in the reaction pipe 6, a fluid passage is provided between the outer wall of the reaction pipe 7 and the inner wall of the reaction pipe 6, the extension direction of the reaction pipe 7 is the same as the length direction of the reaction pipe 6, the reaction pipe 7 is a tubular structure with one end open and the other end closed, and a plurality of through holes 71 communicating with the inner cavity of the reaction pipe 7 are arranged on the pipe wall of the reaction pipe 7;
[0103] A first feed port 8 and a second feed port 9 are respectively provided at both ends of the reaction pipe 6; an open end of the reaction pipe 7 is arranged close to the first feed port 8, and the first feed port 8 is connected to the discharge port of a solid feed mechanism, and the solid feed mechanism is used to transport solid materials into the reaction pipe 7, and the particle size of the solid materials is larger than the aperture of the through hole 71; the second feed port 9 is connected to the discharge port of a liquid feed mechanism, and the liquid feed mechanism is used to transport liquid materials into the reaction pipe 6;
[0104] The control module 5 is used to control the reaction parameters in the reaction pipe 6 .
[0105] In this embodiment, the through holes 71 are evenly distributed along the length direction of the reaction tube 7 .
[0106] In this embodiment, different types of liquid materials are mixed evenly in the liquid storage tank 13 and then enter the reaction pipe 6 from a second feed inlet 9 .
[0107] In other embodiments, different types of liquid materials may not be premixed, but may enter the reaction pipe 6 from different second feed ports 9 through different flow paths. Figure 5 shown.
[0108] In this embodiment, the number of reaction tubes 7 is two.
[0109] In this embodiment, the inner diameter of the reaction tube 7 is 1.5 cm.
[0110] In this embodiment, the length of the reaction tube 7 is 45 cm.
[0111] In this embodiment, the inner diameter of the reaction pipe 6 is 5 cm.
[0112] In this embodiment, the length of the reaction pipe 6 is 45 cm.
[0113] In this embodiment, a viewing mirror 10 is provided on the reaction pipe 6 for observing the reaction conditions and material flow rate inside the reaction pipe 6 .
[0114] In this embodiment, a temperature control unit is provided on the outer wall of the reaction pipe 6 , and the temperature control unit is signal-connected to the control module 5 .
[0115] In this embodiment, the reaction pipe 6 includes a plurality of reaction areas, and a temperature control unit is provided on the outer wall of the reaction pipe 6 corresponding to each reaction area; the number of the reaction areas is 3.
[0116] In this embodiment, the temperature control unit is an automatic temperature control unit; the temperature control unit is a fluid heating unit; and a circulation inlet 63 and a circulation outlet 64 are respectively provided on the outer wall of the reaction pipe 6 corresponding to each reaction area.
[0117] In this embodiment, the control module 5 includes a temperature probe 51, a pressure probe 52, an exhaust port, and an air inlet; the temperature probe and the pressure probe are used to detect the temperature and pressure in the reaction pipe 6 respectively, the exhaust port is used to extract the air in the reaction pipe 6, and the air inlet is used to pass inert gas into the reaction pipe 6; the control module 5 is also provided with a safety valve port 55.
[0118] In this embodiment, the air extraction port of the control module 5 includes a vacuum valve 53 , and the air inlet of the control module 5 includes a nitrogen valve 54 .
[0119] In this embodiment, the control module 5 further includes a product discharge port 11, which is in communication with the opening of the reaction tube 7, and is used to discharge the product from the micro-channel reactor.
[0120] In this embodiment, the control module 5 is disposed between the solid feeding mechanism and the reaction pipe 6 , and a passage connecting the solid feeding mechanism and the reaction pipe 7 is disposed inside the control module 5 .
[0121] In this embodiment, the solid feeding mechanism includes a storage bin 1 and a first valve, and the first valve is disposed between the storage bin 1 and the reaction pipeline 6 .
[0122] In this embodiment, the liquid feeding mechanism is connected to an external liquid storage tank 13 via a liquid feeding pipeline 12 .
