A single-walled carbon nanotube collecting device

Abstract

This invention discloses a single-walled carbon nanotube collecting device, relating to the technical field of carbon nanotube preparation. It is used to collect single-walled carbon nanotubes entering the deposition zone of a tubular reactor. The device includes a collecting net arranged within the deposition zone, a sealing flange near the deposition zone connected to the end of the tubular reactor by a screw connection, the collecting net mounted on the sealing flange, and a sealing ring installed at the axial end of the sealing flange. A first contact surface is provided inside the tubular reactor. During the stroke of inserting the sealing flange into the tubular reactor and rotating it, the end of the sealing flange, in conjunction with the first contact surface, compresses the sealing ring, causing elastic deformation. The elastically deformed sealing ring then comes into contact with the collecting net.

Description

Technical Field

[0001] This invention relates to the technical field of carbon nanotube preparation, specifically a single-walled carbon nanotube collection device. Background Technology

[0002] As is generally known, carbon nanotubes are seamless tubes formed by coiling one or more layers of graphite sheets around a central axis at a certain helical angle. They can be classified into single-walled and multi-walled carbon nanotubes based on the number of carbon atom layers. Single-walled carbon nanotubes can be prepared using inductively coupled plasma (ICP) technology.

[0003] The steps for preparing single-walled carbon nanotubes using inductively coupled plasma (ICP) technology are as follows: The catalyst is placed in a tank in a catalyst preparation apparatus and heated and vaporized (temperature 1500~3000℃); the vaporized catalyst is carried into a tubular reactor by a carrier gas (N2, Ar), and the temperature of the tubular reactor is set to (650~1300℃); hydrocarbon gas is introduced at the inlet of the tubular reactor as a carbon source; then, single-walled carbon nanotubes are formed and deposited in the tubular reactor.

[0004] The tubular reactor has a horizontally placed cylindrical structure, with a main body made of transparent quartz (allowing observation of the internal reaction). It is 120cm long and 6cm in diameter, with sealed flanges at both ends (for connecting the gas inlet and outlet pipes and the catalyst carrier gas inlet). Along its length, the interior of the tubular reactor is divided into three zones:

[0005] The pyrolysis zone is located at the left end and is about 30-40cm long (accounting for 1 / 4 to 1 / 3 of the total length). It is wrapped with the first heating module (such as a resistance heating sleeve, which is a ring-shaped quartz tube wrapped with red color to indicate the high temperature area). The flange at the left end connects the "carrier gas and catalyst mixing inlet" and the "hydrocarbon gas inlet". The two gases meet in this area and complete the carbon source pyrolysis.

[0006] Synthesis Zone: Located in the middle, about 40-50cm in length (accounting for 1 / 3 to 2 / 5 of the total length), it is the core area of ​​the tubular reactor. It is surrounded by a second set of heating modules (with the highest heating power, set in dark red to indicate the highest temperature area). In this area, the gaseous catalyst and active carbon atoms react fully to generate single-walled carbon nanotubes. Slight black substances can be observed on the inner wall of the quartz tube (initial signs of carbon nanotube growth).

[0007] Deposition zone: Located at the right end, approximately 30-40cm in length (similar to the length of the pyrolysis zone), it is surrounded by a third heating module (with the lowest heating power, colored orange to indicate the medium temperature zone). The right-end flange connects to the exhaust gas output pipe. Black single-walled carbon nanotubes are deposited in this area on the inner wall of the quartz tube or on a special collection net (which needs to be placed in the deposition zone in advance) for easy removal later.

[0008] The shortcoming of the existing technology is that, due to installation errors and insufficient material rigidity, there is a gap between the collection net and the inner wall of the tubular reactor. The airflow carrying catalyst particles and carbon nanotubes may leak through the gap, which will cause pollution to the downstream pipeline of the tubular reactor and increase the cleaning cost. Summary of the Invention

[0009] The purpose of this invention is to provide a single-walled carbon nanotube collection device to solve the technical problems in related technologies. To achieve the above objective, this invention provides the following technical solution:

[0010] A single-walled carbon nanotube (SCH) collection device is provided for collecting SCHs entering the deposition zone of a tubular reactor. The device includes a collection net arranged within the deposition zone, a sealing flange near the deposition zone connected to the end of the tubular reactor via a screw connection, the collection net mounted on the sealing flange, and a sealing ring installed at the axial end of the sealing flange. A first contact surface is provided inside the tubular reactor. During the insertion and rotation of the sealing flange into the tubular reactor, the end of the sealing flange, in conjunction with the first contact surface, compresses the sealing ring, causing elastic deformation. The elastically deformed sealing ring then comes into contact with the collection net.

