Intelligent carbon nanotube purification device and purification method thereof

Abstract

The invention belongs to the field of carbon nano tube purification, and particularly relates to an intelligent carbon nano tube purification device and a purification method thereof.The intelligent carbon nano tube purification device comprises a box body, a cavity is formed in the box body, a heating wire is arranged in the cavity, the inner wall of the box body is fixedly connected with a guide plate, the guide plate is arranged to be annular, and the bottom of the guide plate is arranged to be an annular inclined plane; according to the intelligent carbon nano tube purifying device and the purifying method thereof, the driving assembly controls the feeding hopper to move up and down in a reciprocating mode, so that the downward pressing rod moves up and down in the feeding pipe in a reciprocating mode, and through extrusion of the downward pressing rod, a carbon nano tube sample accumulated above a concentrated nitric acid solvent in the feeding pipe can be pressed downwards; when a carbon nano tube sample downwards penetrates through the feeding pipe and then upwards flows, the carbon nano tube sample can fully react with a concentrated nitric acid solvent conveniently, the downward pressing rod moving up and down in a reciprocating mode can intermittently block the feeding port, the carbon nano tube sample can be quantitatively put conveniently, and the situation that excessive carbon nano tube samples are crowded mutually and cannot react with the concentrated nitric acid solvent easily is prevented.

Description

Technical Field

[0001] The invention belongs to the field of carbon nanotube purification, and specifically relates to an intelligent carbon nanotube purification device and a purification method thereof. Background Art

[0002] Carbon nanotubes are a kind of tubular nano-scale graphite crystals. They are seamless nano-scale tubes formed by curling single or multi-layer graphite sheets around the central axis at a certain spiral angle. The C of each layer is SP2 hybridized to form a cylindrical surface of a hexagonal plane. The overall density range of carbon nanotubes is 1.2-2.1 g / cm 3 The density of single-walled carbon nanotubes is 1.2 g / cm 3 The density of multi-walled carbon nanotubes is 1.8 g / cm 3 Carbon nanotubes have a large specific surface area, light weight but super mechanical strength, excellent conductivity, good physical and chemical stability. They are a new type of material that has attracted worldwide attention. They have broad application prospects in the fields of lithium-ion battery conductive agents, catalyst carriers, drug carriers, reinforced blending materials, electronic devices, etc., but it is very difficult to obtain high-purity carbon nanotubes. Carbon nanotube purification devices usually only use physical purification methods or chemical purification methods. When purifying carbon nanotubes by chemical purification methods, the carbon nanotube samples need to be placed in concentrated nitric acid. Concentrated nitric acid will oxidize impurities such as amorphous carbon in the carbon nanotube samples into gases such as carbon dioxide, thereby improving the purity of the carbon nanotubes.

[0003] However, the density of concentrated nitric acid is generally 1.4 g / cm 3 -1.5g / cm 3 The density of single-walled carbon nanotubes is between 1.2 g / cm 3 And it has a large specific surface area and a special hollow structure, which will reduce its effective density. Therefore, after the single-walled carbon nanotubes with a density value smaller than that of concentrated nitric acid are placed in concentrated nitric acid, the single-walled carbon nanotubes will float on the surface of the concentrated nitric acid. At this time, no matter whether it is stirred or shaken, the single-walled carbon nanotubes cannot fully react with the concentrated nitric acid, and it is not convenient to control the feeding of the single-walled carbon nanotubes. After the single-walled carbon nanotubes are added at one time, the single-walled carbon nanotubes deposited at the bottom can contact the concentrated nitric acid, but the single-walled carbon nanotubes accumulated on the top are more difficult to contact with the concentrated nitric acid. In addition, in the process of purifying the carbon nanotubes, it is not easy to reduce the interference of oxygen on the carbon nanotubes. Oxygen is easy to react with the single-walled carbon nanotubes being purified, resulting in the destruction of the structure of the single-walled carbon nanotubes.

[0004] To this end, the present invention provides an intelligent carbon nanotube purification device and a purification method thereof. Summary of the invention

[0005] In order to make up for the shortcomings of the existing technology, the density of concentrated nitric acid is generally 1.4g / cm3 -1.5g / cm 3 The density of single-walled carbon nanotubes is between 1.2 g / cm 3 And it has a large specific surface area and a special hollow structure, which will reduce its effective density. Therefore, after the single-walled carbon nanotubes with a density value smaller than that of concentrated nitric acid are placed in concentrated nitric acid, the single-walled carbon nanotubes will float on the surface of the concentrated nitric acid. At this time, no matter whether it is stirred or shaken, the single-walled carbon nanotubes cannot fully react with the concentrated nitric acid, and it is not convenient to control the feeding of the single-walled carbon nanotubes. After the single-walled carbon nanotubes are added at one time, the single-walled carbon nanotubes deposited below can contact the concentrated nitric acid, but the single-walled carbon nanotubes accumulated on the top are more difficult to contact with the concentrated nitric acid. In addition, in the purification process of the carbon nanotubes, it is not convenient to reduce the interference of oxygen on the carbon nanotubes. Oxygen is easy to react with the single-walled carbon nanotubes being purified, resulting in the problem that the structure of the single-walled carbon nanotubes is destroyed. The present invention proposes an intelligent carbon nanotube purification device and a purification method thereof.

