Communicating device for preparing single-walled carbon nanotubes and preparation method thereof

Abstract

The invention provides a communicating device for preparing a single-walled carbon nanotube and a preparation method of the communicating device, and relates to the technical field of preparation of single-walled carbon nanotubes. The communicating device for preparing the single-walled carbon nanotubes comprises reaction equipment, the reaction equipment comprises an initial-end reactor, a gas sampling clamp, a sucking pump and a tail-end reactor, a mixing mechanism is arranged in the initial-end reactor, the mixing mechanism is an inner-layer rotating assembly, and the gas sampling clamp is arranged in the tail-end reactor. The inner-layer rotating assembly comprises a screen cylinder coaxially rotating in the initial-end reactor, a rotating nozzle is coaxially arranged at one end of the inner side of the screen cylinder, an axis turbulent flow piece is coaxially and rotatably arranged in the rotating nozzle, a radio frequency module is coaxially and fixedly connected to one side of the rotating nozzle, and the radio frequency module is coaxially and fixedly connected to the other side of the rotating nozzle. The initial-end reactor is used for generating the carbon nanotubes, the gas sampling clamp is used for recycling the carbon nanotubes, the suction pump is used for pumping tail gas into the tail-end reactor for recycling, large-scale and continuous preparation is realized, and the rotary screen drum is used for reducing particle aggregation and deposition phenomena in the reaction process at the same time.

Description

Technical Field

[0001] This application relates to the technical field of single-walled carbon nanotube preparation. Specifically, it relates to a connecting device for preparing single-walled carbon nanotubes and a preparation method thereof. Background Art

[0002] In the prior art, due to the potential development prospect of large-scale continuous production of single-walled carbon nanotubes by chemical vapor deposition method, it is used more frequently. It is divided into two types according to the catalyst introduction method: fixed catalytic cracking method and floating catalytic cracking method.

[0003] In the floating catalytic cracking method, the catalyst is introduced into the reaction zone together with the carbon source, carrier gas, etc., and carbon nanotubes are grown through cracking, reaction. However, the carbon nanotubes will stay and block the reaction chamber, resulting in an increase in the pressure inside the chamber, and the carbon nanotubes cannot grow continuously. In addition, a large amount of waste gas is wasted in this process. Therefore, its large-scale, continuous preparation and manufacturing cost are still technical bottlenecks. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art. For this purpose, this application proposes a connecting device for preparing single-walled carbon nanotubes, including a reaction device. The reaction device includes a primary reactor, a gas sampling clamp, a suction pump, and a terminal reactor that are connected in sequence. The primary reactor is internally provided with a mixing mechanism, and the terminal reactor is internally provided with a crucible. The primary reactor is arranged in a double-layer structure. A plurality of flow disturbing members are circumferentially and uniformly arranged on the inner wall of the primary reactor, and the plurality of flow disturbing members form a meandering air flow channel; a power assembly is arranged on the primary reactor; the mixing mechanism is an inner layer rotating assembly, and the inner layer rotating assembly is coaxially arranged inside the primary reactor. The inner layer rotating assembly includes a sieve drum that rotates coaxially inside the primary reactor. One end of the inner side of the sieve drum facing the inlet of the primary reactor is coaxially provided with a rotating nozzle. The rotating nozzle is communicated with the inlet end of the primary reactor. An axial flow disturbing member is coaxially and rotatably arranged inside the rotating nozzle. A radio frequency module is coaxially and fixedly connected to the side of the rotating nozzle away from the inlet end of the primary reactor.

[0005] Preferably, the flow disturbing member includes a long partition plate and a short partition plate arranged along the axial direction of the primary reactor. The long partition plate and the short partition plate are flush with each other on the side facing the inlet end of the primary reactor, and there is a gap between the long partition plate and the short partition plate and the sieve drum.

[0006] Preferably, the power assembly includes a double-headed motor fixedly connected to the outside of the primary reactor. Output shafts are respectively key-connected to both ends of the double-headed motor. A driving wheel is key-connected to the end of the output shaft. Two driven wheels are hermetically and rotatably embedded at both ends of the primary reactor. The driven wheels are engaged with the driving wheels, and both ends of the sieve drum are hermetically and fixedly connected to the driving wheels.

[0007] Preferably, an expansion part is arranged on one side of the screen drum facing the inlet end of the initial reactor, and the expansion part is radially expanded along the direction from the inlet end to the outlet end of the initial reactor, and the remaining part of the screen drum is in a straight cylinder shape.

[0008] Preferably, a plurality of flow disturbing plates are evenly arranged on the outer circumference of the expansion part, and the plurality of flow disturbing plates do not contact the flow disturbing parts.

[0009] Preferably, a plurality of groups of flow disturbing blocks are evenly arranged on the inner circumference of the straight cylinder part of the screen drum, and each group of flow disturbing blocks is arranged in a spiral shape along the axial direction of the screen drum.

[0010] Preferably, the rotary nozzle is coaxially rotationally connected to the inlet end pipeline of the initial reactor, and the rotary nozzle is located inside the expansion part. The rotary nozzle includes an arc-shaped end cap, an arc-shaped bottom, and a plurality of first arc-shaped pieces. The plurality of first arc-shaped pieces are circumferentially and evenly fixed between the arc-shaped end cap and the arc-shaped bottom and form a plurality of arc-shaped channels. The sides of the arc-shaped end cap and the arc-shaped bottom close to each other are arranged in similar arcs, and a hole is arranged at the axis of the arc-shaped bottom, and an annular groove is arranged in the hole.