[0123] In this embodiment, the solid feeding mechanism also includes a feeder, which is arranged between the storage bin 1 and the first valve and is used to transport solid materials. The feeder is a star-shaped feeder 2; the solid feeding mechanism also includes a second valve, which is arranged between the storage bin 1 and the feeder.
[0124] In this embodiment, the first valve and the second valve are respectively a first pneumatic ball valve 3 and a second pneumatic ball valve 4 .
[0125] In this embodiment, the feeder can be used to measure the amount of solid material, and is also helpful in transporting the solid material to the downstream reaction module.
[0126] In this embodiment, a feed port, an air extraction port and an air inlet are provided on the upper portion of the storage bin 1; the feed port is used to allow solid materials to be input into the storage bin 1, the air extraction port is used to extract the air in the storage bin 1, and the air inlet is used to pass inert gas into the storage bin 1.
[0127] In this embodiment, the air extraction port of the storage bin 1 includes a vacuum valve, and the air inlet of the storage bin 1 includes a nitrogen valve.
[0128] In this embodiment, a ribbon stirring unit is provided inside the storage bin 1 .
[0129] In this embodiment, the storage bin 1 is also provided with an online oxygen content tester for detecting the oxygen content in the solid feeding mechanism.
[0130] In this embodiment, the material of the storage bin 1 is stainless steel.
[0131] In this embodiment, an air suction port and an air inlet are provided at the upper portion of the liquid storage tank 13 ; the air suction port is used to extract the air in the liquid storage tank 13 , and the air inlet is used to pass the inert gas into the liquid storage tank 13 .
[0132] In this embodiment, the air extraction port of the liquid storage tank 13 includes a vacuum valve, and the air inlet of the liquid storage tank 13 includes a nitrogen valve.
[0133] In this embodiment, the liquid storage tank 13 is also provided with an online oxygen content tester for detecting the oxygen content in the liquid feeding mechanism.
[0134] In this embodiment, the liquid storage tank 13 adopts a double-end mechanical seal to ensure good air tightness inside the liquid storage tank 13.
[0135] Example 2
[0136] This embodiment discloses a method for preparing a Grignard reagent, which is carried out using the microchannel reactor described in Example 1. The number of reaction areas in this embodiment is 3, and the specific steps are as follows:
[0137] Open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, close the second feed port 9, evacuate the solid feeding mechanism and the reaction pipeline 6 to a vacuum (-0.1MPa) through the vacuum port of the storage bin 1, close the vacuum valve of the storage bin 1, open the nitrogen valve of the storage bin 1 to equalize the pressure, and close it after the pressure reaches 0.02MPa. Repeat the above vacuuming and nitrogen replacement twice. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 340ppm.
[0138] Then, close the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, add 10 kg of magnesium particles and 20 g of iodine from the feed port of the storage bin 1, and replace with nitrogen twice after the feeding is completed. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 280 ppm. Then stir until the solid materials are evenly mixed, open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, and transport the solid materials to the reaction tube 7 so that the materials are evenly filled in the reaction tube 7.
[0139] Open the bottom valve of the liquid storage tank 13, evacuate the liquid feeding mechanism, liquid feeding pipeline 12, and liquid storage tank 13 to -0.1MPa through the suction port of the liquid storage tank 13, close the vacuum valve of the liquid storage tank 13, open the nitrogen valve of the liquid storage tank 13 to equalize the pressure, and close it after the pressure reaches 0.02MPa. Repeat the above vacuuming and nitrogen replacement twice. The online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 560ppm. Close the bottom valve of the liquid storage tank 13, use a pump to pump 46.3kg of chlorobenzene and 63.2L of anhydrous tetrahydrofuran into the liquid storage tank 13. After the feeding is completed, the nitrogen is replaced twice. The online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 320ppm.
[0140] After the nitrogen replacement is completed, all valves of the liquid storage tank 13 are closed, and the temperature control unit of the microchannel reactor is opened, including two first reaction areas 61 and one second reaction area 62. The temperature of the first reaction area 61 is set to 65°C, and the temperature of the second reaction area 62 is set to 30°C. After the temperature stabilizes, the bottom valve of the liquid storage tank 13 and the second feed port 9 are opened, and the liquid material is pumped into the reaction pipe 6 at a flow rate of 1L / min. After sufficient reaction with the solid material, the obtained Grignard reagent is output from the product discharge port 11, and the product is collected in a dry, nitrogen-sealed device for subsequent Grignard reaction.
