Carbon nanotube production method capable of uniformly controlling temperature

Abstract

The invention discloses a carbon nanotube production method with uniform temperature control, and particularly relates to the technical field of carbon nanotube production, which comprises the following steps: catalyst preparation, catalyst powder feeding, carbon-containing gas feeding, reaction heating, auxiliary gas blowing, gas input into a gas blowing frame, and air flow blowing out of impact air holes. Airflow blown out of the impact air holes is blown to the inner wall of the soaking reaction container and forms reflection airflow on the inner wall of the soaking reaction container, and growth, cooling and collection of the carbon nanotubes are facilitated. According to the invention, a plurality of groups of reflective gas flows can be formed on the inner wall of the soaking reaction container, so that the probability that catalyst particles are attached to and attached to the inner wall of the soaking reaction container is reduced, and the catalyst particles are prevented from being attached to the inner wall of the soaking reaction container for a long time to influence the contact of the catalyst particles with carbon-containing gas and the reaction of carbon nanotubes; the relative purity of the produced carbon nano tube is further improved, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon nanotube production, and more specifically, to a method for producing carbon nanotubes with uniform temperature control. Background Art

[0002] As a one-dimensional nanomaterial, carbon nanotubes are lightweight and have a perfect hexagonal structure connection, with many extraordinary mechanical, electrical, and chemical properties. In recent years, with the in-depth research on carbon nanotubes and nanomaterials, their broad application prospects have been continuously demonstrated.

[0003] The main methods for preparing carbon nanotubes include arc discharge method, laser ablation method, chemical vapor deposition method, etc. Among them, the chemical vapor deposition method is the preferred method for growing carbon nanotube arrays due to its good stability and low cost. Its basic principle is mainly to use catalyst particles (such as metals like iron, cobalt, nickel, etc.) as the substrate, and introduce gases containing carbon sources (such as hydrocarbon gases like methane, acetylene, etc.) and carrier gases (such as hydrogen or inert gases) into the reaction chamber. These gases decompose under heating conditions, releasing active carbon atoms. The catalyst particles serve as nucleation sites. In a high-temperature environment (usually between 600°C and 900°C), the catalyst surface adsorbs and activates the carbon-containing gas molecules, causing them to undergo cracking reactions to generate carbon atoms. During this process, hydrogen can act as a reducing agent to help remove the oxides on the catalyst surface and improve the catalyst activity. The activated carbon atoms diffuse on the surface of the catalyst particles and deposit at their edges to form carbon nanotubes.

[0004] The chemical vapor deposition method for preparing carbon nanotubes mainly requires the use of a reaction vessel, a heating system, and a gas path system. The reaction vessel is the place where chemical reactions occur, generally a sealed cavity that can withstand a certain temperature and pressure. During the CVD process, the reaction chamber needs to provide a controllable environment to promote the decomposition of precursor gases and the growth of carbon nanotubes. The heating system is used to reach the required reaction temperature inside the reaction vessel, and different forms such as resistance heating, induction heating, or infrared heating can be used. The heating system can ensure that the substrate surface reaches a sufficient temperature to activate surface atoms and promote chemical reactions. The gas path system is responsible for precisely delivering various gases (such as carrier gases, carbon source gases, reduction gases, etc.) into the reaction chamber and maintaining an appropriate flow ratio.

[0005] Among them, in the industrial production process of carbon nanotubes, particulate catalysts need to be used, that is, a corresponding amount of catalyst powder is put into the reaction vessel, and it reacts with the gas containing the carbon source in the reaction vessel. At the same time, with the help of the airflow, the catalyst powder is fully distributed in the reaction vessel and undergoes sufficient reaction to obtain a relatively large amount of carbon nanotube material.

[0006] However, for production processes with a relatively large demand for production volume, the amount of catalyst powder input is also relatively larger. Under the action of the gas flow in the reaction vessel during input, some catalyst particles will move to the inner wall of the vessel and form a fit. The surface area of this part of the catalyst particles exposed is reduced due to the shielding of the inner wall of the reaction vessel, thereby relatively reducing the contact rate with the carbon-containing gas source. As a result, the reaction of this part of the catalyst particles with carbon atoms is not sufficient, affecting the actual purity of the produced carbon nanotubes, increasing the operation amount of the purification process, and raising the production cost. Summary of the Invention

[0007] A method for producing carbon nanotubes with uniform temperature control provided by the present invention aims to solve the following problem: in existing production processes with a relatively large demand for production volume, the input catalyst powder particles will move to the inner wall of the vessel, relatively reducing their contact rate with the carbon-containing gas source. As a result, the reaction of this part of the catalyst particles with carbon atoms is not sufficient, affecting the actual purity of the produced carbon nanotubes.

