A method for producing carbon nanotubes with uniform temperature control

Abstract

The application discloses a carbon nanotube production method with uniform temperature control, and particularly relates to the technical field of carbon nanotube production, which comprises catalyst preparation, catalyst powder feeding, carbon-containing gas feeding, reaction heating, auxiliary gas blowing, gas input into a gas blowing frame, and gas flow blown out of the impact gas hole, wherein the gas flow blown out of the impact gas hole blows towards the inner wall of the uniform heating reaction container, and forms a reflected gas flow on the inner wall of the uniform heating reaction container, carbon nanotube growth, and cooling and collection. The application can form multiple groups of reflected gas flows on the inner wall of the uniform heating reaction container, so that the probability of catalyst particles adhering to and attaching to the inner wall of the uniform heating reaction container is reduced, thereby avoiding the catalyst particles from adhering to the inner wall of the uniform heating reaction container for a long time, and affecting the contact of the catalyst particles with the carbon-containing gas and the reaction generation of the carbon nanotubes, and further improving the relative purity of the produced carbon nanotubes and the production efficiency.

Description

Technical Field

[0001] This invention relates to the field of carbon nanotube production technology, and more specifically, to a method for producing carbon nanotubes with uniform temperature control. Background Technology

[0002] Carbon nanotubes, as one-dimensional nanomaterials, are lightweight, have a perfectly connected hexagonal structure, and possess many exceptional mechanical, electrical, and chemical properties. In recent years, with the deepening research into carbon nanotubes and nanomaterials, their broad application prospects have become increasingly apparent.

[0003] The main methods for preparing carbon nanotubes include arc discharge, laser ablation, and chemical vapor deposition (CVD). Among these, CVD is the preferred method for growing carbon nanotube arrays due to its good stability and low cost. Its basic principle involves using catalyst particles (such as metals like iron, cobalt, and nickel) as a substrate and introducing a carbon source gas (such as hydrocarbons like methane and acetylene) and a carrier gas (such as hydrogen or an inert gas) into the reaction chamber. These gases decompose under heating conditions, releasing active carbon atoms. The catalyst particles act as nucleation sites, and under high temperatures (typically between 600°C and 900°C), carbon-containing gas molecules are adsorbed and activated on the catalyst surface, causing them to undergo a cracking reaction to generate carbon atoms. During this process, hydrogen acts as a reducing agent to help remove oxides from the catalyst surface, improving 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 preparation of carbon nanotubes by chemical vapor deposition (CVD) mainly requires a reaction vessel, a heating system, and a gas delivery system. The reaction vessel, typically a sealed cavity, is the site of the chemical reaction and can withstand certain temperatures and pressures. During CVD, the reaction chamber needs to provide a controlled environment to promote the decomposition of the precursor gas and the growth of carbon nanotubes. The heating system is used to bring the reaction vessel to the required reaction temperature, and can use different methods such as resistance heating, induction heating, or infrared heating. The heating system ensures that the substrate surface reaches a sufficient temperature to activate surface atoms and promote the chemical reaction. The gas delivery system is responsible for precisely delivering various gases (such as carrier gas, carbon source gas, and reducing gas) into the reaction chamber and maintaining an appropriate flow rate ratio.

[0005] In the industrial production process of carbon nanotubes, particulate catalysts are required. This involves adding a corresponding amount of catalyst powder to a reaction vessel and reacting it with a carbon-source-containing gas in the vessel. Simultaneously, airflow is used to ensure that the catalyst powder is fully distributed in the reaction vessel and undergoes a complete reaction to obtain a relatively large amount of carbon nanotube material.

[0006] However, for production processes with high production volume requirements, the amount of catalyst powder input is also relatively larger. During input, under the action of airflow in the reaction vessel, some catalyst particles will move to the inner wall of the vessel and form adhesion. The exposed surface area of ​​these catalyst particles is reduced due to the shielding effect of the inner wall of the reaction vessel, which in turn reduces their contact rate with the carbon-containing gas source. Consequently, the reaction between these catalyst particles and carbon atoms is not sufficient, affecting the actual purity of the produced carbon nanotubes, increasing the workload of the purification process, and raising production costs. Summary of the Invention

[0007] The present invention provides a method for producing carbon nanotubes with uniform temperature control. The problem to be solved is that in existing production processes with large production volume requirements, the catalyst powder particles will move to the inner wall of the container, which reduces the contact rate between the catalyst particles and the carbon-containing gas source. As a result, the reaction between the catalyst particles and carbon atoms is not sufficient, affecting the actual purity of the produced carbon nanotubes.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method for producing carbon nanotubes with uniform temperature control, comprising the following steps:

[0009] Step 1: Catalyst preparation. Select appropriate catalyst materials and prepare them into granular catalyst powders for later use.