[0141] The conversion rate of the Grignard reagent prepared in this example is 98.5%.
[0142] Example 3
[0143] This embodiment discloses a method for preparing a Grignard reagent, which is carried out using the microchannel reactor described in Example 1. The number of reaction areas in this embodiment is 4, and the specific steps are as follows:
[0144] Open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, close the second feed port 9, evacuate the solid feeding mechanism and the reaction pipeline 6 to a vacuum (-0.1MPa) through the vacuum port of the storage bin 1, close the vacuum valve of the storage bin 1, open the nitrogen valve of the storage bin 1 to equalize the pressure, and close it after the pressure reaches 0.02MPa. Repeat the above vacuuming and nitrogen replacement twice. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 340ppm.
[0145] Then, close the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, add 22 kg of magnesium particles and 20 g of iodine from the feed port of the storage bin 1, and replace with nitrogen twice after the feeding is completed. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 280 ppm. Then stir until the solid material is evenly mixed, open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, and transport the solid material to the reaction tube 7 so that the material is evenly filled in the reaction tube 7.
[0146] Open the bottom valve of the liquid storage tank 13, evacuate the liquid feeding mechanism, liquid feeding pipeline 12, and liquid storage tank 13 to -0.1MPa through the suction port of the liquid storage tank 13, close the vacuum valve of the liquid storage tank 13, open the nitrogen valve of the liquid storage tank 13 to level the pressure, and close it after the pressure reaches 0.02MPa, repeat the above vacuuming and nitrogen replacement twice, and the online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 560ppm. Close the bottom valve of the liquid storage tank 13, use a pump to pump 129.3kg bromobenzene and 130.1L anhydrous tetrahydrofuran into the liquid storage tank 13, and after the feeding is completed, the nitrogen is replaced twice, and the online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 210ppm.
[0147] After the nitrogen replacement is completed, all valves of the liquid storage tank 13 are closed, and the temperature control unit of the microchannel reactor is opened, including three first reaction areas 61 and one second reaction area 62. The temperature of the first reaction area 61 is set to 70°C, and the temperature of the second reaction area 62 is set to 45°C. After the temperature stabilizes, the bottom valve and the second feed port 9 of the liquid storage tank 13 are opened, and the liquid material is pumped into the reaction pipe 6 at a flow rate of 2.5L / min. After sufficient reaction with the solid material, the obtained Grignard reagent is output from the product discharge port 11, and the product is collected in a dry, nitrogen-sealed device for subsequent Grignard reaction.
[0148] The conversion rate of the Grignard reagent prepared in this example is 98.7%.
[0149] Example 4
[0150] This embodiment discloses a method for preparing a Grignard reagent, which is carried out using the microchannel reactor described in Example 1. The number of reaction areas in this embodiment is 4, and the specific steps are as follows:
[0151] Open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, close the second feed port 9, evacuate the solid feeding mechanism and the reaction pipeline 6 to a vacuum (-0.1MPa) through the vacuum port of the storage bin 1, close the vacuum valve of the storage bin 1, open the nitrogen valve of the storage bin 1 to equalize the pressure, and close it after the pressure reaches 0.02MPa. Repeat the above vacuuming and nitrogen replacement twice. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 340ppm.
[0152] Then, close the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, add 45 kg of magnesium particles and 25 g of iodine from the feed port of the storage bin 1, and replace with nitrogen twice after the feeding is completed. The online oxygen content tester of the storage bin 1 shows that the oxygen content is 280 ppm. Then stir until the solid material is evenly mixed, open the first pneumatic ball valve 3, the second pneumatic ball valve 4 and the switch valve of the star feeder 2, and transport the solid material to the reaction tube 7 so that the material is evenly filled in the reaction tube 7.