[0008] To achieve the above object, the present invention provides the following technical solution: A method for producing carbon nanotubes with uniform temperature control, comprising the following steps: Step 1, catalyst preparation: Select a corresponding catalyst material and prepare it into granular catalyst powder for use. Step 2, putting the catalyst powder: Mix the catalyst powder into the carrier gas and introduce the carrier gas from the feeding assembly into the internal space of the isothermal reaction vessel. Step 3, introducing the carbon-containing gas: Introduce the carbon-containing gas into the isothermal reaction vessel through the air inlet to form an impact gas flow of the carbon-containing gas and the carrier gas containing the catalyst powder. Step 4, reaction heating: Heat the internal space of the isothermal reaction vessel through the heating assembly to the reaction temperature. Step 5, auxiliary blowing: Input gas into the blowing rack to make the impact air holes blow out gas flow, and the gas flow blown out by the impact air holes blows towards the inner wall of the isothermal reaction vessel to form a reflected gas flow on the inner wall of the isothermal reaction vessel. Step 6, carbon nanotube growth: Maintain the above conditions until the carbon nanotubes continue to grow until the required amount is reached. Step 7, cooling and collection: After the growth process is completed, turn off the heating assembly and wait for the system to cool naturally. Then, open the closed structure of the discharge port and take out the product containing carbon nanotubes.

[0009] In a preferred embodiment, an air inlet and a discharge port are provided at the bottom of the isothermal reaction vessel in Step 2. An exhaust port and a feeding assembly are provided at the top of the isothermal reaction vessel. The feeding assembly is provided at the top of the isothermal reaction vessel and includes a feeding pipe and a downward extension pipe, and the downward extension pipe extends into the internal space of the isothermal reaction vessel. An auxiliary air blowing assembly is also arranged inside the soaking reaction vessel. The auxiliary air blowing assembly includes a blowing frame which is arranged inside the soaking reaction vessel close to the inner wall of the soaking reaction vessel. Impact air holes are arranged on the blowing frame. The blowing frame is also connected with an air supply assembly. The air supply pump assembly is used to make the impact air holes blow out air flow, and the air flow blown out by the impact air holes blows towards the inner wall of the soaking reaction vessel and forms a reflected air flow on the inner wall of the soaking reaction vessel. Multiple groups of the blowing frames are uniformly arranged along the circumferential direction of the inner wall of the soaking reaction vessel.

[0010] In a preferred embodiment, a supply air rotating pipe is rotatably arranged inside the soaking reaction vessel. The blowing frame is connected with the supply air rotating pipe through a connecting frame. When the supply air rotating pipe rotates, it drives the blowing frame to move along the inner wall of the soaking reaction vessel.

[0011] In a preferred embodiment, the air supply assembly includes an air supply sleeve which is fixedly installed on the top of the soaking reaction vessel. The supply air rotating pipe is rotatably installed inside the air supply sleeve. A sealing structure is arranged between the supply air rotating pipe and the air supply sleeve. The air supply sleeve is connected with an air supply pump through a pipeline. The blowing frame is of a hollow structure. The impact air holes are communicated with the hollow structure of the blowing frame. A communicating air passage for communicating the inner cavity of the blowing frame and the inner cavity of the supply air rotating pipe is arranged in the connecting frame.

[0012] In a preferred embodiment, a downward extension pipe is fixedly installed inside the supply air rotating pipe. A gap is formed between the supply air rotating pipe and the downward extension pipe. The top end of the downward extension pipe is in rotational fit with the feed pipe and is provided with a sealing structure. The downward extension pipe is rotationally driven by a rotation driver.

[0013] In a preferred embodiment, the blowing frame is a fixed blowing plate which is fixedly installed on the connecting frame. The fixed blowing plate is of a triangular plate structure. The impact air holes are inclined air holes which are formed on the side surface of the fixed blowing plate. The inclined air holes are communicated with the inner cavity of the fixed blowing plate. The communicating air passage is also communicated with the inner cavity of the fixed blowing plate.

[0014] In a preferred embodiment, the blowing frame is a rotating blowing pipe which is rotatably installed on the connecting frame. A runner structure is fixedly connected to the rotating blowing pipe. The runner structure is in rolling fit with the inner wall of the soaking reaction vessel. The impact air holes are radial air holes which are holes distributed along the radial direction of the rotating blowing pipe. And multiple groups of the rotating blowing pipes are arranged along the circumferential direction of the rotating blowing pipe. An arc-shaped baffle is also fixedly connected to the communicating air passage. The arc-shaped baffle is located on the side of the rotating blowing pipe away from the inner wall of the soaking reaction vessel. When the radial air holes are butted with the communicating air passage, the communicating air passage is communicated with the inner cavity of the rotating blowing pipe.

