A system and method for combined preparation of porous carbon and carbon nanotubes

Abstract

The present application provides a kind of porous carbon and carbon nanotube combined preparation system and method, including activation fluidized bed, carbonization fluidized bed and carbon nanotube preparation fluidized bed;Activation fluidized bed is filled with energy carbon carrier, after oxygen and activating gas are imported, energy carbon carrier and oxygen occur combustion heat release, make activation fluidized bed temperature rise, first tail gas formed is imported into carbonization fluidized bed filled with carbon particle precursor, carbon particle precursor is carbonized under the action of high temperature carried by first tail gas, and generates carbide particle, and the second tail gas containing C1-C 30 ;Carbide particle is transported to activation fluidized bed, by controlling the gas flow rate of first gas inlet, so that carbide particle is always in the upper part of activation fluidized bed, and makes carbide particle activate in activating gas, and forms porous carbon particle;Second tail gas enters carbon nanotube preparation fluidized bed, and under the action of nanometer metal catalyst, C1-C 30 In it, is converted into carbon nanotube to realize low-cost co-production of porous carbon and carbon nanotube.

Description

Technical Field

[0001] This invention relates to the field of carbon material preparation systems and methods, and in particular to a system and method for the combined preparation of porous carbon and carbon nanotubes. Background Technology

[0002] Small-particle, high-quality porous carbon has a wide range of applications due to its large specific surface area, adjustable micropores and mesopores, and tunable surface chemical properties. For example, this product is mainly used as porous carbon for silicon-carbon anodes; electrode materials for supercapacitors; promoters for power-type lithium-ion and sodium-ion batteries; carriers for coal chemical catalysts or catalysts for pesticides and fine chemicals; adsorbents for environmental protection; gas separators in coal chemical industry; and for the direct capture of CO2 from the air.

[0003] The preparation steps for porous carbon generally involve using organic precursor particles, followed by high-temperature carbonization and activation. When the carbonized material is reacted with activation gases (water and CO2), the temperature is typically above 800°C. o C, and it is a strongly endothermic reaction. High-temperature engineering heating has always been a huge technical problem, and the comprehensive utilization of high-temperature thermal energy is also an important way to reduce energy consumption and costs. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a system and method for the joint preparation of porous carbon and carbon nanotubes, so as to improve the overall utilization rate of thermal energy in the porous carbon preparation process and the further resource conversion rate of carbonization tail gas.

[0005] The specific details of the invention are as follows:

[0006] In a first aspect, the present invention provides a system for the joint preparation of porous carbon and carbon nanotubes, comprising: an activated fluidized bed, a carbonization fluidized bed connected to the activated fluidized bed, and a carbon nanotube preparation fluidized bed connected to the carbonization fluidized bed;

[0007] The bottom of the activated fluidized bed is filled with an energy-supplying carbon carrier and is provided with a first gas inlet for introducing oxygen and activation gas. The energy-supplying carbon carrier reacts with oxygen to generate heat through combustion, thereby raising the temperature inside the activated fluidized bed to 850-1000 ℃.

[0008] A first solid transport channel and a first gas transport channel are provided between the activated fluidized bed and the carbonized fluidized bed. The carbonized fluidized bed is filled with carbon particle precursors. The first tail gas in the activated fluidized bed is transported to the carbonized fluidized bed through the first gas transport channel. Under the high temperature carried by the first tail gas, the carbon particle precursors undergo carbonization to generate carbonized particles and C1-C-containing particles. 30 The second exhaust gas;

[0009] The carbonized particles are transported to the activated fluidized bed through the first solid transport channel. By controlling the inlet gas flow rate of the first gas inlet, the carbonized particles are kept in the upper middle part of the activated fluidized bed. Under the action of the activated gas, the carbonized particles complete the activation treatment to obtain the porous carbon particle material.

[0010] A second gas transport channel is provided between the carbon nanotube preparation fluidized bed and the carbonization fluidized bed. The second exhaust gas enters the carbon nanotube preparation fluidized bed through the second gas transport channel. The C1-C in the second exhaust gas... 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

[0011] Optionally, the activated fluidized bed and the carbonized fluidized bed undergo heat transfer through the first gas transmission channel, so that the temperature of the carbonized fluidized bed is 700-900 ℃;

[0012] The carbonization fluidized bed and the carbon nanotube preparation fluidized bed undergo heat transfer through the second gas transmission channel, so that the temperature of the carbon nanotube preparation fluidized bed is 700-850 ℃.

[0013] Optionally, a third gas transmission channel is provided between the activated fluidized bed and the carbon nanotube preparation fluidized bed. The third tail gas generated in the carbon nanotube preparation fluidized bed is transported to the activated fluidized bed through the third gas transmission channel and used as activation gas / combustion energy supply.

[0014] Optionally, a pressurizing device is provided on the third gas transmission channel, and the third exhaust gas is pressurized by the pressurizing device and then transported to the activated fluidized bed.

[0015] In a second aspect, the present invention provides a method for the combined preparation of porous carbon and carbon nanotubes, the method being applicable to the system described in any one of claims 1-4 above, the method comprising:

[0016] An energy-supplying carbon carrier is loaded into an activated fluidized bed, a carbon particle precursor is filled into a carbonized fluidized bed, and a nano-metal catalyst is filled into a carbon nanotube-prepared fluidized bed. Oxygen and activation gas are introduced into the combustion zone of the activated fluidized bed through a first gas inlet. The energy-supplying carbon carrier and oxygen undergo combustion and release heat, making the temperature in the activated fluidized bed 850-1000 ℃.

[0017] The first tail gas generated in the activated fluidized bed is introduced into the carbonization fluidized bed through the first gas transmission channel. Under the high temperature carried by the first tail gas, the carbon particle precursor undergoes carbonization to generate carbonized particles, as well as C1-C. 30 The second exhaust gas;

[0018] The carbonized particles are fed into the activated fluidized bed through the first solid transport channel. By controlling the inlet gas flow rate of the first gas inlet, the carbonized particles are kept in the upper middle part of the activated fluidized bed. Under the action of the activated gas, the carbonized particles complete the activation process to obtain the porous carbon particle material.