[0006] The technical solution adopted by the present invention to solve the technical problem is: an intelligent carbon nanotube purification method described in the present invention, the purification method steps are as follows: S1: Prepare the carbon nanotube sample to be purified, concentrated nitric acid, and deionized water, add the carbon nanotube sample and concentrated nitric acid into the box, and each gram of carbon nanotube corresponds to 50-100 ml of concentrated nitric acid; S2: Start the motor to control the stirring blade to rotate, so that the carbon nanotubes are fully dispersed in the concentrated nitric acid, the concentrated nitric acid in the box is heated by the heating wire, and the liquid nitrogen is controlled to be discharged to form a protective agent to reduce additional oxidation; S3: After the reaction is completed, the solvent is transferred to a suction filtration device for suction filtration, and filter paper with a suitable pore size is used to intercept the carbon nanotubes. The filter cake is washed with deionized water until the pH value of the filtrate is close to neutral. The washed carbon nanotube filter cake is transferred to a vacuum drying oven for drying until constant weight is reached to obtain preliminarily purified carbon nanotubes.

[0007] Preferably, it includes a box body, a cavity is opened inside the box body, a heating wire is arranged inside the cavity, a guide plate is fixedly connected to the inner wall of the box body, the guide plate is arranged in an annular shape and its bottom is arranged in an annular inclined surface, a plurality of feed pipes are fixedly connected to the inner wall of the guide plate at equal intervals, a feed port is opened on the outer wall of the feed pipe, a downward pressure rod is slidably connected to the inner wall of the feed pipe, a feed hopper is fixedly connected to the top of the plurality of downward pressure rods, a guide groove is opened on the top of the feed hopper, the bottom of the guide groove is arranged in an annular inclined surface, a telescopic tube is fixedly connected to the bottom of the feed hopper, the top of the telescopic tube extends to the inside of the guide groove, a connecting tube is fixedly connected to one side of the telescopic tube, the connecting tube is inclinedly installed and one end thereof is communicated with the feed port, a driving assembly is arranged at the bottom of the box body, and the driving assembly cooperates with the feed hopper and the downward pressure rod to realize reciprocating up and down movement.

[0008] Preferably, the driving assembly includes a motor, which is fixedly mounted on the bottom of the box, and the output end of the motor extends to the interior of the box and is fixedly connected to a reciprocating screw, the outer wall of the reciprocating screw is connected to a slider via a screw nut pair, the top of the slider is fixedly connected to a sleeve, the sleeve is fixedly connected to the feed hopper, the outer wall of the reciprocating screw is fixedly connected to a rotating block below the guide plate, and the outer wall of the rotating block is fixedly connected to a plurality of stirring blades at equal intervals.

[0009] Preferably, a plurality of groups of delay blocks are equidistantly fixedly connected to the bottom of the guide plate, the groups of delay blocks are cross-installed, and a side of the delay block close to the feed pipe is set as a symmetrical inclined surface.

[0010] Preferably, the top of the guide plate is fixedly connected with a plurality of annular plates in sequence from bottom to top, the top and bottom of the annular plate are both set as annular inclined surfaces, the inner wall of the annular plate is provided with an empty groove, the top and bottom of the empty groove are both set as annular inclined surfaces, the outer wall of the reciprocating screw is fixedly connected with a plurality of rotating plates in sequence from bottom to top, the top and bottom of the rotating plate are both set as annular inclined surfaces, and the outer convex surface of the rotating plate is located at the empty groove of the annular plate.

[0011] Preferably, a plurality of first blocking blocks are equidistantly fixedly connected to the top of the rotating plate, and the side of the first blocking blocks close to the empty slot is set as a symmetrical inclined surface. A plurality of second blocking blocks are equidistantly fixedly connected to the bottom of the rotating plate, and the side of the second blocking blocks away from the empty slot is set as a symmetrical inclined surface.

[0012] Preferably, a liquid collecting box is fixedly connected to the bottom of the feed hopper, the liquid collecting box is arranged in a ring shape, the outer wall of the liquid collecting box is provided with a liquid inlet, the outer wall of the liquid collecting box is provided with a plurality of liquid outlets equidistantly located below the liquid inlet, and the outer wall of the liquid collecting box is provided with a linkage unit.

[0013] Preferably, the linkage unit includes a baffle ring, which is arranged on the outer wall of the liquid collecting box and is slidably connected to the liquid collecting box, the baffle ring and the liquid outlet are located in the same horizontal plane, the outer wall of the baffle ring is fixedly connected with a second fixing ring, the outer wall of the liquid collecting box and located above the baffle ring is fixedly connected with a first fixing ring, the inner wall of the first fixing ring is equidistantly slidably connected with a plurality of sliding shafts, the bottom of the sliding shaft is fixedly connected to the second fixing ring, the top of the sliding shaft is fixedly connected to a limiting block, the outer wall of the sliding shaft is sleeved with a spring, the top of the spring is fixedly connected to the first fixing ring, the bottom of the spring is fixedly connected to the second fixing ring, the limiting ring is fixedly connected between the plurality of telescopic tubes, and the limiting ring is used in conjunction with the second fixing ring.

