A continuous flow microreaction velocity control system and preparation method for the preparation of nano-β-MnO2

Abstract

This invention discloses a continuous flow microreactor flow rate control system and preparation method for the preparation of nano-β-MnO2, comprising a base, a first injection tube, a second injection tube, a microfluidic mechanism, and a collection mechanism. The first and second injection tubes are both fixedly mounted on the base, each containing a first reaction solution and a second reaction solution, respectively. The microfluidic mechanism is fixedly mounted on the base and communicates with the first and second injection tubes. A collection mechanism is also fixedly mounted on the base and communicates with the output end of the microfluidic mechanism. A temperature control mechanism for adjusting the temperature of the microfluidic mechanism is also provided on the base.

Description

Technical Field

[0001] This invention relates to the field of nano-β-MnO2 preparation technology, specifically a continuous flow micro-reaction flow rate control system and preparation method for nano-β-MnO2 preparation. Background Technology

[0002] Manganese dioxide (MnO2) is an important functional material with many unique physical and chemical properties, and has been widely used in catalysis, electrochemistry, and other fields. MnO2 exists in various crystal forms, such as α, γ, β, and δ. Due to the different pore sizes and morphologies of these crystal forms, different MnO2 crystal forms exhibit significant differences in their physical and chemical properties. β-MnO2 is the most thermodynamically stable of the many MnO2 crystal forms.

[0003] In the existing technology, β-MnO2 is generally prepared by hydrothermal method, which has a long preparation cycle. Currently, microreactors can be used to catalyze it. However, existing microfluidic devices cannot change the flow rate during the reaction and can only carry out the reaction for a fixed time. Furthermore, after the reaction solution is fed into the microfluidic device, it cannot be stirred, resulting in uneven mixing of the solution and incomplete reaction.

[0004] Therefore, it is necessary to provide a continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 to solve the problems mentioned in the background art. Summary of the Invention

[0005] To achieve the above objectives, the present invention provides the following technical solution: a continuous flow microreactor flow rate control system for the preparation of nano β-MnO2, comprising a base, a first injection tube, a second injection tube, a microchannel mechanism, and a collection mechanism. The first and second injection tubes are both fixedly mounted on the base, and each contains a first reaction solution and a second reaction solution, respectively. The microchannel mechanism is fixedly mounted on the base and communicates with the first and second injection tubes. A collection mechanism is also fixedly mounted on the base and communicates with the output end of the microchannel mechanism. A temperature control mechanism for adjusting the temperature of the microchannel mechanism is also provided on the base.

[0006] Furthermore, as a preferred embodiment, the microfluidic mechanism includes a housing, an upper flow plate, a lower flow plate, and a mixing chamber. The housing has a liquid inlet 1 and a liquid inlet 2, which are respectively connected to the liquid injection pipe 1 and the liquid injection pipe 2. The liquid inlet 1 and the liquid inlet 2 merge and are connected to the mixing chamber. Multiple upper flow plates and lower flow plates are slidably and sealed in the housing.

[0007] Furthermore, the multiple upper and lower flow plates are connected end to end by telescopic plates to form a reaction channel.

[0008] Furthermore, as a preferred embodiment, the mixing chamber is S-shaped, and an arc-shaped block one and an arc-shaped block two are provided inside it, with the arc-shaped grooves of the arc-shaped block one and the arc-shaped block two being arranged opposite to each other.

[0009] Furthermore, preferably, the upper flow plate and the lower flow plate are corrugated;

[0010] The outer casing has multiple vertically formed sliding grooves. A drive rod 1 and a drive rod 2 are slidably disposed in the sliding grooves. The drive rod 1 is fixedly connected to the upper flow plate, and the drive rod 2 is fixedly connected to the lower flow plate.

[0011] Furthermore, as a preferred embodiment, the telescopic plate includes a sliding plate and a fixed plate, wherein the two ends of the sliding plate are slidably and sealed with fixed plates, and the two fixed plates are rotatably connected to the upper flow plate and the lower flow plate respectively;

[0012] The outer shell has multiple horizontally opened sliding grooves;

[0013] The slide plate is equipped with a slider that can slide along the second sealed groove.