[0010] Step 2: Add catalyst powder, mix the catalyst powder into the carrier gas, and introduce the carrier gas from the feed assembly into the interior of the homogenizing reaction vessel;

[0011] Step 3: Introduce carbon-containing gas into the homogenizing reaction vessel through the gas inlet, forming an impact gas flow between the carbon-containing gas and the carrier gas containing catalyst powder.

[0012] Step 4: Heating the reaction. The internal space of the homogenizing reaction vessel is heated to the required reaction temperature using the heating components.

[0013] Step 5: Assisted blowing. Gas is introduced into the blowing frame, and the airflow is blown out through the impact air hole. The airflow blown out through the impact air hole blows towards the inner wall of the homogenizing reaction vessel, and a reflected airflow is formed on the inner wall of the homogenizing reaction vessel.

[0014] Step 6: Carbon nanotube growth. Maintain the above conditions until the carbon nanotubes continue to grow to the required amount.

[0015] Step 7: Cooling and Collection. After the growth process is complete, turn off the heating components and wait for the system to cool down naturally. Then, open the closed structure of the discharge port and take out the product containing carbon nanotubes.

[0016] In a preferred embodiment, in step two, the bottom of the homogenizing reaction vessel is provided with an air inlet and a discharge outlet, and the top of the homogenizing reaction vessel is provided with an exhaust outlet and a feeding assembly. The feeding assembly includes a feeding pipe and a lower extension pipe, with the lower extension pipe extending into the interior of the homogenizing reaction vessel.

[0017] An auxiliary air blowing assembly is also provided inside the homogenizing reaction vessel. The auxiliary air blowing assembly includes an air blowing frame, which is located inside the homogenizing reaction vessel near the inner wall of the homogenizing reaction vessel. The air blowing frame is provided with impact air holes. The air blowing frame is also connected to an air supply assembly. The air supply pump assembly is used to blow air out of the impact air holes. The air blown out of the impact air holes blows towards the inner wall of the homogenizing reaction vessel and forms a reflected airflow on the inner wall of the homogenizing reaction vessel. Multiple sets of air blowing frames are evenly arranged along the circumference of the inner wall of the homogenizing reaction vessel.

[0018] In a preferred embodiment, a gas supply pipe is rotatably installed inside the homogenizing reaction vessel, and an air blowing frame is connected to the gas supply pipe via a connecting frame. When the gas supply pipe rotates, it drives the air blowing frame to move along the inner wall of the homogenizing reaction vessel.

[0019] In a preferred embodiment, the gas supply assembly includes a gas supply sleeve, which is fixedly installed on the top of the homogenizing reaction vessel. A gas supply transfer pipe is rotatably installed inside the gas supply sleeve. A sealing structure is provided between the gas supply transfer pipe and the gas supply sleeve. The gas supply sleeve is connected to a gas supply pump through a pipe. The gas blowing frame has a hollow structure. The impact air hole is connected to the hollow structure of the gas blowing frame. A connecting frame is provided with a connecting air passage for connecting the inner cavity of the gas blowing frame and the inner cavity of the gas supply transfer pipe.

[0020] In a preferred embodiment, the lower extension tube is fixedly installed inside the air supply tube, a gap is formed between the air supply tube and the lower extension tube, the top end of the lower extension tube is rotatably engaged with the feed tube and is provided with a sealing structure, and the lower extension tube is driven to rotate by a rotary driver.

[0021] In a preferred embodiment, the air blowing frame is a fixed air blowing plate, which is fixedly installed on the connecting frame. The fixed air blowing plate has a triangular plate structure, and the impact air holes are oblique air holes formed on the side of the fixed air blowing plate. The oblique air holes are connected to the inner cavity of the fixed air blowing plate, and the connecting air passage is also connected to the inner cavity of the fixed air blowing plate.

[0022] In a preferred embodiment, the blowing frame is a rotating blowing pipe, which is rotatably mounted on the connecting frame. A rotating wheel structure is fixedly connected to the rotating blowing pipe, and the rotating wheel structure rolls in cooperation with the inner wall of the homogenizing reaction vessel. The impact air holes are radial air holes, which are holes distributed radially along the rotating blowing pipe. Multiple sets of rotating blowing pipes are set, and the multiple sets of rotating blowing pipes are distributed along the circumference of the rotating blowing pipe. An arc-shaped baffle is also fixedly connected to the connecting air channel. The arc-shaped baffle is located on the side of the rotating blowing pipe away from the inner wall of the homogenizing reaction vessel. When the radial air holes are connected to the connecting air channel, the connecting air channel is connected to the inner cavity of the rotating blowing pipe.