[0014] Preferably, the bottom of the limiting ring is fixedly connected to a mounting ring, the top of the mounting ring is provided with an annular groove, the bottom of the annular groove is set as an annular inclined surface, the bottom of the mounting ring is fixedly connected to a gas gathering ring, and the annular plate located at the top is fixedly connected to the gas gathering ring.

[0015] Preferably, a lower pressing plate is fixedly connected to the bottom of the liquid collecting box, and an outer wall of the lower pressing plate is configured as an annular inclined surface.

[0016] The beneficial effects of the present invention are as follows: 1. The intelligent carbon nanotube purification device and purification method described in the present invention controls the feed hopper to move back and forth up and down through a driving component to make the lower pressure rod move back and forth up and down in the feed pipe. The carbon nanotube samples accumulated above the concentrated nitric acid solvent in the feed pipe can be pressed downward by the squeezing of the lower pressure rod. After the carbon nanotube samples pass downward through the feed pipe, they flow upward under the action of their own buoyancy, thereby facilitating a full reaction with the concentrated nitric acid solvent. The lower pressure rod that moves back and forth up and down can intermittently block the feed port, facilitating the quantitative addition of the carbon nanotube samples and preventing too many carbon nanotube samples from crowding each other and being difficult to react with the concentrated nitric acid solvent. In addition, the carbon nanotube samples are blocked by the guide plate so that they need to flow upward along the bottom of the guide plate, thereby prolonging the residence time of the carbon nanotube samples in the concentrated nitric acid solvent and preventing the carbon nanotube samples from floating up too quickly.

[0017] 2. The intelligent carbon nanotube purification device and purification method described in the present invention enable the carbon nanotube sample to float upward continuously through the guidance of the bottom slope of the annular plate and the bottom slope of the rotating plate, and the floating speed of the carbon nanotube sample is slowed down through the layers of obstruction of the annular plate and the rotating plate, so that the carbon nanotube sample can continue to react in the concentrated nitric acid solvent.

[0018] 3. The intelligent carbon nanotube purification device and purification method described in the present invention, when the carbon nanotube sample passes through the bottom of the rotating plate, as the second barrier block rotates, its inclined surface pushes downward the carbon nanotube sample floating upward, so that the carbon nanotube sample floats upward and then flows downward again; when the carbon nanotube sample passes through the top of the rotating plate, as the first barrier block rotates, its inclined surface pushes downward again the carbon nanotube sample floating upward, thereby extending the residence time of the carbon nanotube sample between the annular plate and the rotating plate through the cooperation of the first barrier block and the second barrier block.

[0019] 4. The intelligent carbon nanotube purification device and purification method described in the present invention can release part of the liquid nitrogen every time the liquid collecting box moves downward through the interlocking unit. After the liquid nitrogen is gasified into nitrogen, it flows to the center of the concentrated nitric acid liquid surface under the guidance of the inclined surface of the annular groove, and is wrapped by the gas gathering ring to prevent the nitrogen from diffusing rapidly, thereby further protecting the carbon nanotube sample. The carbon nanotube sample floating in the concentrated nitric acid solvent can be wrapped by the gas gathering ring, so that the carbon nanotube sample is concentrated after floating, which is convenient for material collection.

[0020] 5. The intelligent carbon nanotube purification device and purification method described in the present invention drives the lower pressure plate to move reciprocally up and down by the liquid collecting box that moves up and down, pressing down the carbon nanotube samples floating on the concentrated nitric acid liquid surface, so that the carbon nanotube samples can continue to react with the concentrated nitric acid after floating up, and by setting the outer wall of the lower pressure plate as a ring-shaped inclined surface, it is convenient for the vaporized nitrogen to flow to the center of the concentrated nitric acid liquid surface, and the effect of dispersing the oxygen above the concentrated nitric acid liquid surface is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] Figure 1 is a stereogram of the present invention; Figure 2 is a cross-sectional view of the present invention; Figure 3 It is an exploded view of the annular plate and the rotating plate of the present invention in cooperation with each other; Figure 4 It is a three-dimensional diagram of the rotating plate of the present invention used in conjunction with the first blocking block; Figure 5 It is a three-dimensional diagram of the rotating plate of the present invention and the second blocking block in cooperation with each other; Figure 6 It is a stereoscopic diagram of the guide plate and the delay block of the present invention in cooperation with each other; Figure 7 It is a three-dimensional diagram of the annular plate and the gas gathering ring of the present invention in cooperation with each other; Figure 8 The present invention Figure 2The enlarged view of point A in the middle; Fig. 9 The present invention Figure 2 Enlarged view of point B in the middle.