[0015] In a preferred embodiment, an extension plate is fixedly connected to the bottom end of the downward extension pipe, a material leveling baffle is rotatably connected to the extension plate, and a weight structure is fixedly connected to the bottom end of the material leveling baffle.

[0016] In a preferred embodiment, an air equalizing hood is arranged at the bottom of the inner cavity of the soaking reaction vessel. The air equalizing hood is located above the air inlet, and a plurality of groups of air equalizing holes are uniformly arranged on the air equalizing hood.

[0017] In a preferred embodiment, the discharge port is arranged on one side of the bottom of the soaking reaction vessel, and the air equalizing hood is of a conical structure. The discharge port is located above the edge of the air equalizing hood. An activity plug is arranged at the position corresponding to the air equalizing hole on the air equalizing hood. The activity plug is in sliding fit with the air equalizing hole. The top and bottom of the activity plug are both of an arc structure, and an adaptation groove adapted to the bottom of the activity plug is arranged on the air equalizing hole.

[0018] The beneficial effects of the present invention are as follows: The present invention can form multiple groups of reflected airflows on the inner wall of the soaking reaction vessel, reducing the probability that the catalyst particles adhere to and attach to the inner wall of the soaking reaction vessel, thereby avoiding the influence of the catalyst particles adhering to the inner wall of the soaking reaction vessel for a long time on their contact with the carbon-containing gas and the reaction to generate carbon nanotubes, further improving the relative purity of the produced carbon nanotubes and the production efficiency. At the same time, when the reflected airflows are formed on the inner wall of the soaking reaction vessel, the airflows can directly exchange heat when contacting the inner wall of the soaking reaction vessel, and when generating a movement trend towards the center of the soaking reaction vessel subsequently, a heat compensation for the central area of the soaking reaction vessel is formed, so that the control of the reaction temperature in the soaking reaction vessel is more uniform and sufficient, thus further ensuring the product quality during the large-scale production of carbon nanotubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart of the production method of the present invention.

[0020] Figure 2 It is a diagram of the equipment for producing carbon nanotubes according to the present invention.

[0021] Figure 3 It is a schematic diagram of the internal structure of the soaking reaction vessel of the present invention.

[0022] Figure 4 It is a schematic diagram of the cooperation between the feeding pipe and the downward extension pipe of the present invention.

[0023] Figure 5 It is a schematic diagram of the cooperation between the air supply rotating pipe and the air supply sleeve of the present invention.

[0024] Figure 6 It is a connection diagram of the air supply rotating pipe and the fixed blowing plate of the present invention.

[0025] Figure 7Distribution state diagram of the fixed blowing plate of the present invention in the soaking reaction vessel.

[0026] Figure 8 State diagram of the fixed blowing plate of the present invention when blowing air.

[0027] Figure 9 Structural schematic diagram of the rotary blowing pipe of the present invention.

[0028] Figure 10 Cooperating state diagram between the runner structure on the rotary blowing pipe of the present invention and the inner wall of the soaking reaction vessel.

[0029] Figure 11 Structural schematic diagram of the present invention after adding a material leveling baffle at the bottom of the downcomer.

[0030] Figure 12 Structural schematic diagram of the gas equalizing hood of the present invention.

[0031] Figure 13 For the present invention Figure 12 Enlarged view of the structure of part A.

[0032] Figure 14 State diagram of the present invention when the movable plug automatically descends to block the air equalizing holes after the reaction ends.

[0033] Reference numerals are: 1, soaking reaction vessel; 11, air inlet; 12, exhaust port; 13, discharge port; 2, heating assembly; 3, feeding assembly; 31, feeding pipe; 32, downcomer; 33, material leveling baffle; 331, counterweight structure; 4, auxiliary blowing assembly; 41, blowing frame; 411, fixed blowing plate; 412, rotary blowing pipe; 413, runner structure; 42, impact air holes; 421, inclined air holes; 422, radial air holes; 43, air supply rotary pipe; 431, communicating air holes; 432, connecting frame; 433, communicating air channels; 434, arc-shaped baffle; 44, air supply sleeve; 5, rotary drive; 6, gas equalizing hood; 61, air equalizing holes; 62, movable plug; 63, matching groove. Detailed implementation manners

[0034] The following further describes the present application in detail with reference to the drawings. It is necessary to point out here that the following specific implementation manners are only used to further illustrate the present application and cannot be understood as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application according to the above application content.

