Novel continuous efficient reaction device and operation method thereof

Abstract

The invention discloses a novel continuous efficient reaction device and an operation method thereof, and relates to the technical field of reaction devices.The novel continuous efficient reaction device comprises a first heat exchanger, a first pump, a second pump, corresponding connecting pipelines, a material inlet and a material outlet, an outlet of the first pump is connected to an inlet of the second pump through a pipeline, and an outlet of the second pump is connected to an inlet of the first heat exchanger; an outlet of the first heat exchanger is connected to a first feeding port of the first pump, the first feeding port is formed in the front end of an inlet of the first pump, a feeding port of the second pump serves as a second feeding port, and a discharging port is formed in a pipeline of the first heat exchanger. Efficient heat exchange is achieved through large-flow forced circulation and forced stirring, materials circularly flow under the action of the first large-flow pump, heat generated by reaction is taken away through a large number of products, heat exchange cooling is further conducted in the heat exchanger, and part of products of the cooled materials are discharged out of a reaction system.

Description

Technical Field

[0001] The present invention relates to the technical field of reaction devices, and particularly relates to a novel continuous and efficient reaction device and an operation method thereof. Background Art

[0002] With the increasing requirements of the chemical industry for process safety design and control, the requirements for enhancing the inherent safety of hazardous chemical processes, especially those that are key supervised hazardous chemical processes, are getting higher and higher. The "Guidelines for the Risk Assessment of Fine Chemical Reactions (Trial)" points out that for process hazards at levels 4 and 5, especially for projects with high risks but that must be industrialized, efforts should be made to prioritize process optimization or change the process method to reduce risks. For example, the reaction can be completed through microreactions or continuous flow.

[0003] In the fine chemical industry, there are often some reaction types with high viscosity, fast reaction speed, and large heat release. Our traditional continuous reaction devices, such as microchannel reaction devices and tubular reaction devices, are often helpless. Usually, problems such as blockage of the reaction device, poor heat exchange and mass transfer effects leading to a significant decrease in yield, poor efficiency of the reactor, and even safety risks are encountered.

[0004] Channel reactors have many advantages such as continuous operation, large specific surface area / volume ratio, significantly enhanced mass and heat transfer, rapid mixing, precise temperature control, small online liquid holdup, achieving inherent safety, no scale-up effect, shortened development cycle, and being more conducive to automatic control. They are often used to solve highly exothermic, unstable reactants or intermediates, and easily out-of-control chemical reactions [citing the microreaction-related patent and article "A Safe and Environmentally Friendly Nitration Reaction Microchannel Reaction Device": CN202221877610.1". Taghavi-Moghadam S, Kleemann A, Golbig G. Microreaction technology as a novel approach to drug design, process development and reliability[J], Organic Process Research & Development,. 2001, 5(6): 652-658]. However, due to the small channels of microchannel reactors, they are prone to blockage for solid-containing materials or materials with high viscosity. For materials with high viscosity, the pressure is too high, and due to high viscosity and slow flow rate, the heat and mass transfer efficiency of microchannel reactors drops significantly, and they are not suitable for gas-liquid phase reactions. The production capacity of this reaction device is small and the investment intensity is large, which greatly limits the application of microchannel reactors in the production of fine chemicals.

[0005] Tubular reactors have the advantages of large specific surface area / volume ratio, good heat and mass transfer effect, less liquid holdup, large production capacity, and relatively low investment intensity, making them a supplement to microchannel reactors in fine chemicals [citing patent for tubular reactors "A tubular reactor for producing ammonium persulfate": CN115282898B]]. However, tubular reactors cannot effectively solve reactions with high solid content, high viscosity, and high heat release, and have poor applicability to gas-liquid phase reactions, which limits their industrial application.

[0006] In recent years, the dynamic tubular reactor has been widely promoted in industry [citing the patent of dynamic tubular reactor of Haomai and other manufacturers or the article "A method for preparing 2,3-dichlorobenzaldehyde" CN107337276B], which improves its applicability to solid and high-viscosity materials by adding a stirring method. However, due to its general heat exchange capacity, even if an internal heat exchange channel is added, it cannot solve the reaction system with strong exothermic viscosity well. It has a general effect on gas-liquid mixing and poor applicability to gas-liquid reactions.