[0023] In a preferred embodiment, an extension plate is fixedly connected to the bottom end of the lower extension tube, a material distribution baffle is rotatably connected to the extension plate, and a counterweight structure is fixedly connected to the bottom end of the material distribution baffle.

[0024] In a preferred embodiment, a gas equalization hood is provided at the bottom of the inner cavity of the homogenizing reaction vessel. The gas equalization hood is located above the air inlet, and multiple sets of gas equalization holes are evenly arranged on the gas equalization hood.

[0025] In a preferred embodiment, the discharge port is located on one side of the bottom of the homogenizing reaction vessel, and the gas equalization hood is a conical structure. The discharge port is located above the edge of the gas equalization hood. A movable plug is provided on the gas equalization hood at the position corresponding to the gas equalization hole. The gas equalization hole slides with the gas equalization hole. The top and bottom of the movable plug are both set as arc-shaped structures. The gas equalization hole is provided with an adaptation groove that matches the bottom of the movable plug.

[0026] The beneficial effects of this invention are as follows: This invention can form multiple sets of reflective airflows on the inner wall of the homogenizing reaction vessel, thereby reducing the probability of catalyst particles adhering to and attaching to the inner wall of the homogenizing reaction vessel. This avoids the catalyst particles adhering to the inner wall of the homogenizing reaction vessel for a long time, which would affect their contact with carbon-containing gas and the reaction formation of carbon nanotubes. This further improves the relative purity of the produced carbon nanotubes and increases production efficiency. At the same time, when the reflective airflow is formed on the inner wall of the homogenizing reaction vessel, the airflow can directly exchange heat when it comes into contact with the inner wall of the homogenizing reaction vessel. When it subsequently tends to move towards the center of the homogenizing reaction vessel, it forms heat compensation for the central region of the homogenizing reaction vessel, thereby making the control of the reaction temperature in the homogenizing reaction vessel more uniform and sufficient, thus further ensuring the product quality when producing carbon nanotubes in large quantities. Attached Figure Description

[0027] Figure 1 This is a flowchart of the production method of the present invention.

[0028] Figure 2 This is a diagram of the equipment used to produce carbon nanotubes according to the present invention.

[0029] Figure 3This is a schematic diagram of the internal structure of the homogenizing reaction vessel of the present invention.

[0030] Figure 4 This is a schematic diagram showing the fit between the feeding tube and the lower extension tube of the present invention.

[0031] Figure 5 This is a schematic diagram showing the fit between the gas supply pipe and the gas supply sleeve of the present invention.

[0032] Figure 6 This is a schematic diagram showing the connection between the air supply pipe and the fixed air blowing plate of the present invention.

[0033] Figure 7 This is a diagram showing the distribution of the fixed air blowing plate of the present invention within the homogenizing reaction vessel.

[0034] Figure 8 This is a diagram showing the state of the fixed air blowing plate of the present invention during air blowing.

[0035] Figure 9 This is a schematic diagram of the rotating air blowing tube of the present invention.

[0036] Figure 10 This diagram shows the fit between the rotating wheel structure on the rotating air blowing pipe of the present invention and the inner wall of the homogenizing reaction vessel.

[0037] Figure 11 This is a schematic diagram of the structure of the present invention after adding a material equalization baffle at the bottom of the lower extension tube.

[0038] Figure 12 This is a schematic diagram of the structure of the gas equalization hood of the present invention.

[0039] Figure 13 For the present invention Figure 12 Enlarged view of the structure of part A.

[0040] Figure 14 This is a diagram showing the state of the movable plug automatically descending to seal the gas equalization hole after the reaction of the present invention.