[0014] Furthermore, as a preferred embodiment, the outer casing is also rotatably provided with multiple turntables;

[0015] The turntable has two arc-shaped grooves.

[0016] A first locking block is fixedly mounted on the first drive rod, and a second locking block is fixedly mounted on the second drive rod. The first locking block and the second locking block can slide along the arc-shaped groove.

[0017] A method for preparing nano-β-MnO2 includes the following steps:

[0018] S1. Reaction solution one and reaction solution two are injected into the microfluidic mechanism through injection tube one and injection tube two, and a uniform mixed solution is obtained through the action of the mixing chamber, and the mixed solution is filled into the reaction channel;

[0019] S2. Reaction solution one and reaction solution two are continuously injected into the reaction channel through injection tube one and injection tube two, and the temperature of the microchannel mechanism is adjusted by the temperature control mechanism so that the temperature of the reaction channel is maintained at 150-170°C.

[0020] S3. Rotate the turntable to adjust the distance between the upper flow plate and the lower flow plate, thereby changing the size of the reaction channel and changing the flow rate of the mixture in the reaction channel;

[0021] S4. Maintain the hydrothermal reaction of the solution in the reaction channel for 2-3 hours to ensure the reaction is complete;

[0022] S5. The reacted material in the reaction channel is passed into the collection mechanism, and after washing and drying, nano-β-MnO2 is obtained.

[0023] Furthermore, as a preferred embodiment, the first reaction solution is a (NH4)2S2O8 solution with a concentration of 0.10–2.00 mol / L, and the second reaction solution is a MnSO4·H2O solution with a concentration of 0.10–2.30 mol / L.

[0024] Furthermore, as a preferred embodiment, the hydrothermal reaction formula between reaction solution one and reaction solution two is as follows:

[0025] (NH4)2S2O8+MnSO4+2H2O=MnO2↓+(NH4)2SO4+2H2SO4.

[0026] Compared with the prior art, the present invention provides a continuous flow microreaction flow rate control system and preparation method for the preparation of nano β-MnO2, which has the following beneficial effects:

[0027] In this invention, a microfluidic mechanism is provided to increase the reaction rate and make the reaction conditions and temperature easier to control. The microfluidic mechanism is equipped with a mixing chamber, which, through arc-shaped blocks one and two, causes the reaction solution to form a backflow and mix evenly before being filled into the reaction channel. In addition, the reaction channel is composed of an upper flow plate and a lower flow plate, the positions of which can be adjusted to change the size of the reaction channel, thereby changing the flow rate of the solution and the reaction time of the solution in the reaction channel, making the reaction more complete. Furthermore, multiple upper flow plates and lower flow plates are connected by telescopic plates, so that the reaction channel remains in a continuous state when the size of the reaction channel changes, preventing solution leakage. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic cross-sectional view of the microchannel mechanism in this invention;

[0030] Figure 3 for Figure 2 Enlarged view of the part Figure 1 ;

[0031] Figure 4 for Figure 2 Enlarged view of the part Figure 2 ;

[0032] Figure 5 for Figure 2 Enlarged view of the part Figure 3 ;

[0033] Figure 6This is a schematic diagram of the telescopic plate implementation in this invention.

[0034] In the diagram: 1. Base; 2. Injection tube one; 3. Injection tube two; 4. Microfluidic mechanism; 41. Outer shell; 411. Inlet one; 412. Inlet two; 413. Slide 1; 414. Slide 2; 42. Upper flow plate; 43. Lower flow plate; 44. Mixing chamber; 441. Arc block one; 442. Arc block two; 45. Reaction channel; 46. Drive rod one; 461. Locking block one; 47. Drive rod two; 471. Locking block two; 48. Telescopic plate; 481. Slide plate; 482. Fixing plate; 49. Turntable; 491. Arc groove; 5. Collection mechanism; 6. Temperature control mechanism. Detailed Implementation

[0035] Example: Please refer to Figures 1-6 In this embodiment of the invention, a continuous flow microreactor flow rate control system for the preparation of nano β-MnO2 includes a base 1, a first injection tube 2, a second injection tube 3, a microfluidic mechanism 4, and a collection mechanism 5. The first injection tube 2 and the second injection tube 3 are both fixedly mounted on the base 1, and each contains a first reaction solution and a second reaction solution, respectively. The microfluidic mechanism 4 is fixedly mounted on the base 1 and communicates with the first injection tube 2 and the second injection tube 3. The collection mechanism 5 is also fixedly mounted on the base 1 and communicates with the output end of the microfluidic mechanism 4. A temperature control mechanism 6 for adjusting the temperature of the microfluidic mechanism 4 is also provided on the base 1.