[0035] Referring to the attached Figure 1 description, a method for producing carbon nanotubes with uniform temperature control includes the following steps: Step 1: Catalyst preparation. Select the corresponding catalyst material (common catalysts include transition metals such as iron, cobalt, nickel or their alloys), and prepare it into granular catalyst powder for later use; Step 2: Feeding the catalyst powder. Mix the catalyst powder into the carrier gas (usually an inert gas such as nitrogen or argon, and the role of the carrier gas is to maintain the reaction environment), and introduce the carrier gas from the feeding component 3 into the interior of the soaking reaction vessel 1, so as to evenly put the catalyst powder into the soaking reaction vessel 1; Step 3: Feeding the carbon-containing gas. Introduce the carbon-containing gas (such as methane, acetylene, etc.) into the soaking reaction vessel 1 through the air inlet 11, and form an impact air flow of the carbon-containing gas and the carrier gas containing the catalyst powder; Step 4: Reaction heating. Heat the internal space of the soaking reaction vessel 1 through the heating component 2 to the reaction required temperature. At this temperature, the carbon-containing gas undergoes a pyrolysis reaction on the surface of the catalyst, and the generated carbon atoms combine with the catalyst particles and precipitate to form carbon nanotubes; Step 5: Auxiliary blowing. Input gas into the blowing frame 41, and make the impact air holes 42 blow out air flow, and the air flow blown out by the impact air holes 42 blows towards the inner wall of the soaking reaction vessel 1, and a reflected air flow is formed on the inner wall of the soaking reaction vessel 1; Step 6: Growth of carbon nanotubes. Maintain the above conditions for a period of time to allow the carbon nanotubes to continue growing until the required amount is reached; Step 7: Cooling and collection. After the growth process is completed, turn off the heating component 2 and wait for the system to cool naturally. Then, open the closing structure of the discharge port 13, such as a valve or a door, etc., and take out the product containing carbon nanotubes through the discharge port 13; Step 8: Purification treatment. Purify the obtained carbon nanotubes to remove impurities such as residual catalyst particles and amorphous carbon, so as to improve their quality and application performance. Common purification methods include steps such as acid washing, filtration, and centrifugal separation.

[0036] Based on the above production method, the specific structure of the soaking reaction vessel 1 used is as follows: Refer to the attached drawing of the specification Figures 2 to 14, an air inlet 11 and a discharge port 13 are provided at the bottom of the soaking reaction vessel 1, and an exhaust port 12 and a feeding assembly 3 are provided at the top of the soaking reaction vessel 1. Among them, the discharge port 13 is used to discharge the excess gas in the soaking reaction vessel 1, and the air inlet 11 is used to introduce carbon-containing gas into the soaking reaction vessel 1. The discharge port 13 is used to take out the generated carbon nanotubes after the reaction. The above schemes for the selection of carbon-containing gas, the input of gas, and the discharge of excess gas are all conventional techniques and operations for producing carbon nanotubes by chemical vapor deposition. This embodiment will not be elaborated too much. It should be noted that the feeding assembly 3 is provided at the top of the soaking reaction vessel 1 provided in this embodiment (different from the single feeding structure in the traditional technology). The feeding assembly 3 includes a feeding pipe 31 and a downward extension pipe 32. The downward extension pipe 32 extends into the soaking reaction vessel 1, so that when the catalyst powder material is put in, it can contact the carbon-containing gas source more deeply and form a catalytic reaction.

[0037] Secondly, a plurality of independent heating control zones are arranged from bottom to top inside the heating assembly 2 adopted in this embodiment, and the heating temperature of each zone can be set independently. Therefore, during actual production, the reaction temperature can be controlled more evenly and effectively according to needs to improve the reaction effect.

[0038] At the same time, an auxiliary blowing assembly 4 is further arranged inside the soaking reaction vessel 1 provided in this embodiment. The auxiliary blowing assembly 4 includes a blowing frame 41. The blowing frame 41 is arranged inside the soaking reaction vessel 1 close to the inner wall of the soaking reaction vessel 1. Impact air holes 42 are arranged on the blowing frame 41. The blowing frame 41 is also connected with a gas supply assembly. The gas supply assembly includes at least one set of air supply pump structures. The air supply pump assembly is used to make the impact air holes 42 blow out airflows, and the airflows blown out by the impact air holes 42 blow towards the inner wall of the soaking reaction vessel 1 and form reflected airflows on the inner wall of the soaking reaction vessel 1. Among them, a plurality of groups of blowing frames 41 are evenly arranged along the circumferential direction of the inner wall of the soaking reaction vessel 1.