[0041] The attached figures are labeled as follows: 1. Homogenizing reaction vessel; 11. Air inlet; 12. Exhaust outlet; 13. Discharge outlet; 2. Heating assembly; 3. Feeding assembly; 31. Feed pipe; 32. Lower extension pipe; 33. Homogenizing baffle; 331. Counterweight structure; 4. Auxiliary air blowing assembly; 41. Air blowing frame; 411. Fixed air blowing plate; 412. Rotary air blowing pipe; 413. Rotary wheel structure; 42. Impact air hole; 421. Angled air hole; 422. Radial air hole; 43. Air supply pipe; 431. Connecting air hole; 432. Connecting frame; 433. Connecting air passage; 434. Arc-shaped baffle; 44. Air supply sleeve; 5. Rotary actuator; 6. Gas equalization hood; 61. Gas equalization hole; 62. Movable plug; 63. Adaptive groove. Detailed Implementation

[0042] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0043] Refer to the instruction manual appendix Figure 1 A method for producing carbon nanotubes with uniform temperature control includes the following steps:

[0044] Step 1: Catalyst preparation. Select appropriate catalyst materials (common catalysts include transition metals such as iron, cobalt, and nickel, or their alloys), and prepare them into granular catalyst powders for later use.

[0045] Step 2: Add catalyst powder. Mix the catalyst powder into the carrier gas (usually an inert gas such as nitrogen or argon, the role of the carrier gas is to maintain the reaction environment), and introduce the carrier gas from the feed assembly 3 into the interior of the homogenizing reaction vessel 1 so as to uniformly add the catalyst powder into the homogenizing reaction vessel 1.

[0046] Step 3: Introduce carbon-containing gas (such as methane, acetylene, etc.) into the homogenizing reaction vessel 1 through the gas inlet 11, and form an impact gas flow between the carbon-containing gas and the carrier gas containing catalyst powder.

[0047] Step 4: Reaction heating. The internal space of the homogenizing reaction vessel 1 is heated by the heating component 2 to the temperature required for the reaction. 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.

[0048] Step 5: Assisted blowing. Gas is input into the blowing frame 41 and the airflow is blown out by the impact air hole 42. The airflow blown out by the impact air hole 42 blows towards the inner wall of the homogenized reaction vessel 1 and forms a reflected airflow on the inner wall of the homogenized reaction vessel 1.

[0049] Step 6: Carbon nanotube growth. Maintain the above conditions for a period of time to allow the carbon nanotubes to continue growing until the required amount is reached.

[0050] Step 7: Cooling and Collection. After the growth process is completed, turn off the heating component 2 and wait for the system to cool down naturally. Then, open the closed structure of the discharge port 13, such as a valve or door, and take out the product containing carbon nanotubes through the discharge port 13.

[0051] Step 8: Purification treatment. The obtained carbon nanotubes are purified to remove residual catalyst particles and amorphous carbon and other impurities to improve their quality and application performance. Common purification methods include acid washing, filtration, centrifugation and other steps.

[0052] Based on the above production method, the specific structure of the homogenizing reaction vessel 1 used is as follows: (Refer to the appendix of the instruction manual) Figures 2 to 14 The homogenizing reaction vessel 1 is provided with an air inlet 11 and a discharge port 13 at the bottom, and an exhaust port 12 and a feeding assembly 3 at the top. The discharge port 13 is used to discharge excess gas in the homogenizing reaction vessel 1, while the air inlet 11 is used to introduce carbon-containing gas into the homogenizing reaction vessel 1. The discharge port 13 is used to remove the generated carbon nanotubes after the reaction is completed. The above-mentioned methods for selecting carbon-containing gas, inputting gas, and discharging excess gas are all conventional techniques and operations for producing carbon nanotubes by chemical vapor deposition. This embodiment will not explain them in detail. It should be noted that the top of the homogenizing reaction vessel 1 provided in this embodiment is provided with a feeding assembly 3 (different from the single feeding structure in the traditional technology). The feeding assembly 3 includes a feeding pipe 31 and a lower extension pipe 32. The lower extension pipe 32 extends into the interior of the homogenizing reaction vessel 1, so that the catalyst powder material can come into deeper contact with the carbon-containing gas source and form a catalytic reaction when it is added.

[0053] Secondly, the heating component 2 used in this embodiment has multiple independent heating control zones arranged from bottom to top inside, and the heating temperature of each zone can be set independently. Therefore, in actual production, the reaction temperature can be controlled more evenly and effectively as needed to improve the reaction effect.

[0054] Meanwhile, the interior of the homogenizing reaction vessel 1 provided in this embodiment is also provided with an auxiliary air blowing assembly 4. The auxiliary air blowing assembly 4 includes an air blowing frame 41, which is disposed inside the homogenizing reaction vessel 1 near the inner wall of the homogenizing reaction vessel 1. The air blowing frame 41 is provided with an impact air hole 42. The air blowing frame 41 is also connected to an air supply assembly. The air supply assembly includes at least one set of air supply pump structure. The air supply pump assembly is used to blow air out of the impact air hole 42, and the air out of the impact air hole 42 blows toward the inner wall of the homogenizing reaction vessel 1, and forms a reflected airflow on the inner wall of the homogenizing reaction vessel 1. There are multiple sets of air blowing frames 41 evenly arranged along the circumferential direction of the inner wall of the homogenizing reaction vessel 1.