[0023] In the figure: 1. box body; 2. motor; 3. cavity; 4. heating wire; 5. reciprocating screw rod; 6. slider; 7. sleeve; 8. feed hopper; 9. guide groove; 10. guide plate; 11. feed pipe; 12. lower pressure rod; 13. feed port; 14. telescopic tube; 15. connecting pipe; 16. annular plate; 17. rotating plate; 18. first baffle block; 19. second baffle block; 20. rotating block; 21. stirring blade; 22. delay block; 23. liquid collecting box; 24. liquid inlet; 25. liquid outlet; 26. retaining ring; 27. first fixed ring; 28. sliding shaft; 29. ​​limit block; 30. spring; 31. second fixed ring; 32. lower pressure plate; 33. limit ring; 34. mounting ring; 35. annular groove; 36. gas gathering ring. DETAILED DESCRIPTION

[0024] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0025] like Figures 1 to 9 As shown, the present invention provides a technical solution, a smart carbon nanotube purification method, the purification method steps are as follows: S1: Prepare the carbon nanotube sample to be purified, concentrated nitric acid, and deionized water, add the carbon nanotube sample and concentrated nitric acid into the box 1, and each gram of carbon nanotube corresponds to 50-100 ml of concentrated nitric acid; S2: starting the motor 2 to control the stirring blade 21 to rotate, so that the carbon nanotubes are fully dispersed in the concentrated nitric acid, the concentrated nitric acid in the box 1 is heated by the heating wire 4, and the liquid nitrogen is controlled to be discharged to form a protective agent to reduce additional oxidation; S3: After the reaction is completed, the solvent is transferred to a suction filtration device for suction filtration, and filter paper with a suitable pore size is used to intercept the carbon nanotubes. The filter cake is washed with deionized water until the pH value of the filtrate is close to neutral. The washed carbon nanotube filter cake is transferred to a vacuum drying oven for drying until constant weight is reached to obtain preliminarily purified carbon nanotubes.

[0026] Specifically, it includes a box body 1, a cavity 3 is opened inside the box body 1, a heating wire 4 is arranged inside the cavity 3, a guide plate 10 is fixedly connected to the inner wall of the box body 1, the guide plate 10 is arranged in a ring shape and its bottom is arranged in a ring shape, a plurality of feed pipes 11 are fixedly connected to the inner wall of the guide plate 10 at equal intervals, a feed port 13 is opened on the outer wall of the feed pipe 11, a lower pressure rod 12 is slidably connected to the inner wall of the feed pipe 11, a feed hopper 8 is fixedly connected to the top of the plurality of lower pressure rods 12, a guide groove 9 is opened on the top of the feed hopper 8, the bottom of the guide groove 9 is arranged in a ring shape, a telescopic tube 14 is fixedly connected to the bottom of the feed hopper 8, the top of the telescopic tube 14 extends to the inside of the guide groove 9, a connecting tube 15 is fixedly connected to one side of the telescopic tube 14, the connecting tube 15 is inclinedly installed and one end thereof is communicated with the feed port 13, a driving assembly is arranged at the bottom of the box body 1, the driving assembly cooperates with the feed hopper 8 and the lower pressure rod 12 to realize reciprocating up and down motion.

[0027] Through the above technical solution, concentrated nitric acid solvent is injected into the box body 1, the liquid level of the concentrated nitric acid solvent is located at the inclined surface of the feed port 13, the heating wire 4 is started to heat the concentrated nitric acid solvent, and the carbon nanotube sample is placed in the feed hopper 8. The carbon nanotube sample enters the telescopic tube 14 along the guide groove 9, and passes through the connecting tube 15 and the feed port 13 to enter the feed pipe 11. The feed hopper 8 is controlled to move up and down reciprocatingly by the driving component. When the feed hopper 8 moves downward, the pressing rod 12 is driven to slide in the feed pipe 11. At this time, the feed port 13 is blocked to prevent the carbon nanotube sample from continuing to be discharged. The carbon nanotube sample accumulated above the concentrated nitric acid solvent in the feed pipe 11 is squeezed by the pressing rod 12. The carbon nanotube sample is pressed downward, and after the carbon nanotube sample passes downward through the feed tube 11, it flows upward under the action of its own buoyancy, thereby facilitating a full reaction with the concentrated nitric acid solvent. When the feed hopper 8 moves upward, the obstruction of the downward pressure rod 12 is lost, and the carbon nanotube sample can be fed into the feed tube 11 again. This reciprocating process facilitates the quantitative addition of the carbon nanotube sample and prevents too many carbon nanotube samples from crowding each other and being difficult to react with the concentrated nitric acid solvent. The carbon nanotube sample is blocked by the guide plate 10 so that it needs to flow upward along the bottom of the guide plate 10, thereby extending the residence time of the carbon nanotube sample in the concentrated nitric acid solvent and preventing the carbon nanotube sample from floating up too quickly.

[0028] Specifically, the driving assembly includes a motor 2, which is fixedly installed at the bottom of the box body 1. The output end of the motor 2 extends to the interior of the box body 1 and is fixedly connected to a reciprocating screw 5. The outer wall of the reciprocating screw 5 is connected to a slider 6 through a screw nut pair. The top of the slider 6 is fixedly connected to a sleeve 7. The sleeve 7 is fixedly connected to a feed hopper 8. The outer wall of the reciprocating screw 5 is fixedly connected to a rotating block 20 located below the guide plate 10, and the outer wall of the rotating block 20 is fixedly connected to a plurality of stirring blades 21 at equal intervals.

[0029] Through the above technical solution, the motor 2 is started to drive the reciprocating screw 5 to rotate, so that the slider 6 moves back and forth up and down, drives the sleeve 7 to move back and forth up and down, and makes the feed hopper 8 move back and forth up and down. While the reciprocating screw 5 rotates, it drives several stirring blades 21 to rotate, stirs the carbon nanotube sample in the concentrated nitric acid solvent, and allows the carbon nanotube sample to fully react.

