Carbon nanotube production system

Abstract

The invention belongs to the technical field of carbon nano tube production, and particularly relates to a carbon nano tube production system which is characterized in that a prepared catalyst is placed in a feeding mechanism, the catalyst is guided into a reaction tube in a reactor body through a feeding tube by utilizing the feeding mechanism, the reaction tube is heated, and introduction of inert gas is kept; when the temperature in the reaction tube reaches a proper reaction temperature, the catalyst expands, and the carbon source gas flows through the catalyst through the gas holes of the distribution plate, so that the carbon nanotube grows; after the catalyst reaction is completed, a black granular product is generated, then the motor is controlled to stop rotating, the introduction of the carbon source gas is stopped, the introduction of inert gas is continued, and after the product is cooled, the black product above the distribution plate is collected to obtain the carbon nanotube. Dead zones formed by over-low local gas velocity can be avoided, and accumulation and agglomeration of the catalyst are prevented.

Description

Technical Field

[0001] This invention belongs to the field of carbon nanotube production technology, specifically a carbon nanotube production system. Background Technology

[0002] Carbon nanotubes are nanomaterials that can be classified into single-walled and multi-walled carbon nanotubes based on the number of wall layers, with lengths ranging from micrometers to millimeters. Among the various production methods for carbon nanotubes, fluidized bed chemical vapor deposition has become the mainstream choice for industrial production due to its unique advantages.

[0003] The production process of carbon nanotubes in a fluidized bed reactor requires strict control over every step to ensure reaction stability and product quality. Regarding raw materials, the solid feedstock is a supported catalyst, typically using transition metals such as Fe, Co, and Ni as active components, supported on Al2O3, SiO2, or MgO to form 100-300 μm particles. These particles are added through the feed inlet at the top of the reactor and eventually settle on a porous gas distribution plate at the bottom to form the initial bed. The gaseous feedstock includes carbon source gas, carrier gas, and reducing gas, which are introduced through the inlet below the distribution plate. After being uniformly distributed in the pre-distribution chamber, the gas passes through the small holes in the distribution plate into the reaction zone. The specific production process is as follows: First, inert gas replacement is performed, and nitrogen or argon is introduced to purge the reactor for 30 minutes to remove air impurities and ensure that the oxygen content is below 0.5%. Then, the heating system is started, and the temperature is raised to 650-1000℃ at a rate of 5-10℃ / min. At the same time, hydrogen is introduced to reduce and activate the catalyst for 30-60 minutes, so that the metal oxide is converted into nano-metal particles. After the temperature stabilizes, the gas flow rate is adjusted to 1.5-3 times the critical fluidization rate, so that the catalyst particles are in a suspended fluidized state under the action of the airflow. Then, carbon source gas is introduced in proportion. The carbon source is decomposed into carbon atoms at the active sites of the catalyst, and carbon nanotubes are formed through adsorption, diffusion and ordered arrangement. After the reaction continues for 30-120 minutes, the carbon source is stopped, and inert gas is continued to be introduced to cool to room temperature. Finally, the product is collected, and the unreacted catalyst is recycled by a cyclone separator.

[0004] During the growth of carbon nanotubes, amorphous carbon is deposited on the surface of catalyst particles, increasing the adhesion between particles. At the same time, the high aspect ratio of carbon nanotubes and van der Waals forces cause particles to entangle with each other, forming larger agglomerates. Meanwhile, the fluidization state fluctuates. If the gas distribution is uneven or the gas velocity is not properly controlled, a "dead zone" with too low a flow rate will appear in some areas, and the catalyst particles cannot be fully suspended and are prone to agglomeration.

[0005] When catalyst agglomeration occurs, it is impossible to maintain a good fluidization state, resulting in insufficient contact between carbon source gas and catalyst, excessively high carbon source concentration in some areas and insufficient catalyst in others. This ultimately leads to fluctuations in carbon nanotube yield and also tends to result in a wide product particle size distribution. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies and solve the aforementioned technical problems, this invention proposes a carbon nanotube production system, as detailed below.

[0007] A carbon nanotube production system includes the following steps: S1: The prepared catalyst is placed into the feeding mechanism. The catalyst is introduced into the reaction tube in the reactor body through the feeding pipe using the feeding mechanism. The reaction tube is heated and inert gas is kept flowing through it. S2: When the temperature inside the reaction tube reaches the appropriate reaction temperature, the catalyst expands, and the carbon source gas flows through the pores of the distribution plate through the catalyst, causing carbon nanotubes to grow. S3: After the catalyst reaction is complete, a black granular product is generated. Then, the motor is stopped and the carbon source gas is stopped, while the inert gas continues to be introduced. After the product has cooled down, the first electric actuator is controlled to retract, thereby pulling the distribution plate down and moving the black product and reaction components down. After the distribution plate, black product and reaction components have moved into the auxiliary tube, the first electric actuator is controlled to stop retracting, and the servo motor is controlled to drive the lead screw to rotate. The rotating lead screw drives the mounting plate and auxiliary tube to move down as a whole. After the auxiliary tube separates from the reaction tube, the black product above the distribution plate can be collected to obtain carbon nanotubes.