[0036] In practice, reaction solution one and reaction solution two are filled into the microfluidic mechanism 4. The two-phase solutions are mixed through the mixing chamber 44 to form a mixed solution. Subsequently, the mixed solution flows along the reaction channel 45 and undergoes a hydrothermal reaction. During the reaction, the distance between the upper flow plate 42 and the lower flow plate 43 is changed by adjusting the turntable 49, thereby changing the size of the reaction channel 45. The flow rate of the mixed solution in the reaction channel 45 is adjusted according to the reaction situation to ensure that the hydrothermal reaction is complete. The reacted material is then collected by the collection mechanism 5, and the mechanism is washed and dried to obtain nano β-MnO2.

[0037] In this embodiment, as Figure 2 The microfluidic mechanism 4 includes a housing 41, an upper flow plate 42, a lower flow plate 43, and a mixing chamber 44. The housing 41 has a liquid inlet 411 and a liquid inlet 412, which are respectively connected to the liquid injection pipe 2 and the liquid injection pipe 3. The liquid inlet 411 and the liquid inlet 412 merge and are connected to the mixing chamber 44. Multiple upper flow plates 42 and lower flow plates 43 are slidably and sealed in the housing 41.

[0038] Furthermore, the multiple upper flow plates 42 and lower flow plates 43 are connected end to end by telescopic plates 48 to form a reaction channel 45.

[0039] In this embodiment, as Figure 3 The mixing chamber 44 is S-shaped, and an arc-shaped block 441 and an arc-shaped block 442 are provided inside it. The arc-shaped grooves of the arc-shaped block 441 and the arc-shaped block 442 are arranged opposite to each other.

[0040] During implementation, after reaction solution one and reaction solution two are filled into the mixing chamber 44, they can undergo a first rotation under the action of the first S-bend and the second arc block 442, and then a second rotation under the action of the first arc block 441 and the second S-bend, so that the two phase solutions are mixed evenly and the reaction is more complete.

[0041] In this embodiment, as Figure 2 , 4 The upper flow plate 42 and the lower flow plate 43 are wavy;

[0042] The outer casing 41 has a plurality of vertically formed sliding grooves 413. A drive rod 46 and a drive rod 47 are slidably disposed in the sliding grooves 413. The drive rod 46 is fixedly connected to the upper flow plate 42, and the drive rod 47 is fixedly connected to the lower flow plate 43.

[0043] In this embodiment, as Figure 4 The telescopic plate 48 includes a sliding plate 481 and a fixed plate 482, wherein the two ends of the sliding plate 481 are slidably sealed with fixed plates 482, and the two fixed plates 482 are rotatably connected to the upper flow plate 42 and the lower flow plate 43 respectively.

[0044] Multiple horizontally oriented grooves 414 are provided on the outer shell 41;

[0045] The slide plate 481 is provided with a slider, which can slide along the second slide groove 414 in a sealed manner.

[0046] Please see Figure 4 , 6When the reaction channel 45 expands, the upper flow plate 42 slides upward and the lower flow plate 43 slides downward. Both exert a pulling force on the outer fixed plate 482, causing the fixed plate 482 to slide along the slide plate 481, thus expanding its length and preventing solution leakage from the side. The upper flow plate 42 and the lower flow plate 43 exert a compressive force on the inner fixed plate 482, causing the fixed plate 482 to slide along the slide plate 481, thus reducing its length. This ensures that the reaction channel 45 remains in a sealed and connected state when it expands. During this process, the slide plate 481 slides through the second slide groove 414 to counteract the slight displacement caused by the pulling and compressive forces. Similarly, when the reaction channel 45 shrinks, the upper flow plate 42 slides downward and the lower flow plate 43 slides upward, driving the fixed plate 482 to slide, thus keeping the reaction channel 45 in a sealed and connected state.