[0055] It should be noted that, in order not to affect the reaction and generation of carbon nanotubes, the gas input into the gas blowing frame 41 is the same as the carrier gas mentioned above. Alternatively, other inert gases that do not affect the reaction can be used to ensure the relative purity of the gas in the homogenizing reaction vessel 1 and not affect the reaction and generation of carbon nanotubes.

[0056] By adopting the above scheme, multiple sets of reflective airflows can be formed on the inner wall of the homogenizing reaction vessel 1. When catalyst powder particles are added to the homogenizing reaction vessel 1 and approach the inner wall of the homogenizing reaction vessel 1, they can be blown towards the center of the homogenizing reaction vessel 1 by the above-mentioned reflective airflows. (Although irregular airflows need to be formed inside the homogenizing reaction vessel 1 to ensure that the catalyst powder particles can be evenly distributed inside the homogenizing reaction vessel 1, the probability of catalyst particles adhering to and attaching to the inner wall of the homogenizing reaction vessel 1 is reduced due to the presence of airflows on the inner wall of the homogenizing reaction vessel 1.) This avoids catalyst particles adhering to the inner wall of the homogenizing reaction vessel 1 for a long time, which would affect their contact with carbon-containing gas and the reaction generation of carbon nanotubes. This further improves the relative purity of the produced carbon nanotubes and increases production efficiency. (Since the cost and price of carbon nanotubes are relatively high, even a small increase in production efficiency can relatively reduce production costs.)

[0057] It should be noted that when mass production of carbon nanotubes is required, the reaction space of the homogenizing reaction vessel 1 needs to be increased to improve production efficiency. This increases the distance from the outer wall of the homogenizing reaction vessel 1 to the center of the inner cavity. At the same time, during the reaction, the inside of the homogenizing reaction vessel 1 is also filled with a large number of reactant particles, which will affect the heat conduction from the external heating component 2 to the center of the homogenizing reaction vessel 1. By adopting the above technical solution, when a reflective airflow is formed on the inner wall of the homogenizing reaction vessel 1, the airflow can directly exchange heat when it comes into contact with the inner wall of the homogenizing reaction vessel 1. When the airflow subsequently tends to move towards the center of the homogenizing reaction vessel 1, it forms heat compensation for the central region of the homogenizing reaction vessel 1. This makes the control of the reaction temperature inside the homogenizing reaction vessel 1 more uniform and sufficient, thereby further ensuring the product quality when mass-producing carbon nanotubes.

[0058] Furthermore, in the above embodiments, refer to the appendix to the specification. Figure 3 The homogenizing reaction vessel 1 is equipped with a rotating gas supply pipe 43. The gas blowing frame 41 is connected to the gas supply pipe 43 via a connecting frame 432. When the gas supply pipe 43 rotates, it drives the gas blowing frame 41 to move along the inner wall of the homogenizing reaction vessel 1, thereby constantly changing the position of the airflow blown out by the impact air hole 42. This improves the blocking effect on catalyst powder particles. At the same time, the position of the airflow blown out by the impact air hole 42 also changes continuously along the inner wall of the homogenizing reaction vessel 1, thus forming a cleaning effect on the inner wall of the homogenizing reaction vessel 1. Without generating friction with the inner wall of the homogenizing reaction vessel 1, it can effectively prevent a large number of catalyst powder particles and carbon nanotube materials from adhering to the inner wall of the homogenizing reaction vessel 1 and affecting subsequent production.

[0059] Refer to the instruction manual appendix Figure 4 and Figure 5The gas supply assembly includes a gas supply sleeve 44, which is fixedly installed on the top of the homogenizing reaction vessel 1. A gas supply transfer pipe 43 is rotatably installed inside the gas supply sleeve 44. A sealing structure is provided between the gas supply transfer pipe 43 and the gas supply sleeve 44. The gas supply sleeve 44 is connected to the gas supply pump through a pipe. The air blowing frame 41 has a hollow structure. The impact air hole 42 is connected to the hollow structure of the air blowing frame 41. A connecting frame 432 is provided with a connecting air passage 433 for connecting the inner cavity of the air blowing frame 41 and the inner cavity of the gas supply transfer pipe 43.