[0008] In a preferred embodiment of the present invention, the reactor body in step S1 includes a reaction tube; an auxiliary tube is provided at the bottom of the reaction tube, and the inner diameter of the auxiliary tube is the same as that of the inner diameter of the reaction tube; and the auxiliary tube is a quartz tube; the auxiliary tube is mounted on a mounting plate at the bottom, and an air inlet pipe is mounted at the bottom of the mounting plate. The mounting plate is threaded with a lead screw, which is connected to a servo motor at the bottom, and the servo motor is installed at the bottom of the reactor body; a sealing ring is fixed to the top of the auxiliary tube, and the sealing ring is sealed to the bottom of the reaction tube. The reaction tube is equipped with a reaction assembly; the reaction assembly includes a distribution plate, which slides inside the reaction tube; the distribution plate has multiple rings of evenly arranged air holes. The distribution plate has a first annular groove at its bottom, and the cross-section of the first annular groove is convex; a first annular plate slides inside the first annular groove; a horizontal plate is fixed to the inner ring of the first annular plate, and a motor is fixed to the bottom of the horizontal plate; a rectangular rod is installed on the drive shaft of the motor, and the rectangular rod extends into the interior of the distribution plate. The first ring plate is equipped with a first electric actuator at its bottom, and the other side of the first electric actuator is mounted on the mounting plate; the distribution plate is provided with a cylinder at its top, and the outer ring surface of the cylinder is provided with evenly arranged air grooves. A second annular groove is formed below the cylinder on the distribution plate, and the cross-section of the second annular groove is C-shaped; a first sliding shaft is fixed at the bottom of the cylinder, and the first sliding shaft slides in the second annular groove. The cylinder is fitted with an annular chamber, and the air groove is located inside the annular chamber, and the top of the annular chamber is conical; the inner circle of the annular chamber has uniformly arranged through holes, and the outer circle of the annular chamber has uniformly arranged oblique holes. The inner ring of the annular compartment is equipped with a drive component.

[0009] In a preferred embodiment of the present invention, the reactor body is provided with two heating boxes, one of which is mounted on the reactor body and the other is mounted on the other heating box via a hinge; a reaction tube is installed inside the heating box, and the reaction tube is a quartz tube. The top of the reaction tube is equipped with a feed pipe and an exhaust pipe, and the feed pipe is connected to an external feeding mechanism; the exhaust pipe is connected to an external bag filter. The drive assembly includes a vertical cylinder; the vertical cylinder is disposed in the inner ring of the annular compartment, and the bottom of the vertical cylinder is in contact with the distribution plate, while the top of the vertical cylinder is separated from the top of the annular compartment. A drive rod is mounted on the top of the rectangular rod; a first gear is fixed on the drive rod; a flat plate is fixed to the inner ring of the vertical cylinder; a second gear is rotatably mounted on the bottom of the flat plate, and the second gear meshes with the first gear. The inner ring of the vertical cylinder has evenly arranged toothed grooves, and the second gear meshes with the toothed grooves; the inner ring of the annular compartment is fixed with a driven plate; the other side of the driven plate is disposed on the outer ring of the vertical cylinder; The reaction chamber is equipped with a fixed rod, which is inserted into the cylinder.

[0010] In a preferred embodiment of the present invention, a plurality of extension plates are fixed to the outer ring of the annular compartment; a vertical rod is rotatably mounted below the extension plates, and a striking rod is fixed on the vertical rod; The top of the extension plate has two rotating wheels, one of which is fixed to the upright and the other is attached to the reaction tube.

[0011] In a preferred embodiment of the present invention, the outer ring of the vertical cylinder is provided with a slide rail, and the driven plate slides within the slide rail; A push shaft is fixed to the bottom of the driven plate, and the bottom of the push shaft is circular; an evenly arranged arc-shaped block is fixed between the vertical cylinder and the annular chamber, and the arc-shaped block is higher in the middle and lower on both sides.

[0012] In a preferred embodiment of the present invention, a cleaning chamber is provided between the cylinder and the reaction tube, and the cross-section of the cleaning chamber is triangular. The cleaning chamber has evenly arranged spray holes on its sloping top surface; the cylinder has air passages that are connected to the inner ring of the cylinder and the cleaning chamber.

[0013] In a preferred embodiment of the present invention, a rotating shaft is fixed to the top of the annular compartment, and a spiral plate is fixed to the rotating shaft; The bottom end of the spiral plate is staggered with the extension plate; the spiral plate is attached to the reaction tube.

[0014] In a preferred embodiment of the present invention, the top of the annular chamber is provided with uniformly arranged blowholes.

[0015] In a preferred embodiment of the present invention, a long plate is fixed to the bottom of the extension plate, and the cross-section of the long plate is triangular. The long plate is attached to the inner ring of the reaction tube.

[0016] In a preferred embodiment of the present invention, a circular ring is provided below the distribution plate; The ring is fixed with evenly arranged round rods, and the round rods are initially inserted into the vent holes located between the cylinder and the reaction tube. The inner ring of the circular ring is fixed with a limiting plate, and a rectangular groove is provided in the middle of the limiting plate, and a rectangular rod passes through the rectangular groove; A second electric push rod is installed at the bottom of the horizontal plate; a third annular groove is opened at the bottom of the ring, and the cross-section of the third annular groove is C-shaped; a second sliding shaft is fixed at the top of the second electric push rod, and the second sliding shaft slides in the third sliding groove.