[0047] In this embodiment, as Figure 5 The outer casing 41 is also rotatably provided with multiple turntables 49;

[0048] The turntable 49 has two arc-shaped grooves 491.

[0049] A locking block 461 is fixedly installed on the first drive rod 46, and a locking block 471 is fixedly installed on the second drive rod 47. The locking block 461 and the locking block 471 can slide along the arc groove 491.

[0050] In addition, the drive method of the turntable 49 is multifaceted. The turntables 49 can be connected in series by a chain or belt, and then driven uniformly by a motor, so that multiple upper flow plates 42 and lower flow plates 43 can expand and contract uniformly.

[0051] During implementation, the turntable 49 rotates, which can drive the first locking block 461 and the second locking block 471 to slide along the arc-shaped groove 491, and drive the first driving rod 46 and the second driving rod 47 to slide up and down. When the first driving rod 46 slides upward, the second driving rod 47 slides downward, and the two always slide relative to each other, thereby controlling the expansion and contraction of the reaction channel 45. During this process, the first sliding groove 413 can restrict the first driving rod 46 and the second driving rod 47, so that the two only slide vertically.

[0052] A method for preparing nano-β-MnO2 includes the following steps:

[0053] S1. Reaction solution one and reaction solution two are injected into the microfluidic mechanism 4 through injection tube one 2 and injection tube two 3. A uniform mixed solution is obtained through the action of the mixing chamber 44, and the mixed solution is filled into the reaction channel 45.

[0054] S2. Reaction solution one and reaction solution two are continuously injected into the reaction channel 45 through injection tube one 2 and injection tube two 3, and the temperature of the microchannel mechanism 4 is adjusted by the temperature control mechanism 6 so that the temperature of the reaction channel 45 is maintained at 150-170℃.

[0055] S3. Rotate the turntable 49 to adjust the distance between the upper flow plate 42 and the lower flow plate 43, thereby changing the size of the reaction channel 45 and changing the flow rate of the mixture in the reaction channel 45.

[0056] S4. Maintain the hydrothermal reaction of the solution in the reaction channel 45 for 2-3 hours to ensure the reaction is complete;

[0057] S5. The reacted material in the reaction channel 45 is passed into the collection mechanism 5, and after washing and drying, nano β-MnO2 is obtained.

[0058] In this embodiment, the first reaction solution is a (NH4)2S2O8 solution with a concentration of 0.10–2.00 mol / L, and the second reaction solution is a MnSO4·H2O solution with a concentration of 0.10–2.30 mol / L.

[0059] In this embodiment, the hydrothermal reaction formula between reaction solution one and reaction solution two is as follows:

[0060] (NH4)2S2O8+MnSO4+2H2O=MnO2↓+(NH4)2SO4+2H2SO4.

[0061] In summary, in the implementation of this invention, (NH4)2S2O8 solution and MnSO4·H2O solution are injected into the microfluidic mechanism 4 through injection tube 2 and injection tube 3. The two-phase solution undergoes a hydrothermal reaction in the reaction channel 45 under the control of the temperature control mechanism 6. During this process, the upper flow plate 42 and the lower flow plate 43 are controlled to slide by the turntable 49, thereby changing the size of the reaction channel 45, which changes the flow rate of the solution and further controls the reaction time of the solution, making the reaction more complete. Subsequently, the reacted material is fed into the collection mechanism 5, and after washing and drying, nano-β-MnO2 is obtained.

