A continuous flow microreaction method and production equipment for preparing nano-α-MnO2

Abstract

The application discloses a continuous flow micro-reaction preparation method and production equipment of nano alpha-MnO2, relates to the technical field of chemical equipment, and comprises a system framework, a control system is installed on the upper end of the system framework, a first feeding conveying system is fixedly installed on the upper end of the system framework, a first liquid inlet channel is arranged in the first feeding conveying system, a first liquid inlet valve is arranged on the first liquid inlet channel, a micro-reaction system is fixedly arranged on one side of the system framework, a second feeding conveying system is fixed on the other side of the system framework, and the first feeding conveying system and the second feeding conveying system are both connected with the micro-reaction system.

Description

Technical Field

[0001] This invention relates to the field of chemical equipment technology, specifically a continuous flow microreaction preparation method and production equipment for nano α-MnO2. Background Technology

[0002] α-MnO2, a nanomaterial, is an important transition metal oxide with excellent electrochemical and catalytic properties, and is widely used in chemical synthesis and production. Compared with traditional batch reactions, continuous flow reactions offer higher production efficiency and better product quality. However, existing preparation methods, such as chemical precipitation, sol-gel methods, and electrochemical methods, suffer from problems such as complex preparation processes, high costs, and difficulty in large-scale production. Furthermore, their poor mixing efficiency during hydrothermal reactions can negatively impact the chemical reaction rate.

[0003] Therefore, it is necessary to provide a continuous flow microreaction preparation method and production equipment for nano-α-MnO2 to solve the problems mentioned in the background art. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides the following technical solution: a continuous flow microreaction preparation method and production equipment for nano-α-MnO2, comprising:

[0005] The system framework, on which the control system is installed;

[0006] A first feeding and conveying system is fixedly installed at the upper end of the system frame, and a first liquid inlet channel is arranged inside it, with a first liquid inlet valve installed on the first liquid inlet channel; and

[0007] A micro-reaction system is fixedly installed on one side of the system frame, and a second feeding conveying system is fixed on the other side of the system frame. Both the first feeding conveying system and the second feeding conveying system are connected to the micro-reaction system.

[0008] Furthermore, as a preferred embodiment, the first feeding conveying system and the second feeding conveying system are both independent liquid supply systems, and each is supplied with liquid by a liquid supply mechanism connected to itself.

[0009] Furthermore, as a preferred embodiment, the second feeding conveying system includes:

[0010] The mounting base is fixedly installed within the system frame. It has three separate flow-blocking layers inside, and a second liquid inlet channel is installed at the upper end of the mounting base. A second liquid inlet valve for controlling the flow of solution is installed on the second liquid inlet channel.

[0011] Layered flow channels are fixedly installed on the three flow-blocking layers respectively;

[0012] The distribution channel is fixed to one side of the mounting base and is connected to the second liquid inlet channel through the layered guide channel.

[0013] Furthermore, as a preferred embodiment, the layered flow channel includes a first flow channel, a second flow channel, and a third flow channel, which are respectively fixedly installed on the three flow-blocking layers.

[0014] Furthermore, as a preferred embodiment, the flow path tolerance of the first flow guide channel, the second flow guide channel, and the third flow guide channel is: S is an arithmetic sequence.

[0015] Furthermore, as a preferred embodiment, the distribution channel includes a first channel connected to the first guide channel, a second channel connected to the second guide channel, and a third channel connected to the third guide channel, and the first channel, the second channel, and the third channel are all connected to the micro-reaction system.

[0016] Furthermore, as a preferred embodiment, the first channel, the second channel, and the third channel are each equipped with a corresponding first valve body, a second valve body, and a third valve body.

[0017] Furthermore, preferably, the microreaction system includes:

[0018] The reaction chamber is fixedly installed within the system frame, and a heating layer for heating is provided inside it;

[0019] The discharge channel is located on one side of the reaction chamber, and the discharge channel has a liquid outlet valve.

[0020] Furthermore, as a preferred embodiment, a first liquid level detection device is provided in the reaction chamber and at the same level as the lower end of the first valve body, and a second liquid level detection device is provided at the top of the reaction chamber.