[0060] The lower extension tube 32 is fixedly installed inside the gas supply tube 43, and a gap is formed between the gas supply tube 43 and the lower extension tube 32. The top end of the lower extension tube 32 is rotatably engaged with the feed tube 31 and is provided with a sealing structure. The lower extension tube 32 is driven by the rotary driver 5. The homogenizing reaction vessel 1 and the rotary driver 5 are mounted on the same frame, and the output shaft of the rotary driver 5 is driven by the lower extension tube 32 through a belt assembly, thereby forming a synchronous rotation drive for the lower extension tube 32 and the gas supply tube 43.

[0061] In the above embodiments, please refer to the appendix to the specification. Figures 6 to 8 The air blowing frame 41 is a fixed air blowing plate 411, which is fixedly installed on the connecting frame 432. The fixed air blowing plate 411 has a triangular plate structure (that is, the two sides of the fixed air blowing plate 411 have symmetrical inclined structures). The impact air hole 42 is an oblique air hole 421, which is formed on the side of the fixed air blowing plate 411. The oblique air hole 421 is connected to the inner cavity of the fixed air blowing plate 411, and the connecting air passage 433 is also connected to the inner cavity of the fixed air blowing plate 411.

[0062] In addition, this embodiment also provides another type of air blower 41, for details please refer to the appendix of the instruction manual. Figure 9 and Figure 10The air blowing frame 41 is a rotating air blowing pipe 412, which is rotatably mounted on the connecting frame 432. A rotating wheel structure 413 is fixedly connected to the rotating air blowing pipe 412. The rotating wheel structure 413 rolls with the inner wall of the homogenizing reaction vessel 1 (the homogenizing reaction vessel 1 is a cylindrical structure). When the air blowing pipe 43 rotates, the rotating wheel structure 413 engages with the inner wall of the homogenizing reaction vessel 1 and drives the rotating air blowing pipe 412 to rotate. The impact air hole 42 is a radial air hole 422, which is a hole distributed radially along the rotating air blowing pipe 412. The rotating air blowing pipe 412 is configured in multiple sets, which are distributed along the circumference of the rotating air blowing pipe 412. An arc-shaped baffle 434 is also fixedly connected to the connecting air passage 433. The arc-shaped baffle 434 is located on the rotating air blowing pipe. On the side away from the inner wall of the homogenizing reaction vessel 1, the arc-shaped baffle 434 slides in cooperation with the circumferential wall of the rotating air blowing pipe 412. When the radial air hole 422 is connected to the connecting air channel 433, the connecting air channel 433 is connected to the inner cavity of the rotating air blowing pipe 412, and other radial air holes 422 that are not blocked by the arc-shaped baffle 434 and are close to the inner wall of the homogenizing reaction vessel 1 are blown out. In actual use, as the air supply pipe 43 rotates continuously, the position of the airflow blown out by the radial air hole 422 changes continuously. At the same time, due to the rotation of the rotating air blowing pipe 412, the angle of the airflow blown out by the radial air hole 422 also changes continuously, thereby further improving the blowing effect on the catalyst particles attached to the surface of the homogenizing reaction vessel 1, making the movement of powder materials in the homogenizing reaction vessel 1 more chaotic and the distribution more complete.

[0063] Furthermore, in the above embodiment, since the output port of the lower extension tube 32 is relatively fixed, the output state of the input catalyst powder material is also relatively stable, which is not conducive to its full distribution after entering the homogenizing reaction vessel 1. Therefore, please refer to the appendix of the specification. Figure 11 An extension plate is fixedly connected to the bottom end of the lower extension tube 32, and a uniform material baffle 33 is rotatably connected to the extension plate. A counterweight structure 331 is fixedly connected to the bottom end of the uniform material baffle 33. In actual use, by controlling the rotation of the lower extension tube 32, the uniform material baffle 33 can be driven to flip outward under the action of centrifugal force. By controlling the change of the rotation speed of the lower extension tube 32, the tilt angle of the uniform material baffle 33 can be adjusted, thereby changing the distribution state of the output catalyst powder and improving the uniformity of the catalyst powder distribution.

[0064] It should be noted that, in order to maintain the rotational stability of the lower extension tube 32, two sets of material distribution baffles 33 are preferably provided, and the two sets of material distribution baffles 33 are symmetrically arranged to ensure smooth rotation.