[0062] 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 microreaction flow rate control system for the preparation of nano-β-MnO2, characterized in that: The device includes a base (1), a first injection tube (2), a second injection tube (3), a microfluidic mechanism (4), and a collection mechanism (5). The first injection tube (2) and the second injection tube (3) are fixedly mounted on the base (1) and contain reaction solution one and reaction solution two respectively. The microfluidic mechanism (4) is fixedly mounted on the base (1) and is connected to the first injection tube (2) and the second injection tube (3). The collection mechanism (5) is also fixedly mounted on the base (1) and is connected to the output end of the microfluidic mechanism (4). The base (1) is also equipped with a temperature control mechanism (6) for adjusting the temperature of the microfluidic mechanism (4). The microchannel mechanism (4) includes a housing (41), in which a plurality of upper flow plates (42) and lower flow plates (43) are slidably and sealed. Furthermore, the multiple upper flow plates (42) and lower flow plates (43) are connected end to end by telescopic plates (48) to form a reaction channel (45); The outer shell (41) has a plurality of vertically opened sliding grooves (413), and a drive rod (46) and a drive rod (47) are slidably arranged in the sliding grooves (413). The drive rod (46) is fixedly connected to the upper flow plate (42), and the drive rod (47) is fixedly connected to the lower flow plate (43). The outer casing (41) is also rotatably provided with multiple turntables (49); The turntable (49) has two arc-shaped grooves (491); A first locking block (461) is fixedly installed on the first drive rod (46), and a second locking block (471) is fixedly installed on the second drive rod (47). The first locking block (461) and the second locking block (471) can slide along the arc groove (491).

2. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 1, characterized in that: The microfluidic mechanism (4) further includes a mixing chamber (44), wherein the outer shell (41) is provided with a liquid inlet one (411) and a liquid inlet two (412), which are respectively connected to the liquid injection pipe one (2) and the liquid injection pipe two (3). The liquid inlet one (411) and the liquid inlet two (412) merge and are connected to the mixing chamber (44).

3. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 2, characterized in that: The mixing chamber (44) is S-shaped, and an arc-shaped block one (441) and an arc-shaped block two (442) are provided inside it. The arc-shaped grooves of the arc-shaped block one (441) and the arc-shaped block two (442) are arranged opposite to each other.

4. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 2, characterized in that: The upper flow plate (42) and the lower flow plate (43) are wavy.

5. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 4, characterized in that: The telescopic plate (48) includes a sliding plate (481) and a fixed plate (482), wherein the two ends of the sliding plate (481) are sealed and slidably provided with fixed plates (482), and the two fixed plates (482) are rotatably connected to the upper flow plate (42) and the lower flow plate (43) respectively. The outer shell (41) is provided with a plurality of horizontal sliding grooves (414); The slide plate (481) is provided with a slider, which can slide along the second slide groove (414) in a sealed manner.

6. A method for preparing nano-β-MnO2, comprising employing a continuous flow microreaction flow rate control system for preparing nano-β-MnO2 as described in claim 1, characterized in that: Includes the following steps: S1. Reaction solution one and reaction solution two are injected into the microfluidic mechanism (4) through injection tube one (2) and injection tube two (3), and a uniform mixed solution is obtained through the action of the mixing chamber (44), and the mixed solution is filled into the reaction channel (45); S2. Reaction solution one and reaction solution two are continuously injected into the reaction channel (45) through injection tube one (2) and injection tube two (3), and the temperature of the microchannel mechanism (4) is adjusted by the temperature control mechanism (6) so that the temperature of the reaction channel (45) is maintained at 150-170°C; S3. Rotate the turntable (49) to adjust the distance between the upper flow plate (42) and the lower flow plate (43), thereby changing the size of the reaction channel (45) and changing the flow rate of the mixture in the reaction channel (45); S4. Maintain the hydrothermal reaction of the solution in the reaction channel (45) for 2-3 hours to ensure the reaction is complete; S5. The reacted material in the reaction channel (45) is passed into the collection mechanism (5), and after washing and drying, nano β-MnO2 is obtained.

7. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 6, characterized in that: The first reaction solution is a (NH4)2S2O8 solution with a concentration of 0.10–2.00 mol / L, and the second reaction solution is a MnSO4·H2O solution with a concentration of 0.10–2.30 mol / L.

8. The continuous flow microreaction flow rate control system for the preparation of nano-β-MnO2 according to claim 6, characterized in that: The hydrothermal reaction equation for reaction solution one and reaction solution two is as follows: (NH4)2S2O8+MnSO4+2H2O=MnO2↓+(NH4)2SO4+2H2SO4.

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