[0017] The beneficial effects of this invention are as follows: 1. The carbon nanotube production system of the present invention, by setting a combination of clockwise rotation of the distribution plate and counterclockwise rotation of the annular chamber, creates a moving airflow field through the pores on the distribution plate, avoiding dead zones caused by excessively low local gas velocities and preventing catalyst agglomeration; at the same time, the oblique holes on the outer ring of the annular chamber continuously spray directional airflow, which not only directly disperses the initial agglomerates formed by amorphous carbon deposition, but also pushes the agglomerates to impact the inner wall of the reaction tube, using the impact force to achieve secondary dispersion of the agglomerates, significantly reducing the probability of the formation of large-sized agglomerates; thus, the catalyst is always maintained in a uniform bubbling fluidized state, avoiding the problems of excessively high local carbon source concentration or insufficient local catalyst activity in traditional devices.

[0018] 2. The carbon nanotube production system of the present invention, through the limiting design of the annular chamber, confines the catalyst within the annular reaction area between the annular chamber and the reaction tube, making the distance between the catalyst and the heating box on the reactor body relatively uniform. This avoids the problem of insufficient heating caused by some catalysts being located in the middle of the reaction tube in traditional devices, ensuring that the temperature gradient in the entire reaction area is controlled within a very small range. The combination of temperature uniformity and stable fluidization state of the catalyst makes the reaction conditions of the catalyst active sites tend to be consistent, effectively controlling the growth of carbon nanotube diameter and wall number, and reducing the problems of low yield of single-wall carbon nanotubes and wide distribution of wall number and diameter of multi-wall carbon nanotubes.

[0019] 3. The carbon nanotube production system of the present invention, when the cylinder rotates, drives the cleaning chamber to rotate synchronously, which can scrape up and collect the catalyst accumulated on the surface of the distribution plate. At the same time, the carbon source gas in the inner ring of the cylinder is introduced into the cleaning chamber through the gas channel and sprayed out at high speed through the nozzle, blowing the collected catalyst into the fluidization area, so that the catalyst re-enters the up-and-down tumbling state, ensuring that each catalyst particle can contact the carbon source gas, realizing the full-range fluidization of the catalyst in the reaction area, and further improving the contact efficiency between the carbon source gas and the catalyst. At the same time, the long plate rotates synchronously with the extension plate and scrapes the inner wall of the reaction tube, thereby timely removing the attached catalyst particles and carbon deposits, avoiding the temperature field distortion caused by the formation of a heat insulation layer on the inner wall of the traditional device, and preventing the attached catalyst from forming stubborn agglomerates due to long-term high-temperature sintering. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a diagram of the internal structure of the reaction tube in this invention; Figure 3 This is a structural diagram of the reaction components in this invention; Figure 4 This is an exploded view of the structure of the reaction component in this invention; Figure 5 This is the present invention. Figure 4 Enlarged view of a portion of point A in the middle; Figure 6 This is the present invention. Figure 4 Enlarged view of a section at point B in the middle; Figure 7 This is the present invention. Figure 4 Enlarged view of a section at point C; Figure 8 This is a structural diagram of the cylinder and cleaning chamber in this invention; Figure 9 This is a top view of the overall structure of the invention; Figure 10 This is the present invention. Figure 9 Sectional view at point DD; Figure 11 This is the present invention. Figure 10 Enlarged view of a section at point E in the middle; Figure 12 This is the present invention. Figure 10 Enlarged view of a section at point F in the middle; Figure 13 This is the present invention. Figure 10 Enlarged view of a section at point G.

[0022] In the diagram: 1. Reaction tube; 11. Heating box; 12. Feed pipe; 13. Gas outlet pipe; 2. Auxiliary pipe; 21. Mounting plate; 22. Gas inlet pipe; 23. Lead screw; 3. Distribution plate; 31. Gas hole; 32. First annular groove; 33. First annular plate; 34. Horizontal plate; 35. Rectangular rod; 36. First electric actuator; 4. Cylinder; 41. Gas groove; 42. Second annular groove; 43. First sliding shaft; 44. Annular chamber; 45. Through hole; 46. Inclined hole; 5. Vertical cylinder; 51. Drive rod; 52. First gear; 53. Flat plate; 54. Second gear; 55. Gear groove; 56. Driven plate; 57. Slide rail; 58. Insert rod; 59. Push shaft; 591. Arc block; 6. Extension plate; 61. Vertical rod; 62. Striking rod; 63. Rotating wheel; 64. Long plate; 7. Cleaning chamber; 71. Spray hole; 72. Air passage; 8. Spiral plate; 81. Blow hole; 9. Ring; 91. Round rod; 92. Limiting plate; 93. Second electric push rod; 94. Third annular groove; 95. Second slide shaft. Detailed Implementation

[0023] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0024] like Figures 1 to 13 As shown, the carbon nanotube production system of the present invention includes the following steps: S1: The prepared catalyst is placed into the feeding mechanism. The catalyst is introduced into the reaction tube 1 in the reactor body through the feeding pipe 12 by the feeding mechanism. The reaction tube 1 is heated and inert gas is kept flowing in. S2: When the temperature inside the reaction tube 1 reaches the appropriate reaction temperature, the catalyst expands, and the carbon source gas flows through the pores 31 of the distribution plate 3 through the catalyst, causing carbon nanotubes to grow. S3: After the catalyst reaction is complete, a black granular product is generated. Then, the motor is stopped and the carbon source gas is stopped, while the inert gas continues to be introduced. After the product cools down, the first electric actuator 36 is contracted, thereby pulling the distribution plate 3 down and moving the black product and reaction components down. After the distribution plate 3, black product and reaction components move down into the auxiliary tube 2, the first electric actuator 36 is stopped contracting, and the servo motor is controlled to drive the lead screw 23 to rotate. The rotating lead screw 23 drives the mounting plate 21 and the auxiliary tube 2 to move down as a whole. After the auxiliary tube 2 separates from the reaction tube 1, the black product above the distribution plate 3 can be collected to obtain carbon nanotubes.