[0011] Preferably, the axis flow disturbing part includes a rotary cylinder, a plurality of second arc-shaped pieces, and an annular hoop. The rotary cylinder is rotationally installed in the hole at the axis of the arc-shaped bottom. The plurality of second arc-shaped pieces are circumferentially and evenly fixed to the inner wall of the rotary cylinder. The annular hoop is coaxially fixed to the outer wall of the rotary cylinder and is rotationally installed in the annular groove.

[0012] Preferably, the radio frequency module includes a shaft rod, a plurality of support rods, a plurality of radio frequency electrodes, and a conductive slip ring. The shaft rod is coaxially arranged inside the screen drum. The plurality of support rods are circumferentially and evenly fixed to one end of the shaft rod and are fixed to the arc-shaped bottom. The plurality of radio frequency electrodes are respectively fixed to the shaft rod and are spirally distributed on the shaft rod. The conductive slip ring is coaxially arranged at the end of the shaft rod away from the support rods.

[0013] The beneficial effects of a communication device for preparing single-walled carbon nanotubes in this application are as follows: Carbon nanotubes are generated using an initial reactor, and the carbon nanotubes are recovered using a gas sampling clamp. The tail gas is pumped into a terminal reactor using a suction pump, and the terminal reactor is used to recycle the tail gas to achieve large-scale and continuous production. A double-layer nested rotating reaction device is formed by the initial reactor and a rotating sieve drum inside, which improves the mixing uniformity of the mixture in the sieve drum and prevents the catalyst particles from settling due to gravity, affecting the production effect of carbon nanotubes. A rotating nozzle is used to make the mixture enter the initial reactor with good distribution, improving the production efficiency of carbon nanotubes. An RF module in the middle of the sieve drum forms an alternating electric field between the electrode and the grounded end of the outer initial reactor when the sieve drum rotates, exciting local plasma and strengthening the cracking of the carbon source, thereby increasing the production rate of carbon nanotubes. The rotating sieve drum simultaneously forms a product conveying effect, reducing particle agglomeration and deposition during the reaction process.

[0014] On the other hand, the present application further provides a method for preparing single-walled carbon nanotubes, comprising the following steps: S1: Feeding. Ferrocene dissolved in alcohol is fed into the preheated inlet end of the initial reactor using a peristaltic pump and mixed with a protective gas, and the gas flow rate is 0.1 - 50 L / min. S2: The mixture enters the initial reactor. The mixture enters the sieve drum from the periphery and the axis of the rotating nozzle. Under the action of the power assembly, the sieve drum rotates axially, causing the catalyst particles in the entering mixture to adhere closely to the inner wall of the sieve drum, forming a uniformly distributed "particle film" to prevent gravity settlement. The rotating nozzle rotates under the action of the mixture flow and distributes the mixture as evenly as possible in the sieve drum. S3: Initial reaction stage. During S2, the rotating sieve drum makes the heat distribution in the inner cavity of the initial reactor uniform, and the mixture is cracked in the sieve drum by heating and the growth of carbon nanotubes is promoted. S4: Second stage. The new mixture formed in S3 is pumped into the gas sampling clamp using the suction pump to collect the carbon nanotubes therein. S5: Terminal reaction stage. The tail gas filtered in S4 is transported to the terminal reactor, a gaseous carbon source is fed into the terminal reactor, and a solid catalyst is pre-placed in the terminal reactor to generate single-walled carbon nanotubes from the tail gas in the terminal reactor.

[0015] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. Description of the Drawings

[0016] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a schematic diagram of the overall structure of a connection device for preparing single-walled carbon nanotubes according to an embodiment of the present application; Figure 2 It is a schematic diagram of a partial structure of a connection device for preparing single-walled carbon nanotubes according to an embodiment of the present application Figure 1 ; Figure 3 It is a schematic diagram of a partial structure of a connection device for preparing single-walled carbon nanotubes according to an embodiment of the present application Figure 2 ; Figure 4 It is according to an embodiment of the present application Figure 3 An enlarged schematic diagram of A therein; Figure 5 It is a schematic diagram of the internal structure of the initial reactor according to an embodiment of the present application; Figure 6 It is according to an embodiment of the present application Figure 5 An enlarged schematic diagram of B therein; Figure 7 It is a schematic diagram of the structure and position of the inner layer rotating assembly according to an embodiment of the present application; Figure 8 It is a schematic diagram of a partial structure of the inner layer rotating assembly according to an embodiment of the present application; Figure 9 It is a schematic diagram of a partial structure of the sieve drum according to an embodiment of the present application; Figure 10 It is an exploded view of the structure of the rotating nozzle and the axial flow spoiler according to an embodiment of the present application; Figure 11 It is an exploded view of the structure of the axial flow spoiler according to an embodiment of the present application; Figure 12 It is a schematic diagram of the structure of the RF module according to an embodiment of the present application; Figure 13 It is a schematic diagram of the structure and position of the vibration mechanism and the self-cleaning mechanism according to an embodiment of the present application; Figure 14 It is a schematic diagram of the internal structure of the elastic support member according to an embodiment of the present application; Figure 15 It is an exploded view of a partial structure of the vibration mechanism and the self-cleaning mechanism according to an embodiment of the present application; Figure 16is according to an embodiment of the present application Figure 13 An enlarged schematic diagram of C in Figure 17 is an optical photograph of single-walled carbon nanotubes prepared by floating catalytic pyrolysis according to an embodiment of the present application; Figure 18 is a scanning electron microscope image of single-walled carbon nanotubes prepared by floating catalytic pyrolysis according to an embodiment of the present application; Figure 19 is a Raman spectrum of single-walled carbon nanotubes prepared by floating catalytic pyrolysis according to an embodiment of the present application; Figure 20 is an optical photograph of single-walled carbon nanotubes prepared by fixed-bed catalytic pyrolysis according to an embodiment of the present application; Figure 21 is a scanning electron microscope image of single-walled carbon nanotubes prepared by fixed-bed catalytic pyrolysis according to an embodiment of the present application; Figure 22 is a Raman spectrum of single-walled carbon nanotubes prepared by fixed-bed catalytic pyrolysis according to an embodiment of the present application.