[0039] It should be noted that in order not to affect the reaction generation of carbon nanotubes, the gas input by the blowing frame 41 is the same as the carrier gas mentioned above, or other inert gases that do not affect the reaction can also be used to ensure the relative purity of the gas in the soaking reaction vessel 1 and not affect the progress of the carbon nanotube reaction generation.

[0040] By adopting the above solution, multiple groups of reflected airflows can be formed on the inner wall of the soaking reaction vessel 1. Then, when the catalyst powder particles are put into the soaking reaction vessel 1 and approach the inner wall of the soaking reaction vessel 1, they can be blown by the above-mentioned reflected airflows towards the inner center of the soaking reaction vessel 1 (although irregular airflows need to be formed inside the soaking reaction vessel 1 to enable the catalyst powder particles to be evenly distributed within the soaking reaction vessel 1, due to the existence of airflows on the inner wall of the soaking reaction vessel 1, the probability of the catalyst particles adhering to and attaching to the inner wall of the soaking reaction vessel 1 is reduced), thereby preventing the catalyst particles from adhering to the inner wall of the soaking reaction vessel 1 for a long time and affecting their contact with the carbon-containing gas and the reaction to generate carbon nanotubes, further improving the relative purity of the produced carbon nanotubes and increasing the production efficiency (since the cost and price of carbon nanotubes are relatively high, even a small increase in the above production efficiency can relatively reduce the production cost).

[0041] It should be noted that when a large amount of carbon nanotubes need to be produced, to improve the production efficiency, the reaction space of the soaking reaction vessel 1 needs to be increased, thereby increasing the distance from the outer wall of the soaking reaction vessel 1 to the center of the inner cavity. At the same time, during the reaction, a large number of reactant particles also fill the inside of the soaking reaction vessel 1, which will affect the conduction of heat from the external heating component 2 to the center of the soaking reaction vessel 1 during heating. By adopting the above technical solution, when the reflected airflow is formed on the inner wall of the soaking reaction vessel 1, when the airflow contacts the inner wall of the soaking reaction vessel 1, heat exchange can be directly carried out, and when a movement trend towards the center of the soaking reaction vessel 1 is generated subsequently, a heat compensation for the central area of the soaking reaction vessel 1 is formed, thereby making the control of the reaction temperature inside the soaking reaction vessel 1 more uniform and sufficient, and further ensuring the product quality during the large-scale production of carbon nanotubes.

[0042] Furthermore, in the above embodiment, referring to the attached drawings of the specification Figure 3 , a gas supply rotating pipe 43 is rotatably arranged inside the soaking reaction vessel 1. The blowing frame 41 is connected to the gas supply rotating pipe 43 through a connecting frame 432. When the gas supply rotating pipe 43 rotates, it drives the blowing frame 41 to move along the inner wall of the soaking reaction vessel 1, so that the position corresponding to the airflow blown out by the impact air holes 42 also continuously changes, thereby improving the blocking effect on the catalyst powder particles. At the same time, the position of the airflow blown out by the impact air holes 42 also continuously changes along the inner wall of the soaking reaction vessel 1, thereby forming a cleaning effect on the inner wall of the soaking reaction vessel 1. Without generating friction with the inner wall of the soaking reaction vessel 1, it can effectively prevent a large amount of catalyst powder particles and carbon nanotube materials from adhering to the inner wall of the soaking reaction vessel 1 and affecting subsequent production.

[0043] Referring to the attached drawings of the specification Figure 4 and Figure 5, the air supply assembly includes an air supply sleeve 44, the air supply sleeve 44 is fixedly installed at the top of the soaking reaction vessel 1, the air supply rotating pipe 43 is rotatably installed inside the air supply sleeve 44, a sealing structure is provided between the air supply rotating pipe 43 and the air supply sleeve 44, the air supply sleeve 44 is connected to an air supply pump through a pipeline, the blowing frame 41 is a hollow structure, the impact air holes 42 communicate with the hollow structure of the blowing frame 41, and a communication air passage 433 for communicating the inner cavity of the blowing frame 41 and the inner cavity of the air supply rotating pipe 43 is provided in the connecting frame 432.

[0044] Among them, the downward extension pipe 32 is fixedly installed inside the air supply rotating pipe 43, a gap is formed between the air supply rotating pipe 43 and the downward extension pipe 32, the top end of the downward extension pipe 32 is rotationally matched with the feed pipe 31 and is provided with a sealing structure, the downward extension pipe 32 is rotationally driven by a rotation driver 5, the soaking reaction vessel 1 and the rotation driver 5 are installed on the same frame, and the output shaft of the rotation driver 5 is in transmission cooperation with the downward extension pipe 32 through a belt assembly, so as to form a synchronous rotation drive for the downward extension pipe 32 and the air supply rotating pipe 43.