[0030] Specifically, a plurality of groups of delay blocks 22 are fixedly connected to the bottom of the guide plate 10 at equal intervals. The plurality of groups of delay blocks 22 are cross-installed, and a side of the delay block 22 close to the feed pipe 11 is set as a symmetrical inclined surface.

[0031] Through the above technical solution, when the carbon nanotube sample passes downward through the feed tube 11 and floats upward along the inclined surface at the bottom of the guide plate 10, the carbon nanotube sample floating upward is blocked by setting a cross-mounted delay block 22, thereby further extending the immersion time of the carbon nanotube sample in the concentrated nitric acid solvent, and by setting one side of the delay block 22 as a symmetrical inclined surface, the carbon nanotube sample is prevented from being stuck at the bottom of the delay block 22 and unable to be retrieved.

[0032] Specifically, the top of the guide plate 10 is fixedly connected with a plurality of annular plates 16 in sequence from bottom to top, the top and bottom of the annular plate 16 are both set as annular inclined surfaces, the inner wall of the annular plate 16 is provided with an empty groove, the top and bottom of the empty groove are both set as annular inclined surfaces, and the outer wall of the reciprocating screw rod 5 is fixedly connected with a plurality of rotating plates 17 in sequence from bottom to top, the top and bottom of the rotating plate 17 are both set as annular inclined surfaces, and the outer convex surface of the rotating plate 17 is located at the empty groove of the annular plate 16.

[0033] Through the above technical solution, after the carbon nanotube sample passes through the guide plate 10, it enters the gap between the plurality of annular plates 16 and the plurality of rotating plates 17, and is guided by the bottom inclined surface of the annular plate 16 and the bottom inclined surface of the rotating plate 17, so that the carbon nanotube sample can continue to float upward, and is obstructed by the layers of annular plates 16 and rotating plates 17, so that the floating speed of the carbon nanotube sample is slowed down, so that the carbon nanotube sample can continue to react in the concentrated nitric acid solvent.

[0034] Specifically, a plurality of first blocking blocks 18 are equidistantly fixedly connected to the top of the rotating plate 17, and the side of the first blocking block 18 close to the empty slot is set as a symmetrical inclined surface. A plurality of second blocking blocks 19 are equidistantly fixedly connected to the bottom of the rotating plate 17, and the side of the second blocking block 19 away from the empty slot is set as a symmetrical inclined surface.

[0035] Through the above technical solution, the reciprocating screw 5 rotates while driving the rotating plate 17 to rotate, so that the first barrier block 18 and the second barrier block 19 rotate. When the carbon nanotube sample passes through the bottom of the rotating plate 17, as the second barrier block 19 rotates, its inclined surface pushes the carbon nanotube sample floating upward downward, so that the carbon nanotube sample floats upward and then flows downward again. When the carbon nanotube sample passes through the top of the rotating plate 17, as the first barrier block 18 rotates, its inclined surface pushes the carbon nanotube sample floating upward downward again. Therefore, through the cooperation of the first barrier block 18 and the second barrier block 19, the residence time of the carbon nanotube sample between the annular plate 16 and the rotating plate 17 is extended.

[0036] Specifically, a liquid collecting box 23 is fixedly connected to the bottom of the feed hopper 8. The liquid collecting box 23 is arranged in a ring shape. The outer wall of the liquid collecting box 23 is provided with a liquid inlet 24. The outer wall of the liquid collecting box 23 is evenly spaced below the liquid inlet 24 and a plurality of liquid outlets 25 are provided. The outer wall of the liquid collecting box 23 is provided with a linkage unit.

[0037] Through the above technical solution, liquid nitrogen is charged into the liquid collecting box 23 through the liquid inlet 24, and the feed hopper 8 reciprocates up and down while driving the liquid collecting box 23 to move reciprocate up and down. Through the provided linkage unit, when the liquid collecting box 23 moves downward and approaches the liquid surface of concentrated nitric acid, a part of the liquid nitrogen is released. After being released to the outside, the liquid nitrogen is rapidly vaporized into nitrogen gas, thereby dispersing the oxygen near the liquid surface of concentrated nitric acid, preventing oxygen from reacting with the carbon nanotube sample, and reducing the damage of oxygen to the carbon nanotube sample.

[0038] Specifically, the linkage unit includes a baffle ring 26, which is arranged on the outer wall of the liquid collecting box 23 and is slidably connected to the liquid collecting box 23. The baffle ring 26 and the liquid outlet 25 are located in the same horizontal plane. The outer wall of the baffle ring 26 is fixedly connected with a second fixed ring 31, and the outer wall of the liquid collecting box 23 and located above the baffle ring 26 are fixedly connected with a first fixed ring 27. The inner wall of the first fixed ring 27 is equidistantly slidably connected with a plurality of sliding shafts 28. The bottom of the sliding shaft 28 is fixedly connected to the second fixed ring 31, and the top of the sliding shaft 28 is fixedly connected to a limiting block 29. The outer wall of the sliding shaft 28 is sleeved with a spring 30, and the top of the spring 30 is fixedly connected to the first fixed ring 27, and the bottom of the spring 30 is fixedly connected to the second fixed ring 31. A limiting ring 33 is fixedly connected between a plurality of telescopic tubes 14, and the limiting ring 33 is used in conjunction with the second fixed ring 31.