[0018] Icon: 1. Reaction equipment; 11. Initial reactor; 111. Input pipe; 112. Inlet for protective gas; 113. Liquid inlet; 114. Heating belt; 115. Pressure gauge; 116. Pressure relief valve; 117. Vacuum layer; 118. Installation cavity; 119. Heating ring; 12. Gas sampling clamp; 121. Pressure sensing device; 13. Air pump; 14. Terminal reactor; 141. Inlet for carbon source gas; 142. Crucible; 2. Turbulence element; 21. Long partition; 22. Short partition; 3. Power assembly; 31. Double-headed motor; 32. Output shaft; 33. Driving wheel; 34. Driven wheel; 4. Inner rotating assembly; 41. Sieve drum; 411. Expansion part; 412. Turbulence plate; 413. Turbulence block; 42. Rotating nozzle; 421. Arc-shaped end cap; 422. Arc-shaped bottom; 423. First arc-shaped piece; 424. Annular groove; 43. Axial turbulence element; 431. Rotating cylinder; 432. Second arc-shaped piece; 433. Annular hoop; 44. Radio frequency module; 441. Shaft rod; 442. Support rod; 443. Radio frequency electrode; 444. Conductive slip ring; 5. Vibration mechanism; 51. Elastic support; 511. End support cylinder; 512. Guide rod; 513. Sealing plug; 52. Snap ring; 53. Vibration motor; 6. Self-cleaning mechanism; 61. Electromagnet; 62. Cleaning component; 621. Guide post; 622. Chute; 623. Permanent magnet; 624. Scraper. Detailed implementation manners

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0020] Example 1, as Figures 1-16 shown, a connection device for preparing single-walled carbon nanotubes according to an embodiment of this application includes a reaction device 1. The reaction device 1 includes a primary reactor 11, a gas sampling clamp 12, a suction pump 13, and a terminal reactor 14 that are connected in sequence. The primary reactor 11 is internally provided with a mixing mechanism, and the terminal reactor 14 is internally provided with a crucible 142.

[0021] Among them, as Figures 1-6 shown, an input pipe 111 is connected to the inlet end of the primary reactor 11. A protective gas inlet 112 is connected to the input pipe 111. The protective gas inlet 112 is connected to a liquid inlet 113. A heating belt 114 is sleeved on the end of the input pipe 111 close to the primary reactor 11 for preheating the mixture. The outlet end of the primary reactor 11 is connected to two parallel gas sampling clamps 12. A pressure gauge 115 and a pressure relief valve 116 are provided on the pipeline between the outlet end of the primary reactor 11 and the two parallel gas sampling clamps 12 to facilitate maintaining the dynamic balance of the internal pressure of the primary reactor 11 through the pressure relief valve 116.

[0022] In a specific embodiment of this application, as Figure 4 shown, the primary reactor 11 is arranged in a double-layer structure. The outer layer is a vacuum layer 117, which plays an effect of heat insulation to prevent heat energy from escaping. The inner layer is an installation cavity 118, in which a plurality of heating rings 119 are arranged to provide the heat energy required for the reaction.

[0023] Specifically, pressure sensing devices 121 are respectively arranged on both sides of the two parallel gas sampling clamps 12 (which are gas filtering devices). So that after the carbon nanotubes are continuously blown out of the primary reactor 11 with the gas, they are deposited in the gas filtering device of the first collection channel. When a certain pressure is generated by the deposition, this channel automatically closes, and at the same time, the other channel automatically opens to start a new round of collection, realizing the continuous collection of carbon nanotubes without stopping the reaction.

[0024] A plurality of flow disturbing members 2 are circumferentially and uniformly arranged on the inner wall of the primary reactor 11. The plurality of flow disturbing members 2 form a tortuous air flow channel. Specifically, as Figures 5-7As shown, the spoiler 2 includes a long partition 21 and a short partition 22 arranged along the axial direction of the primary reactor 11. The long partition 21 and the short partition 22 are arranged flush with each other on the side facing the inlet end of the primary reactor 11. There is a gap between the long partition 21 and the short partition 22 and the sieve drum 41. It should be noted that the side of the long partition 21 and the short partition 22 facing the inlet end of the primary reactor 11 does not abut the end facing the primary reactor 11. Figure 5 As shown, it can be understood that a distance is left between the spoiler 2 and one end of the interior of the initial reactor 11 to facilitate the circulation of the airflow.

