A high-conductive pitch-based activated carbon and its preparation method

Abstract

This invention relates to a highly conductive asphalt-based activated carbon and its preparation method. The method involves uniformly mixing asphalt with one or more of the following polymers: polyvinylidene chloride, polyvinyl chloride, and polyacrylonitrile. The mixture is then subjected to steps including curing, crosslinking, activation, washing, drying, and heat treatment to obtain the highly conductive activated carbon. Compared to traditional asphalt-based activated carbon preparation methods, the polymers in this method undergo a strong polycondensation and crosslinking reaction with asphalt molecules, forming a highly crosslinked polycyclic aromatic hydrocarbon carbon precursor. This highly crosslinked macromolecular structure inhibits the melting and severe decomposition of asphalt during carbonization, promotes the formation of a good conductive network, and significantly improves the specific surface area, conductivity, and yield of the activated carbon.

Description

Technical Field

[0001] This invention relates to the field of new materials, specifically to an activated carbon material and its preparation method. Background Technology

[0002] Supercapacitors are a new type of energy storage device that falls between traditional capacitors and batteries, combining the high power density of traditional capacitors with the high energy density of batteries. Electrode materials are a crucial component of supercapacitors and a key factor influencing their electrochemical performance. Activated carbon is the most widely used electrode material; its double-layer energy storage mechanism enables supercapacitors to exhibit rapid charging and discharging, high power density, and long lifespan. Activated carbon's outstanding advantages include its well-developed internal pore structure, large specific surface area, and excellent electrochemical stability. With increasing application requirements, preparing activated carbon with high specific surface area has become one of the main methods to improve its capacitance performance. However, the specific capacitance of activated carbon does not simply increase with increasing specific surface area. The well-developed porous structure disrupts the conductive network, significantly reducing the conductivity of the activated carbon. This makes it difficult to simultaneously achieve both porous structure and conductivity, and the energy storage active sites cannot be fully utilized.

[0003] To address the aforementioned issues, researchers have combined activated carbon with other conductive carbon materials (such as graphene nanosheets, conductive carbon black, and carbon nanotubes). For example, patent ZL2013100314451 discloses a method for preparing activated carbon / carbon nanotube composite aerogel electrode materials. Using phenolic resin as the carbon source, the activated carbon / carbon nanotube composite aerogel electrode material is prepared in situ using supercritical drying or freeze-drying methods. The electrode material prepared by this method exhibits a specific capacitance as high as 390 F / g at room temperature. Patent CN107331523B discloses an activated carbon / carbon nanotube / graphene composite material, its preparation method, and its applications. This invention utilizes the effective composite of activated carbon, carbon nanotubes, and graphene to prepare a three-dimensional composite material, fully leveraging the advantages of graphene and carbon nanotubes' large specific surface area and high electrical conductivity. Patent CN108516548A uses medium-temperature coal tar pitch as raw material and performs Soxhlet extraction with pyridine solution to obtain pitch-pyridine solution. Carbon black is then added to this solution to prepare pitch-based spherical activated carbon for use in supercapacitors. Patent CN106115693B discloses a method for preparing composite phenolic resin-based activated carbon. This method involves attaching phenolic resin to graphene oxide sheets during curing, followed by carbonization and alkali activation to obtain activated carbon with a large specific surface area. Graphene forms a well-conducting network within the activated carbon.

[0004] Furthermore, researchers have also enhanced the conductivity of activated carbon by subjecting it to secondary high-temperature treatment to promote the growth of graphite microcrystals and increase the degree of graphitization. For example, patent CN105197910A pre-carbonizes king oyster mushrooms in a high-temperature furnace, then dissolves them in a solvent containing an activator, freeze-dries them, and then places the resulting intermediate product into a high-temperature furnace for secondary heat treatment. The heat-treated product is then treated with an acid solution and vacuum dried to obtain porous nanocarbon materials. Activated carbon prepared by this method has good pore structure and conductivity. Patent CN106082213B discloses a composite petroleum coke-based activated carbon and its preparation method. This method utilizes the reduction of graphene oxide to graphene to form a conductive network, and then performs high-temperature heat treatment to reduce its surface functional groups, preparing activated carbon with a large specific surface area and low internal resistance. Patent CN101290837A uses microporous zeolite molecular sieves as templates and gaseous acetylene, methane, or ethylene as carbon sources to prepare activated carbon, which is then subjected to high-temperature heat treatment at 1000–1600℃ to adjust its surface properties. This yields activated carbon with low surface hydrophilicity and low oxygen content. Patent CN109422265B discloses a high-temperature modification method for activated carbon raw materials, which decomposes oxygen-containing groups on the surface, partially graphitizes them, and improves the conductivity of the activated carbon.