[0007] The circulating reactor that integrates a circulating pipe, a heat exchanger and a circulating pump can improve the heat exchange capacity of the reactor by forced circulation heat exchange. However, the mass transfer capacity of the reaction device is relatively weak. For rapid reactions and reactions with high viscosity, it is easy to produce local excessive temperatures, resulting in high impurities.

[0008] The solvent for the nitration reaction is often a solvent with a relatively high viscosity, such as sulfuric acid. The viscosity of the nitration raw material solution after dissolution is further increased. The viscosity of some nitration raw material solutions dissolved in sulfuric acid is as high as 200-800cp. The nitration reaction is often fast and releases a large amount of heat. If a microchannel or tubular reactor is directly used as a continuous nitration reaction device for direct reaction, it is not only prone to blockage and system overpressure, but also the material reacts instantly when it comes into contact with the nitrating agent. The large amount of heat released cannot be removed quickly in time, the local reaction temperature is too high, and the mixing effect is poor, resulting in a significant increase in impurities such as nitration isomers. Summary of the invention

[0009] The purpose of the present invention is to provide a novel continuous and efficient reaction device and an operating method thereof, which can effectively solve the reactions of gas-liquid phase, gas-liquid-solid phase, high viscosity, rapid reaction and strong heat release, and narrow reaction temperature range, and is also applicable to solid-free and low-viscosity reaction systems, especially to high-viscosity and strong heat release nitration reactions.

[0010] The purpose of the present invention can be achieved through the following technical solutions:

[0011] A novel continuous and efficient reaction device, comprising a first heat exchanger, a first pump, a second pump and corresponding connecting pipes and material inlets and outlets. The outlet of the first pump is connected to the inlet of the second pump through a pipe. The outlet of the second pump is connected to the inlet of the first heat exchanger. The outlet of the first heat exchanger is connected to the first feed inlet of the first pump. The first feed inlet is arranged at the front end of the inlet of the first pump. The feed of the second pump serves as the second feed inlet. A discharge outlet is arranged on the pipe of the first heat exchanger.

[0012] As a further scheme of the present invention: the first pump is a circulation pump, and the circulation pump is one of a centrifugal pump, an axial flow pump, a rotor pump, a gear pump, a screw pump, a canned motor pump, and a diaphragm pump;

[0013] The second pump is a mixing pump, and the mixing pump is one of a homogenizing pump, a grinding pump, an emulsifying pump, a centrifugal pump, an axial flow pump, a gear pump, and a rotor pump.

[0014] As a further scheme of the present invention: the first heat exchanger is one of a shell and tube heat exchanger, a wound heat exchanger, a plate heat exchanger, a disc heat exchanger, and a spiral plate heat exchanger.

[0015] As a further scheme of the present invention: the outlet of the second pump is connected to the inlet of the first heat exchanger. The outlet of the first heat exchanger is connected to the inlet of the third pump. The outlet of the third pump is connected to the inlet of the second heat exchanger. The feed of the third pump serves as the third feed inlet.

[0016] As a further scheme of the present invention: the third pump is a mixing pump, and the mixing pump is one of a homogenizing pump, a grinding pump, an emulsifying pump, a centrifugal pump, an axial flow pump, a gear pump, and a rotor pump;

[0017] The second heat exchanger is one of a shell and tube heat exchanger, a wound heat exchanger, a plate heat exchanger, a disc heat exchanger, and a spiral plate heat exchanger.

[0018] As a further scheme of the present invention: the homogenizing pump, the grinding pump, and the emulsifying pump adopt a moving disk and a static disk structure with multiple layers or a single layer of tooth disks. The tooth disks are straight teeth, helical teeth, and triangular teeth. The tooth disks are 1 - 5 layers, and the tooth pitch is 1 - 20 mm.

[0019] As a further scheme of the present invention: it is applied to the reactions of dangerous chemical processes such as nitrification, oxidation, peroxidation, fluorination, and chlorination.

[0020] As a further scheme of the present invention: it is applied to the reactions of dangerous chemical processes such as nitrification, oxidation, peroxidation, fluorination, and chlorination with high viscosity, fast reaction speed, and strong exothermic.

[0021] As a further scheme of the present invention: it is applied to the nitrification reaction with high viscosity, fast reaction speed, and strong exothermic.