[0025] The initial reactor 11 is provided with a power assembly 3, such as Figure 3 and Figure 7 As shown, the power assembly 3 includes a double-headed motor 31 fixedly connected to the outside of the primary reactor 11, and the two ends of the double-headed motor 31 are keyed to the output shaft 32 respectively, and the end of the output shaft 32 is keyed to the driving wheel 33. Two driven wheels 34 are sealed and rotatably embedded at both ends of the primary reactor 11, and the driven wheel 34 is engaged with the driving wheel 33. The two ends of the screen drum 41 are sealed and fixed to the driving wheel 33. It can be understood that by starting the double-headed motor 31, the screen drum 41 can be driven to rotate inside the primary reactor 11.

[0026] like Figures 7-12 As shown, the mixing mechanism is an inner rotating assembly 4, which is coaxially arranged inside the primary reactor 11. The inner rotating assembly 4 includes a sieve drum 41 that coaxially rotates inside the primary reactor 11. A rotating nozzle 42 is coaxially arranged on the inner side of the sieve drum 41 facing the inlet of the primary reactor 11. The rotating nozzle 42 is connected to the inlet end of the primary reactor 11. An axial spoiler 43 is coaxially arranged inside the rotating nozzle 42. A radio frequency module 44 is coaxially fixed to the side of the rotating nozzle 42 away from the inlet end of the primary reactor 11. Specifically, an expansion portion 411 is provided on the side of the sieve drum 41 facing the inlet end of the primary reactor 11. The expansion portion 411 is radially expanded from the inlet end to the outlet end of the primary reactor 11, and the remaining portion of the sieve drum 41 is straight cylindrical.

[0027] Furthermore, a plurality of spoilers 412 are evenly arranged on the outer circumference of the expansion portion 411, and the plurality of spoilers 412 do not contact the spoiler 2. It can be seen that when the sieve drum 41 rotates, it will drive the plurality of spoilers 412 thereon to rotate synchronously, thereby forming an airflow between the initial reactor 11 and the sieve drum 41. The airflow circulates through the circuitous channel formed by the long partition 21 and the short partition 22, so that the heat generated by the heating ring 119 can be evenly distributed on the inner side of the initial reactor 11, thereby improving the generation efficiency of carbon nanotubes.

[0028] It should be noted that, Figure 8 andFigure 9 As shown, multiple groups of spoiler blocks 413 are circumferentially and evenly arranged on the inner side of the straight cylinder part of the sieve drum 41, and each group of spoiler blocks 413 is arranged in a spiral shape along the axial direction of the sieve drum 41.

[0029] It can be understood that when the sieve drum 41 rotates, it will synchronously drive multiple groups of spoiler blocks 413 to rotate in the same direction. In this way, the multiple groups of spoiler blocks 413 arranged in a spiral shape will first play a conveying effect, avoiding the retention of the generated carbon nanotubes inside the sieve drum 41, which may cause the blockage of the reaction chamber. At the same time, the rotating spoiler blocks 413 will also play a good mixing effect, promoting the mixing of the mixture, improving the generation efficiency of carbon nanotubes, precisely controlling the residence time of the catalyst in the high-temperature zone (by adjusting the rotation speed), and realizing continuous production.

[0030] Furthermore, it can be understood that in the specific embodiment of the present application, the rotating sieve drum 41 can make the catalyst particles in the mixture closely adhere to the inner wall of the sieve drum 41, forming a uniformly distributed "particle film", avoiding the gravitational settlement of the catalyst particles and the generated carbon nanotubes.

[0031] As Figure 7 , Figure 8 , Figure 10 and Figure 11 shown, the rotary nozzle 42 is coaxially and rotationally connected to the inlet pipe (input pipe 111) of the initial reactor 11, and the rotary nozzle 42 is located inside the expansion part 411. The rotary nozzle 42 includes an arc-shaped end cap 421, an arc-shaped bottom 422, and multiple first arc-shaped pieces 423. The multiple first arc-shaped pieces 423 are circumferentially and evenly fixed between the arc-shaped end cap 421 and the arc-shaped bottom 422 and form multiple arc-shaped channels. Among them, the sides of the arc-shaped end cap 421 and the arc-shaped bottom 422 that are close to each other are arranged in a similar arc shape, and a hole is provided at the axis of the arc-shaped bottom 422, and an annular groove 424 is provided in the hole.

[0032] Specifically, the multiple arc-shaped channels formed inside the rotary nozzle 42 change from an axial distribution to a radial distribution along the flow direction of the mixture. Therefore, part of the mixture will flow from the circumferential side of the rotary nozzle 42 towards the inner wall direction of the expansion part 411 after entering the arc-shaped channel, and then flow into the straight cylinder section of the sieve drum 41 under the inclination effect of the inner wall of the expansion part 411.

[0033] Among them, the axial spoiler member 43 includes a rotating cylinder 431, multiple second arc-shaped pieces 432, and an annular hoop 433. The rotating cylinder 431 is rotationally fitted into the hole at the axis of the arc-shaped bottom 422. The multiple second arc-shaped pieces 432 are circumferentially and evenly fixed to the inner wall of the rotating cylinder 431. The annular hoop 433 is coaxially fixed to the outer wall of the rotating cylinder 431 and is rotationally fitted into the annular groove 424.