[0153] Open the bottom valve of the liquid storage tank 13, evacuate the liquid feeding mechanism, liquid feeding pipeline 12, and liquid storage tank 13 to -0.1MPa through the suction port of the liquid storage tank 13, close the vacuum valve of the liquid storage tank 13, open the nitrogen valve of the liquid storage tank 13 to level the pressure, and close it after the pressure reaches 0.02MPa, repeat the above vacuuming and nitrogen replacement twice, and the online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 560ppm. Close the bottom valve of the liquid storage tank 13, use a pump to pump 134.5kg bromobenzene and 230.4L anhydrous ether into the liquid storage tank 13, and after the feeding is completed, the nitrogen is replaced twice, and the online oxygen content tester of the liquid storage tank 13 shows that the oxygen content is 420ppm.
[0154] After the nitrogen replacement is completed, all valves of the liquid storage tank 13 are closed, and the temperature control unit of the microchannel reactor is opened, including three first reaction areas 61 and one second reaction area 62. The temperature of the first reaction area 61 is set to 60°C, and the temperature of the second reaction area 62 is set to 30°C. After the temperature stabilizes, the bottom valve of the liquid storage tank 13 and the second feed port 9 are opened, and the liquid material is pumped into the reaction pipe 6 at a flow rate of 3.5L / min. After sufficient reaction with the solid material, the obtained Grignard reagent is output from the product discharge port 11, and the product is collected in a dry, nitrogen-sealed device for subsequent Grignard reaction.
[0155] The conversion rate of the Grignard reagent prepared in this example is 99.2%.
Claims
1. A microchannel reactor, characterized in that: The micro-channel reactor comprises a feed module, a reaction module and a control module; The feeding module includes a solid feeding mechanism and a liquid feeding mechanism; The reaction module comprises a reaction pipeline; a reaction tube is arranged in the reaction pipeline, a fluid passage is provided between the outer wall of the reaction tube and the inner wall of the reaction tube, the extension direction of the reaction tube is the same as the length direction of the reaction tube, the reaction tube is a tubular structure with one end open and the other end closed, and a plurality of through holes communicating with the inner cavity of the reaction tube are arranged on the tube wall of the reaction tube; The two ends of the reaction pipe are respectively provided with a first feed port and a second feed port; the end of the reaction pipe with an opening is arranged close to the first feed port, the first feed port is connected to the discharge port of the solid feeding mechanism, the solid feeding mechanism is used to transport solid materials into the reaction pipe, and the particle size of the solid materials is larger than the aperture of the through hole; the second feed port is connected to the discharge port of the liquid feeding mechanism, and the liquid feeding mechanism is used to transport liquid materials into the reaction pipe; The control module is used to control the reaction parameters in the reaction pipeline.
2. The microchannel reactor according to claim 1, characterized in that: The number of the reaction tubes is multiple, preferably 2 to 5; And / or, the inner diameter of the reaction tube is 1 to 6 cm, preferably 1 to 3 cm; And / or, the ratio of the length of the reaction tube to the inner diameter of the reaction pipe is (2-15):1, preferably (2-10):1; And / or, the inner diameter of the reaction pipe is 2 to 10 cm, preferably 2 to 6 cm; And / or, the ratio of the length of the reaction pipe to the inner diameter of the reaction pipe is (2-15):1, preferably (2-10):1; And / or, the reaction pipeline is provided with a sight glass for observing the reaction conditions and material flow rate inside the reaction pipeline.
3. The microchannel reactor according to claim 1, characterized in that: A temperature control unit is provided on the outer wall of the reaction pipe, and the temperature control unit is connected to the control module by signal.
4. The microchannel reactor according to claim 3, characterized in that: The reaction pipe comprises a plurality of reaction areas, and a temperature control unit is respectively arranged on the outer wall of the reaction pipe corresponding to each reaction area; the number of the reaction areas is preferably 2 to 4.
5. The microchannel reactor according to claim 1, characterized in that: The control module includes a temperature probe, a pressure probe, an air extraction port, and an air inlet; the temperature probe and the pressure probe are used to detect the temperature and pressure in the reaction pipeline, respectively, the air extraction port is used to extract the air in the reaction pipeline, and the air inlet is used to pass inert gas into the reaction pipeline; preferably, the control module is also provided with a safety valve port; And / or, the control module further comprises a product outlet, the product outlet being in communication with the opening of the reaction tube, for allowing the product to be output from the micro-channel reactor; And / or, the control module is arranged between the solid feeding mechanism and the reaction pipe, and a channel connecting the solid feeding mechanism and the reaction pipe is arranged inside the control module.