[0039] Through the above technical solution, the spring 30 is set to make the baffle ring 26 block the liquid outlet 25 to prevent liquid nitrogen from leaking from the liquid outlet 25. When the feed hopper 8 moves downward, it drives the liquid collecting box 23 to move downward, so that the second fixed ring 31 moves downward. When the second fixed ring 31 moves to the limit ring 33, the second fixed ring 31 cannot move due to the obstruction of the limit ring 33. At this time, as the liquid collecting box 23 continues to move downward, the baffle ring 26 slides on the outer wall of the liquid collecting box 23, and loses the obstruction to several liquid outlets 25. The liquid nitrogen drips outward along the several liquid outlets 25. When the liquid nitrogen is gasified into nitrogen, it is evenly distributed above the concentrated nitric acid liquid surface to protect the carbon nanotube sample. When the liquid collecting box 23 moves upward, under the action of the spring 30, the baffle ring 26 is reset to block the liquid outlet 25 again.

[0040] Specifically, the bottom of the limiting ring 33 is fixedly connected to a mounting ring 34, the top of the mounting ring 34 is provided with an annular groove 35, the bottom of the annular groove 35 is set as an annular inclined surface, the bottom of the mounting ring 34 is fixedly connected to a gas gathering ring 36, and the annular plate 16 located at the top is fixedly connected to the gas gathering ring 36.

[0041] Through the above technical solution, after the liquid nitrogen is vaporized into nitrogen, it flows to the center of the concentrated nitric acid liquid surface under the guidance of the inclined surface of the annular groove 35, and the nitrogen is wrapped by the set gas gathering ring 36 to prevent the nitrogen from rapidly diffusing, thereby further protecting the carbon nanotube sample. In addition, the set gas gathering ring 36 can wrap the carbon nanotube sample floating in the concentrated nitric acid solvent, so that the carbon nanotube sample is concentrated after floating, which is convenient for material collection.

[0042] Specifically, a lower pressing plate 32 is fixedly connected to the bottom of the liquid collecting box 23, and an outer wall of the lower pressing plate 32 is configured as an annular inclined surface.

[0043] Through the above technical solution, the liquid collecting box 23 moves back and forth up and down, while driving the lower pressure plate 32 to move back and forth up and down. When the lower pressure plate 32 moves downward, the carbon nanotube sample floating on the surface of the concentrated nitric acid liquid is pressed downward, so that the carbon nanotube sample can continue to react with the concentrated nitric acid after floating up, and by setting the outer wall of the lower pressure plate 32 as a circular inclined surface, the vaporized nitrogen is facilitated to flow to the center of the concentrated nitric acid liquid surface, and the effect of dispersing the oxygen above the concentrated nitric acid liquid surface is better.