[0011] As described above, the sealing ring has an isosceles trapezoidal cross-section, with its upper base connected to the end of the sealing flange and its lower base abutting against the first contact surface.

[0012] As described above, a first ring body is installed on the sealing flange, a support layer mesh is installed on the first ring body, a second ring body is installed in the cone bottom area of ​​the collecting mesh, the second ring body is slidably sleeved on the first ring body, and the sealing ring that undergoes elastic deformation abuts against the second ring body.

[0013] As described above, the support layer mesh has a conical structure, with the cone apex facing away from the sealing flange, and the shape of the collection mesh is adapted to the shape of the support layer mesh.

[0014] As mentioned above, the mesh size of the top region of the collecting net is smaller than that of the body region, and the mesh size of the body region is smaller than that of the bottom region.

[0015] As described above, a filter screen is arranged on the side of the collecting net away from the supporting layer net. The filter screen is used to collect catalyst particles. The shape of the filter screen is adapted to the shape of the collecting net. A third ring body is installed in the cone bottom area of ​​the filter screen. The third ring body is slidably sleeved on the second ring body. The mesh size of the filter screen is larger than the mesh size of the collecting net.

[0016] As mentioned above, the mesh size of the cone apex region of the filter screen is smaller than the mesh size of the other regions.

[0017] As described above, the first ring body is provided with a fixed space for the insertion of the first ring body and the second ring body; when the sealing flange is not fully connected to the tubular reactor, the second ring body and the third ring body are in the fixed space, and the sealing ring, together with the support layer mesh, pre-clamps the second ring body and the third ring body in the fixed space; when the sealing flange is fully connected to the tubular reactor, the sealing ring, which is deformed by compression, together with the support layer mesh, clamps the second ring body and the third ring body in the fixed space.

[0018] As described above, the first ring body is slidably arranged on the sealing flange, the support layer mesh is slidably arranged on the first ring body, and the support layer mesh is rotatably arranged on the sealing flange. A second contact surface is also provided inside the tubular reactor. When the first ring body abuts against the second contact surface, the sealing flange continues to be connected to the tubular reactor, pushing the cone apex region of the support layer mesh against the cone apex region of the collection mesh.

[0019] The beneficial effects of this invention are as follows: by arranging a sealing ring between the axial end face of the sealing flange and the contact surface arranged inside the tubular reactor, the sealing ring is gradually squeezed during the installation of the sealing flange and the tubular reactor, causing it to undergo elastic deformation. The elastically deformed sealing flange will also come into contact with the collection net. In this way, the sealing effect between the sealing flange and the tubular reactor is enhanced, and the sealing effect between the collection net and the sealing flange is also improved, thereby effectively increasing the collection rate of carbon nanotubes. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0021] Figure 1 This is a schematic diagram of the three-dimensional structure of a tubular reactor;

[0022] Figure 2 This is a schematic cross-sectional view of the structure when the sealing flange and the tubular reactor are not fully connected.

[0023] Figure 3 for Figure 2 Enlarged structural diagram at point A in the diagram;

[0024] Figure 4 for Figure 2 Enlarged structural diagram at point B in the diagram;

[0025] Figure 5 A schematic cross-sectional view of the structure when the sealing flange is fully connected to the tubular reactor;

[0026] Figure 6 for Figure 5 Enlarged structural diagram at point C;

[0027] Figure 7 for Figure 5 A magnified structural diagram at point D in the diagram.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. Tubular reactor; 2. Sealing flange; 3. Collection net; 4. Sealing ring; 5. First contact surface; 6. Insert section; 7. Connecting section; 8. First ring body; 9. Support layer net; 10. Second ring body; 11. Filter screen; 12. Third ring body; 13. Second contact surface. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the following will be described in conjunction with the appendix. Figure 1 To be continued Figure 7 The present invention will now be described in further detail.