[0005] However, methods for constructing conductive networks using composite conductive carbon suffer from increased costs, large size of the composite conductive carbon materials, and poor structural compatibility. Methods for improving conductivity through high-temperature secondary treatment of activated carbon also have the problem of reducing the specific surface area of ​​the activated carbon at excessively high temperatures. Therefore, a more efficient and cost-effective method is needed to prepare activated carbon that possesses both a porous structure and high conductivity.

[0006] Asphalt has natural advantages in the preparation of highly conductive carbon materials: its molecular structure is rich in polycyclic aromatic hydrocarbons, which form a graphite-like structure during heat treatment, resulting in high intrinsic conductivity. Furthermore, asphalt is not affected by seasonal changes, is inexpensive, and has a large production volume. Asphalt-based activated carbon has a porous structure, providing a large surface area to accommodate charges, while also exhibiting high intrinsic conductivity to support rapid charging and discharging. However, the thermoplastic nature of asphalt makes it prone to liquid-phase carbonization when used to construct carbon materials, leading to difficulties in controlling the microstructure and structural properties of the carbon materials. Currently, pre-oxygenation of asphalt molecules in air introduces oxygen-containing functional groups, and the cross-linking reaction between these functional groups allows the asphalt molecules to form a relatively stable structure. Patent CN103803550A discloses a method for preparing asphalt-based activated carbon, which involves pulverizing asphalt, coking it to form raw coke, pulverizing the raw coke, mixing the raw coke powder with potassium hydroxide, activating, washing, and drying to obtain activated carbon with high mesopore content and high effective surface utilization. Patent CN102491320B discloses an ultra-high specific surface area pitch-based activated carbon and its preparation method. Pitch and rosin are used as raw materials, and ultra-high specific surface area pitch-based activated carbon is prepared through hot-melt stirring, high-temperature pyrolysis, pre-oxidation, and activation processes. Patent CN109110758A describes pitch-based activated carbon obtained through multiple steps including mixing, air oxidation, carbonization, and steam activation. Patent CN109019591A describes pitch-based activated carbon obtained through mixing, spheroidizing, air oxidation, liquid-phase oxidation, carbonization, and activation. Patent CN110697705B uses coal tar pitch as raw material, incorporates activators and pore-forming agents, and directly obtains activated carbon with a multi-level porous structure through a one-step carbonization-activation method. Patent CN1224034A discloses a method for preparing asphalt-based spherical activated carbon. This method involves mixing asphalt, organometallic compounds, and aromatic solvents at high temperature in a high-pressure autoclave to first obtain asphalt raw materials containing metal particles suitable for preparing asphalt balls. These are then sphericalized via emulsification, followed by infusibility, carbonization, and activation treatment to obtain asphalt-based spherical activated carbon with well-developed mesopores. Patent CN111348648A discloses a process for preparing asphalt-based molded activated carbon. Molten deoiled asphalt is reacted with air in a reaction tower to produce oxidized asphalt. The oxidized asphalt, water, and binder are then mixed, kneaded using a mixer, extruded into strips using an extruder, and pre-oxidized, carbonized, and activated in a rotary kneader to finally obtain activated carbon.