[0019] The second exhaust gas is transported to the carbon nanotube preparation fluidized bed via the second gas transmission channel, and the C1-C in the second exhaust gas are... 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

[0020] Optionally, the preparation method further includes: conveying the third tail gas generated in the carbon nanotube preparation fluidized bed to the combustion zone of the activated fluidized bed via a third transmission channel, and using it as an activation gas / combustion energy supply.

[0021] Optionally, the preparation method further includes: the third exhaust gas is pressurized and then transported to the combustion zone of the activated fluidized bed via a third transmission channel to be used as activation gas / combustion energy supply.

[0022] Optionally, the particle size of the energy-supplying carbon carrier is larger than the particle size of the carbon particles.

[0023] Optionally, the amount of oxygen introduced into the activated fluidized bed, after being used for combustion and heat generation by the energy-supplying carbon carrier, shall have a residual oxygen volume concentration of no more than 0.5%.

[0024] Optionally, the nano-metal catalyst comprises an active component and a support, wherein the active component accounts for 20%-50% by mass, and the active component is selected from one or more of iron, cobalt, nickel, platinum, molybdenum, tungsten, copper and manganese;

[0025] The carrier is one or more of aluminum oxide, silicon oxide, and magnesium oxide.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] This invention provides a system for the joint preparation of porous carbon and carbon nanotubes, comprising: an activated fluidized bed, a carbonization fluidized bed connected to the activated fluidized bed, and a carbon nanotube preparation fluidized bed connected to the carbonization fluidized bed; the bottom of the activated fluidized bed is filled with an energy-supplying carbon carrier and is provided with a first gas inlet for introducing oxygen and an activation gas; the energy-supplying carbon carrier and oxygen undergo combustion and exothermic reaction, raising the temperature inside the activated fluidized bed to 850-1000 ℃; a first solid transport channel and a first gas transport channel are provided between the activated fluidized bed and the carbonization fluidized bed; the carbonization fluidized bed is filled with carbon particle precursors; a first tail gas from the activated fluidized bed is transported to the carbonization fluidized bed through the first gas transport channel; the carbon particle precursors undergo carbonization under the high temperature carried by the first tail gas, generating carbonized particles and C1-C... 30 The second exhaust gas; the carbonized particles are transported to the activated fluidized bed via the first solid transport channel. By controlling the inlet gas flow rate of the first gas inlet, the carbonized particles are kept in the upper middle part of the activated fluidized bed, and the carbonized particles are activated under the action of the activating gas to obtain the porous carbon particle material; a second gas transport channel is provided between the carbon nanotube preparation fluidized bed and the carbonization fluidized bed. The second exhaust gas enters the carbon nanotube preparation fluidized bed through the second gas transport channel. The C1-C in the second exhaust gas... 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

[0028] The preparation system provided by this invention can simultaneously realize the carbonization of carbon particle precursors, the activation of carbonized particles, and the further resource conversion of carbonization tail gas, achieving balanced energy supply and overall utilization, and improving thermal energy utilization. The activated fluidized bed not only serves as a device for activating carbonized particles, but also provides the required thermal energy for the operation of the entire system. Moreover, the activated fluidized bed adopts a self-heating fluidized bed (combustion-powered carbon carrier for heating), and the fluidized bed structure is simple, easy to maintain, and effectively reduces the system manufacturing cost. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 A schematic diagram of the structure of the porous carbon and carbon nanotube co-preparation system provided in an embodiment of the present invention is shown;

[0031] Figure 2A flowchart of the method for jointly preparing porous carbon and carbon nanotubes provided in an embodiment of the present invention is shown. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention. Furthermore, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of the present invention.

[0033] Specific experimental steps or conditions are not specified in the embodiments; they can be performed according to the conventional experimental steps or conditions described in the prior art. Reagents and other instruments used, unless otherwise specified, are all commercially available conventional reagent products. Furthermore, the accompanying drawings are merely illustrative diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0034] Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of this specification.

[0035] In the description of this invention, it should be understood that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0036] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] In a first aspect, the present invention provides a system for the joint preparation of porous carbon and carbon nanotubes. Figure 1 A schematic diagram of the structure of the porous carbon and carbon nanotube co-preparation system provided in an embodiment of the present invention is shown. See also Figure 1The system includes: an activated fluidized bed 1, a carbonized fluidized bed 2 connected to the activated fluidized bed 1, and a carbon nanotube preparation fluidized bed 3 connected to the carbonized fluidized bed 2; the bottom of the activated fluidized bed 1 is filled with an energy-supplying carbon carrier and is provided with a first gas inlet 4 for introducing oxygen and activation gas; the energy-supplying carbon carrier and oxygen undergo combustion and exothermic reaction, raising the temperature inside the activated fluidized bed to 850-1000 ℃; a first solid transport channel 5 and a first gas transport channel 7 are provided between the activated fluidized bed 1 and the carbonized fluidized bed 2; the carbonized fluidized bed 2 is filled with carbon particle precursors; the first tail gas in the activated fluidized bed 1 is transported to the carbonized fluidized bed 2 through the first gas transport channel 7; the carbon particle precursors undergo carbonization under the high temperature carried by the first tail gas, generating carbonized particles and C1-C... 30 The second tail gas; the carbonized particles are transported to the activated fluidized bed 1 via the first solid transport channel 5. By controlling the inlet gas flow rate of the first gas inlet 4, the carbonized particles are kept in the upper middle part of the activated fluidized bed 1, and the carbonized particles are activated under the action of the activating gas to obtain the porous carbon particle material; a second gas transport channel 8 is provided between the carbon nanotube preparation fluidized bed 3 and the carbonization fluidized bed 2. The second tail gas enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8. The C1-C in the second tail gas 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