[0034] It can be understood that when the mixture passes through the rotary nozzle 42, a part of it will directly pass through from the axial spoiler 43. Further, it can be understood that when the mixture flows through the multiple arc-shaped channels formed inside the rotary nozzle 42 and when the mixture flows through the rotary cylinder 431, forces will be exerted on the multiple first arc-shaped pieces 423 and the second arc-shaped pieces 432, and the rotary nozzle 42 and the axial spoiler 43 will be forced to rotate in a complementary interference manner. Thus, it can be understood that the mixture will form a better mixture under the action of the rotating rotary nozzle 42 and the axial spoiler 43, and a better uniform distribution effect will be formed inside the sieve drum 41.

[0035] As Figure 12 shown, the radio frequency module 44 includes a shaft rod 441, multiple support rods 442, multiple radio frequency electrodes 443, and a conductive slip ring 444. The shaft rod 441 is coaxially arranged inside the sieve drum 41. The multiple support rods 442 are circumferentially and uniformly fixed to one end of the shaft rod 441 and are fixed to the arc-shaped bottom 422. The multiple radio frequency electrodes 443 are respectively fixed to the shaft rod 441 and are spirally distributed on the shaft rod 441. The conductive slip ring 444 is coaxially arranged at the end of the shaft rod 441 far from the support rods 442.

[0036] It can be understood that when the multiple radio frequency electrodes 443 rotate, an alternating electric field can be formed with the grounding end of the outer-layer initial reactor 11, exciting local plasma. The temperature in the plasma region can reach 3000K, which helps to strengthen the cracking of the carbon source and at the same time etch amorphous carbon impurities.

[0037] It should be noted that in the specific embodiments of the present application, the reactor is a quartz tube or a corundum tube (preferably a corundum tube). The size of the used quartz tube is 40 - 300 mm (preferably 80 mm), and the length is 500 - 3000 mm (preferably 1200 mm); The protective gas is nitrogen or a mixed gas of argon and hydrogen (preferably an argon-hydrogen mixed gas), and the proportion of hydrogen is 10 - 100% (preferably 50%); The reaction solution is a mixed solution of hydrocarbons composed of carbon and hydrogen elements and alcohols and ketone compounds composed of carbon, hydrogen, and oxygen elements in which ferrocene and thiophene are dissolved (preferably ethanol); The input tube 111 is preheated to 80 - 150 °C (preferably 140 °C) by the heating belt 114 to help the reaction solution vaporize; The pressure inside the initial reactor 11 is maintained at a negative pressure by adjusting the pressure relief valve 116; The filter paper contained in the gas sampling clamp 12 has a pore size of 0.1 - 1 μm (preferably 0.1 μm); The gaseous carbon source is a hydrocarbon chemical compound composed of carbon and hydrogen elements (preferably acetylene).

[0038] The following describes the usage process of a connection device for preparing single-walled carbon nanotubes according to an embodiment of the present application with reference to the accompanying drawings: When in use, the reaction is carried out in the initial reactor 11 by the floating catalyst pyrolysis method. The temperature is raised to 800 - 1500 °C (preferably 1100 °C) through the heating ring 119. The protective gas is a mixed gas of argon and hydrogen (hydrogen accounts for 50%). Ethanol serves as both the carbon source and the solvent. The concentration of ferrocene is 0.1 - 2 g / ml. The reaction solution is injected into the liquid inlet 113 at a feeding speed of 0.1 - 1000 μl / min using a liquid supply pump. Ferrocene is fed into the preheated input pipe 111 at a flow rate of 0.1 - 1000 μl / min using a peristaltic pump and mixed with the protective gas. The mixture enters the initial reactor 11 through the rotating nozzle 42 and the axial flow spoiler 43 and forms a uniform distribution. Under the action of the rotating sieve drum 41, better mixing and uniform distribution are further formed. The mixture undergoes a high-temperature catalytic cracking reaction to grow carbon nanotubes. The carbon nanotubes are continuously blown out of the reactor and transported in two parallel gas sampling clips 12 under the action of the gas and the multiple flow spoilers 413 in the rotating sieve drum 41. Among them, under the action of the pressure sensing device 121, one of the two parallel gas sampling clips 12 is opened. The carbon nanotubes are deposited in the gas sampling clip 12 of the first collection channel along with the gas. When a certain pressure is generated by the deposition, this channel automatically closes, and at the same time, the other channel automatically opens to start a new round of collection. In this way, the continuous collection of carbon nanotubes is achieved without stopping the reaction. The tail gas of the floating catalyst pyrolysis method is directly introduced into the fixed catalyst pyrolysis method (the terminal reactor 14) by the air extraction pump 13 for continued preparation of single-walled carbon nanotubes. It should be noted here that, as Figures 1-3 shown, a carbon source gas inlet 141 is connected to the front end of the terminal reactor 14. A crucible 142 is arranged inside the terminal reactor 14. A solid catalyst is pre-placed in the crucible 142. The solid catalyst is an iron-molybdenum alloy supported on an alumina or magnesia matrix (preferably a magnesia matrix). The growth temperature in the terminal reactor 14 is 600 - 1000 °C. The carbon source used is acetylene. The tail gas generates single-walled carbon nanotubes in the terminal reactor 14. In this way, the large-scale and continuous preparation of carbon nanotubes is achieved.