[0065] In the above embodiments, to maintain the most direct contact between the carbon-containing gas and the catalyst powder, the inlet 11 and the lower extension pipe 32 are preferably arranged coaxially and vertically to ensure the most direct contact between the two gases. Meanwhile, to improve the uniformity of the gas introduced through the inlet 11, please refer to the appendix to the instruction manual. Figure 11 A gas equalization hood 6 is provided at the bottom of the inner cavity of the homogenizing reaction vessel 1. The gas equalization hood 6 is located above the gas inlet 11. Multiple sets of gas equalization holes 61 are evenly arranged on the gas equalization hood 6, so that the carbon-containing gas source output from the gas inlet 11 is more evenly distributed.

[0066] Furthermore, since the air inlet 11 is vertically arranged, the discharge port 13 is located on one side of the bottom of the homogenizing reaction vessel 1 for easy unloading. The gas equalization hood 6 has a conical structure, and the discharge port 13 is located above the edge of the gas equalization hood 6. A movable plug 62 is provided on the gas equalization hood 6 at the position corresponding to the gas equalization hole 61. The gas equalization hole 61 is slidably engaged with the gas equalization hole 61. Specifically, a sliding rod is provided on the movable plug 62, and a guide frame is provided in the gas equalization hole 61. The sliding rod is slidably installed in the guide frame and is provided with a corresponding limiting structure. The top and bottom of the movable plug 62 are both set as arc-shaped structures, and the gas equalization hole 61 is provided with an adaptation groove 63 that is compatible with the bottom of the movable plug 62.

[0067] It should be noted that during the actual reaction stage, the air inlet 11 continuously outputs airflow, which passes through the equalization hole 61 and pushes the movable plug 62 upward, thus opening the equalization hole 61 and ensuring that the carbon-containing gas is output from the equalization hood 6. At the same time, under the action of the arc-shaped surface at the bottom of the movable plug 62, the airflow blown out of the equalization hole 61 is distributed in a trumpet shape, which makes it more thorough and uniform. When the reaction is over and the air supply to the air inlet 11 is stopped, the movable plug 62 automatically falls under the action of its weight and gets stuck in the matching groove 63, sealing the equalization hole 61. At this time, the equalization hood 6 has a cone-shaped guiding structure, which makes it easier to remove the generated carbon nanotube material and improves the practicality of the equipment.

[0068] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for producing carbon nanotubes with uniform temperature control, characterized in that, Includes the following steps: Step 1: Catalyst preparation. Select appropriate catalyst materials and prepare them into granular catalyst powders for later use. Step 2: Add catalyst powder, mix the catalyst powder into the carrier gas, and introduce the carrier gas from the feed assembly (3) into the interior of the homogenizing reaction vessel (1); Step 3: Introduce carbon-containing gas into the homogenizing reaction vessel (1) through the inlet (11) to form an impact flow of carbon-containing gas and carrier gas containing catalyst powder. Step 4: Heating the reaction. The internal space of the homogenizing reaction vessel (1) is heated by the heating component (2) to the required reaction temperature. Step 5: Assisted blowing, gas is input into the blowing frame (41), and airflow is blown out through the impact air hole (42), and the airflow blown out by the impact air hole (42) blows towards the inner wall of the homogenized reaction vessel (1), and a reflected airflow is formed on the inner wall of the homogenized reaction vessel (1); Step 6: Carbon nanotube growth. Maintain the above conditions until the carbon nanotubes continue to grow to the required amount. Step 7, Cooling and Collection: After the growth process is completed, turn off the heating component (2) and wait for the system to cool down naturally. Then, open the closed structure of the discharge port (13) and take out the product containing carbon nanotubes. In step two, the bottom of the homogenizing reaction vessel (1) is provided with an air inlet (11) and a discharge port (13), the top of the homogenizing reaction vessel (1) is provided with an exhaust port (12) and a feeding assembly (3), the top of the homogenizing reaction vessel (1) is provided with a feeding assembly (3), the feeding assembly (3) includes a feeding pipe (31) and a lower extension pipe (32), the lower extension pipe (32) extends into the interior of the homogenizing reaction vessel (1); An auxiliary air blowing assembly (4) is also provided inside the homogenizing reaction vessel (1). The auxiliary air blowing assembly (4) includes an air blowing frame (41). The air blowing frame (41) is located inside the homogenizing reaction vessel (1) near the inner wall of the homogenizing reaction vessel (1). The air blowing frame (41) is provided with an impact air hole (42). The air blowing frame (41) is also connected to an air supply assembly. The air supply assembly is used to blow air out of the impact air hole (42). The air out of the impact air hole (42) blows towards the inner wall of the homogenizing reaction vessel (1) and forms a reflected airflow on the inner wall of the homogenizing reaction vessel (1). Multiple sets of air blowing frames (41) are evenly arranged along the circumferential direction of the inner wall of the homogenizing reaction vessel (1). The homogenizing reaction vessel (1) is equipped with a rotating gas supply pipe (43). The gas blowing frame (41) is connected to the gas supply pipe (43) via a connecting frame (432). When the gas supply pipe (43) rotates, it drives the gas blowing frame (41) to move along the inner wall of the homogenizing reaction vessel (1).