[0031] In this embodiment of the invention, a single-walled carbon nanotube (SCHNT) collection device is provided for collecting SCHNTs entering the deposition zone of a tubular reactor 1. The device includes a collection net 3 arranged within the deposition zone of the tubular reactor 1. A sealing flange 2 near the deposition zone of the tubular reactor 1 is connected to the end of the tubular reactor 1 by a screw connection. The collection net 3 is mounted on the sealing flange 2, and a sealing ring 4 is installed at the axial end of the sealing flange 2. A first contact surface 5 is provided inside the tubular reactor 1. During the stroke of inserting the sealing flange 2 into the tubular reactor 1 and rotating it, the end of the sealing flange 2, in conjunction with the first contact surface 5, compresses the sealing ring 4, causing elastic deformation. The elastically deformed sealing ring 4 then comes into contact with the collection net 3.

[0032] Specifically, the tubular reactor 1 is a tubular structure with open ends made of transparent quartz material, and its two ends are sealed with sealing flanges 2. The interior of the tubular reactor 1 is divided into a cracking zone, a synthesis zone and a deposition zone along the axial direction (e.g., from left to right) according to actual needs. That is, the catalyst, which has been heated and gasified, is carried into the tubular reactor 1 by the carrier gas and cracked together with hydrocarbons in the cracking zone to obtain active carbon atoms. The gaseous catalyst and active carbon atoms react fully in the synthesis zone to generate single-walled carbon nanotubes. The single-walled carbon nanotubes follow the gas flow to the deposition zone and are collected by the collection net 3. In the prior art, the collection net 3 is basically planar and is installed in the deposition zone by interference fit. However, due to installation errors and insufficient material rigidity, there are gaps between the two. The gas flow carrying catalyst particles and carbon nanotubes may leak through the gaps, and the leakage will cause pollution to the downstream pipeline of the tubular reactor 1.

[0033] Therefore, based on the above-mentioned technical problems, in this embodiment, the installation position and sealing structure of the collection net 3 are adjusted. Specifically, the connection between the sealing flange 2 near the deposition zone of the tubular reactor 1 and the tubular reactor 1 is changed from using multiple bolts for fixing to a screw connection between the sealing flange 2 and the tubular reactor 1. That is, the sealing flange 2 can extend into a threaded section 6, and the end of the tubular reactor 1 can also be provided with a threaded connecting section 7. By rotating the sealing flange 2, the section 6 and the connecting section 7 are connected through threaded engagement. Then, the collection net 3 is placed on the sealing flange 2, such as inside the section 6 on the sealing flange 2, and a sealing ring 4 is fixedly arranged at the end of the section 6. Since the preparation of single-walled carbon nanotubes is temperature-dependent... Therefore, the sealing ring 4 is made of quartz-based composite elastic material. A first abutment surface 5 is provided at the end of the joint 7 away from the sealing flange 2. That is, as the sealing flange 2 is connected to the tubular reactor 1, the sealing ring 4 will be driven to gradually contact the first abutment surface 5. Finally, the insertion section 6 cooperates with the first abutment surface 5 to form a compression on the sealing ring 4, causing the sealing ring 4 to undergo elastic deformation. In this way, the sealing effect between the sealing flange 2 and the tubular reactor 1 is effectively improved. The elastically deformed sealing ring 4 will also contact the collection net 3. Obviously, the structure used for sealing, such as the common sealing ring, can achieve a sealing effect when it is sandwiched between two contact surfaces based on elastic deformation. Thus, an additional sealing structure is added at the connection position between the collection net 3 and the sealing flange 2.

[0034] As can be seen from the above, the beneficial effects of this embodiment are as follows:

[0035] Firstly, the change in the connection method between the sealing flange 2 and the tubular reactor 1 makes it easier to quickly disassemble and assemble the collection net 3 to collect single-walled carbon nanotubes.

[0036] Secondly, by arranging a sealing ring 4 between the axial end face of the sealing flange 2 and the contact surface arranged inside the tubular reactor 1, the sealing ring 4 is gradually squeezed during the installation of the sealing flange 2 and the tubular reactor 1, causing it to undergo elastic deformation, thereby enhancing the sealing effect between the sealing flange 2 and the tubular reactor 1.

[0037] Third, the elastically deformed sealing flange 2 will also come into contact with the collection net 3, which can improve the sealing effect between the collection net 3 and the sealing flange 2, thereby effectively improving the collection rate of carbon nanotubes.