[0038] See Figure 1 In this invention, the activated fluidized bed 1 is a self-heating fluidized bed that generates heat by burning the carbon carrier to power the system. Compared with fluidized beds with a large number of electrically heated structures, the self-heating fluidized bed has a simple structure and can effectively reduce the manufacturing cost of the device and maintenance costs. It should be noted that the combustion of the energy-supplying carbon carrier and the activation of the carbon particles are both completed within the activated fluidized bed 1. In this invention, the activated fluidized bed 1 can be divided into a combustion zone and an activation zone. The combustion zone is located at the bottom of the activated fluidized bed and is filled with the energy-supplying carbon carrier, which provides thermal energy to the preparation system through combustion. The activation zone is located in the upper middle part of the activated fluidized bed and is used to receive the carbon particles transported through the first solid transport channel 5, so that the carbon particles are activated under the action of the activation gas to obtain porous carbon particle material. This division is mainly achieved by controlling the inlet flow rate of the first gas inlet 4 so that the carbon particles are always in the upper middle part of the activated fluidized bed (activation zone), and the energy-supplying carbon carrier is located at the bottom of the activated fluidized bed (with a sufficiently large particle size, unaffected by the airflow), thereby avoiding the loss of carbon particles due to combustion.

[0039] Furthermore, the combustion of the energy-supplying carbon carrier requires the consumption of oxygen, while the activation of carbon particles requires strict control of the oxygen content introduced into the activated fluidized bed 1 to reduce the oxidation / combustion loss of carbon particles at high temperatures; the airflow (including oxygen and activation gases (such as CO2, H2O)) from the first gas inlet 4 first comes into full contact with the energy-supplying carbon carrier in the combustion zone, where the oxygen participates in the combustion reaction and is consumed and removed, and the remaining gas (first tail gas) is heated and reaches the activation zone along the airflow direction to consume carbon particles for activation treatment and to supply energy to the carbonized fluidized bed 2.

[0040] See also Figure 1 The first tail gas generated in the activated fluidized bed 1 is transported to the carbonization fluidized bed 2 via the first gas transmission channel 7, serving as the fluidizing gas. The heat energy carried by the first tail gas also powers the carbonization of the carbon particle precursor. The carbonized particles generated in the carbonization fluidized bed 2 are transported to the upper middle part (activation zone) of the activated fluidized bed 1 via the first solid transmission channel 5. Under the action of the activation gas, the carbonized particles are activated, resulting in porous carbon particle material. This porous carbon particle material is discharged through the first product outlet 6. The combustion reaction of the energy-supplying carbon carrier with oxygen is exothermic, while the activation reaction of the carbonized particles is endothermic. Therefore, the activated fluidized bed 1 can simultaneously undergo combustion reactions involving oxygen and endothermic reactions involving activation gas, achieving self-heating equilibrium in the activated fluidized bed 1.

[0041] In this invention, the heat required for the carbonization of the carbon particle precursor in the carbonization fluidized bed 2 is provided by the activated fluidized bed 1. In the initial stage of preparation, preheated oxygen is introduced into the activated fluidized bed 1 to power the combustion reaction between the carbon support and oxygen, rapidly increasing the temperature within the activated fluidized bed. Further activation gas is introduced, and the oxygen flow rate is controlled to maintain temperature equilibrium within the activated fluidized bed. The gas accumulated in the activated fluidized bed 1 (the first tail gas), after being heated, serves as a fluidizing medium and directly enters the carbonization fluidized bed, ensuring full contact with the carbon particle precursor and providing the necessary temperature for its carbonization into carbonized particles. The carbonized particles return to the activated fluidized bed 1 via the first solid transport channel for further activation treatment. The high temperature carried by the second tail gas generated during carbonization, after entering the carbon nanotube preparation fluidized bed 3, promotes the oxidation of C1-C particles under the action of a catalyst. 30 It is transformed into carbon nanotubes.

[0042] Furthermore, the carbonized particles activated in the activated fluidized bed 1 are supplied by the carbonization fluidized bed 2, which is used to carbonize the carbon particle precursor at high temperature to form carbonized particles; simultaneously, the carbonization process generates C1-C... 30 The exhaust gas (second exhaust gas) further enters the carbon nanotube preparation fluidized bed 3, where, under the action of the nano-metal catalyst, the C1-C in the exhaust gas...30 It is transformed into carbon nanotubes.

[0043] See Figure 1 Oxygen introduced through the first gas inlet 4 of the activated fluidized bed 1 undergoes a combustion reaction with the energy-supplying carbon carrier, generating gases such as CO, CO2, and H2O. These gases mix with the activation gases (H2O and CO2) and the CO and H2 gases generated during the activation process, forming a first tail gas that enters the carbonized fluidized bed 2 through the first gas transmission channel 7. This tail gas is used as the fluidizing gas for the carbonized fluidized bed 2. Furthermore, the carbon particle precursors in the carbonized fluidized bed 2 undergo carbonization under the residual heat of the first tail gas, forming carbonized particles and C1-C-containing particles. 30 The second exhaust gas also carries a large amount of residual heat; therefore, the second exhaust gas is directly transported to the carbon nanotube preparation fluidized bed 3 via the second gas transmission channel 8, so that the C1-C in the second exhaust gas... 30 Under the action of nano-metal catalysts, it is converted into carbon nanotubes, H2, and CH4, etc. The preparation system provided by this invention effectively utilizes the first tail gas as the fluidizing gas for carbonization fluidized bed 2, and the second tail gas as the fluidizing gas and reaction medium for preparing carbon nanotube fluidized bed 3, thereby improving the waste heat utilization rate and reducing gas usage costs.

[0044] The preparation system provided by this invention can simultaneously realize the carbonization of carbon particle precursors, the activation of carbonized particles, and the further resource conversion of carbonization tail gas, achieving balanced energy supply and overall utilization, and improving thermal energy utilization rate. The activated fluidized bed not only serves as a device for activating carbonized particles, but also provides the required thermal energy for the operation of the entire system. Moreover, the activated fluidized bed adopts a self-heating fluidized bed (combustion-powered carbon carrier for heating), and the fluidized bed structure is simple, easy to maintain, and effectively reduces the system manufacturing cost.