[0022] As a further solution of the present invention: A method for operating a novel continuous and efficient reaction device, comprising the following steps:

[0023] Step 1: Open the cooling water inlet and outlet valves of Heat Exchanger 1, and open the top discharge port valve; Start Pump 1 and Pump 2; Feed the high-viscosity reaction liquid containing raw materials into the reaction device through Feed Port 1 21 with a metering pump, and close the Feed Port 1 valve; The volume of the material in Step 1 accounts for 30-80% of the reaction system, preferably 60-80%;

[0024] Step 2: Feed the reaction reagent into the reaction device through Feed Port 2 with a metering pump, and close the Feed Port 2 valve; The mixture is dispersed, sheared, and emulsified under the action of Pump 2; The material circulates under the action of the large-flow Pump 1, and the heat generated by the uniform reaction of the material is carried away by a large amount of products, and heat exchange and cooling are carried out in Heat Exchanger 1;

[0025] Step 3: Open Feed Port 1 and Feed Port 2, add the high-viscosity reaction liquid containing raw materials and the reaction reagent to the reaction device, and after the reaction is completed, the reaction liquid is discharged from the discharge port; The mass ratio of the materials in Feed Port 1, Feed Port 2, and the circulation pipeline between the two is 0.1:100 - 90:100.

[0026] During the above reaction process: The high-viscosity reaction liquid selectively contains raw materials, solvents, etc.; The reaction reagent is nitric acid; The raw material is 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II), and the solvent is one or a combination of sulfuric acid and nitric acid.

[0027] As a further solution of the present invention: A method for preparing 7-fluoro-6-nitro-2H-1,4-benzoxazin-3(4H)-one (I) from 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II) as a raw material in the presence of a nitrating reagent, and the reaction equation is as follows:

[0028]

[0029] Among them, the nitrating reagent is a combination of sulfuric acid and nitric acid;

[0030] The specific operation is as follows:

[0031] Step 1: Open the cooling water inlet and outlet valves of Heat Exchanger 1, and open the top discharge port valve; Start Pump 1 and Pump 2; Feed the sulfuric acid solution of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II) into the reaction device through Feed Port 1 with a metering pump, and close the Feed Port 1 valve; The volume of the material in Step 1 accounts for 30-80% of the reaction system;

[0032] Step 2: Feed nitric acid into the reaction device from Feed Port 2 using a metering pump, and close the valve of Feed Port 2. The mixture is dispersed, sheared, and emulsified under the action of Pump 2. The material circulates under the action of the large-flow Pump 1 until it is uniform. The heat generated by the reaction is carried away by a large amount of products and is cooled by heat exchange in Heat Exchanger 1.

[0033] Step 3: Open Feed Port 1 and Feed Port 2, add the sulfuric acid solution of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II) and nitric acid into the reaction device. After the reaction is completed, the reaction solution is discharged from the discharge port. The mass ratio of the materials in Feed Port 1, Feed Port 2, and the circulation pipeline between the two is 0.1:100 - 90:100.

[0034] Advantages of the present invention:

[0035] A homogenizing pump is a device that can efficiently, rapidly, and uniformly introduce one or more phases (liquid, solid, gas) into another immiscible continuous phase (usually liquid). The high tangential speed and high-frequency mechanical effects generated by the high-speed rotation of the stator and rotor of the homogenizing pump bring a strong mixing effect, causing the material to be subjected to strong mechanical and hydraulic shearing, centrifugal extrusion, liquid layer friction, impact tearing, and turbulence, etc. in the narrow gap between the stator and rotor, and being instantly and evenly finely dispersed and mixed, and the material is dispersed, sheared, and emulsified in a very short time. The use of a homogenizing pump greatly enhances the mass transfer and mixing effect. Especially for high-viscosity materials, in the material system where the mass transfer and mixing cannot be effectively improved by flow, static mixer, and conventional stirring, it can be well solved in the device of the present invention, realizing rapid and strong mixing and reaction.

[0036] The present invention realizes efficient heat exchange through forced circulation and forced stirring with a large flow rate. The material circulates under the action of the large-flow Pump 1. The heat generated by the reaction is carried away by a large amount of products, and further cooled by heat exchange in the heat exchanger. After cooling, part of the product of the material is discharged from the reaction system, and part of the product circulates in the reaction device. The mass ratio of the materials in Feed Port 1, Feed Port 2, and the circulation pipeline between the two is 0.1:100 - 20:100.