[0038] Furthermore, the sealing ring 4 has an isosceles trapezoidal cross-section, with its upper bottom surface connected to the end of the sealing flange 2 and its lower bottom surface abutting against the first contact surface 5.

[0039] Specifically, the sealing ring 4 is designed with a trapezoidal cross-section. During the connection of the sealing flange 2 and the tubular reactor 1, the contact part between the sealing ring 4 and the inner wall of the connecting section 7 is the part of the isosceles trapezoidal inclined surface near the bottom, which is basically in line contact. This can reduce the contact area between the sealing ring 4 and the tubular reactor 1 when the sealing flange 2 is disassembled and assembled, thereby reducing wear. Moreover, after the sealing ring 4 is compressed and undergoes elastic deformation, the contact area between the inclined surface and the inner wall of the tubular reactor 1 will be larger than that of a rectangle or circle, thereby improving the sealing effect.

[0040] Preferably, a first ring body 8 is installed on the sealing flange 2, a support layer mesh 9 is installed on the first ring body 8, a second ring body 10 is installed in the cone bottom area of ​​the collecting mesh 3, the second ring body 10 is slidably sleeved on the first ring body 8, and the sealing ring 4 that undergoes elastic deformation abuts against the second ring body 10.

[0041] Specifically, in the existing technology, the collection net 3 is not equipped with a corresponding support structure. As the number of single-walled carbon nanotubes collected on the collection net 3 increases, the mesh will become clogged, hindering the airflow. This increases the load on the collection net 3, and in severe cases, it may cause the collection net 3 to deform and enlarge the mesh, resulting in leakage of the collected single-walled carbon nanotubes. Therefore, in this embodiment, a first ring body 8 is installed on the sealing flange 2, and a support layer mesh 9 is set on the first ring body 8. The support layer mesh 9 is woven from high-strength quartz fiber, and the mesh size is much larger than that of the collection net 3. This will not hinder the airflow and will provide strong support for the collection net 3.

[0042] Furthermore, the support layer mesh 9 has a conical structure, with the cone apex facing away from the sealing flange 2, and the shape of the collection mesh 3 is adapted to the shape of the support layer mesh 9.

[0043] Specifically, due to the uneven distribution of airflow velocity within the tubular reactor 1, i.e., the airflow velocity is high in the center and low near the inner wall, the high-speed airflow in the center will carry small-diameter carbon nanotubes, such as those with a diameter of 0.1 to 5 micrometers, through the mesh quickly (because the particles have low inertia, they do not have time to be adsorbed by the mesh surface), forming a blind zone for interception in the center. At the same time, in the low-speed airflow on the tube wall, large-diameter carbon nanotubes (8-10 micrometers) are prone to accumulate at the edge of the mesh surface, which will further reduce the interception efficiency after clogging the mesh.

[0044] Therefore, in this embodiment, the structure of the support layer mesh 9 is set as a conical structure with a cone angle of 15 degrees. The shape of the collecting mesh 3 is adapted to the shape of the support layer mesh 9. This inclined mesh surface forms a differentiated contact angle with the airflow at different radial positions. The side of the conical mesh forms an angle of approximately 45 degrees with the high-speed airflow, which prolongs the contact time between the airflow and the mesh surface. Small-diameter carbon nanotubes have more time to be intercepted by the mesh surface to eliminate the central interception blind zone. In the low-speed airflow area of ​​the tube wall, large-diameter carbon nanotubes are intercepted along the side and accumulate towards the bottom of the cone, which reduces the area of ​​the side mesh pores that are blocked and maintains continuous interception capability.

[0045] In an optional embodiment, the mesh size of the cone apex region of the collecting net 3 is smaller than that of the cone body region, and the mesh size of the cone body region is smaller than that of the cone bottom region. That is, based on the fact that the particle size of the agglomerated single-walled carbon nanotubes is between 0.1 and 10 micrometers, the mesh size of the cone region of the collecting net 3 is set to 0.1 to 5 micrometers, the mesh size of the cone body region is between 5 and 8 micrometers, and the mesh size of the cone bottom region is between 8 and 10 micrometers. By intercepting the agglomerated single-walled carbon nanotubes of different sizes in different regions, it is possible to avoid the accumulation of different particle sizes in a certain area, which would increase the resistance to airflow. Thus, the turbulence of airflow is basically eliminated, and the impact on temperature fluctuations in the deposition area is also reduced, making the growth environment of single-walled carbon nanotubes suitable.