[0045] It should be noted that by controlling the oxygen flux entering the activated fluidized bed, most of the oxygen is consumed in the combustion reaction with the energy-supplying carbon carrier. When the oxygen reaches the carbon particle stacking / aggregation zone, the volume concentration of oxygen is no more than 0.5%, so as to ensure that the dominant medium for the activation reaction of the carbon particles is H2O, CO2 and trace amounts of oxygen. The oxygen content entering the first gas inlet is matched with the heat required for the activation reaction of the carbon particles in the activated fluidized bed 1.

[0046] In some embodiments, the activated fluidized bed and the carbonized fluidized bed undergo heat transfer through the first gas transmission channel, so that the temperature of the carbonized fluidized bed is 700-900 ℃; the carbonized fluidized bed and the carbon nanotube preparation fluidized bed undergo heat transfer through the second gas transmission channel, so that the temperature of the carbon nanotube preparation fluidized bed is 700-850 ℃.

[0047] This invention is based on the fact that the carbonization temperature of the carbon particle precursor is lower than the temperature required for the activation of the carbon particles, C1-C 30 The temperature required for conversion into carbon nanotubes is lower than the carbonization temperature required for the carbon particle precursor. Therefore, the heat required for the carbonization of the carbon particle precursor in the carbonization fluidized bed 2 can be provided by the activated fluidized bed 1. After introducing an appropriate amount of oxygen and activation gas into the activated fluidized bed 1, the energy-supplying carbon carrier reacts with oxygen to undergo a combustion reaction, causing the temperature in the activated fluidized bed to rise rapidly. Once the temperature reaches 850-1000 ℃, the gas in the activated fluidized bed 1 (the first tail gas) is used as a fluidizing medium and introduced into the carbonization fluidized bed 2 through the first gas transmission channel 7. This maintains the temperature of the carbonization fluidized bed at 700-900 ℃, meeting the temperature requirements for the carbon particle precursor carbonization. Meanwhile, the high temperature carried by the second tail gas produced during carbonization enters the carbon nanotube preparation fluidized bed 3 through the second gas transmission channel 7, maintaining the temperature of the carbon nanotube preparation fluidized bed 3 at 700-850 ℃. Under the action of a catalyst, this promotes the carbonization of C1-C... 30 It is converted into carbon nanotubes. Thus, the preparation system provided by this invention can be powered by the combustion of the energy-supplying carbon support in the activated fluidized bed 1.

[0048] In some embodiments, a third gas transmission channel 12 is provided between the activated fluidized bed 1 and the carbon nanotube preparation fluidized bed 3. The third tail gas generated in the carbon nanotube preparation fluidized bed 3 is transported to the combustion zone of the activated fluidized bed 1 through the third gas transmission channel 12 and used as activation gas / combustion energy supply.

[0049] See Figure 1 In the fluidized bed preparation of carbon nanotubes, C1-C 30 Under the action of the nano-metal catalyst, it is converted into carbon nanotubes and generates H2 and CH4. The carbon nanotubes are discharged through the second product outlet 11. The remaining gas components (third tail gas) in the carbon nanotube preparation fluidized bed 3 also include the remaining unreacted activation gas. Therefore, by setting the third gas transmission channel 12, the third tail gas generated in the carbon nanotube preparation fluidized bed 3 is transported to the combustion zone of the activated fluidized bed 1 for secondary utilization. CO, CH4, H2, etc. in it can react with the energy-supplying carbon carrier to generate heat through combustion, and H2O and CO2 are used for the activation reaction of carbon particles, further improving the resource utilization rate.

[0050] As a preferred example, a pressurizing device is provided on the third gas transmission channel 12. The third tail gas generated in the carbon nanotube preparation fluidized bed 3 is discharged through the third gas transmission channel 12, pressurized, and then sent into the activation fluidized bed 1 through the first gas inlet 4 to meet the pressure requirements of the activation reaction.

[0051] Secondly, the present invention provides a method for the combined preparation of porous carbon and carbon nanotubes, the method being applicable to the preparation system described in the first aspect above. Figure 2 A flowchart of the method for co-preparing porous carbon and carbon nanotubes provided in an embodiment of the present invention is shown, as follows: Figure 2 As shown, the method includes:

[0052] S1. An energy-supplying carbon carrier is loaded into an activated fluidized bed, a carbon particle precursor is filled into a carbonized fluidized bed, and a nano-metal catalyst is filled into a carbon nanotube preparation fluidized bed. Oxygen and activation gas are introduced into the combustion zone of the activated fluidized bed through a first gas inlet. The energy-supplying carbon carrier and oxygen undergo combustion and release heat, so that the temperature in the activated fluidized bed is 850-1000 ℃.

[0053] S2. The first tail gas generated in the activated fluidized bed is introduced into the carbonization fluidized bed through the first gas transmission channel. Under the high temperature carried by the first tail gas, the carbon particle precursor undergoes carbonization to generate carbonized particles, as well as C1-C. 30 The second exhaust gas;

[0054] S3. The carbonized particles are fed into the activated fluidized bed through the first solid transport channel. By controlling the inlet flow rate of the first gas inlet, the carbonized particles are always positioned in the upper middle part of the activated fluidized bed, and the carbonized particles are activated under the action of the activating gas to obtain the porous carbon particle material.