[0045] In the above embodiment, refer to the attached drawings of the specification Figures 6 to 8 , the blowing frame 41 is a fixed blowing plate 411, the fixed blowing plate 411 is fixedly installed on the connecting frame 432, the fixed blowing plate 411 is a triangular plate structure (that is, both sides of the fixed blowing plate 411 have symmetrical inclined surface structures), the impact air holes 42 are inclined air holes 421, the inclined air holes 421 are formed on the side surface of the fixed blowing plate 411, the inclined air holes 421 communicate with the inner cavity of the fixed blowing plate 411, and the communication air passage 433 also communicates with the inner cavity of the fixed blowing plate 411.

[0046] In addition, this embodiment also provides another blowing frame 41. Specifically, refer to the attached drawings of the specification Figure 9 and Figure 10, the air blowing frame 41 is a rotatable blowpipe 412. The rotatable blowpipe 412 is rotatably installed on the connecting frame 432. A runner structure 413 is fixedly connected to the rotatable blowpipe 412. The runner structure 413 is in rolling cooperation with the inner wall of the soaking reaction vessel 1 (the soaking reaction vessel 1 is a cylindrical structure). When the air supply rotating pipe 43 rotates, the runner structure 413 cooperates with the inner wall of the soaking reaction vessel 1 and drives the rotatable blowpipe 412 to rotate. The impact air holes 42 are radial air holes 422. The radial air holes 422 are holes distributed along the radial direction of the rotatable blowpipe 412. And the rotatable blowpipe 412 is provided in multiple groups. The multiple groups of rotatable blowpipes 412 are distributed along the circumferential direction of the rotatable blowpipe 412. An arc-shaped baffle 434 is also fixedly connected to the communicating air duct 433. The arc-shaped baffle 434 is located on the side of the rotatable blowpipe 412 away from the inner wall of the soaking reaction vessel 1. The arc-shaped baffle 434 is in sliding cooperation with the circumferential wall of the rotatable blowpipe 412. When the radial air holes 422 are docked with the communicating air duct 433, the communicating air duct 433 is communicated with the inner cavity of the rotatable blowpipe 412, and the other radial air holes 422 that are not blocked by the arc-shaped baffle 434 and are close to the inner wall of the soaking reaction vessel 1 are blown out. Thus, in actual use, as the air supply rotating pipe 43 continuously rotates, the position of the air flow blown out by the radial air holes 422 continuously changes. At the same time, due to the self-rotation of the rotatable blowpipe 412, the angle of the air flow blown out by the radial air holes 422 also continuously changes, thereby further improving the blowing effect on the catalyst particles attached to the surface of the soaking reaction vessel 1, making the movement of the powder material in the soaking reaction vessel 1 more chaotic and the distribution more sufficient.

[0047] Further, in the above embodiment, since the output port of the downward extension pipe 32 is relatively fixed, the output state of the input catalyst powder material is also relatively stable, which is not conducive to the sufficient distribution after entering the soaking reaction vessel 1. For this reason, referring to the attached Figure 11 , an extension plate is fixedly connected to the bottom end of the downward extension pipe 32. A material leveling baffle 33 is rotatably connected to the extension plate. A weight structure 331 is fixedly connected to the bottom end of the material leveling baffle 33. Thus, in actual use, by controlling the rotation of the downward extension pipe 32, under the action of centrifugal force, the material leveling baffle 33 can be driven to turn outwards. Furthermore, by controlling the rotation speed change of the downward extension pipe 32, the inclination angle of the material leveling baffle 33 can be adjusted, thereby changing the distribution state of the output catalyst powder and improving the uniformity of the catalyst powder distribution.

[0048] It should be noted that, to maintain the rotation stability of the downward extension pipe 32, the material leveling baffle 33 is preferably provided in two groups. The two groups of material leveling baffles 33 are symmetrically arranged to ensure stable rotation.

[0049] In the above embodiments, in order to maintain the most direct contact between the carbon-containing gas and the catalyst powder, the air inlet 11 and the downward extension pipe 32 are preferably coaxially and vertically arranged to ensure the most direct contact between the two gases. At the same time, in order to improve the uniformity of the gas introduced by the air inlet 11, referring to the attached drawings of the specification Figure 11 , a gas equalizing cover 6 is arranged at the bottom of the inner cavity of the soaking reaction vessel 1. The gas equalizing cover 6 is located above the air inlet 11. A plurality of groups of gas equalizing holes 61 are uniformly arranged on the gas equalizing cover 6, so as to make the distribution of the carbon-containing gas source output by the air inlet 11 more uniform.