[0046] Preferably, a filter screen 11 is arranged on the side of the collecting net 3 away from the supporting layer net 9. The filter screen 11 is used to collect catalyst particles. The shape of the filter screen 11 is adapted to the shape of the collecting net 3. A third ring body 12 is installed in the conical bottom area of ​​the filter screen 11. The third ring body 12 is slidably sleeved on the second ring body 10. The mesh size of the filter screen 11 is larger than the mesh size of the collecting net 3.

[0047] Specifically, in the aforementioned embodiments, when using the collecting net 3 to collect single-walled carbon nanotubes, catalyst particles are sometimes collected together. This mixed collection of catalyst particles and carbon nanotubes lacks stratified interception, resulting in catalyst residue adhering to the surface of the carbon nanotubes. Subsequent purification requires additional treatment of this catalyst residue. Therefore, in this embodiment, a filter net 11 for collecting catalyst particles is arranged on the side of the collecting net 3 opposite to the support layer net 9, and the shape of the filter net 11 is adapted to the shape of the collecting net 3. According to existing technology, the particle size of the catalyst is between 5 and 20 micrometers. Therefore, the mesh size of the filter screen 11 should be designed to be between 10 and 20 micrometers to allow single-walled carbon nanotubes to pass through. Although it cannot completely intercept catalyst particles, it can effectively reduce the amount of residual catalyst in the carbon nanotubes. In optional embodiments, the mesh size of the cone apex region of the filter screen 11 is smaller than that of the other regions. For example, the mesh size of the cone apex region of the filter screen 11 is between 5 and 10 micrometers, while the mesh size of the other parts is between 10 and 20 micrometers. That is, its purpose is to adapt to the high-speed airflow in the center, avoid the leakage of small-diameter catalyst particles, and not obstruct the small-diameter carbon nanotubes.

[0048] Furthermore, the first ring body 8 is provided with a fixed space for the insertion of the first ring body 8 and the second ring body 10; when the sealing flange 2 is not fully connected to the tubular reactor 1, the second ring body 10 and the third ring body 12 are in the fixed space, and the sealing ring 4, together with the support layer mesh 9, pre-clamps the second ring body 10 and the third ring body 12 in the fixed space; when the sealing flange 2 is fully connected to the tubular reactor 1, the sealing ring 4, which is deformed by compression, together with the support layer mesh 9, clamps the second ring body 10 and the third ring body 12 in the fixed space.

[0049] Specifically, the collecting net 3 and the filter net 11 are replaced after each use to collect single-walled carbon nanotubes and catalysts. When using the collecting net 3 and the filter net 11, they need to be clamped and fixed. When disassembly is required, they should not be clamped and fixed, but only slightly clamped. In this embodiment, a fixing space is provided on the first ring body 8. The fixing space is composed of the first ring body 8 and the side of the sealing ring 4 away from the inner wall of the tubular reactor 1. The fixing space allows the bottom of the support layer net 9, the second ring body 10 and the third ring body 12 to be inserted together. Then, the sealing ring 4 can be used to perform a preliminary pre-clamping of the three. That is, with this pre-clamping, when connecting the sealing flange 2 and the tubular reactor 1, the support layer net 9, the collecting net 3 and the filter net 11 can be basically kept stably installed on the first ring body 8. Afterwards, as the sealing ring 4 is squeezed and undergoes elastic deformation, the bottom of the support layer net 9, the second ring body 10 and the third ring body 12 are also clamped and fixed (because the middle part of the sealing ring 4 will expand to both sides during the compression process).

[0050] Furthermore, the first ring body 8 is slidably arranged on the sealing flange 2, the support layer mesh 9 is slidably arranged on the first ring body 8, and the support layer mesh 9 is rotatably arranged on the sealing flange 2. A second contact surface 13 is also provided inside the tubular reactor 1. When the first ring body 8 abuts against the second contact surface 13, the sealing flange 2 continues to be connected to the tubular reactor 1, pushing the cone top area of ​​the support layer mesh 9 against the cone top area of ​​the collection mesh 3.