[0007] However, the asphalt stabilization methods mentioned in the aforementioned patents all suffer from cumbersome procedures, high costs, and low efficiency. Specifically, the liquid-phase oxidation method suffers from harsh reaction conditions, severe pollution, and a low safety factor, affecting the conductivity and residual carbon rate of asphalt-based activated carbon. The air oxidation method suffers from poor controllability, time consumption, and low efficiency. Therefore, a method with simple processes, mild operating conditions, and low production costs is needed for asphalt stabilization. Patent CN107904699A uses medium-temperature coal tar pitch and polyvinylpyrrolidone as raw materials, and prepares coal tar pitch-based carbon fibers through spinning, pre-oxidation, and carbonization. These fibers, when used as electrodes in supercapacitors, exhibit advantages such as high specific capacitance and good rate performance. Patent CN106958053A uses petroleum coke and polyacrylonitrile as raw materials, and prepares porous petroleum coke-based carbon fibers through spinning, pre-oxidation, and carbonization. These fibers, when used as electrode materials in supercapacitors, exhibit excellent capacitance performance and avoid the use of binders. The polymers in the aforementioned patents exhibit cross-linking properties, cross-linking small asphalt molecules to form large, three-dimensional molecules, which are then electrospinned to prepare carbon nanofibers with cross-linked structures. This demonstrates that a strong polycondensation and cross-linking reaction between polymers and asphalt molecules can be utilized to form highly cross-linked polycyclic aromatic hydrocarbon carbon precursors, thereby achieving the purpose of stabilizing asphalt. However, the polymers in these patents primarily function as carbon matrix and structure-directing agents, with the polymer as the main precursor and asphalt added in small amounts as a conductive agent. Furthermore, the material prepared is not essentially asphalt-based activated carbon, but rather nanofiber fabric, with a low specific surface area, typically below 700 m². 2 g -1 .

[0008] The purpose of this invention is to provide a method for preparing highly conductive asphalt activated carbon. Compared with previously disclosed patents and literature, the method proposed in this patent involves adding a small amount of cross-linking polymer to asphalt, causing it to undergo a strong condensation and cross-linking reaction with asphalt molecules to form a highly cross-linked polycyclic aromatic hydrocarbon carbon precursor. This precursor is then subjected to pre-oxidation treatment to stabilize the asphalt. In this invention, the polymer acts as a cross-linking agent. This invention has the advantages of simple process, mild operating conditions, and low production cost. It significantly shortens the pre-oxidation treatment time, inhibits asphalt melting, and achieves efficient structural stabilization. Furthermore, due to the cross-linking between asphalt molecules and the formation of pores between polymers, the resulting activated carbon exhibits high yield, high specific surface area, high porosity, and high conductivity, demonstrating excellent supercapacitor energy storage performance. Summary of the Invention

[0009] This invention provides a method for preparing highly conductive asphalt-based activated carbon. The method involves adding a polymer to asphalt, where the two are completely bonded together to form a unified conductive network. Furthermore, the polymer can undergo a strong polycondensation and cross-linking reaction with asphalt molecules to form a highly cross-linked polycyclic aromatic hydrocarbon carbon precursor. Simultaneously, the precursor is stabilized using simple air oxidation. Activated carbon with both a large specific surface area and high conductivity is prepared through activation. This method is achieved through the following technical solutions:

[0010] (1) Dissolve the asphalt and polymer in an organic solvent and mix thoroughly;

[0011] (2) Evaporate the well-mixed solution to dryness and grind it;

[0012] (3) Crosslinking and curing of the mixed materials;

[0013] (4) Activate the cured material;

[0014] (5) Wash and dry the activated material;

[0015] (6) The washed and dried materials are subjected to high-temperature heat treatment;

[0016] Furthermore, the asphalt used in step (1) is one or more of coal tar pitch, petroleum asphalt, and modified asphalt with a softening point between 120 and 270°C.

[0017] Furthermore, the polymer used in step (1) is one or a combination of several of polyvinylidene chloride (PVDC), polyacrylonitrile (PAN), and polyvinyl chloride (PVC).

[0018] Furthermore, the content of the polymer used in step (1) accounts for 10% to 40% of the total mass of the mixture, and the content of the asphalt used accounts for 60% to 90% of the total mass of the mixture. Each 1g of mixture needs to be dissolved in 50 to 100mL of organic solvent and thoroughly mixed by stirring or ultrasound.