[0021] A method for preparing a microfluidic feeding device for the production of nano-α-MnO2 includes the following steps:

[0022] S1: First, inject 0.10-1.10 mol / L KMnO4 solution into the first feeding and conveying system;

[0023] S2: Close the first valve body, the second valve body and the third valve body, and open the first liquid inlet valve to inject a certain amount of KMnO4 solution into the reaction chamber;

[0024] S3: Open the second inlet valve, the first valve body, the second valve body and the third valve body, close the first inlet valve, and inject 0.08-1.20 mol / L MnSO4∙H2O solution into the reaction chamber. The MnSO4∙H2O solution flows into the reaction chamber along the first guide channel and flows upward, so that the bottom KMnO4 solution is passively mixed by the MnSO4∙H2O solution.

[0025] S4: After the first liquid level detection device detects the fixed liquid level, the first liquid inlet valve is opened, and the first liquid inlet channel continues to inject KMnO4 solution into the reaction chamber at a fixed flow rate. Meanwhile, the 0.08-1.20 mol / L MnSO4∙H2O solution, as a continuous flow, continues to flow along the second and third guide channels and is mixed with the KMnO4 solution flowing into the reaction chamber by impact, in conjunction with the passive impact mixing of the two-phase solution rising from the bottom.

[0026] S5: After the second liquid level detection device detects the fixed liquid level, close the first inlet valve, the second inlet valve, the first valve body, the second valve body and the third valve body to stop the liquid supply;

[0027] S6: The heating layer is activated, and the two-phase solution undergoes high-temperature pressure and hydrothermal reaction within the micro-reaction system;

[0028] S7: After the two-phase solution is maintained at 90-100℃ for 3-5 hours in the micro-reaction system, the liquid outlet valve is opened and the reaction mixture is discharged through the discharge channel. Finally, the collected reaction mixture is washed and dried to obtain nano α-MnO2.

[0029] Compared with existing technologies, this invention provides a continuous flow microreaction preparation method and production equipment for nano-α-MnO2, which has the following beneficial effects:

[0030] In this invention, the equipment first supplies a quantitative amount of reaction base liquid to the reaction chamber through a first feeding and conveying system. Then, reaction liquid is injected into the reaction chamber according to the different paths of the first, second, and third guide channels. That is, the reaction liquid enters the reaction chamber in a continuous flow manner, and the time difference of entering the reaction chamber is different. Thus, the bottom reaction base liquid is passively impact-mixed by the reaction liquid. The reaction base liquid continues to be supplied to the reaction chamber. The subsequent two-phase solutions can be effectively mixed by counter-impact within a certain liquid level range, combined with the passive impact mixing of the rising two-phase solutions at the bottom, thereby promoting the mixing effect of the two-phase solutions and improving the simplicity of the preparation process. At the same time, multiple sets of equipment can be set up to carry out the reaction together, which is conducive to the mass production of products. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of a continuous flow microreactor production device for nano-α-MnO2;

[0032] Figure 2 This is a schematic diagram of the second feeding and conveying system in a continuous flow microreactor for the production of nano-α-MnO2;

[0033] Figure 3 for Figure 2 Schematic diagram of the first guide channel structure;

[0034] Figure 4 for Figure 2 Schematic diagram of the second guide channel structure;

[0035] Figure 5 for Figure 2 Schematic diagram of the third guide channel structure;

[0036] Figure 6 This is a schematic diagram of the microreaction system in a continuous flow microreaction production device for nano-α-MnO2;

[0037] In the diagram: 1. System framework; 2. First feeding and conveying system; 3. Micro-reaction system; 4. Second feeding and conveying system; 21. First liquid inlet channel; 31. Reaction chamber; 32. Discharge channel; 41. Mounting base shell; 42. Flow barrier; 43. Second liquid inlet channel; 44. First channel; 45. Second channel; 46. Third channel; 471. First guide channel; 472. Second guide channel; 473. Third guide channel. Detailed Implementation

[0038] Please see Figures 1-6 In this embodiment of the invention, a continuous flow microreactor production device for nano-α-MnO2 includes:

[0039] System framework 1, on which a control system is installed;

[0040] A first feeding and conveying system 2 is fixedly installed on the upper end of the system frame 1, and a first liquid inlet channel 21 is arranged inside it, with a first liquid inlet valve installed on the first liquid inlet channel 21; and

[0041] The micro-reaction system 3 is fixedly installed on one side of the system frame 1, and the second feeding conveying system 4 is fixed on the other side of the system frame 1. The first feeding conveying system 2 and the second feeding conveying system 4 are respectively connected to the micro-reaction system 3.