[0051] Specifically, during use, there should be a gap between the collecting net 3 and the filter net 11, and there should also be a gap between the collecting net 3 and the support layer net 9. This ensures that the target object is intercepted while also ensuring smooth airflow. Therefore, in this embodiment, the first ring 8 is slidably arranged on the sealing flange 2 along the axial direction, and then the support layer net 9 is slidably arranged on the first ring 8. However, the support layer net 9 is rotatably connected to the sealing flange 2, meaning that the rotation of the sealing flange 2 will not significantly cause the support layer net 9 to rotate. However, during the axial connection between the sealing flange 2 and the tubular reactor 1, the support layer net 9 can be pushed to move together. Furthermore, a second contact surface 13 is arranged inside the tubular reactor 1 to prevent the first ring 8 from moving with the sealing flange 2. That is, when the sealing ring 4 contacts the first contact surface 5 but has not yet been squeezed, the first ring 8... 8 is blocked by the second contact surface 13, and the sealing flange 2 continues to move, squeezing the sealing ring 4 and pushing the support layer mesh 9 to move together. The side of the elastically deformed sealing ring 4 expands and squeezes the third ring body 12 of the outer liner. The movement of the support layer mesh 9 squeezes the second ring body 10 (the two squeeze each other through a wedge fit). Thus, under the action of the interaction force, the positions of the support layer mesh 9, the second ring body 10 and the third ring body 12 are fixed and restricted. During the movement of the support layer mesh 9, its cone apex area pushes against the inner side of the cone apex area of ​​the collection mesh 3, and the cone apex area of ​​the collection mesh 3 pushes against the inner side of the cone apex area of ​​the filter mesh 11. Thus, for the collection mesh 3 and the filter mesh 11, the cone apex and cone trough are restricted, and the rest of the part is in a suspended state. This can ensure that the target object is intercepted while ensuring the smooth flow of air.

[0052] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of the claims of the present invention.

Claims

1. A single-walled carbon nanotube collection device for collecting single-walled carbon nanotubes entering a deposition zone of a tube reactor, comprising a collection web disposed within the deposition zone of the tube reactor, characterized in that, The sealing flange is connected between the end of the tubular reactor and the sealing flange by screwing, the collecting net is installed on the sealing flange, and a sealing ring is installed at the axial end of the sealing flange, and a first abutting surface is arranged in the tubular reactor; In the process of inserting the sealing flange into the tubular reactor and rotating, the end of the sealing flange is matched with the first abutting surface to extrude the sealing ring to be elastically deformed, and the elastically deformed sealing ring abuts against the collecting net; A first ring body is installed on the sealing flange, a supporting layer net is installed on the first ring body, a second ring body is installed at the conical bottom region of the collecting net, the second ring body is slidably sleeved on the first ring body, and the elastically deformed sealing ring abuts against the second ring body; The supporting layer net has a conical structure, and the conical top is away from the sealing flange, and the shape of the collecting net is matched with the shape of the supporting layer net. The mesh size of the conical top region of the collecting net is smaller than the mesh size of the conical body region, and the mesh size of the conical body region is smaller than the mesh size of the conical bottom region.

2. The single-walled carbon nanotube collection device of claim 1, wherein, The cross section of the sealing ring is in isosceles trapezoidal structure, the upper base of the cross section is connected to the end of the sealing flange, and the lower base abuts against the first abutting surface.

3. The single-walled carbon nanotube collection device of claim 1, wherein, The side of the collecting net away from the supporting layer net is provided with a filter net, the filter net is used for collecting catalyst particles, the shape of the filter net is matched with the shape of the collecting net, a third ring body is installed at the conical bottom region of the filter net, and the third ring body is slidably sleeved on the second ring body; and the mesh size of the filter net is larger than the mesh size of the collecting net.

4. The single-walled carbon nanotube collection device of claim 3, wherein, The mesh size of the conical top region of the filter net is smaller than the mesh size of the rest region of the filter net.

5. The single-walled carbon nanotube collection device of claim 4, wherein, The first ring body is slidably arranged on the sealing flange, the supporting layer net is slidably arranged on the first ring body, and the supporting layer net is rotatably arranged on the sealing flange, and a second abutting surface is further arranged in the tubular reactor, when the first ring body abuts against the second abutting surface, the conical top region of the supporting layer net is pushed to abut against the conical top region of the collecting net in the process of continuing to connect the sealing flange and the tubular reactor.

6. The single-walled carbon nanotube collection device of claim 5, wherein, ​

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