[0025] In one embodiment of the present invention, in step S1, the reactor body includes a reaction tube 1, and an auxiliary tube 2 is provided at the bottom of the reaction tube 1. The inner diameter of the auxiliary tube 2 is the same as that of the inner diameter of the reaction tube 1. The auxiliary tube 2 is a quartz tube. The auxiliary tube 2 is installed on a mounting plate 21 at the bottom, and an air inlet pipe 22 is installed at the bottom of the mounting plate 21. The mounting plate 21 is threaded with a lead screw 23, which is connected to a servo motor at the bottom, and the servo motor is installed at the bottom of the reactor body; the top of the auxiliary pipe 2 is fixed with a sealing ring, and the sealing ring is sealed to the bottom of the reaction pipe 1. The reaction tube 1 is equipped with a reaction assembly; the reaction assembly includes a distribution plate 3, which slides inside the reaction tube 1; the distribution plate 3 has multiple rings of evenly arranged air holes 31. The distribution plate 3 has a first annular groove 32 at its bottom, and the cross-section of the first annular groove 32 is convex; a first annular plate 33 slides inside the first annular groove 32; a horizontal plate 34 is fixed inside the first annular plate 33, and a motor is fixed at the bottom of the horizontal plate 34; a rectangular rod 35 is installed on the drive shaft of the motor, and the rectangular rod 35 extends into the interior of the distribution plate 3. The first ring plate 33 is equipped with a first electric push rod 36 at the bottom, and the other side of the first electric push rod 36 is installed on the mounting plate 21; the distribution plate 3 is provided with a cylinder 4 at the top, and the outer ring surface of the cylinder 4 is provided with uniformly arranged air grooves 41. A second annular groove 42 is provided on the distribution plate 3 below the cylinder 4, and the cross-section of the second annular groove 42 is C-shaped; a first sliding shaft 43 is fixed at the bottom of the cylinder 4, and the first sliding shaft 43 slides in the second annular groove 42. The cylinder 4 is fitted with an annular chamber 44, and the air groove 41 is located inside the annular chamber 44, and the top of the annular chamber 44 is conical; the inner circle of the annular chamber 44 is provided with uniformly arranged through holes 45, and the outer circle of the annular chamber 44 is provided with uniformly arranged oblique holes 46. The inner ring of the annular compartment 44 is equipped with a drive assembly; In this embodiment, the reactor body is provided with two heating boxes 11, one of which is mounted on the reactor body and the other is mounted on the other heating box 11 via a hinge; a reaction tube 1 is installed inside the heating box 11, and the reaction tube 1 is a quartz tube. The top of the reaction tube 1 is equipped with a feed pipe 12 and an exhaust pipe 13, and the feed pipe 12 is connected to an external feeding mechanism; the exhaust pipe 13 is connected to an external bag filter. The drive assembly includes a vertical cylinder 5; the vertical cylinder 5 is disposed in the inner ring of the annular compartment 44, and the bottom of the vertical cylinder 5 is in contact with the distribution plate 3, while the top of the vertical cylinder 5 is separated from the top of the annular compartment 44. A drive rod 51 is installed on the top of the rectangular rod 35; a first gear 52 is fixed on the drive rod 51; a flat plate 53 is fixed on the inner ring of the vertical cylinder 5; a second gear 54 rotates at the bottom of the flat plate 53, and the second gear 54 meshes with the first gear 52. The inner ring of the vertical cylinder 5 is provided with evenly arranged toothed grooves 55, and the second gear 54 meshes with the toothed grooves 55; the inner ring of the annular chamber 44 is fixed with a driven plate 56; the other side of the driven plate 56 is provided on the outer ring of the vertical cylinder 5. The reaction chamber is fixed with a rod 58, which is inserted into the cylinder 4.