[0055] S4. The second exhaust gas is transported to the carbon nanotube preparation fluidized bed via the second gas transmission channel, and the C1-C in the second exhaust gas are dissolved. 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

[0056] In practice, the activated fluidized bed is a self-heating fluidized bed, which generates heat by burning the energy-supplying carbon carrier to power the system. Compared with fluidized beds with a large number of electrically heated structures, the self-heating fluidized bed has a simple structure and can effectively reduce the manufacturing cost and maintenance cost of the device. The energy-supplying carbon carrier is filled into the activated fluidized bed and deposited at the bottom of the activated fluidized bed. In the initial stage of preparation, preheated oxygen is introduced into the activated fluidized bed through the first gas inlet. The energy-supplying carbon carrier first reacts with oxygen to produce a large amount of heat, which rapidly raises the temperature in the activated fluidized bed to 850-1000℃. Activating gas is then introduced, and the oxygen supply is controlled to maintain the temperature balance in the activated fluidized bed. The gas entering the activated fluidized bed (the first tail gas) is heated and then used as a fluidizing medium. It enters the carbonization fluidized bed through the first gas transmission channel, making full contact with the carbon particle precursors and providing the required temperature for the carbonization of the carbon particle precursors into carbonized particles. The generated carbonized particles are returned to the activated fluidized bed via the first solid transport channel, where they continue to be activated by the activating gas. Meanwhile, the high-temperature secondary tail gas generated during the carbonization reaction in the carbonization fluidized bed can, after entering the carbon nanotube preparation fluidized bed, be further activated by the packed catalyst, promoting the oxidation of C1-C... 30 It is transformed into carbon nanotubes.

[0057] In this embodiment of the invention, the inlet gas flow rate of the first gas inlet is controlled so that the energy-supplying carbon carrier is located at the bottom of the activated fluidized bed (with a sufficiently large particle size, unaffected by the airflow). The carbon particles entering the activated fluidized bed are always located in the upper middle part of the activated fluidized bed (activation region) due to their small particle size and light weight. Under the action of the activating gas, the carbon particles are activated to obtain porous carbon particle material, thus avoiding the loss of carbon particles due to combustion.

[0058] Furthermore, the combustion of the energy-supplying carbon carrier requires the consumption of oxygen, while the activation of carbon particles requires strict control of the oxygen content introduced into the activated fluidized bed to reduce the oxidation / combustion loss of carbon particles at high temperatures. The airflow (including oxygen and activation gases such as CO2 and H2O) from the first gas inlet first comes into full contact with the energy-supplying carbon carrier in the combustion zone. The oxygen in the gas participates in the combustion reaction and is consumed and removed. The remaining gas (first tail gas) is heated and flows along the airflow direction through the carbon particles for activation treatment and consumption, as well as to supply energy to the carbonized fluidized bed.

[0059] The method for jointly preparing porous carbon and carbon nanotubes provided by this invention maintains the operating temperature of the activated fluidized bed through combustion of oxygen and an energy-supplying carbon carrier, while minimizing the loss of carbon particles and porous carbon products used in the activation process. By utilizing the waste heat of the tail gas in the activated fluidized bed and using the tail gas formed during the carbonization process as a reaction medium to generate carbon nanotubes, the heating problems of the three endothermic reactions and the toxic and odorous problems of the carbonization tail gas are solved. This simplifies the fluidized bed structure and provides advantages such as low energy consumption, continuous operation, high yield, and cleanliness, effectively saving preparation costs, achieving balanced energy supply and overall utilization, and improving thermal energy utilization efficiency.

[0060] It should be noted that the energy carrier is continuously consumed in the activated fluidized bed. The energy carrier can be replenished periodically according to the temperature of the activated fluidized bed to maintain the self-heating balance of the activated fluidized bed. Similarly, the carbon particle precursor can also be replenished after the carbon particles have been converted and transferred to the activated fluidized bed, so that the preparation process can be carried out continuously.

[0061] It should also be noted that the composition of the nano-metal catalyst includes an active component and a support. The active component accounts for 20%-50% by mass and is selected from one or more of iron, cobalt, nickel, platinum, molybdenum, tungsten, copper and manganese. The support is one or more of alumina, silicon oxide and magnesium oxide. The carbon particle precursor can be selected from organic particles with a particle size of no more than 200 μm. The main components of the organic particles are carbon, hydrogen and oxygen, including but not limited to starch, lignin, cellulose, nutshell, resin, polyester, asphalt, etc.

[0062] It should also be noted that the carbon nanotubes prepared by the embodiments of the present invention have a diameter of 0.4-100 nm; and the specific surface area of ​​the obtained porous carbon is 1400-2600 m². 2 / g, the ratio of micropores to mesopores is 1:5~5:1.

[0063] In some embodiments, the preparation method further includes: conveying a third tail gas generated in the carbon nanotube preparation fluidized bed to the combustion zone of the activated fluidized bed via a third transmission channel, and using it as an activation gas / combustion energy supply.

[0064] In the fluidized bed preparation of carbon nanotubes, C1-C 30Under the action of the nano-metal catalyst, it is converted into carbon nanotubes and generates H2 and CH4. The carbon nanotubes are discharged through the second product outlet. The remaining gas components (third tail gas) in the carbon nanotube preparation fluidized bed also include the remaining unreacted activation gas. Therefore, the third tail gas generated in the carbon nanotube preparation fluidized bed is transported to the combustion zone of the activated fluidized bed through the third gas transmission channel for secondary utilization. CO, CH4, H2 and other components can react with the energy-supplying carbon carrier to generate heat through combustion, and H2O and CO2 are used for the activation reaction of carbon particles, further improving the resource utilization rate.

[0065] As a preferred example, the third exhaust gas, after being pressurized, is transported to the combustion zone of the activated fluidized bed via a third transmission channel to be used as activation gas / combustion energy supply to meet the pressure requirements of the activation reaction.

[0066] In some embodiments, the particle size of the energy-supplying carbon carrier is larger than the particle size of the carbon particles.

[0067] As a preferred example, the energy-supplying carbon carrier is selected from carbon particles of 0.3-0.5 mm (ash content less than 5 ppm), and the carbon particle size is controlled at 2-200 μm.

[0068] In some embodiments, the amount of oxygen introduced into the activated fluidized bed, after being used for combustion and heat generation by the energy-supplying carbon carrier, results in a residual oxygen volume concentration of no more than 0.5%.