[0042] In practical use, a quantitative amount of 0.10-1.10 mol / L KMnO4 solution is injected into the microreaction system 3 through the first feeding system 2, and then the supply of KMnO4 solution is stopped. The 0.10-1.10 mol / L KMnO4 solution then serves as the dispersed phase. Next, a 0.08-1.20 mol / L MnSO4·H2O solution is continuously injected into the microreaction system 3 through the second feeding system 4. The 0.08-1.20 mol / L MnSO4·H2O solution serves as the continuous phase. At this point, the KMnO4 solution is at the bottom, and the MnSO4·H2O solution continuously impacts the KMnO4 solution upwards, causing the bottom KMnO4 solution to be passively mixed by the MnSO4·H2O solution. Once a fixed liquid level is reached, the 0.10-1.10 mol / L KMnO4 solution is injected into the microreaction system 3 again through the first feeding system 2. KMnO4 solution is continuously injected into the micro-reaction system 3 by the second feeding system 4, while MnSO4∙H2O is continuously injected into the micro-reaction system 3. The MnSO4∙H2O solution and KMnO4 solution are mixed by impact, and the two-phase solution rises from the bottom by passive impact mixing. After reaching a fixed liquid level, both the first feeding system 2 and the second feeding system 4 stop supplying liquid. The two-phase solution undergoes high-temperature pressure and hydrothermal reaction in the micro-reaction system 3. After the two-phase solution is maintained at 90-100℃ for 3-5 hours in the micro-reaction system 3, the reaction mixture is collected and washed and dried to obtain nano α-MnO2.

[0043] In a preferred embodiment, the first feeding conveying system 2 and the second feeding conveying system 4 are both independent liquid supply systems, and they are respectively supplied by their own liquid supply mechanisms. That is, the first feeding conveying system 2 is connected to a liquid supply mechanism that can transport 0.10-1.10 mol / L KMnO4 solution, and the second feeding conveying system 4 is connected to a liquid supply mechanism that can transport 0.08-1.20 mol / L MnSO4∙H2O solution.

[0044] Please see Figure 2 , Figure 3 In this embodiment, the second feeding and conveying system 4 includes:

[0045] The mounting base 41 is fixedly installed inside the system frame 1. It has three mutually separated flow-blocking layers 42 inside, and a second liquid inlet channel 43 is installed at the upper end of the mounting base 41. A second liquid inlet valve for controlling the flow of solution is installed on the second liquid inlet channel 43.

[0046] Layered flow channels are fixedly installed on the three flow-blocking layers 42 respectively;

[0047] The distribution channel is fixed to one side of the mounting base 41 and is connected to the second liquid inlet channel 43 through the layered guide channel.

[0048] In other words, the MnSO4∙H2O solution enters the layered guide channel through the second inlet channel 43, and then enters each distribution channel. The injection and cessation of the MnSO4∙H2O solution in the layered guide channel are controlled by the second inlet valve.

[0049] Please see Figure 3 , Figure 4 , Figure 5 In this embodiment, the layered flow channel includes a first flow channel 471, a second flow channel 472, and a third flow channel 473, which are respectively fixedly installed on the three flow-blocking layers 42.

[0050] It should be explained that the first guide channel 471, the second guide channel 472, and the third guide channel 473 are connected to the second liquid inlet channel 43 through a three-way pipe.

[0051] In a preferred embodiment, the flow path tolerance of the first guide channel 471, the second guide channel 472, and the third guide channel 473 is: The arithmetic sequence S indicates that the starting times for the injection of MnSO4∙H2O solution into the microreaction system 3 by the first guide channel 471, the second guide channel 472, and the third guide channel 473 are different. In other words, the second guide channel 472 and the third guide channel 473 can buffer a certain amount of MnSO4∙H2O solution, so that the first guide channel 471 supplies the microreaction system 3 first, and the second guide channel 472 and the third guide channel 473 then supply the microreaction system 3 with MnSO4∙H2O solution in sequence within a certain time difference.

[0052] Please see Figure 2 In this embodiment, the distribution channel includes a first channel 44 connected to the first guide channel 471, a second channel 45 connected to the second guide channel 472, and a third channel 46 connected to the third guide channel 473, and the first channel 44, the second channel 45, and the third channel 46 are all connected to the micro-reaction system 3.

[0053] It should be explained that the relative distance between the first inlet channel 21 and the first channel 44 is relatively large. If the KMnO4 solution and MnSO4·H2O solution are directly mixed by an impact mixing method, the two liquid phases will first impact each other in a strip-like manner, resulting in a small contact area. However, by using passive impact mixing, the liquid column of MnSO4·H2O solution will disperse and flow in the KMnO4 solution during injection, resulting in a higher mixing efficiency compared to the impact mixing method. Furthermore, the subsequent impact mixing of KMnO4 solution and MnSO4·H2O solution, combined with the passive impact mixing of the bottom layer mixture, ensures that both the upper and lower layer solutions can make sufficient contact.