[0026] First, the prepared catalyst is placed into the feeding mechanism. The catalyst is then introduced into the reaction tube 1 through the feeding pipe 12. The catalyst falling into the reaction tube 1 first lands on the conical profile at the top of the annular chamber 44, and then slides into the space between the annular chamber 44 and the reaction tube 1. Then, inert gas is introduced from the bottom of the auxiliary pipe 2 through the gas inlet pipe 22. The introduced gas passes through the vent holes 31 on the distribution plate 3, replacing the gas in the reaction tube 1, and flows out from the inert gas outlet pipe 13 until only inert gas remains in the reaction tube 1. Then, the heating box 11 is closed, and the reaction... The reaction tube 1 is heated while an inert gas is introduced and a small amount of hydrogen is introduced. When the temperature inside the reaction tube 1 reaches the appropriate reaction temperature, the catalyst located above the distribution plate 3 and between the first annular chamber 44 and the reaction tube 1 will begin to expand, causing the catalyst particles to tumble and jump. At this time, the catalyst enters a bubbling fluidized state. Then, the gas introduced into the bottom of the auxiliary tube 2 is switched, and the carbon source gas is introduced into the bottom of the auxiliary tube 2. The carbon source gas will flow through the pores 31 of the distribution plate 3 through the catalyst, and keep the catalyst in a tumbling and jumping state, thereby enabling the growth of carbon nanotubes. Specifically, during the production of carbon nanotubes, a motor is controlled to rotate, which in turn drives a rectangular rod 35 to rotate. Simultaneously, the rectangular rod 35 drives a distribution plate 3 to rotate clockwise from a top-view perspective. The first annular groove 32 on the distribution plate 3 rotates along the first annular plate 33. Meanwhile, a first gear 52 is fixed to the drive rod 51 at the top of the rectangular rod 35, and this first gear 52 meshes with a second gear 54, thereby driving the second gear 54 to rotate. Since the second gear 54 meshes with the tooth groove 55, and the horizontal... Plate 34 is fixed inside the vertical cylinder 5, which will cause the vertical cylinder 5 to rotate counterclockwise when viewed from above. At the same time, the second gear 54 will rotate counterclockwise around the first gear 52. Since the driven plate 56 fixed on the annular chamber 44 is located on the outer ring of the vertical cylinder 5 on the other side, it will cause the annular chamber 44 to rotate counterclockwise. Since the insertion rod 58 fixed inside the annular chamber 44 is inserted into the cylinder 4, the annular chamber 44 will drive the cylinder 4 to rotate through the insertion rod 58. The cylinder 4 will drive the first sliding shaft 43 to rotate in the second annular groove 42. More specifically, during the production of carbon nanotubes, the carbon source gas passes through multiple rings of pores 31. When the carbon source gas passes through the pores 31 located between the annular chamber 44 and the reaction tube 1, it directly acts on the catalyst, causing the catalyst to tumble and jump between the annular chamber 44 and the reaction tube 1. Simultaneously, since the distribution plate 3 rotates continuously, the pores 31 at the bottom of the catalyst move as the catalyst tumbles and jumps. This movement of the pores 31 also moves the carbon source gas, allowing it to blow across the catalyst at different locations, ensuring uniform contact between the carbon source gas and the catalyst. When the carbon source gas passes through the pores 31 between the vertical cylinder 5 and the annular chamber 44, it enters the space between them. When the carbon source gas passes through the pores 31 in the inner ring of the vertical cylinder 5, it first enters the vertical cylinder 5 and then flows upwards. When the carbon source gas reaches the top of the vertical cylinder 5, it enters from above. Between the vertical cylinder 5 and the annular chamber 44, the gas located between the vertical cylinder 5 and the annular chamber 44 first enters the gas groove 41 of the cylinder 4 through the through hole 45, and then is ejected through the inclined hole 46. The ejected carbon source gas acts on the tumbling and jumping catalyst, so that the catalyst can come into more comprehensive contact with the carbon source gas. At the same time, if the catalyst agglomerates, the ejected carbon source gas will blow away the initially formed agglomerates and blow the agglomerates to hit the inner wall of the reaction tube 1, thereby breaking up the agglomerates. At the same time, since the rotation direction of the annular chamber 44 is opposite to the rotation direction of the distribution plate 3, the carbon source gas ejected from the inclined hole 46 can come into uniform contact with the catalyst, so as to react the catalyst more comprehensively. At the same time, since the catalyst only tumbles between the annular chamber 44 and the reaction tube 1, the position of the catalyst and the heat source can be relatively uniform, avoiding the situation where some catalyst is located in the middle of the reaction tube 1, resulting in less heating of the catalyst in the middle and a temperature difference with the catalyst at the edge, which would cause deviation in the catalyst reaction. Furthermore, after the catalyst reaction is complete, a black granular product is generated. Then, the motor is stopped and the carbon source gas is stopped, while the inert gas continues to be introduced. After the product cools down, the first electric actuator 36 is contracted, thereby pulling the distribution plate 3 down and moving the black product and reaction components down. After the distribution plate 3, the black product and reaction components have moved into the auxiliary tube 2, the first electric actuator 36 is stopped contracting. Then, the servo motor is controlled to drive the lead screw 23 to rotate. The rotating lead screw 23 will drive the mounting plate 21 and the auxiliary tube 2 to move down as a whole. After the auxiliary tube 2 separates from the reaction tube 1, the black product above the distribution plate 3 can be collected to obtain carbon nanotubes. Furthermore, by combining the clockwise rotation of the distribution plate 3 with the counterclockwise rotation of the annular chamber 44, a moving airflow field is formed by the pores 31 on the distribution plate 3, avoiding dead zones caused by excessively low local gas velocities and preventing catalyst agglomeration. At the same time, the oblique holes 46 on the outer ring of the annular chamber 44 continuously eject directional airflow, which can not only directly disperse the initial agglomerates formed by amorphous carbon deposition, but also push the agglomerates to impact the inner wall of the reaction tube 1, using the impact force to achieve secondary dispersion of the agglomerates, significantly reducing the probability of the formation of large-sized agglomerates. Thus, the catalyst is always kept in a uniform bubbling fluidized state, avoiding the problems of excessively high local carbon source concentration or insufficient local catalyst activity in traditional devices. Meanwhile, the limiting design of the annular chamber 44 confines the catalyst within the annular reaction region between the annular chamber 44 and the reaction tube 1, ensuring a relatively uniform distance between the catalyst and the heating box 11 on the reactor body. This avoids the problem of insufficient heating caused by some catalysts being located in the middle of the reaction tube 1 in traditional devices, ensuring that the temperature gradient within the entire reaction region is controlled within a very small range. The combination of temperature uniformity and the stable fluidization state of the catalyst makes the reaction conditions of the catalyst active sites tend to be consistent, effectively controlling the growth of carbon nanotube diameter and wall number, and reducing the problems of low yield of single-walled carbon nanotubes and wide distribution of wall number and diameter of multi-walled carbon nanotubes.