[0044] When in use, a concentrated nitric acid solvent is injected into the housing 1, the liquid level of the concentrated nitric acid solvent is located at the inclined surface of the feed port 13, the heating wire 4 is started to heat the concentrated nitric acid solvent, the carbon nanotube sample is put into the feed hopper 8, the carbon nanotube sample enters the telescopic tube 14 along the guide groove 9, and passes through the connecting tube 15 and the feed port 13 to enter the feed pipe 11, the motor 2 is started to drive the reciprocating screw rod 5 to rotate, the slider 6 moves up and down reciprocatingly, the sleeve 7 moves up and down reciprocatingly, and the feed hopper 8 moves up and down reciprocatingly. When the reciprocating screw rod 5 rotates, it drives a plurality of stirring blades 21 to rotate, stirs the carbon nanotube sample in the concentrated nitric acid solvent, and enables the carbon nanotube sample to fully react. When the feed hopper 8 moves downward, it drives the lower pressure rod 12 to slide in the feed pipe 11, and through the lower pressure rod 12, the lower pressure rod 12 is driven to slide in the feed pipe 11. The pressing rod 12 is squeezed to press the carbon nanotube sample accumulated above the concentrated nitric acid solvent in the feed tube 11 downward. After the carbon nanotube sample passes through the feed tube 11 downward, it flows upward under the action of its own buoyancy, thereby facilitating a full reaction with the concentrated nitric acid solvent. When the feed hopper 8 moves upward, the obstruction of the pressing rod 12 is lost, and the carbon nanotube sample can be fed into the feed tube 11 again. This reciprocating motion facilitates the quantitative addition of the carbon nanotube sample and prevents too many carbon nanotube samples from crowding each other and being difficult to react with the concentrated nitric acid solvent. The carbon nanotube sample is blocked by the guide plate 10 so that it needs to flow upward along the bottom of the guide plate 10, thereby extending the residence time of the carbon nanotube sample in the concentrated nitric acid solvent and preventing the carbon nanotube sample from floating up too quickly. When the carbon nanotube When the sample passes downward through the feed tube 11 and floats upward along the inclined surface at the bottom of the guide plate 10, the carbon nanotube sample floating upward is blocked by setting a cross-installed delay block 22 to further extend the immersion time of the carbon nanotube sample in the concentrated nitric acid solvent. By setting one side of the delay block 22 as a symmetrical inclined surface, the carbon nanotube sample is prevented from being stuck at the bottom of the delay block 22 and unable to be taken out. After the carbon nanotube sample passes through the guide plate 10, it enters the gap between the plurality of annular plates 16 and the plurality of rotating plates 17. The carbon nanotube sample is guided by the inclined surface at the bottom of the annular plate 16 and the inclined surface at the bottom of the rotating plate 17, so that the carbon nanotube sample can continue to float upward, and the floating speed of the carbon nanotube sample is delayed through the layers of obstruction of the annular plate 16 and the rotating plate 17, so that the carbon nanotube sample The product can continuously react in the concentrated nitric acid solvent. The reciprocating screw 5 rotates while driving the rotating plate 17 to rotate the first barrier block 18 and the second barrier block 19. When the carbon nanotube sample passes through the bottom of the rotating plate 17, as the second barrier block 19 rotates, its inclined surface pushes downward the carbon nanotube sample that floats upward, so that the carbon nanotube sample floats upward and then flows downward again. When the carbon nanotube sample passes through the top of the rotating plate 17, as the first barrier block 18 rotates, its inclined surface pushes downward again the carbon nanotube sample that floats upward. Thus, through the cooperation of the first barrier block 18 and the second barrier block 19, the residence time of the carbon nanotube sample between the annular plate 16 and the rotating plate 17 is extended. Liquid nitrogen is filled into the liquid collecting box 23 through the liquid inlet 24.The feed hopper 8 reciprocates up and down while driving the liquid collecting box 23 to move up and down. The spring 30 is provided to make the baffle ring 26 block the liquid outlet 25 to prevent liquid nitrogen from leaking out of the liquid outlet 25. When the feed hopper 8 moves downward, it drives the liquid collecting box 23 to move downward, causing the second fixing ring 31 to move downward. When the second fixing ring 31 moves to the limit ring 33, the second fixing ring 31 cannot move due to the blockage of the limit ring 33. At this time, as the liquid collecting box 23 continues to move downward, the baffle ring 26 slides on the outer wall of the liquid collecting box 23, losing the blockage of several liquid outlets 25, and the liquid nitrogen drips outward along the several liquid outlets 25. When the liquid nitrogen is gasified into nitrogen, it is evenly distributed above the concentrated nitric acid liquid surface to protect the carbon nanotube sample. When the liquid nitrogen moves upward, the spring 30 causes the retaining ring 26 to reset and block the liquid outlet 25 again. After the liquid nitrogen is gasified into nitrogen, it flows to the center of the concentrated nitric acid liquid surface under the guidance of the inclined surface of the annular groove 35, and the nitrogen is wrapped by the gas gathering ring 36 to prevent the nitrogen from rapidly diffusing, thereby further protecting the carbon nanotube sample. The gas gathering ring 36 can wrap the carbon nanotube sample floating in the concentrated nitric acid solvent, so that the carbon nanotube sample is concentrated after floating, which is convenient for material collection. The liquid collecting box 23 reciprocates up and down while driving the lower pressing plate 32 to reciprocate up and down. When the lower pressing plate 32 moves downward, the carbon nanotube sample floating on the concentrated nitric acid liquid surface is pressed downward, so that the carbon nanotube sample can continue to react with the concentrated nitric acid after floating.

[0045] The above-mentioned front, back, left, right, top and bottom are all based on the figures in the specification. Figure 1 As a benchmark, according to the person's observation perspective, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0047] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An intelligent carbon nanotube purification device, characterized in that: The invention comprises a box body (1), wherein a cavity (3) is provided inside the box body (1), a heating wire (4) is provided inside the cavity (3), a guide plate (10) is fixedly connected to the inner wall of the box body (1), the guide plate (10) is arranged in an annular shape and its bottom is arranged in an annular inclined surface, a plurality of feed pipes (11) are fixedly connected to the inner wall of the guide plate (10) at equal intervals, a feed port (13) is provided on the outer wall of the feed pipe (11), a downward pressing rod (12) is slidably connected to the inner wall of the feed pipe (11), and a plurality of feed hoppers are fixedly connected to the tops of the downward pressing rods (12) (8), a guide groove (9) is provided at the top of the feed hopper (8), the bottom of the guide groove (9) is arranged as an annular inclined surface, a telescopic tube (14) is fixedly connected to the bottom of the feed hopper (8), the top of the telescopic tube (14) extends to the inside of the guide groove (9), a connecting tube (15) is fixedly connected to one side of the telescopic tube (14), the connecting tube (15) is installed at an angle and one end thereof is connected to the feed port (13), a driving assembly is arranged at the bottom of the box body (1), and the driving assembly cooperates with the feed hopper (8) and the lower pressure rod (12) to realize reciprocating up and down motion.

2. The intelligent carbon nanotube purification device according to claim 1, characterized in that: The drive assembly comprises a motor (2), the motor (2) being fixedly mounted at the bottom of the housing (1), the output end of the motor (2) extending into the interior of the housing (1) and being fixedly connected to a reciprocating screw (5), the outer wall of the reciprocating screw (5) being connected to a slider (6) via a screw nut pair, the top of the slider (6) being fixedly connected to a sleeve (7), the sleeve (7) being fixedly connected to a feed hopper (8), the outer wall of the reciprocating screw (5) being fixedly connected to a rotating block (20) located below the guide plate (10), the outer wall of the rotating block (20) being fixedly connected to a plurality of stirring blades (21) at equal intervals.