[0050] Furthermore, since the air inlet 11 is vertically arranged, wherein, for the convenience of discharging materials, the discharge port 13 is arranged on one side of the bottom of the soaking reaction vessel 1, and the gas equalizing cover 6 is of a conical structure. The discharge port 13 is located above the edge of the gas equalizing cover 6. A movable plug 62 is arranged at the position corresponding to the gas equalizing hole 61 on the gas equalizing cover 6. The gas equalizing hole 61 is slidably matched with the gas equalizing hole 61. Specifically, a sliding rod is arranged on the movable plug 62, and a guiding frame is arranged in the gas equalizing hole 61. The above sliding rod is slidably installed in the guiding frame, and a corresponding limiting structure is arranged. The top and bottom of the movable plug 62 are both of an arc-shaped structure, and an adapting groove 63 adapted to the bottom of the movable plug 62 is arranged on the gas equalizing hole 61.

[0051] It should be noted that during the actual reaction stage, the air inlet 11 continuously outputs air flow. This air flow passes through the gas equalizing holes 61 and jacks up the movable plug 62 to make the gas equalizing holes 61 conduct, so as to ensure that the carbon-containing gas is output from the gas equalizing cover 6. At the same time, under the action of the arc-shaped surface at the bottom of the movable plug 62, the air flow blown out from the gas equalizing holes 61 is distributed in a horn shape, and thus is more sufficient and uniform. When the reaction ends and the air supply to the air inlet 11 is stopped, the movable plug 62 automatically falls under the action of its own weight and is clamped into the adapting groove 63 to block the gas equalizing holes 61. At this time, the gas equalizing cover 6 as a whole is in a conical guiding structure, so that the generated carbon nanotube material can be taken out more conveniently, improving the practicability of the equipment.

[0052] The above-described embodiments merely represent several embodiments of the present invention. Their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the patent of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A method for producing carbon nanotubes with uniform temperature control, characterized in that, It includes the following steps: Step 1, catalyst preparation: Select the corresponding catalyst material and prepare it into granular catalyst powder for use; Step 2, putting the catalyst powder: Mix the catalyst powder into the carrier gas and introduce the carrier gas from the feeding component (3) into the inside of the soaking reaction vessel (1); Step 3, putting the carbon-containing gas: Introduce the carbon-containing gas into the soaking reaction vessel (1) through the air inlet (11) and form an impact air flow of the carbon-containing gas and the carrier gas containing the catalyst powder; Step 4, reaction heating: Heat the internal space of the soaking reaction vessel (1) through the heating component (2) to the temperature required for the reaction; Step 5, auxiliary blowing: Input gas into the blowing frame (41) and make the impact air holes (42) blow out air flow, and the air flow blown out by the impact air holes (42) blows towards the inner wall of the soaking reaction vessel (1) and forms a reflected air flow on the inner wall of the soaking reaction vessel (1); Step 6, carbon nanotube growth: Keep the above conditions until the carbon nanotubes continue to grow until the required amount is reached; Step 7, cooling and collection: After the growth process is completed, turn off the heating component (2) and wait for the system to cool naturally. Then, open the closing structure of the discharge port (13) and take out the product containing carbon nanotubes.

2. A method for producing carbon nanotubes with uniform temperature control according to claim 1, characterized in that: At the bottom of the soaking reaction vessel (1) in Step 2, there are an air inlet (11) and a discharge port (13). At the top of the soaking reaction vessel (1), there are an exhaust port (12) and a feeding component (3). The feeding component (3) includes a feeding pipe (31) and a downward extension pipe (32), and the downward extension pipe (32) extends into the inside of the soaking reaction vessel (1); An auxiliary blowing component (4) is also arranged inside the soaking reaction vessel (1). The auxiliary blowing component (4) includes a blowing frame (41). The blowing frame (41) is arranged inside the soaking reaction vessel (1) close to the inner wall of the soaking reaction vessel (1). Impact air holes (42) are arranged on the blowing frame (41). The blowing frame (41) is also connected with a gas supply component. This gas supply pump component is used to make the impact air holes (42) blow out air flow, and the air flow blown out by the impact air holes (42) blows towards the inner wall of the soaking reaction vessel (1) and forms a reflected air flow on the inner wall of the soaking reaction vessel (1). Multiple groups of the blowing frames (41) are uniformly arranged along the circumferential direction of the inner wall of the soaking reaction vessel (1).