[0039] Furthermore, it should be noted that, as Figure 17 shown is an optical photograph of single-walled carbon nanotubes collected by the floating catalyst pyrolysis method, presenting a black film shape with uniform color; Figure 18 shown is a scanning electron microscope image, with an overall uniform and dense distribution and an aspect ratio > 1000; Figure 19 is a Raman spectrum. The spectrum shows obvious radial breathing characteristic peaks of single-walled carbon nanotubes and a very high degree of graphitization (IG / ID = 139); Figure 20 shown is a physical picture of single-walled carbon nanotubes prepared by the chemical vapor deposition method, presenting a black powder shape;Figure 21 This is a scanning electron microscope image, which is also uniformly dense as a whole; Figure 22 This is a Raman spectrum, which also shows the radial breathing characteristic peak of single-walled carbon nanotubes. Its IG / ID = 15, indicating a high degree of graphitization; it proves that the device has successfully connected the floating catalytic cracking method and the fixed catalytic cracking method, and has high reference value for the efficient, low-cost and large-scale preparation of high-quality single-walled carbon nanotubes.

[0040] In Example 2, in the related art, although the rotating sieve drum 41 helps to form a uniformly distributed "particle film" on its inner wall to avoid gravitational sedimentation, the generated carbon nanotubes will more or less cause blockage of the sieve mesh of the sieve drum 41 itself. This will affect the penetration of heat into the interior of the sieve drum 41 and cause the internal heat distribution of the sieve drum 41 to be affected. Secondly, although there are multiple sets of turbulator blocks 413 spirally distributed inside the rotating sieve drum 41, which can convey the particles to a certain extent, they cannot break the cohesive force between the particles, and the generated particles or catalyst particles are prone to agglomerate due to the cohesive force and then cause the occurrence of gravitational sedimentation.

[0041] According to some embodiments of the present application, as Figures 13-15 shown, a vibration mechanism 5 is further provided on the initial reactor 11. The vibration mechanism 5 includes a plurality of elastic support members 51 symmetrically arranged at both ends of the initial reactor 11. The plurality of elastic support members 51 symmetrically arranged at both ends of the initial reactor 11 are respectively annularly distributed, and clamping rings 52 are fixedly connected to the inner sides of the annularly distributed plurality of elastic support members 51. A plurality of vibration motors 53 are uniformly fixedly connected to the outer wall of the initial reactor 11.

[0042] Furthermore, the elastic support member 51 includes two end support cylinders 511 symmetrically arranged. A guide rod 512 is coaxially inserted between the two end support cylinders 511. Sealing plugs 513 are symmetrically fixedly connected to both ends of the guide rod 512. The sealing plugs 513 are respectively in sealed sliding fit with the corresponding end support cylinders 511.

[0043] Among them, the end support cylinder 511 is filled with compressed gas, and the compressed gas is located on the side of the sealing plug 513 away from the guide rod 512.

[0044] It should be noted that the vibration motor 53 has a high-frequency vibration function, and the vibration frequency transmitted to the sieve drum 41 is preferably 50–200 Hz, and the amplitude is 0.1–1 mm.

[0045] It is further noted that the clamping ring 52 is rotatably sleeved on the sieve drum 41.

[0046] Thus, it can be understood that after multiple vibration motors 53 are started, the vibration sensation will be transmitted to multiple elastic supports 51 at both ends through the housing of the initial reactor 11. At this time, frequent telescopic changes will occur between the two end support cylinders 511 and the guide rod 512. The compressed gas built in the end support cylinder 511 will endow the two end support cylinders 511 and the guide rod 512 with functions of reset and buffering. In this way, after the vibration sensation decays to a certain extent, it is transmitted to the sieve drum 41, causing the sieve drum 41 to have radial micro-vibrations during rotation. In this way, the particles in the sieve drum 41 will first reduce the blockage of the sieve mesh under the action of vibration. Secondly, the vibration will destroy the agglomeration force between the particles, avoiding the occurrence of gravity sedimentation phenomenon easily caused by the agglomeration of the generated particles or catalyst particles due to the agglomeration force. At the same time, the turbulent diffusion of the gas-solid interface is enhanced. At the same time, the rotating magnetic field formed by the rotating radio frequency module 44 cooperates to make the catalyst particles generate a composite motion of "radial oscillation + circumferential rotation", improving the contact area between the gas phase and the solid phase.

[0047] Embodiment 3. In the related art, although the vibration method can reduce the blockage of the sieve mesh of the sieve drum 41 to a certain extent, during the continuous preparation process, with the passage of time, the blockage of the sieve mesh of the sieve drum 41 will more or less exist. Therefore, it will affect the generation effect and efficiency of carbon nanotubes during the continuous processing process.

[0048] According to some embodiments of the present application, as Figure 13 、 Figure 15 and Figure 16 shown, a self-cleaning mechanism 6 is further provided on the initial reactor 11. The self-cleaning mechanism 6 includes an electromagnet 61 fixedly connected to the outside of the initial reactor 11, and a cleaning component 62 provided inside the initial reactor 11.