3. The intelligent carbon nanotube purification device according to claim 2, characterized in that: A plurality of groups of delay blocks (22) are fixedly connected to the bottom of the guide plate (10) at equal intervals. The plurality of groups of delay blocks (22) are cross-mounted, and a side of the delay block (22) close to the feed pipe (11) is arranged as a symmetrical inclined surface.

4. The intelligent carbon nanotube purification device according to claim 3, characterized in that: A plurality of annular plates (16) are fixedly connected to the top of the guide plate (10) in sequence from bottom to top, the top and bottom of the annular plate (16) are both arranged as annular inclined surfaces, an inner wall of the annular plate (16) is provided with a hollow groove, the top and bottom of the hollow groove are both arranged as annular inclined surfaces, and an outer wall of the reciprocating screw rod (5) is fixedly connected to a plurality of rotating plates (17) in sequence from bottom to top, the top and bottom of the rotating plate (17) are both arranged as annular inclined surfaces, and the outer convex surface of the rotating plate (17) is located at the hollow groove of the annular plate (16).

5. The intelligent carbon nanotube purification device according to claim 4, characterized in that: A plurality of first blocking blocks (18) are fixedly connected at equal intervals to the top of the rotating plate (17), and a side of the first blocking block (18) close to the empty slot is arranged as a symmetrical inclined surface. A plurality of second blocking blocks (19) are fixedly connected at equal intervals to the bottom of the rotating plate (17), and a side of the second blocking block (19) away from the empty slot is arranged as a symmetrical inclined surface.

6. The intelligent carbon nanotube purification device according to claim 5, characterized in that: A liquid collecting box (23) is fixedly connected to the bottom of the feed hopper (8); the liquid collecting box (23) is arranged in a ring shape; an outer wall of the liquid collecting box (23) is provided with a liquid inlet (24); a plurality of liquid outlets (25) are equidistantly provided on the outer wall of the liquid collecting box (23) and below the liquid inlet (24); and a linkage unit is provided on the outer wall of the liquid collecting box (23).

7. The intelligent carbon nanotube purification device according to claim 6, characterized in that: The linkage unit comprises a retaining ring (26), the retaining ring (26) being arranged on the outer wall of the liquid collecting box (23) and being slidably connected to the liquid collecting box (23), the retaining ring (26) and the liquid outlet (25) being located on the same horizontal plane, the outer wall of the retaining ring (26) being fixedly connected to a second fixing ring (31), the outer wall of the liquid collecting box (23) being fixedly connected to a first fixing ring (27) located above the retaining ring (26), the inner wall of the first fixing ring (27) being slidably connected to a plurality of sliding shafts (28) at equal intervals, The bottom of the sliding shaft (28) is fixedly connected to the second fixing ring (31), the top of the sliding shaft (28) is fixedly connected to a limiting block (29), the outer wall of the sliding shaft (28) is sleeved with a spring (30), the top of the spring (30) is fixedly connected to the first fixing ring (27), the bottom of the spring (30) is fixedly connected to the second fixing ring (31), and a limiting ring (33) is fixedly connected between a plurality of the telescopic tubes (14), and the limiting ring (33) is used in conjunction with the second fixing ring (31).

8. The intelligent carbon nanotube purification device according to claim 7, characterized in that: The bottom of the limiting ring (33) is fixedly connected to a mounting ring (34), the top of the mounting ring (34) is provided with an annular groove (35), the bottom of the annular groove (35) is arranged as an annular inclined surface, the bottom of the mounting ring (34) is fixedly connected to a gas gathering ring (36), and the annular plate (16) located at the top is fixedly connected to the gas gathering ring (36).

9. The intelligent carbon nanotube purification device according to claim 8, characterized in that: A lower pressing plate (32) is fixedly connected to the bottom of the liquid collecting box (23), and the outer wall of the lower pressing plate (32) is arranged as an annular inclined surface.

10. An intelligent carbon nanotube purification method, wherein the device used in the purification method is an intelligent carbon nanotube purification device according to any one of claims 1 to 9, characterized in that: The purification method steps are as follows: S1: preparing a carbon nanotube sample to be purified, concentrated nitric acid, and deionized water, and adding the carbon nanotube sample and concentrated nitric acid into a box (1), wherein each gram of carbon nanotube corresponds to 50-100 ml of concentrated nitric acid; S2: starting the motor (2) to control the stirring blade (21) to rotate, so that the carbon nanotubes are fully dispersed in the concentrated nitric acid, heating the concentrated nitric acid in the box (1) through the heating wire (4), and controlling the discharge of liquid nitrogen to form a protective agent to reduce additional oxidation; S3: After the reaction is completed, the solvent is transferred to a suction filtration device for suction filtration, and filter paper with a suitable pore size is used to intercept the carbon nanotubes. The filter cake is washed with deionized water until the pH value of the filtrate is close to neutral. The washed carbon nanotube filter cake is transferred to a vacuum drying oven for drying until constant weight is reached to obtain preliminarily purified carbon nanotubes.

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