[0027] As an embodiment of the present invention; a plurality of extension plates 6 are fixed on the outer ring of the annular compartment 44; a vertical rod 61 is rotatably mounted below the extension plate 6, and a striking rod 62 is fixed on the vertical rod 61; The top of the extension plate 6 has two rotating wheels 63, one of which is fixedly connected to the upright 61, and the other wheel 63 is attached to the reaction tube 1. In this embodiment, the outer ring of the vertical cylinder 5 is provided with a slide rail 57, and the driven plate 56 slides within the slide rail 57; The driven plate 56 is fixed with a push shaft 59 at the bottom, and the bottom of the push shaft 59 is circular; the vertical cylinder 5 and the annular chamber 44 are fixed with evenly arranged arc-shaped blocks 591, and the arc-shaped blocks 591 are high in the middle and low on both sides. Since the driven plate 56 slides within the slide rail 57 on the outer ring of the vertical cylinder 5, and since the bottom of the driven plate 56 is fixed with a push shaft 59, when the vertical cylinder 5 rotates, it will push the driven plate 56 to rotate. The rotating driven plate 56 will drive the push shaft 59 below to rotate. When the rotating push shaft 59 passes the arc-shaped block 591, it will push the push shaft 59 to move upward. The upward-moving push shaft 59 will push the driven plate 56 to move upward along the slide rail 57. The upward-moving driven plate 56 will drive the annular chamber 44 to move upward along the cylinder 4. During the upward movement, the insertion rod 58 will slide along the cylinder 4. After the push shaft 59 passes the arc block 591, the annular chamber 44 will move down to the initial position. Since there are multiple arc blocks 591, the annular chamber 44 can move up or down in a cycle. During the downward or upward movement of the annular chamber 44, the inclined hole 46 will move up and down. The carbon source gas sprayed from the inclined hole 46 will act on the catalyst at different heights, so that the sprayed carbon source gas can be contacted more comprehensively. Specifically, since the extension plate 6 is equipped with two rotating wheels 63, one of which is in contact with the reaction tube 1, when the annular chamber 44 drives the extension plate 6 to rotate, one of the rotating wheels 63 will rotate along the inner wall of the reaction tube 1, and the rotating wheel 63 itself will also rotate, which will drive the other rotating wheel 63 to rotate, thereby driving the upright rod 61 and the striking rod 62 to rotate. The rotating striking rod 62 will impact the catalyst that is flipping and jumping up and down, thereby breaking up the agglomerated catalyst and preventing the catalyst from agglomerating. At the same time, since the annular chamber 44 moves up and down in a circular manner, it will also drive the upright rod 61 and the striking rod 62 to move up and down. The up and down moving striking rod 62 will have more comprehensive contact with the catalyst and more comprehensive breaking up of the agglomerates.

[0028] As one embodiment of the present invention; a cleaning chamber 7 is provided between the cylinder 4 and the reaction tube 1, and the cross-section of the cleaning chamber 7 is triangular; The cleaning chamber 7 has evenly arranged spray holes 71 on its inclined surface at the top; the cylinder 4 has an air passage 72, which is connected to the inner ring of the cylinder 4 and the cleaning chamber 7 respectively. In this embodiment, a rotating shaft is fixed to the top of the annular chamber 44, and a spiral plate 8 is fixed on the rotating shaft; The bottom end of the spiral plate 8 is staggered with the extension plate 6; the spiral plate 8 is attached to the reaction tube 1; In this embodiment, the top of the annular chamber 44 is provided with evenly arranged blowholes 81; In this embodiment, a long plate 64 is fixed to the bottom of the extension plate 6, and the cross-section of the long plate 64 is triangular. The long plate 64 is attached to the inner ring of the reaction tube 1; During the rotation of the cylinder 4, the cleaning chamber 7 will rotate along the surface of the distribution plate 3. The rotating cleaning chamber 7 will scrape up the catalyst located on the surface of the distribution plate 3 and accumulate it on the cleaning chamber 7. Since the cleaning chamber 7 is connected to the inner ring of the cylinder 4 through the air passage 72, the carbon source gas located in the inner ring of the cylinder 4 will enter the cleaning chamber 7. Then the gas in the cleaning chamber 7 will be sprayed out through the evenly arranged nozzles 71. The sprayed gas will blow away the catalyst accumulated on the cleaning chamber 7 and make it tumble and jump. In this process, it can prevent some catalyst from accumulating in the position of the distribution plate 3 where there are no air holes 31, so that the catalyst cannot come into contact with the carbon source gas. Specifically, since the annular chamber 44 is equipped with a spiral plate 8 at the top, when the catalyst is fed, the annular chamber 44 is controlled to rotate. The rotating annular chamber 44 will drive the spiral plate 8 to rotate. When the catalyst falls onto the spiral plate 8, the spiral plate 8 will drive the catalyst to rotate in a spiral. Since the bottom end of the spiral plate 8 is staggered with the extension plate 6, the catalyst can be driven to rotate during the rotation of the spiral plate 8, and the catalyst will fall evenly between the annular chamber 44 and the reaction tube 1 in a circular trajectory. Since the annular chamber 44 is equipped with a blowhole 81 at the top, when gas is introduced, some gas will be blown out through the blowhole 81, and the blown-out gas will blow off the catalyst remaining at the top of the annular chamber 44. Furthermore, since the extension plate 6 has a long plate 64 fixed at the bottom, during the rotation of the extension plate 6, the long plate 64 will rotate along the inside of the reaction tube 1. The rotating long plate 64 will scrape the inner wall of the reaction tube 1, thereby removing the catalyst attached to the inside of the reaction tube 1 and preventing the catalyst from being attached to the inner wall of the reaction tube 1 for a long time, which would cause heat insulation. At the same time, the attached catalyst will sinter. Furthermore, as the cylinder 4 rotates, it drives the cleaning chamber 7 to rotate synchronously, which can scrape up and collect the catalyst accumulated on the surface of the distribution plate 3. At the same time, the carbon source gas in the inner ring of the cylinder 4 is introduced into the cleaning chamber 7 through the gas channel 72 and sprayed out at high speed through the nozzle 71, blowing the collected catalyst into the fluidization area, so that the catalyst re-enters the up-and-down tumbling state, ensuring that every catalyst particle can contact the carbon source gas, realizing the full-range fluidization of the catalyst in the reaction area, and further improving the contact efficiency between the carbon source gas and the catalyst. At the same time, the long plate 64 rotates synchronously with the extension plate 6 and scrapes the inner wall of the reaction tube 1, thereby timely removing the attached catalyst particles and carbon deposits, avoiding the temperature field distortion caused by the formation of a heat insulation layer on the inner wall in traditional devices, and preventing the attached catalyst from forming stubborn agglomerates due to long-term high-temperature sintering.