2. The method for producing carbon nanotubes with uniform temperature control according to claim 1, characterized in that: The gas supply assembly includes a gas supply sleeve (44), which is fixedly installed on the top of the homogenizing reaction vessel (1). The gas supply transfer pipe (43) is rotatably installed inside the gas supply sleeve (44). A sealing structure is provided between the gas supply transfer pipe (43) and the gas supply sleeve (44). The gas supply sleeve (44) is connected to the gas supply pump through a pipe. The air blowing frame (41) has a hollow structure. The impact air hole (42) is connected to the hollow structure of the air blowing frame (41). The connecting frame (432) is provided with a connecting air passage (433) for connecting the inner cavity of the air blowing frame (41) and the inner cavity of the gas supply transfer pipe (43).

3. The method for producing carbon nanotubes with uniform temperature control according to claim 2, characterized in that: The lower extension tube (32) is fixedly installed inside the air supply tube (43). A gap is formed between the air supply tube (43) and the lower extension tube (32). The top end of the lower extension tube (32) is rotatably engaged with the feed tube (31) and is provided with a sealing structure. The lower extension tube (32) is driven to rotate by the rotation driver (5).

4. The method for producing carbon nanotubes with uniform temperature control according to claim 3, characterized in that: The air blowing frame (41) is a fixed air blowing plate (411), which is fixedly installed on the connecting frame (432). The fixed air blowing plate (411) has a triangular plate structure. The impact air hole (42) is an oblique air hole (421), which is formed on the side of the fixed air blowing plate (411). The oblique air hole (421) is connected to the inner cavity of the fixed air blowing plate (411), and the connecting air passage (433) is also connected to the inner cavity of the fixed air blowing plate (411).

5. The method for producing carbon nanotubes with uniform temperature control according to claim 3, characterized in that: The air blowing frame (41) is a rotating air blowing pipe (412), which is rotatably mounted on the connecting frame (432). A rotating wheel structure (413) is fixedly connected to the rotating air blowing pipe (412), and the rotating wheel structure (413) rolls in cooperation with the inner wall of the homogenizing reaction vessel (1). The impact air hole (42) is a radial air hole (422), which is a hole distributed radially along the rotating air blowing pipe (412). The tube (412) is configured in multiple groups, and the multiple groups of the rotating air blowing tube (412) are distributed along the circumference of the rotating air blowing tube (412). An arc-shaped baffle (434) is also fixedly connected to the connecting air passage (433). The arc-shaped baffle (434) is located on the side of the rotating air blowing tube (412) away from the inner wall of the homogenizing reaction vessel (1). When the radial air hole (422) is connected to the connecting air passage (433), the connecting air passage (433) is connected to the inner cavity of the rotating air blowing tube (412).

6. A method for producing carbon nanotubes with uniform temperature control according to claim 4 or 5, characterized in that: The bottom end of the lower extension tube (32) is fixedly connected to an extension plate, and a material equalization baffle (33) is rotatably connected to the extension plate. The bottom end of the material equalization baffle (33) is fixedly connected to a counterweight structure (331).

7. The method for producing carbon nanotubes with uniform temperature control according to claim 6, characterized in that: The bottom of the inner cavity of the homogenizing reaction vessel (1) is provided with a gas equalization hood (6), which is located above the air inlet (11). Multiple sets of gas equalization holes (61) are evenly arranged on the gas equalization hood (6).

8. The method for producing carbon nanotubes with uniform temperature control according to claim 7, characterized in that: The discharge port (13) is located on one side of the bottom of the homogenizing reaction vessel (1), and the gas equalization hood (6) is a conical structure. The discharge port (13) is located above the edge of the gas equalization hood (6). A movable plug (62) is provided on the gas equalization hood (6) at the position corresponding to the gas equalization hole (61). The gas equalization hole (61) is slidably engaged with the gas equalization hole (61). The top and bottom of the movable plug (62) are both set as arc structures. The gas equalization hole (61) is provided with an adaptation groove (63) that is compatible with the bottom of the movable plug (62).

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