[0037] For traditional high-viscosity materials using the combination mode of a circulation pump or a mixing pump and a heat exchanger, due to the too high viscosity, it is impossible to ensure timely heat transfer. The addition of a dynamic reactor in the present invention further ensures the heat transfer and mass transfer effects, can avoid risks such as blockage and system overpressure, and at the same time can avoid the problem that the reaction occurs instantaneously when the material contacts the nitrating agent, the heat release is large and the heat cannot be removed in time and rapidly, resulting in too high local reaction temperature and poor mixing effect, leading to a significant increase in impurities such as nitration isomers. Description of the Drawings

[0038] The present invention will be further described below with reference to the drawings.

[0039] Figure 1 is the structural schematic diagram of the first embodiment of the present invention;

[0040] Figure 2 is the structural schematic diagram of the second embodiment of the present invention;

[0041] Figure 3 is the structural schematic diagram of Comparative Example 1 of the present invention;

[0042] Figure 4 is the structural schematic diagram of Comparative Example 3 of the present invention;

[0043] Figure 5 is the structural schematic diagram of Comparative Example 4 of the present invention. Detailed implementation manners

[0044] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0045] The present invention is a novel continuous and efficient reaction device.

[0046] The Reynolds number (Re) in the art is an important parameter for judging the fluid flow state. Generally speaking, when the Reynolds number Re > 4000, the fluid is in a turbulent state, and the mixing effect in this state is relatively ideal. It can be seen from the formula that compared with low-viscosity liquids, higher flow rates are required for high-viscosity liquids to reach the same Reynolds number (Re).

[0047]

[0048] Wherein:

[0049] - ρ is the liquid density

[0050] - v is the flow rate

[0051] - D is the pipe diameter

[0052] - μ is the liquid viscosity.

[0053] In the turbulent state (Reynolds number Re > 4000), according to the Fanning formula, it can be known that the pressure difference ΔP in the pipe is proportional to the square of the flow rate. Therefore, compared with low-viscosity liquids, when promoting high-viscosity liquids to reach the turbulent state in the pipe, the pressure in the pipe will rise sharply. This undoubtedly poses a great challenge to the reliability and stability of equipment such as transfer pumps, and the pressure resistance of equipment such as microreactors is also difficult to withstand such high pressures.

[0054]

[0055] Therefore, this solution innovatively adopts the forced mixing method of a hybrid pump to replace the traditional pipeline turbulent mixing, successfully overcoming the problem of excessive pressure during the pipeline turbulent mixing process.

[0056]

[0057] The specific operation is as follows:

[0058] Step 1: Open the cooling water inlet and outlet valves of the first heat exchanger 1, and open the valve of the top discharge port 11; start the first pump 2 and the second pump 3; use a metering pump to feed the sulfuric acid solution of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II) into the reaction device through the first feed port 21, and close the valve of the first feed port 21; the volume of the materials in Step 1 accounts for 60 - 80% of the reaction system;

[0059] Step 2: Feed nitric acid into the reaction device from the second feed port 31 using a metering pump, and close the valve of the second feed port 31; the mixed materials are dispersed, sheared, and emulsified under the action of the second pump 3; the materials circulate under the action of the large-flow first pump 2 until they are uniform, and the heat generated by the reaction is carried away by a large amount of products and exchanged and cooled in the first heat exchanger 1;

[0060] Step 3: Open the first feed port 21 and the second feed port 31, and feed the sulfuric acid solution of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (II) and nitric acid into the reaction device. After the reaction is completed, the reaction solution is discharged from the discharge port 11; the mass ratio of the materials in the first feed port 21, the second feed port 31, and the circulating pipeline between the two is 0.1:100 - 20:100.

[0061] Example 1

[0062] Please refer to Figure 1 As shown, the first heat exchanger 1 is a shell-and-tube heat exchanger, the first pump 2 is a centrifugal pump, and the second pump 3 is a homogenizing pump. The 28% raw material sulfuric acid solution is fed into the reaction device through the first feed port using a metering pump, and nitric acid is fed into the reaction device through the second feed port 31 using a metering pump. 28% raw material sulfuric acid solution: 67% nitric acid = 1:1.05 (molar ratio);

[0063] Specifically:

[0064] Open the cooling water inlet and outlet valves of the first heat exchanger 1, and open the valve of the top discharge port. Start the first pump 2 and the second pump 3. The 28% raw material sulfuric acid solution is fed into the reaction device through the first feed port 21 using a metering pump. After the total amount reaches 650 L, close the valve of the first feed port 21;