[0029] As one embodiment of the present invention; a circular ring 9 is provided below the distribution plate 3; The ring 9 is fixed with evenly arranged round rods 91, and the round rods 91 are initially inserted into the air hole 31 located between the cylinder 4 and the reaction tube 1. The inner ring of the circular ring 9 is fixed with a limiting plate 92, and a rectangular groove is provided in the middle of the limiting plate 92, and the rectangular rod 35 passes through the rectangular groove; A second electric push rod 93 is installed at the bottom of the horizontal plate 34; a third annular groove 94 is opened at the bottom of the ring 9, and the cross-section of the third annular groove 94 is C-shaped; a second sliding shaft 95 is fixed at the top of the second electric push rod 93, and the second sliding shaft 95 slides in the third sliding groove. Since the round rod 91 is initially inserted into the vent 31, when feeding, the vent 31 is blocked by the round rod 91, thus preventing the catalyst from falling down from the vent 31. After the gas is introduced, the second electric push rod 93 is controlled to retract, thereby pulling the ring 9 and the round rod 91 down, so that the vent 31 is no longer blocked, and the gas will then pass through the vent 31. Meanwhile, since the rectangular groove in the middle of the limiting plate 92 that fixes the ring 9 is slidably connected to the rectangular rod 35, the ring 9 will rotate through the limiting plate 92 during the rotation of the rectangular rod 35, and the third ring groove 94 at the bottom of the ring 9 will rotate along the second sliding shaft 95.

[0030] In the description of this invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the appendix. Figure 1 The orientations or positional relationships shown are for the convenience of describing the present invention and simplifying the description only, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and should not be construed as indicating or implying relative importance.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A carbon nanotube production system, characterized in that, Includes the following steps: S1: The prepared catalyst is placed into the feeding mechanism. The catalyst is introduced into the reaction tube (1) in the reactor body through the feeding pipe (12) by the feeding mechanism. The reaction tube (1) is heated and inert gas is kept flowing in. S2: When the temperature inside the reaction tube (1) reaches the appropriate reaction temperature, the catalyst expands, and the carbon source gas flows through the pores (31) of the distribution plate (3) through the catalyst, causing carbon nanotubes to grow. S3: After the catalyst reaction is completed, a black particulate product is generated. Then, the motor is controlled to stop rotating and the carbon source gas is stopped. Inert gas is continued to be introduced. After the product is cooled, the first electric push rod (36) is controlled to contract, thereby pulling the distribution plate (3) down and moving the black product and reaction components down. When the distribution plate (3), black product and reaction components move down into the auxiliary tube (2), the first electric push rod (36) is controlled to stop contracting. The servo motor is controlled to drive the lead screw (23) to rotate. The rotating lead screw (23) drives the mounting plate (21) and auxiliary tube (2) to move down as a whole. When the auxiliary tube (2) is separated from the reaction tube (1), the black product above the distribution plate (3) can be collected to obtain carbon nanotubes.