[0019] Furthermore, the organic solvent used in step (1) is one or a combination of N,N-dimethylformamide (DMF), toluene (MB), and tetrahydrofuran (THF).

[0020] Further, in step (3), the mixture processed in step (2) is crosslinked and cured by pre-oxidation treatment in an air atmosphere. The pre-oxidation heating program is as follows: the temperature is increased to 150-350°C at a heating rate of 2-8°C / min and held at this temperature for 3-8 hours.

[0021] Furthermore, step (4) involves mixing the cross-linked and cured raw materials from step (3) at a ratio of 1:20 g / mL.-1 The activator is dispersed in a mixed solution of water and ethanol in a certain proportion. The activator is added according to the mass ratio of activator to raw material of 1:0.5 to 1:3 to obtain a mixed solution. After soaking for 8 to 10 hours, the solution is evaporated to dryness. The dried product is heated at 150°C for 2 hours. Finally, the powder sample is ground until uniform and activated under an inert atmosphere.

[0022] Furthermore, in step (4), the activation treatment involves a heating rate of 3–5 °C / min, an activation temperature of 500–900 °C, and a holding time of 1–4 h.

[0023] Further, in step (5), the activated sample from step (4) is dissolved in deionized water, neutralized with hydrochloric acid to pH 5-7, and the temperature is controlled at 25-70°C for 2-10 hours.

[0024] Further, the sample from step (5) is washed, and the washed sample is dried at 110°C for 3 to 8 hours.

[0025] Furthermore, the sample from step (6) is subjected to high-temperature heat treatment at a temperature of 700–2000℃ for a holding time of 0.5–5 hours. This step may or may not be performed depending on the final product requirements.

[0026] Beneficial technical effects of the present invention:

[0027] (1) This method introduces a high molecular polymer into asphalt, which undergoes a strong polycondensation and cross-linking reaction with asphalt molecules to form a highly cross-linked polycyclic aromatic hydrocarbon carbon precursor. Therefore, activated carbon with a good pore size distribution can be formed through activation.

[0028] (2) The highly cross-linked macromolecular structure can inhibit the melting and severe decomposition of asphalt during carbonization, which is crucial for the pore structure regulation of asphalt-based activated carbon. It also helps the activator to approach and etch less stable regions to form pores and significantly improves the yield of activated carbon.

[0029] (3) The activated carbon prepared by this method has a good conductive network and high strength, and excellent electrochemical performance.

[0030] (4) Compared with the traditional asphalt curing process, this method can quickly cure asphalt with low energy consumption; and the raw materials used are all common industrial raw materials, so the overall preparation cost is low. Attached Figure Description

[0031] Figure 1 This is a flowchart of a method for preparing highly conductive pitch-based activated carbon. Detailed Implementation

[0032] The present invention will be further illustrated by the following description of embodiments, but the present invention is not limited to the following embodiments.

[0033] Example 1

[0034] 9g of coal tar pitch with a softening point of 170℃ and 1g of polyvinylidene chloride (PVDC) were dissolved in 500mL of N,N-dimethylformamide (DMF). After thorough mixing, the mixture was heated to dryness to obtain the asphalt-PVDC composite material. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 150℃ at a rate of 2℃ / min and held at this temperature for 3 hours to obtain the cured asphalt-PVDC composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9, and 30g of activator KOH was added and mixed thoroughly to obtain a mixed solution. After being fully impregnated for 8 hours, the solution was evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the obtained powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by heating from room temperature to 700℃ at a rate of 3℃ / min and holding for 3 hours. After activation, the material was crushed and dissolved in deionized water, neutralized with hydrochloric acid to pH 5, and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours. After heat treatment at 1100℃ for 1 hour, highly conductive activated carbon was obtained.