[0054] In a preferred embodiment, the first channel 44, the second channel 45, and the third channel 46 are each equipped with a corresponding first valve body, a second valve body, and a third valve body. That is, the first valve body controls the injection or cessation of MnSO4∙H2O solution in the first channel 44, the second valve body controls the injection or cessation of MnSO4∙H2O solution in the second channel 45, and the third valve body controls the injection or cessation of MnSO4∙H2O solution in the third channel 46. When MnSO4∙H2O solution is continuously supplied, the first, second, and third valve bodies are all open. Only when the KMnO4 solution and MnSO4∙H2O solution reach the contents of the micro-reaction system 3, that is, when the hydrothermal reaction is finally carried out, the first, second, and third valve bodies are all closed. At this time, a closed space is provided for the micro-reaction system 3, which is beneficial for the high-temperature pressure buildup during the two-phase solution reaction.

[0055] Please see Figure 6 In this embodiment, the microreaction system 3 includes:

[0056] The reaction chamber 31 is fixedly installed within the system frame 1, and a heating layer for heating is provided inside it;

[0057] The discharge channel 32 is located on one side of the reaction chamber 31, and the discharge channel 32 has a liquid outlet valve;

[0058] It should be noted that the heating layer provides a suitable temperature (90-100℃) for the two-phase solution reaction, so as to improve the chemical reaction rate and ensure a complete reaction.

[0059] In a preferred embodiment, a first liquid level detection device is provided inside the reaction chamber 31 and flush with the lower end of the first valve body, and a second liquid level detection device is provided at the top of the reaction chamber 31.

[0060] In other words, after the first liquid level detection device detects that the two-phase solution has reached a fixed liquid level at the beginning, the feedback control system controls the opening of the first liquid inlet valve, thereby controlling the KMnO4 solution to continue to be injected into the reaction chamber 31. After the second liquid level detection device detects the maximum liquid level of the two-phase solution reaction chamber 31, the feedback control system controls the complete closure of the first liquid inlet valve, the second liquid inlet valve, the first valve body, the second valve body and the third valve body, so that the reaction chamber 31 is in a sealed space.

[0061] It needs to be explained that, after closing the first, second, and third valve bodies and opening the first inlet valve, a measured amount of KMnO4 solution is injected into the reaction chamber 31 through the first feed conveying system 2. At this point, the KMnO4 solution is in zone I, and the volume of the solution in zone I is V1. Then, the second inlet valve, the first valve body, the second valve body, and the third valve body are opened, and the first inlet valve is closed, injecting 0.08-1.20 mol / L solution into the reaction chamber 31. After the first liquid level detection device detects a fixed liquid level, the volume of the injected MnSO4·H2O solution is V2. The solution in zone II is the KMnO4 solution from zone I, which has undergone passive impact mixing with the MnSO4·H2O solution, resulting in a two-phase mixture rising to a certain height. Then, the first inlet valve is opened, and the first inlet channel 21 continues to inject KMnO4 solution into the reaction chamber 31 at a fixed flow rate. The MnSO4·H2O solution, as a continuous flow, continues along the different paths of the second guide channel 472 and the third guide channel 473, and undergoes impact mixing with the KMnO4 solution entering the reaction chamber 31. This, combined with the passive impact mixing of the two-phase solution rising from the bottom, results in the following: the volume of zone III in reaction chamber 31 is V3 of KMnO4 solution and 2V4 of MnSO4·H2O solution; the volume of zone IV in reaction chamber 31 is V5 of KMnO4 solution and 3V6 of MnSO4·H2O solution. Figure 6 As shown;

[0062] That is, the chemical reaction formula for the reaction between KMnO4 solution and MnSO4∙H2O solution in reaction chamber 31 is:

[0063] 2KMnO4+3MnSO4+2H2O→5MnO2↓+K2SO4+2H2SO4

[0064] Therefore, the volume ratios of the two-phase solutions injected into reaction chamber 31 are as follows:

[0065] V 1： V2=2:3

[0066] V3:2V4=2:3

[0067] V5: 3V6 = 2:3

[0068] V1=V3=nV5

[0069] V2=2V4= V6

[0070] V1 — Volume of KMnO4 solution in zone I;

[0071] V2—Volume of MnSO4∙H2O solution in zone II;