3. A method for producing carbon nanotubes with uniform temperature control according to claim 2, characterized in that: A gas supply rotating pipe (43) is rotatably arranged inside the soaking reaction vessel (1). The blowing frame (41) is connected with the gas supply rotating pipe (43) through a connecting frame (432). When the gas supply rotating pipe (43) rotates, it drives the blowing frame (41) to move along the inner wall of the soaking reaction vessel (1).

4. A method for producing carbon nanotubes with uniform temperature control according to claim 3, characterized in that: The air supply assembly includes an air supply sleeve (44) fixedly installed at the top of the soaking reaction vessel (1). An air supply rotating pipe (43) is rotatably installed inside the air supply sleeve (44). A sealing structure is provided between the air supply rotating pipe (43) and the air supply sleeve (44). The air supply sleeve (44) is connected to an air supply pump through a pipeline. The blowing frame (41) is of a hollow structure. The impact air holes (42) communicate with the hollow structure of the blowing frame (41). A communication air passage (433) for communicating the inner cavity of the blowing frame (41) and the inner cavity of the air supply rotating pipe (43) is provided in the connecting frame (432).

5. A method for producing carbon nanotubes with uniform temperature control according to claim 4, characterized in that: The downward extension pipe (32) is fixedly installed inside the air supply rotating pipe (43). A gap is formed between the air supply rotating pipe (43) and the downward extension pipe (32). The top end of the downward extension pipe (32) is rotatably matched with the feed pipe (31), and a sealing structure is provided. The downward extension pipe (32) is rotationally driven by a rotation drive (5).

6. A method for producing carbon nanotubes with uniform temperature control according to claim 5, characterized in that: The blowing frame (41) is a fixed blowing plate (411). The fixed blowing plate (411) is fixedly installed on the connecting frame (432). The fixed blowing plate (411) is of a triangular plate structure. The impact air holes (42) are inclined air holes (421). The inclined air holes (421) are formed on the side surface of the fixed blowing plate (411). The inclined air holes (421) communicate with the inner cavity of the fixed blowing plate (411). The communication air passage (433) also communicates with the inner cavity of the fixed blowing plate (411).

7. A method for producing carbon nanotubes with uniform temperature control according to claim 5, characterized in that: The blowing frame (41) is a rotating blowing pipe (412). The rotating blowing pipe (412) is rotatably installed on the connecting frame (432). A runner structure (413) is fixedly connected to the rotating blowing pipe (412). The runner structure (413) is in rolling fit with the inner wall of the soaking reaction vessel (1). The impact air holes (42) are radial air holes (422). The radial air holes (422) are holes distributed along the radial direction of the rotating blowing pipe (412). And the rotating blowing pipes (412) are arranged in multiple groups. The multiple groups of rotating blowing pipes (412) are distributed along the circumferential direction of the rotating blowing pipe (412). An arc-shaped baffle (434) is also fixedly connected to the communication air passage (433). The arc-shaped baffle (434) is located on the side of the rotating blowing pipe (412) away from the inner wall of the soaking reaction vessel (1). When the radial air holes (422) are butted with the communication air passage (433), the communication air passage (433) communicates with the inner cavity of the rotating blowing pipe (412).

8. A method for producing carbon nanotubes with uniform temperature control according to claim 6 or 7, characterized in that: The bottom end of the downward extension pipe (32) is fixedly connected with an extension plate. A material leveling baffle (33) is rotatably connected to the extension plate. A weight structure (331) is fixedly connected to the bottom end of the material leveling baffle (33).

9. A method for producing carbon nanotubes with uniform temperature control according to claim 8, characterized in that: An air equalizing hood (6) is provided at the bottom of the inner cavity of the soaking reaction vessel (1). The air equalizing hood (6) is located above the air inlet (11). Multiple groups of air equalizing holes (61) are evenly arranged on the air equalizing hood (6).

10. A method for producing carbon nanotubes with uniform temperature control according to claim 9, characterized in that: The discharge port (13) is arranged on one side of the bottom of the soaking reaction vessel (1), and the gas equalizing hood (6) is of a conical structure. The discharge port (13) is located above the edge of the gas equalizing hood (6). An activity plug (62) is arranged at the position corresponding to the gas equalizing holes (61) on the gas equalizing hood (6). The activity plug (62) is in sliding fit with the gas equalizing holes (61). The top and bottom of the activity plug (62) are both arranged in an arc structure. An adaptation groove (63) adapted to the bottom of the activity plug (62) is arranged on the gas equalizing holes (61).

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