[0069] In practice, by controlling the oxygen content entering the first gas inlet, the amount of oxygen remaining after the combustion reaction of the oxygen with the energy-supplying carbon carrier is not greater than 0.5% in volume when it reaches the carbon particle stacking / aggregation area, so as to ensure that the dominant medium for the activation reaction of the carbon particles is H2O, CO2 and trace oxygen; the oxygen content entering the first gas inlet is matched with the heat required for the activation reaction of the carbon particles in the activated fluidized bed 1.

[0070] To enable those skilled in the art to better understand the present invention, the following embodiments will be used to provide a detailed description of the system and method for the combined preparation of porous carbon and carbon nanotubes according to the present invention.

[0071] The following examples are all in Figure 1 The process is carried out in the system shown, wherein the activated fluidized bed 1 is filled with an energy-supplying carbon carrier, the carbonized fluidized bed 2 is filled with a carbon particle precursor, and the carbon nanotube preparation fluidized bed 3 is filled with a nano-metal catalyst.

[0072] Example 1

[0073] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.3-0.35 mm, ash content less than 5 ppm) react with the oxygen, causing the activated fluidized bed 1 to heat up rapidly. Activating gas of 50% H2O and 50% CO2 is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature in the activated fluidized bed 1 at 950 ℃ and the pressure at 0.1 MPa. The combustion gas (first tail gas) contains no oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7, where it is used as the fluidizing gas.

[0074] The carbon particle precursor (starch, carbon, hydrogen, and oxygen contents of 45%, 6%, and 49%, respectively, with a particle size of 2-50 μm) in the carbonization fluidized bed 2 is transformed into carbonized particles (carbon content greater than 97%, particle size of 2-50 μm) under the action of fluidizing gas at 770℃ for 3 hours. The carbonized particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbonized particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, and the mixing ratio of the two is less than 0.5%; and the volume concentration of oxygen when it reaches the particle stacking area for the activation preparation of porous carbon is 0.001%. Under the action of activation gas, the carbonized particles are activated in the activation fluidized bed 1. After an activation time of 8 hours, the activated porous carbon product (2600 m³) is obtained. 2 / g, with a micropore to mesopore ratio of 1:5 and a particle size of 2-50μm) is discharged through the first product outlet 6.

[0075] The carbonized tail gas (second tail gas) produced in carbonized fluidized bed 2 contains C1-C 30 Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 40% Fe, 10% Mo; support: 50% silicon dioxide), the reaction medium reacts at 700℃, converting the organic matter into carbon nanotubes (5-20 nm in diameter), CH4, and H2. After 12 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0076] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After being pressurized, it is used as the fluidizing gas and combustion medium (incorporating H2O or CO2) to activate the fluidized bed 1.

[0077] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0078] Example 2

[0079] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.3-0.35 mm, ash content less than 5 ppm) react with the oxygen, causing the activated fluidized bed 1 to heat up rapidly. H2O activation gas is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature of the activated fluidized bed 1 at 850℃ and the pressure at 1 MPa. The combustion gas (first tail gas) contains no oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7, where it is used as the fluidizing gas.

[0080] The carbon particle precursors (lignin and cellulose, with carbon, hydrogen, and oxygen contents of 55%, 6%, and 39%, respectively, and a particle size of 20-40 μm) in the carbonization fluidized bed 2 are transformed into carbon particles (carbon content greater than 97%, particle size of 20-40 μm) under the action of fluidizing gas at 800℃ for 0.5 hours. The carbon particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbon particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, and the mixing ratio of the two is less than 0.5%; and the volume concentration of oxygen when it reaches the particle stacking area for the activation preparation of porous carbon is 0.5%. Under the action of activation gas, the carbon particles are activated in the activation fluidized bed 1. After an activation time of 2 hours, the activated porous carbon product (1400 m³) is obtained. 2 / g, with a micropore to mesopore ratio of 5:1 and a particle size of 20-40 μm) is discharged through the first product outlet 6.

[0081] The carbonized tail gas (second tail gas) produced in carbonized fluidized bed 2 contains C1-C 30 Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 40% Co, 10% Cu; support: 50% alumina), the reaction medium reacts at 760℃, converting the organic matter into carbon nanotubes (0.4-3 nm in diameter), CH4, and H2. After 2 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0082] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After being pressurized, it is used as the fluidizing gas and combustion medium (integrated with H2O) to activate the fluidized bed 1.

[0083] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0084] Example 3

[0085] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.4-0.5 mm, ash content less than 5 ppm) react with the oxygen in an oxidation reaction, causing the activated fluidized bed 1 to heat up rapidly. Activating gas of 90% H2O and 10% CO2 is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature of the activated fluidized bed 1 at 950℃ and the pressure at 0.5 MPa. The combustion gas (first tail gas) contains no oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7, where it is used as the fluidizing gas.

[0086] The carbon particle precursors (nutshells, carbon, hydrogen, and oxygen contents of 60%, 6%, and 34%, with a particle size of 2-15 μm) in the carbonization fluidized bed 2 are transformed into carbonized particles (carbon content greater than 97%, particle size of 2-15 μm) under the action of fluidizing gas at 750℃ for 2 hours. The carbonized particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbonized particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, and the mixing ratio of the two is less than 0.5%; and the volume concentration of oxygen when it reaches the particle stacking area for the activation preparation of porous carbon is 0.01%. Under the action of the activation gas, the carbonized particles are activated in the activation fluidized bed 1. After an activation time of 4 hours, the activated porous carbon product (2200m³) is obtained. 2 / g, with a micropore to mesopore ratio of 1:1 and a particle size of 2-15μm) is discharged through the first product outlet 6.

[0087] The carbonized tail gas (second tail gas) produced in carbonized fluidized bed 2 contains C1-C 30Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 37% Ni, 2% Mn, 1% Pt; support: 60% magnesium oxide), the reaction medium reacts at 700℃, converting the organic matter into carbon nanotubes (10-100 nm in diameter), CH4, and H2. After 6 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0088] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After being pressurized, it is used as the fluidizing gas and combustion medium (incorporating H2O or CO2) to activate the fluidized bed 1.