[0072] V3—Volume of KMnO4 solution in Zone III;

[0073] 2V4—Volume of MnSO4∙H2O solution in Zone III;

[0074] V5 – Volume of KMnO4 solution in zone IV;

[0075] 3V6 — Volume of MnSO4∙H2O solution in zone IV;

[0076] n—the volume ratio of KMnO4 solution in zone IV to KMnO4 solution in zone III;

[0077] The volume difference between the second guide channel 472 and the first guide channel 471 is V2, and the volume difference between the third guide channel 473 and the second guide channel 472 is 2V4, which is equal to V2. During the liquid supply process, at least (2+) are injected into the reaction chamber 31. )V1 KMnO4 solution and (2+ The first injection of MnSO4∙H2O solution from V2 into reaction chamber 31 was a KMnO4 solution from V1. The second injection of (1+)MnSO4∙H2O solution into reaction chamber 31 was a KMnO4 solution from V1. The KMnO4 solution of V1 is continuously injected into the reaction chamber 31 in this process (2+) V2 of MnSO4∙H2O solution;

[0078] In practical use, the first feeding and conveying system 2 can be connected in series with multiple micro-reaction systems 3. The micro-reaction systems 3 are connected in series with the second feeding and conveying system 4. Then, the volume of liquid supply is equal to the number of steps fed to the micro-reaction systems 3 and is evenly divided into one-tenth of the corresponding number of micro-reaction systems 3, which is beneficial to the mass production of nano α-MnO2.

[0079] A method for preparing a microfluidic feeding device for the production of nano-α-MnO2 includes the following steps:

[0080] S1: First, inject 0.10-1.10 mol / L KMnO4 solution into the first feeding and conveying system 2;

[0081] S2: Close the first valve body, the second valve body and the third valve body, and open the first liquid inlet valve to inject a certain amount of KMnO4 solution into the reaction chamber 31;

[0082] S3: Open the second inlet valve, the first valve body, the second valve body and the third valve body, close the first inlet valve, and inject 0.08-1.20 mol / L MnSO4∙H2O solution into the reaction chamber 31. The MnSO4∙H2O solution flows into the reaction chamber 31 along the first guide channel 471 and flows upward, so that the bottom KMnO4 solution is passively mixed by the MnSO4∙H2O solution.

[0083] S4: After the first liquid level detection device detects the fixed liquid level, the first liquid inlet valve is opened, and the first liquid inlet channel 21 continues to inject KMnO4 solution into the reaction chamber 31 at a fixed flow rate. Meanwhile, the 0.08-1.20 mol / L MnSO4∙H2O solution, as a continuous flow, continues to flow along the second guide channel 472 and the third guide channel 473 to mix with the KMnO4 solution flowing into the reaction chamber 31 in a counter-impact manner, in conjunction with the passive impact mixing of the two-phase solution rising from the bottom.

[0084] S5: After the second liquid level detection device detects the fixed liquid level, close the first inlet valve, the second inlet valve, the first valve body, the second valve body and the third valve body to stop the liquid supply;

[0085] S6: Start the heating layer, and the two-phase solution undergoes high-temperature pressure and hydrothermal reaction in the micro-reaction system 3;

[0086] S7: After the two-phase solution is maintained at 90-100℃ for 3-5 hours in the micro-reaction system 3, the liquid outlet valve is opened and the reaction mixture is discharged through the discharge channel 32. Finally, the collected reaction mixture is washed and dried to obtain nano α-MnO2.