[0065] The nitric acid is fed into the reaction device from the second feed inlet 31 by a metering pump. After the total amount reaches 106 L, the valve of the second feed inlet 31 is closed;

[0066] After running for 5 minutes, the first feed inlet 21 and the second feed inlet 31 are opened simultaneously to feed 28% raw material sulfuric acid solution and 67% nitric acid into the reaction device. The mass ratio of the materials in the first feed inlet 21, the second feed inlet 31, and the circulating pipeline between them is 0.1:100 - 90:100. This mass ratio is preferably 0.1:100 - 50:100, and more preferably 0.1:100 - 20:100, indicating that less feed and more circulation are the best. The 28% raw material sulfuric acid solution is fed at flow rates 1 and 2 respectively, and at the same time, the flow rate of 67% nitric acid is controlled to ensure that the ratio of the flow rate of 28% raw material sulfuric acid solution to nitric acid = 1:1.05 (molar ratio);

[0067] Adjust the opening degree of the cooling water valve to control the temperature of the reaction device. The reaction liquid flows out from the discharge port 21. Samples are taken from the discharge port for detection and analysis; as shown in the following figure.

[0068]

[0069] Example 2

[0070] Please refer to Figure 2 Build a dynamic tubular reaction device as shown. Pump 1 is a centrifugal pump (flow rate is 20 m 3 / h), pump 2 and pump 3 are grinding pumps; heat exchanger 1 and heat exchanger 5 are both shell-and-tube heat exchangers.

[0071] The 28% raw material sulfuric acid solution is fed into the reaction device through the first feed inlet 21 by a metering pump. The 67% nitric acid is fed into the reaction device through the second feed inlet 31 and the third feed inlet 41 by a metering pump. The flow rate ratio of pump 2 to pump 3 is 1:1. 28% raw material sulfuric acid solution: 67% nitric acid = 1:1.05 (molar ratio);

[0072] Specifically:

[0073] Open the cooling water inlet and outlet valves and the top discharge port valve of heat exchanger 1 and heat exchanger 2. Start pump 1 (flow rate is 20 m 3 / h), pump 2, and pump 3. The raw material sulfuric acid solution enters the reaction device through the first feed inlet 21. After the total amount reaches 650 L, the valve of the first feed inlet 21 is closed.

[0074] The nitric acid enters the reaction device from the second feed inlet 31 and the third feed inlet 41 by a metering pump. The flow rate ratio of pump 2 to pump 3 is 1:1. After the total amount reaches 105 L, the valves of the second feed inlet 31 and the third feed inlet 41 are closed.

[0075] After running for 5 minutes, simultaneously open Feed Inlet 1 (21), Feed Inlet 2 (31), and Feed Inlet 3 (41). Control the flow rate of 67% nitric acid to ensure that the ratio of raw material sulfuric acid solution with a flow rate of 28% to nitric acid is 1:1.05 (molar ratio).

[0076] The reaction solution flows out from the discharge port. The product solution is sampled for detection and analysis; as shown in the figure below:

[0077]

[0078] Comparative Example 1

[0079] As Figure 3 shown: Set up a microchannel reaction device as shown. The raw material sulfuric acid solution and nitric acid enter the microchannel reactor through metering pumps P1 and P2.

[0080] Set the temperature of the microchannel reaction device to 25°C, and then use metering pumps P1 and P2 to simultaneously transport dilute nitric acid and 28% raw material sulfuric acid solution (viscosity 380 cp at 25°C) into the microchannel reaction device. Control the ratio of nitric acid to raw material solution to be 1:1.05 (molar ratio).

[0081] When nitric acid and the raw material sulfuric acid solution enter the microchannel, they start to mix and react. After passing through 4 modules, they flow into the reaction solution receiving bottle. After the volume of the outflowing reaction solution exceeds 100 ml, start "sampling HPLC" to analyze the content of the reaction solution. (The total volume of the pores in a single microchannel reaction device is 8.2 ml)

[0082] Test results:

[0083]

[0084] As the reaction progresses, the internal pores of the microchannel reaction device become blocked, and at the same time, the pressure gradually rises. After 10 minutes, the reaction device experiences overpressure.

[0085] Comparative Example 2

[0086] As Figure 3 shown: Set up a microchannel reaction device as shown.