[0089] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0090] Example 4

[0091] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.3-0.4 mm, ash content less than 5 ppm) react with the oxygen in an oxidation reaction, causing the activated fluidized bed 1 to heat up rapidly. H2O activation gas is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature of the activated fluidized bed 1 at 960℃ and the pressure at 0.6 MPa. The combustion gas (first tail gas) does not contain oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7 to be used as the fluidizing gas.

[0092] The carbon particle precursors (phenolic resin and epoxy resin, with carbon, hydrogen, and oxygen contents of 45%, 13%, and 33%, respectively, and particle size of 2-60 μm) in the carbonization fluidized bed 2 are transformed into carbonized particles (carbon content greater than 97%, particle size of 2-60 μm) under the action of fluidizing gas at 800℃ for 2 hours. The carbonized particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbonized particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, and the mixing ratio of the two is less than 0.5%; and the volume concentration of oxygen when it reaches the particle stacking area for the activated porous carbon preparation is 0.45%. Under the action of activation gas, the carbonized particles are activated in the activation fluidized bed 1. After an activation time of 4 hours, the activated porous carbon product (1600 m³) is obtained. 2 / g, with a micropore to mesopore ratio of 3:1 and a particle size of 2-60μm) is discharged through the first product outlet 6.

[0093] The second tail gas produced in the carbonized fluidized bed 2 contains C1-C 30 Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 45% Ni, 5% Mo; support: 50% silicon dioxide), the reaction medium reacts at 700℃, converting the organic matter into carbon nanotubes (1-10 nm in diameter), CH4, and H2. After 8 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0094] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After being pressurized, it is used as the fluidizing gas and combustion medium (incorporating H2O or CO2) to activate the fluidized bed 1.

[0095] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0096] Example 5

[0097] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.3-0.35 mm, ash content less than 5 ppm) react with the oxygen, causing the activated fluidized bed 1 to heat up rapidly. CO2 activation gas is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature of the activated fluidized bed 1 at 920 ℃ and the pressure at 0.8 MPa. The combustion gas (first tail gas) does not contain oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7 to be used as the fluidizing gas.

[0098] The carbon particle precursor (polyester, carbon, hydrogen, and oxygen contents of 62.5%, 4.2%, and 33.3%, respectively, with a particle size of 100-200 μm) in the carbonization fluidized bed 2 is transformed into carbonized particles (carbon content greater than 97%, particle size of 100-200 μm) under the action of fluidizing gas at 900℃ for 1 hour. The carbonized particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbonized particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, with a mixing ratio of less than 0.5%; and the oxygen volume concentration is 0.35% when it reaches the particle stacking area for the activated porous carbon preparation. Under the action of the activation gas, the carbonized particles are activated in the activation fluidized bed 1. After an activation time of 2 hours, the activated porous carbon product (2000 m³) is obtained. 2 / g, with a micropore to mesopore ratio of 1:3 and a particle size of 100-200μm) is discharged through the first product outlet 6.

[0099] The second tail gas produced in the carbonized fluidized bed 2 contains C1-C 30 Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 30% Fe, 3% Mo, 7% Mn; support: 60% magnesium oxide), the reaction medium reacts at 850 °C, converting the organic matter into carbon nanotubes (5-20 nm in diameter), CH4, and H2. After 2-12 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0100] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After pressurization, it is used as the fluidizing gas and combustion medium (integrated with H2O or CO2) to activate the fluidized bed 1.

[0101] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0102] Example 6

[0103] Preheated oxygen-containing gas is introduced into the activated fluidized bed 1 through the first gas inlet 4. The energy carrier carbon particles (particle size 0.3-0.5 mm, ash content less than 5 ppm) react with the oxygen, causing the activated fluidized bed 1 to heat up rapidly. CO2 activation gas is then continuously introduced into the activated fluidized bed 1 through the first gas inlet 4, controlling the oxygen flow rate to maintain the temperature of the activated fluidized bed 1 at 1000 ℃ and the pressure at 0.3 MPa. The combustion gas (first tail gas) does not contain oxygen and enters the carbonized fluidized bed 2 through the first gas transmission channel 7, where it is used as the fluidizing gas.

[0104] The carbon particle precursors (asphaltite particles, carbon, hydrogen, and oxygen contents of 95%, 4.9%, and 0.1%, respectively, with a particle size of 2-10 μm) in the carbonization fluidized bed 2 are transformed into carbonized particles (carbon content greater than 97%, particle size of 1-10 μm) under the action of fluidizing gas at 850℃ for 1.5 hours. The carbonized particles are then fed into the activation fluidized bed 1 via the first solid transport channel 5. Due to the particle size difference, under the action of gas velocity, the carbonized particles are located in the upper part of the fluidized bed; the energy carrier carbon particles are located in the lower part of the fluidized bed, with a mixing ratio of less than 0.5%; and the volume concentration of oxygen when it reaches the particle stacking area for the activation preparation of porous carbon is 0.25%. Under the action of the activation gas, the carbonized particles are activated in the activation fluidized bed 1. After an activation time of 6 hours, the activated porous carbon product (1800 m³) is obtained. 2 / g, with a micropore to mesopore ratio of 1:5~5:1 and a particle size of 1-10μm) is discharged through the first product outlet 6.

[0105] The second tail gas produced in the carbonized fluidized bed 2 contains C1-C 30 Organic matter, along with H2O, H2, CO2, CO, etc., enters the carbon nanotube preparation fluidized bed 3 via the second gas transport channel 8, serving as the fluidizing gas and reaction medium. Under the action of a nano-metal catalyst (active metals: 39% Fe, 1% Mo, 1% W; support: 59% alumina), it reacts with the reaction medium at 820℃, converting the organic matter into carbon nanotubes (5-20 nm in diameter), CH4, and H2. After 2-12 hours of reaction, the carbon nanotubes are discharged from the second product outlet 11.