[0049] Among them, the cleaning component 62 includes two guide columns 621 symmetrically fixedly connected to the inner wall of the initial reactor 11. A chute 622 is provided on the guide column 621. A permanent magnet 623 is slidably connected in the chute 622. The permanent magnet 623 and the electromagnet 61 are distributed along the radial direction of the initial reactor 11. A scraper 624 is fixedly connected to the side of the permanent magnet 623 facing the axis of the initial reactor 11.

[0050] Furthermore, the guide column 621, the permanent magnet 623 and the scraper 624 are located between one of the flow disturbing members 2.

[0051] Thus, it can be understood that by passing an electric current through the electromagnet 61 to form a magnetic field, when the inner side of the electromagnet 61 and the outer side of the permanent magnet 623 are of the same pole, the two will repel each other, and then the permanent magnet 623 will drive the scraper 624 to approach the outer wall of the sieve drum 41 along the chute 622. In this way, during the rotation of the sieve drum 41, the scraper 624 will clean the sieve mesh on it. On the contrary, when the inner side of the electromagnet 61 and the outer side of the permanent magnet 623 are of opposite poles, the two will attract each other, that is, at this time, the permanent magnet 623 drives the scraper 624 to displace along the chute 622 to the side away from the outer wall of the sieve drum 41. With this design, the electromagnetic device can periodically (every 5 - 30 minutes) extend towards the sieve drum 41 to scrape off the carbon nanotubes or tar deposited in the pores of the sieve mesh, and the debris can be discharged with the air flow to achieve dynamic cleaning, prevent the sieve mesh from being blocked, and maintain long-term stable operation.

[0052] On the other hand, the embodiment of the present application further provides a preparation method for single-walled carbon nanotubes, including the following steps: S1: Feeding. Use a peristaltic pump to supply ferrocene dissolved in alcohol to the preheated inlet end of the primary reactor 11 and mix it with the protective gas, and the gas flow rate is 0.1 - 50 L / min; S2: The mixture enters the primary reactor 11. The mixture enters the sieve drum 41 from the circumferential side and the axis of the rotary nozzle 42. Under the action of the power assembly 3, the sieve drum 41 rotates axially, so that the catalyst particles in the entering mixture adhere to the inner wall of the sieve drum 41, forming a uniformly distributed "particle film" to avoid gravitational sedimentation. Among them, the rotary nozzle 42 rotates under the action of the mixture flow and distributes the mixture as evenly as possible in the sieve drum 41; S3: Primary reaction stage. During the process of S2, the rotating sieve drum 41 makes the heat distribution in the inner cavity of the primary reactor 11 uniform, and through heating, the mixture in the sieve drum 41 is cracked and the growth of carbon nanotubes is promoted; S4: Second stage. The new mixture formed in S3 is pumped into the gas sampling clamp 12 by the air extraction pump 13 to collect the carbon nanotubes in it; S5: Terminal reaction stage. The tail gas filtered in S4 is transported to the terminal reactor 14, a gaseous carbon source is supplied to the terminal reactor 14, and a solid catalyst is pre-placed in the terminal reactor 14, so that the tail gas generates single-walled carbon nanotubes in the terminal reactor 14.

[0053] It should be noted that the specific model specifications of the gas sampling clamp 12, the air extraction pump 13, the pressure gauge 115, the pressure relief valve 116, the heating ring 119, the pressure sensing device 121, the crucible 142, the double-headed motor 31, the sieve drum 41, the radio frequency electrode 443, the conductive slip ring 444, the vibration motor 53, the electromagnet 61, and the permanent magnet 623 need to be selected according to the actual specifications of the device, etc. The specific selection calculation method adopts the existing technology in the field, so it will not be elaborated in detail.

[0054] The above is only the preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A connecting device for preparing single-walled carbon nanotubes, comprising a reaction device (1), wherein the reaction device (1) includes a primary reactor (11), a gas sampling clamp (12), a suction pump (13), and a terminal reactor (14) that are connected in sequence. The primary reactor (11) is internally provided with a mixing mechanism, and the terminal reactor (14) is internally provided with a crucible (142), and is characterized in that: The primary reactor (11) is arranged in a double-layer structure. A plurality of flow disturbing members (2) are circumferentially and uniformly arranged on the inner wall of the primary reactor (11), and the plurality of flow disturbing members (2) form a meandering air flow channel; A power assembly (3) is arranged on the primary reactor (11); The mixing mechanism is an inner-layer rotating assembly (4). The inner-layer rotating assembly (4) is coaxially arranged inside the primary reactor (11). The inner-layer rotating assembly (4) includes a sieve drum (41) that rotates coaxially inside the primary reactor (11). One end of the inner side of the sieve drum (41) facing the inlet of the primary reactor (11) is coaxially provided with a rotating nozzle (42). The rotating nozzle (42) is communicated with the inlet end of the primary reactor (11). An axial flow disturbing member (43) is coaxially and rotatably arranged inside the rotating nozzle (42). A radio frequency module (44) is coaxially and fixedly connected to the side of the rotating nozzle (42) away from the inlet end of the primary reactor (11).

2. The connecting device for preparing single-walled carbon nanotubes according to claim 1, characterized in that: The flow disturbing member (2) includes a long partition plate (21) and a short partition plate (22) arranged along the axial direction of the primary reactor (11). The long partition plate (21) and the short partition plate (22) are flush on the side facing the inlet end of the primary reactor (11), and there is a gap between the long partition plate (21), the short partition plate (22) and the sieve drum (41).