[0087] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A continuous flow microreactor production device for nano-α-MnO2, characterized in that: It includes: The system framework (1) has a control system installed on its upper part; A first feeding conveying system (2) is fixedly installed at the upper end of the system frame (1), and a first liquid inlet channel (21) is arranged inside it, with a first liquid inlet valve installed on the first liquid inlet channel (21); and The micro-reaction system (3) is fixedly installed on one side of the system frame (1), and the other side of the system frame (1) is fixedly provided with a second feeding conveying system (4), and the first feeding conveying system (2) and the second feeding conveying system (4) are respectively connected to the micro-reaction system (3); The second feeding conveyor system (4) includes: The mounting base (41) is fixedly installed in the system frame (1). It has three mutually separated flow isolation layers (42) inside, and a second liquid inlet channel (43) is installed at the upper end of the mounting base (41). A second liquid inlet valve for controlling the flow of solution is installed on the second liquid inlet channel (43). Layered flow channels are fixedly installed on the three flow-blocking layers (42); The distribution channel is fixed to one side of the mounting base (41) and is connected to the second liquid inlet channel (43) through the layered guide channel; The layered flow channel includes a first flow channel (471), a second flow channel (472), and a third flow channel (473) that are respectively fixedly installed on the three flow-blocking layers (42); The flow paths of the first guide channel (471), the second guide channel (472), and the third guide channel (473) are an arithmetic sequence with a common difference of ΔS. The distribution channel includes a first channel (44) connected to the first guide channel (471), a second channel (45) connected to the second guide channel (472), and a third channel (46) connected to the third guide channel (473), and the first channel (44), the second channel (45), and the third channel (46) are all connected to the micro-reaction system (3); The micro-reaction system (3) includes a reaction chamber (31). The device first supplies a quantitative amount of reaction base liquid to the reaction chamber (31) through the first feeding and conveying system (2). Then, according to the different paths of the first guide channel (471), the second guide channel (472), and the third guide channel (473), the reaction liquid is injected into the reaction chamber (31). That is, the reaction liquid enters the reaction chamber (31) in a continuous flow manner, and the time difference of entering the reaction chamber (31) is different. Thus, the bottom reaction base liquid is passively impact-mixed by the reaction liquid. The reaction base liquid continues to be supplied to the reaction chamber (31). Subsequently, the two-phase solution is subjected to counter-impact mixing and passive impact mixing with the two-phase solution rising from the bottom.

2. The continuous flow microreactor production equipment for nano-α-MnO2 according to claim 1, characterized in that: The first feeding conveying system (2) and the second feeding conveying system (4) are both independent liquid supply systems, and they are respectively supplied by their own liquid supply mechanisms.

3. The continuous flow microreactor production equipment for nano-α-MnO2 according to claim 1, characterized in that: The first channel (44), the second channel (45), and the third channel (46) are each equipped with a corresponding first valve body, second valve body, and third valve body.

4. The continuous flow microreactor production equipment for nano-α-MnO2 according to claim 3, characterized in that: The micro-reaction system (3) also includes a discharge channel (32). The reaction chamber (31) is fixedly installed in the system frame (1) and has a heating layer inside it that can be used for heating. The discharge channel (32) is opened on one side of the reaction chamber (31) and is equipped with a liquid discharge valve.

5. The continuous flow microreactor production equipment for nano-α-MnO2 according to claim 4, characterized in that: A first liquid level detection device is provided inside the reaction chamber (31) and flush with the lower end of the first valve body, and a second liquid level detection device is provided at the top of the reaction chamber (31).

6. A continuous flow microreactor production method for nano-α-MnO2, employing a continuous flow microreactor production equipment for nano-α-MnO2 as described in any one of claims 1-5, characterized in that, Includes the following steps: S1: First inject 0.10-1.10 mol / L KMnO4 solution into the first feeding conveying system (2); S2: Close the first valve body, the second valve body and the third valve body, and open the first liquid inlet valve to inject a certain amount of KMnO4 solution into the reaction chamber (31); S3: Open the second inlet valve, the first valve body, the second valve body and the third valve body, close the first inlet valve, and inject 0.08-1.20mol / L MnSO4·H2O solution into the reaction chamber (31). The MnSO4·H2O solution flows into the reaction chamber (31) along the first guide channel (471) and flows upward, so that the bottom KMnO4 solution is passively impacted and mixed by the MnSO4·H2O solution. S4: After the first liquid level detection device detects the fixed liquid level, the first liquid inlet valve is opened, and the first liquid inlet channel (21) continues to inject KMnO4 solution into the reaction chamber (31) at a fixed flow rate. Meanwhile, the 0.08-1.20mol / L MnSO4·H2O solution is continuously flowing along the second guide channel (472) and the third guide channel (473) to mix with the KMnO4 solution flowing into the reaction chamber (31) in a counter-impact manner, in conjunction with the passive impact mixing of the two-phase solution rising from the bottom. S5: After the second liquid level detection device detects the fixed liquid level, close the first inlet valve, the second inlet valve, the first valve body, the second valve body and the third valve body to stop the liquid supply; S6: Start the heating layer, and the two-phase solution undergoes high-temperature pressure and hydrothermal reaction in the micro-reaction system (3); S7: After the two-phase solution is maintained at 90-100℃ for 3-5 hours in the micro-reaction system (3), the liquid outlet valve is opened and the reaction mixture is discharged through the discharge channel (32). Finally, the collected reaction mixture is washed and dried to obtain nano α-MnO2.

Images