[0106] The third tail gas from the carbon nanotube fluidized bed 3 exits the carbon nanotube fluidized bed 3 through the third gas transmission channel 12. After pressurization, it is used as the fluidizing gas and combustion medium (integrated with H2O or CO2) to activate the fluidized bed 1.

[0107] The energy carrier carbon particles are continuously consumed in fluidized bed 1. They are replenished periodically according to the temperature of fluidized bed 1 to maintain the activated fluidized bed 1 in self-thermal equilibrium (the combustion of carbon, CO, CH4, H2, and oxygen is an exothermic reaction; the activation reaction of carbon with H2O and CO2 is an endothermic reaction). The above steps are repeated to make the process continuous.

[0108] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0109] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0110] The above provides a detailed description of the system and method for the combined preparation of porous carbon and carbon nanotubes provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A system for the joint preparation of porous carbon and carbon nanotubes, characterized in that, include: An activated fluidized bed, a carbonized fluidized bed connected to the activated fluidized bed, and a carbon nanotube-based fluidized bed connected to the carbonized fluidized bed; The bottom of the activated fluidized bed is filled with an energy-supplying carbon carrier and is provided with a first gas inlet for introducing oxygen and activation gas. The energy-supplying carbon carrier reacts with oxygen to generate heat through combustion, thereby raising the temperature inside the activated fluidized bed to 850-1000 ℃. A first solid transport channel and a first gas transport channel are provided between the activated fluidized bed and the carbonized fluidized bed. The carbonized fluidized bed is filled with carbon particle precursors. The first tail gas in the activated fluidized bed is transported to the carbonized fluidized bed through the first gas transport channel. Under the high temperature carried by the first tail gas, the carbon particle precursors undergo carbonization to generate carbonized particles and C1-C-containing particles. 30 The second exhaust gas; The carbonized particles are transported to the activated fluidized bed through the first solid transport channel. By controlling the inlet gas flow rate of the first gas inlet, the carbonized particles are kept in the upper middle part of the activated fluidized bed. Under the action of the activated gas, the carbonized particles complete the activation treatment to obtain the porous carbon particle material. A second gas transport channel is provided between the carbon nanotube preparation fluidized bed and the carbonization fluidized bed. The second exhaust gas enters the carbon nanotube preparation fluidized bed through the second gas transport channel. The C1-C in the second exhaust gas... 30 Under the action of nano-metal catalysts, it is transformed into carbon nanotubes; The activated fluidized bed and the carbonized fluidized bed undergo heat transfer through the first gas transmission channel, so that the temperature of the carbonized fluidized bed is 700-900 ℃; The carbonization fluidized bed and the carbon nanotube preparation fluidized bed are heat-transferred through the second gas transmission channel, so that the temperature of the carbon nanotube preparation fluidized bed is 700-850 ℃; A third gas transmission channel is provided between the activated fluidized bed and the carbon nanotube preparation fluidized bed. The third tail gas generated in the carbon nanotube preparation fluidized bed is transported to the activated fluidized bed through the third gas transmission channel and used as activation gas / combustion energy supply.

2. The porous carbon and carbon nanotube co-preparation system according to claim 1, characterized in that, A pressurizing device is provided on the third gas transmission channel. After the third exhaust gas is pressurized by the pressurizing device, it is transported to the activated fluidized bed.

3. A method for jointly preparing porous carbon and carbon nanotubes, characterized in that, The method is applicable to the system described in any one of claims 1-2 above, and the method includes: An energy-supplying carbon carrier is loaded into an activated fluidized bed, a carbon particle precursor is filled into a carbonized fluidized bed, and a nano-metal catalyst is filled into a carbon nanotube-prepared fluidized bed. Oxygen and activation gas are introduced into the combustion zone of the activated fluidized bed through a first gas inlet. The energy-supplying carbon carrier and oxygen undergo combustion and release heat, making the temperature in the activated fluidized bed 850-1000 ℃. The first tail gas generated in the activated fluidized bed is introduced into the carbonization fluidized bed through the first gas transmission channel. Under the high temperature carried by the first tail gas, the carbon particle precursor undergoes carbonization to generate carbonized particles, as well as C1-C. 30 The second exhaust gas; The carbonized particles are fed into the activated fluidized bed through the first solid transport channel. By controlling the inlet gas flow rate of the first gas inlet, the carbonized particles are kept in the upper middle part of the activated fluidized bed. Under the action of the activated gas, the carbonized particles complete the activation process to obtain the porous carbon particle material. The second exhaust gas is transported to the carbon nanotube preparation fluidized bed via the second gas transmission channel, and the C1-C in the second exhaust gas are... 30 Under the action of a nano-metal catalyst, it is transformed into carbon nanotubes.

4. The method for jointly preparing porous carbon and carbon nanotubes according to claim 3, characterized in that, The preparation method further includes: transporting the third tail gas generated in the carbon nanotube preparation fluidized bed to the combustion zone of the activated fluidized bed via a third transmission channel, and using it as activation gas / combustion energy supply.

5. The method for jointly preparing porous carbon and carbon nanotubes according to claim 3, characterized in that, The preparation method further includes: the third tail gas is pressurized and then transported to the combustion zone of the activated fluidized bed through the third transmission channel to be used as activation gas / combustion energy supply.

6. The method for jointly preparing porous carbon and carbon nanotubes according to claim 3, characterized in that, The particle size of the energy-supplying carbon carrier is larger than the particle size of the carbon particles.

7. The method for jointly preparing porous carbon and carbon nanotubes according to claim 3, characterized in that, The amount of oxygen introduced into the activated fluidized bed, after being used for combustion and heat generation by the energy-supplying carbon carrier, leaves a residual oxygen volume concentration of no more than 0.5%.

8. The method for jointly preparing porous carbon and carbon nanotubes according to claim 3, characterized in that, The nano-metal catalyst comprises an active component and a support, wherein the active component accounts for 20%-50% by mass, and the active component is selected from one or more of iron, cobalt, nickel, platinum, molybdenum, tungsten, copper and manganese. The carrier is one or more of aluminum oxide, silicon oxide, and magnesium oxide.

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