[0087] Set the temperature of the microchannel reaction device to 30°C, and then use metering pumps P1 and P2 to simultaneously transport dilute nitric acid and raw material sulfuric acid solution (viscosity 300 cp at 30°C) into the microchannel reaction device. Control the ratio of nitric acid to raw material solution to be 1:1.05 (molar ratio).

[0088] When nitric acid and the raw material sulfuric acid solution enter the microchannel, they start to mix and react. After passing through 4 modules, they flow into the reaction solution receiving bottle. After the volume of the outflowing reaction solution exceeds 100 ml, start sampling HPLC to analyze the content of the reaction solution. (The total volume of the pores in a single microchannel reaction device is 8.2 ml)

[0089] Test results:

[0090]

[0091]

[0092] As the reaction proceeded, the internal channels of the microchannel reactor became blocked, and at the same time, the pressure gradually increased. After 10 minutes, the reactor experienced overpressure.

[0093] Comparative Example 3

[0094] As Figure 4 shown, a dynamic tubular reactor was set up. The raw material sulfuric acid solution was transported through metering pump 1, and nitric acid was transported through metering pumps 2 and 3.

[0095] The cooling outer circulation of the dynamic tubular reactor was started, and then dilute nitric acid and the raw material sulfuric acid solution (viscosity 380 cp at 25°C) were simultaneously transported into the microchannel reactor using metering pumps P1 and P2. The ratio of nitric acid to the raw material solution was controlled at 1:1.07 (molar ratio).

[0096] Nitric acid and the raw material sulfuric acid solution entered the dynamic tubular reactor (internal volume 1.5 L). A mixed reaction occurred, and the reaction solution entered the collection bottle. The opening degree of the external circulation cooling water valve was controlled to keep the reaction temperature around 25°C; the rotation speed of the dynamic tubular reactor was controlled at 300 r / min. The flow rate of the raw material solution was 54 ml / min, and the flow rate of nitric acid was 7.8 ml / min.

[0097] After the volume of the outflowing reaction solution exceeded 4.5 L, "sampling HPLC" was started to analyze the content of the reaction solution.

[0098] Test results:

[0099] Serial number Raw material / % Product / % Isomer / % Dinitro impurity / % Temperature 1 / °C Temperature 2 / °C Sample 1: (30 minutes) 4.14 88.39 2.61 0.84 27.1 21.6 Sample 2: (60 minutes) 4.28 88.7 2.37 0.93 28.5 22.7 Control batch in autoclave ＜0.5％ 94％ ＜0.8％ ＜0.8％

[0100] Comparative Example 4

[0101] As Figure 5 shown, a dynamic tubular reactor was set up. The raw material sulfuric acid solution was transported through metering pump 1, and nitric acid was transported through metering pumps 2 and 3.

[0102] The cooling outer circulation of the dynamic tubular reactor was started, and then the raw material sulfuric acid solution (viscosity 380 cp at 25°C) and dilute nitric acid were simultaneously transported into the microchannel reactor using metering pumps P1 and P2. After the dynamic tubular reactor had outflowing reaction solution, metering pump P3 was started. The ratio of nitric acid to the raw material solution was controlled at 1:1.07 (molar ratio), and the flow rate ratio of metering pumps 2 and 3 was 1:1.

[0103] The material undergoes a reaction in a dynamic tubular reaction device, and the reaction solution enters the collection device. Control the opening degree of the external circulation cooling water valve to control the reaction temperature at about 25°C; control the rotation speed of the dynamic tubular reaction device at 300 r / min. Flow rate of the raw material liquid: 54 ml / min Total flow rate of nitric acid: 7.8 ml / min

[0104] After the volume of the outflowing reaction solution exceeds 4.5 L, start the "sampling HPLC" analysis of the content of the reaction solution.

[0105] Test results:

[0106] Serial number Raw material / % Product / % Isomer / % Dinitro impurity / % Temperature 1 / °C Temperature 2 / °C Sample 1: (30 minutes) 1.54 86.9 2.31 1.47 27.1 25.4 Sample 2: (60 minutes) 2.08 86.7 2.25 1.54 27.5 25.1 Control batch in autoclave ＜0.5％ 94％ ＜0.8％ ＜0.8％

[0107] The above has described a specific embodiment of the present invention in detail, but the described content is only the preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the present invention application shall still fall within the scope covered by the patent of the present invention.