3. The connecting device for preparing single-walled carbon nanotubes according to claim 1, characterized in that: The power assembly (3) includes a double-headed motor (31) fixedly connected to the outside of the primary reactor (11). Output shafts (32) are respectively key-connected to both ends of the double-headed motor (31). A driving wheel (33) is key-connected to the end of the output shaft (32). Two driven wheels (34) are hermetically and rotatably embedded at both ends of the primary reactor (11). The driven wheels (34) are meshed with the driving wheel (33), and both ends of the sieve drum (41) are hermetically and fixedly connected to the driving wheel (33).

4. The communication device for preparing single-walled carbon nanotubes according to claim 1, characterized in that: One side of the sieve drum (41) facing the inlet end of the primary reactor (11) is provided with an expansion part (411). The expansion part (411) is radially expanded along the direction from the inlet end to the outlet end of the primary reactor (11), and the remaining part of the sieve drum (41) is in a straight cylinder shape.

5. The connecting device for preparing single-walled carbon nanotubes according to claim 4, characterized in that: A plurality of flow disturbing plates (412) are circumferentially and uniformly arranged on the outer side of the expansion part (411), and the plurality of flow disturbing plates (412) do not contact the flow disturbing members (2).

6. The connecting device for preparing single-walled carbon nanotubes according to claim 4, characterized in that: A plurality of groups of flow disturbing blocks (413) are circumferentially and uniformly arranged on the inner side of the straight cylinder part of the sieve drum (41). Each group of flow disturbing blocks (413) is arranged in a spiral shape along the axial direction of the sieve drum (41).

7. The connecting device for preparing single-walled carbon nanotubes according to claim 4, characterized in that: The rotary nozzle (42) is coaxially and rotationally connected to the inlet pipe of the initial reactor (11), and the rotary nozzle (42) is located inside the expansion part (411). The rotary nozzle (42) includes an arc-shaped end cap (421), an arc-shaped bottom (422), and a plurality of first arc-shaped sheets (423). The plurality of first arc-shaped sheets (423) are circumferentially and uniformly fixed between the arc-shaped end cap (421) and the arc-shaped bottom (422) to form a plurality of arc-shaped channels. The sides of the arc-shaped end cap (421) and the arc-shaped bottom (422) close to each other are arranged in a similar arc shape, and a hole is provided at the axis of the arc-shaped bottom (422), and an annular groove (424) is provided in the hole.

8. The connecting device for preparing single-walled carbon nanotubes according to claim 7, wherein: The axis flow disturbing member (43) includes a rotating cylinder (431), a plurality of second arc-shaped sheets (432), and an annular hoop (433). The rotating cylinder (431) is rotationally fitted into the hole at the axis of the arc-shaped bottom (422). The plurality of second arc-shaped sheets (432) are circumferentially and uniformly fixed to the inner wall of the rotating cylinder (431), and the annular hoop (433) is coaxially fixed to the outer wall of the rotating cylinder (431) and rotationally fitted into the annular groove (424).

9. The connecting device for preparing single-walled carbon nanotubes according to claim 8, wherein: The radio frequency module (44) includes a shaft rod (441), a plurality of support rods (442), a plurality of radio frequency electrodes (443), and a conductive slip ring (444). The shaft rod (441) is coaxially arranged inside the sieve drum (41). The plurality of support rods (442) are circumferentially and uniformly fixed to one end of the shaft rod (441) and fixed to the arc-shaped bottom (422). The plurality of radio frequency electrodes (443) are respectively fixed to the shaft rod (441) and are spirally distributed on the shaft rod (441). The conductive slip ring (444) is coaxially arranged at the end of the shaft rod (441) away from the support rods (442).

10. A method for preparing single-walled carbon nanotubes, characterized in that: Using a connecting device for preparing single-walled carbon nanotubes according to any one of claims 1-9, comprising the following steps: S1: Feeding. Use a peristaltic pump to supply ferrocene dissolved in alcohol to the preheated inlet of the initial reactor (11) and mix it with the protective gas, and the gas flow rate is 0.1-50 L / min. S2: The mixture enters the initial reactor (11). The mixture enters the sieve drum (41) from the circumferential side and the axis of the rotary nozzle (42). Under the action of the power assembly (3), the sieve drum (41) rotates axially, so that the catalyst particles in the entering mixture are close to the inner wall of the sieve drum (41) to form a uniformly distributed "particle film" to avoid gravitational settlement. The rotary nozzle (42) rotates under the action of the mixture flow and distributes the mixture as evenly as possible in the sieve drum (41). S3: Initial reaction stage. During S2, the rotating sieve drum (41) makes the heat distribution in the inner cavity of the initial reactor (11) uniform, and the mixture is pyrolyzed in the sieve drum (41) by heating and the growth of carbon nanotubes is promoted. S4: In the second stage, the new mixture formed in S3 is pumped into the gas sampling clamp (12) by the air extraction pump (13) to collect the carbon nanotubes therein; S5: In the terminal reaction stage, the tail gas filtered in S4 is transported to the terminal reactor (14), a gaseous carbon source is fed into the terminal reactor (14), and a solid catalyst is pre-placed in the terminal reactor (14) so that the tail gas generates single-walled carbon nanotubes in the terminal reactor (14).

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