6. The microchannel reactor according to claim 1, characterized in that: The solid feeding mechanism comprises a storage bin and a first valve, wherein the first valve is arranged between the storage bin and the reaction pipeline; And / or, the liquid feeding mechanism is connected to an external liquid storage tank via a liquid feeding pipeline.
7. The microchannel reactor according to claim 6, characterized in that: The solid feeding mechanism further comprises a feeder, which is disposed between the storage bin and the first valve and is used to convey solid materials. The feeder is preferably a star-shaped feeder. Preferably, the solid feeding mechanism further comprises a second valve, which is disposed between the storage bin and the feeder. And / or, a feed port, an air extraction port and an air inlet are provided on the upper portion of the storage bin; the feed port is used to allow solid materials to be input into the storage bin, the air extraction port is used to extract air from the storage bin, and the air inlet is used to pass inert gas into the storage bin; And / or, a stirring unit is provided inside the storage bin, preferably a spiral ribbon stirring unit; And / or, the storage bin is further provided with an online oxygen content tester for detecting the oxygen content in the solid feeding mechanism; And / or, the material of the storage bin is stainless steel or enamel.
8. A method for preparing a Grignard reagent, characterized in that: It is carried out using a micro-channel reactor as described in any one of claims 1 to 7; The preparation method of the Grignard reagent is carried out by the following steps: S1, putting solid materials into the reaction pipe, and passing liquid materials into the reaction pipe; S2, adjusting the parameters of the reaction environment in the reaction pipeline so that the solid material and the liquid material react under preset conditions to obtain a Grignard reagent; S3, outputting the obtained Format reagent from the reaction pipeline.
9. The method for preparing the Grignard reagent according to claim 8, characterized in that: Before step S1, the air in the reaction pipe is replaced with an inert gas; and / or, in step S1, before the solid material is put into the reaction tube, the solid material is kept in an inert gas environment; And / or, in step S1, before the solid material is put into the reaction tube, the solid material is pre-mixed; And / or, in step S1, before the liquid material is put into the reaction pipe, oxygen in the liquid material is removed so that the liquid material meets the reaction requirements; And / or, in step S1, the liquid material is premixed before being fed into the reaction pipe; And / or, in step S1, firstly, solid material is put into the reaction pipe, and then liquid material is passed into the reaction pipe; And / or, in step S1, the solid material comprises magnesium and an initiator; the particle size of the magnesium is preferably 100-1000 μm, more preferably 500-800 μm; the initiator preferably comprises iodine, methyl iodide or ethyl iodide; And / or, in step S1, the liquid material is an anhydrous solvent and a halogenated hydrocarbon; the anhydrous solvent is preferably anhydrous ether or anhydrous tetrahydrofuran; the halogenated hydrocarbon is preferably a methyl halide, an ethyl halide or a phenyl halide, for example, methyl chloride, ethyl bromide, bromobenzene or chlorobenzene; and / or, in step S2, the temperature in the reaction pipe is 20 to 80° C.; And / or, in step S2, the reaction pipe includes a plurality of reaction zones, and the temperature of the reaction zone near the second feed port is set to be greater than the temperature of the reaction zone near the first feed port.
10. The method for preparing the Grignard reagent according to claim 9, characterized in that: The solid materials are magnesium and iodine, and the liquid materials are anhydrous solvent and halogenated hydrocarbons; the molar ratio of the magnesium to the halogenated hydrocarbon is (3-1):1, more preferably (1.5-1):1; the ratio of the volume of the anhydrous solvent to the mass of the halogenated hydrocarbon is preferably (1-5):1, more preferably (1-2):1; the feed rate of the liquid material is 1-5 L / min; The reaction pipeline is provided with at least one first reaction zone and one second reaction zone in sequence from the second feed port to the first feed port. The temperature of the first reaction zone is set to 60-80°C, and the temperature of the second reaction zone is set to 30-45°C.