2. The carbon nanotube production system according to claim 1, characterized in that: The reactor body in step S1 includes a reaction tube (1); the bottom of the reaction tube (1) is provided with an auxiliary tube (2); the auxiliary tube (2) is installed on the mounting plate (21) at the bottom, and an air inlet pipe (22) is installed at the bottom of the mounting plate (21); The mounting plate (21) is threaded with a lead screw (23), and the lead screw (23) is connected to the servo motor at the bottom; a sealing ring is fixed to the top of the auxiliary tube (2); The reaction tube (1) is equipped with a reaction assembly; the reaction assembly includes a distribution plate (3); the distribution plate (3) has multiple rings of evenly arranged air holes (31); The distribution plate (3) has a first annular groove (32) at the bottom; a first annular plate (33) slides in the first annular groove (32); a horizontal plate (34) is fixed in the inner ring of the first annular plate (33), and a motor is fixed at the bottom of the horizontal plate (34). A rectangular rod (35) is installed on the drive shaft of the motor, and the rectangular rod (35) extends into the interior of the distribution plate (3). The first ring plate (33) is equipped with a first electric push rod (36) at the bottom, and the other side of the first electric push rod (36) is installed on the mounting plate (21); the distribution plate (3) is provided with a cylinder (4) at the top, and the outer ring surface of the cylinder (4) is provided with uniformly arranged air grooves (41); The cylinder (4) is fitted with an annular chamber (44), and the air groove (41) is located inside the annular chamber (44); the inner ring of the annular chamber (44) is provided with uniformly arranged through holes (45), and the outer ring of the annular chamber (44) is provided with uniformly arranged oblique holes (46); the inner ring of the annular chamber (44) is provided with a driving component.

3. The carbon nanotube production system according to claim 2, characterized in that: The reactor body is provided with two heating boxes (11), one of which is installed on the reactor body and the other is mounted on the other heating box (11) via a hinge; a reaction tube (1) is installed inside the heating box (11), and the reaction tube (1) is a quartz tube. The top of the reaction tube (1) is equipped with a feed pipe (12) and an exhaust pipe (13), and the feed pipe (12) is connected to an external feeding mechanism; the exhaust pipe (13) is connected to an external bag filter. The cylinder (4) is provided with a second annular groove (42) on the distribution plate (3) below it, and the cross-section of the second annular groove (42) is C-shaped; the bottom of the cylinder (4) is fixed with a first sliding shaft (43), and the first sliding shaft (43) slides in the second annular groove (42); The drive assembly includes a vertical cylinder (5); the vertical cylinder (5) is arranged in the inner ring of the annular compartment (44), and the bottom of the vertical cylinder (5) is in contact with the distribution plate (3), and the top of the vertical cylinder (5) is separated from the top of the annular compartment (44); A drive rod (51) is installed on the top of the rectangular rod (35); a first gear (52) is fixed on the drive rod (51); a flat plate (53) is fixed on the inner ring of the vertical cylinder (5); a second gear (54) rotates on the bottom of the flat plate (53), and the second gear (54) meshes with the first gear (52); The inner ring of the vertical cylinder (5) is provided with uniformly arranged tooth grooves (55), and the second gear (54) meshes with the tooth grooves (55); the inner ring of the annular chamber (44) is fixed with a driven plate (56); the other side of the driven plate (56) is arranged on the outer ring of the vertical cylinder (5); The reaction chamber is fixed with a rod (58), which is inserted into the cylinder (4).

4. The carbon nanotube production system according to claim 3, characterized in that: The annular compartment (44) has multiple extension plates (6) fixed on its outer ring; a vertical rod (61) rotates below the extension plate (6), and a striking rod (62) is fixed on the vertical rod (61); The top of the extension plate (6) has two rotating wheels (63), one of which is fixed to the upright (61), and the other is attached to the reaction tube (1).

5. The carbon nanotube production system according to claim 4, characterized in that: The outer ring of the vertical tube (5) is provided with a slide rail (57), and the driven plate (56) slides in the slide rail (57); The driven plate (56) is fixed with a push shaft (59) at the bottom, and the bottom of the push shaft (59) is circular; the vertical cylinder (5) and the annular chamber (44) are fixed with evenly arranged arc-shaped blocks (591), and the arc-shaped blocks (591) are high in the middle and low on both sides.

6. The carbon nanotube production system according to claim 3, characterized in that: A cleaning chamber (7) is provided between the cylinder (4) and the reaction tube (1), and the cross-section of the cleaning chamber (7) is triangular; uniformly arranged spray holes (71) are provided on the inclined surface at the top of the cleaning chamber (7); an air passage (72) is provided on the cylinder (4), and the air passage (72) is connected to the inner ring of the cylinder (4) and the cleaning chamber (7) respectively.

7. The carbon nanotube production system according to claim 2, characterized in that: The top of the annular chamber (44) is fixed with a rotating shaft, and a spiral plate (8) is fixed on the rotating shaft; the bottom end of the spiral plate (8) is staggered with the extension plate (6); the spiral plate (8) is in contact with the reaction tube (1).

8. The carbon nanotube production system according to claim 2, characterized in that: The top of the annular chamber (44) is provided with evenly arranged blowholes (81).

9. The carbon nanotube production system according to claim 4, characterized in that: The extension plate (6) has a long plate (64) fixed at its bottom, and the cross-section of the long plate (64) is triangular; the long plate (64) is attached to the inner ring of the reaction tube (1).

10. The carbon nanotube production system according to claim 3, characterized in that: A circular ring (9) is provided below the distribution plate (3); The ring (9) is fixed with uniformly arranged round rods (91), and the round rods (91) are initially inserted into the air hole (31) between the cylinder (4) and the reaction tube (1); The inner ring (9) is fixed with a limiting plate (92), and a rectangular groove is provided in the middle of the limiting plate (92), and a rectangular rod (35) passes through the rectangular groove; The bottom of the horizontal plate (34) is equipped with a second electric push rod (93); the bottom of the ring (9) is provided with a third ring groove (94), and the cross-section of the third ring groove (94) is C-shaped; the top of the second electric push rod (93) is fixed with a second sliding shaft (95), and the second sliding shaft (95) slides in the third sliding groove.

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