Claims

1. A novel continuous and efficient reaction device, characterized in that It includes a first heat exchanger (1), a first pump (2), a second pump (3), and corresponding connecting pipes and material inlets and outlets. The outlet of the first pump (2) is connected to the inlet of the second pump (3) through a pipe. The outlet of the second pump (3) is connected to the inlet of the first heat exchanger (1). The outlet of the first heat exchanger (1) is connected to the first feed inlet (21) of the first pump (2). The first feed inlet (21) is arranged at the front end of the inlet of the first pump (2). The feed of the second pump (3) serves as the second feed inlet (31). A discharge outlet (11) is arranged on the pipe of the first heat exchanger (1).

2. A novel continuous and efficient reaction device according to claim 1, characterized in that, The first pump (2) is a circulating pump, and the circulating pump is one of a centrifugal pump, an axial flow pump, a rotor pump, a gear pump, a screw pump, a canned motor pump, and a diaphragm pump; The second pump (3) is a mixing pump, and the mixing pump is one of a homogenizing pump, a grinding pump, an emulsifying pump, a centrifugal pump, an axial flow pump, a gear pump, and a rotor pump.

3. A novel continuous high-efficiency reaction device according to claim 1, characterized in that, The first heat exchanger (1) is one of a shell and tube heat exchanger, a wound heat exchanger, a plate heat exchanger, a disk heat exchanger, and a spiral plate heat exchanger.

4. A novel continuous and efficient reaction device according to claim 1, characterized in that, The outlet of the second pump (3) is connected to the inlet of the first heat exchanger (1). The outlet of the first heat exchanger (1) is connected to the inlet of the third pump (4). The outlet of the third pump (4) is connected to the inlet of the second heat exchanger (5). The feed of the third pump (4) serves as the third feed inlet (41).

5. A novel continuous and efficient reaction device according to claim 4, characterized in that, The third pump (4) is a mixing pump, and the mixing pump is one of a homogenizing pump, a grinding pump, an emulsifying pump, a centrifugal pump, an axial flow pump, a gear pump, and a rotor pump; The second heat exchanger (5) is one of a shell and tube heat exchanger, a wound heat exchanger, a plate heat exchanger, a disk heat exchanger, and a spiral plate heat exchanger.

6. A novel continuous and highly efficient reaction device according to claim 2, characterized in that, The homogenizing pump, the grinding pump, and the emulsifying pump adopt a moving disk and a static disk structure with multiple or single-layer tooth disks. The tooth disks are straight teeth, helical teeth, and triangular teeth. The tooth disks are 1 - 5 layers, and the tooth pitch is 1 - 20 mm.

7. A novel continuous high-efficiency reaction device according to claim 1, characterized in that, It is applied to the reactions of dangerous chemical processes such as nitrification, oxidation, peroxidation, fluorination, and chlorination.

8. A novel continuous and efficient reaction device according to claim 1, characterized in that, It is applied to the reactions of dangerous chemical processes such as nitrification, oxidation, peroxidation, fluorination, and chlorination with high viscosity, fast reaction rate, and strong exothermicity.

9. A novel continuous high-efficiency reaction device according to claim 1, characterized in that, It is applied to the nitrification reaction with high viscosity, fast reaction rate, and strong exothermicity.

10. A method for operating a new type of continuous and efficient reaction device, characterized in that, It includes the following steps: Step 1: Open the cooling water inlet and outlet valves of the first heat exchanger (1), and open the valve of the top discharge outlet (11); Start the first pump (2) and the second pump (3); Feed the high-viscosity reaction liquid containing raw materials into the reaction device through the first feed inlet (21) with a metering pump, and close the valve of the first feed inlet (21); The volume of the materials in Step 1 accounts for 30 - 80% of the reaction system; Step 2: Feed the reaction reagent into the reaction device from the second feed inlet (31) with a metering pump, and close the valve of the second feed inlet (31); The mixture is dispersed, sheared, and emulsified under the action of the second pump (3); The materials circulate under the action of the large-flow first pump (2) until they are uniform, and the heat generated by the reaction is carried away by a large amount of products and heat exchange and cooling are carried out in the first heat exchanger (1); Step 3: Open the first feed inlet (21) and the second feed inlet (31), add a high-viscosity reaction solution containing raw materials and a reaction reagent to the reaction device, and after the reaction is completed, the reaction solution is discharged from the discharge port (11); the mass ratio of the materials in the first feed inlet (21), the second feed inlet (31) and the circulation pipeline between the two is 0.1:100 - 90:100.

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