[0035] Example 2

[0036] 8g of coal tar pitch with a softening point of 230℃ and 2g of polyvinylidene chloride (PVDC) were dissolved in 500mL of N,N-dimethylformamide (DMF). After thorough mixing, the mixture was heated to dryness to obtain the asphalt-PVDC composite material. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 200℃ at a rate of 3℃ / min and held at this temperature for 2 hours to obtain the cured asphalt-PVDC composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9. 30g of activator KOH was added and mixed thoroughly to obtain a mixed solution. The solution was thoroughly impregnated for 8 hours and then evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the obtained powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by heating from room temperature to 800℃ at a rate of 5℃ / min and holding for 2 hours. After activation, the material was crushed and dissolved in deionized water. It was neutralized with hydrochloric acid to pH 5 and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours. After heat treatment at 1300℃ for 1 hour, highly conductive activated carbon was obtained.

[0037] Example 3

[0038] 9g of petroleum asphalt with a softening point of 170℃ and 1g of polyacrylonitrile (PAN) were dissolved in 500mL of tetrahydrofuran (THF). After thorough mixing and heating to dryness, asphalt-PAN composite material was obtained. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 150℃ at a rate of 2℃ / min and held at this temperature for 3 hours to obtain the cured asphalt-PAN composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9. 30g of activator KOH was added and mixed thoroughly to obtain a mixed solution. The solution was thoroughly impregnated for 8 hours and then evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the obtained powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by increasing the temperature from room temperature to 700℃ at a rate of 5℃ / min and holding for 3 hours. After activation, the material was crushed and dissolved in deionized water. It was neutralized with hydrochloric acid to pH 5 and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours to obtain highly conductive activated carbon.

[0039] Example 4

[0040] 8g of petroleum asphalt with a softening point of 230℃ and 2g of polyacrylonitrile (PAN) were dissolved in 500mL of tetrahydrofuran (THF). After thorough mixing and heating to dryness, asphalt-PAN composite material was obtained. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 200℃ at a rate of 2℃ / min and held at this temperature for 2 hours to obtain the cured asphalt-PAN composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9. 30g of activator KOH was added and mixed thoroughly to obtain a mixed solution. The solution was thoroughly impregnated for 8 hours and then evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by increasing the temperature from room temperature to 800℃ at a rate of 5℃ / min and holding for 2 hours. After activation, the material was crushed and dissolved in deionized water. It was neutralized with hydrochloric acid to pH 5 and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours to obtain highly conductive activated carbon.

[0041] Example 5

[0042] 8g of coal tar pitch with a softening point of 190℃ and 2g of polyvinyl chloride (PVC) were dissolved in 500mL of toluene (MB). After thorough mixing, the mixture was heated to dryness to obtain asphalt-PVC composite material. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 150℃ at a rate of 2℃ / min and held at this temperature for 4 hours to obtain the cured asphalt-PVC composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9. 30g of activator LiOH was added and mixed thoroughly to obtain a mixed solution. The solution was thoroughly impregnated for 8 hours and then evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by increasing the temperature from room temperature to 800℃ at a rate of 5℃ / min and holding for 2 hours. After activation, the material was crushed and dissolved in deionized water. It was neutralized with hydrochloric acid to pH 5 and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours. After heat treatment at 1100℃ for 1 hour, highly conductive activated carbon was obtained.

[0043] Example 6

[0044] 6g of coal tar pitch with a softening point of 230℃ and 4g of polyvinyl chloride (PVC) were dissolved in 500mL of toluene (MB). After thorough mixing, the mixture was heated to dryness to obtain the asphalt-PVC composite material. The material was placed in a furnace and cured in an air atmosphere. The heating program was as follows: the temperature was increased to 200℃ at a rate of 2℃ / min and held at this temperature for 2 hours to obtain the cured asphalt-PVC composite material. 10g of the cured composite material was dispersed in 200mL of a mixed solution of water and ethanol with a volume ratio of 1:9. 30g of activator LiOH was added and mixed thoroughly to obtain a mixed solution. The solution was thoroughly impregnated for 8 hours and then evaporated to dryness. The dried material was heated at 150℃ for 2 hours. Finally, the powder sample was ground until uniform and placed in a ceramic boat in a horizontal tube furnace. The furnace was activated in a nitrogen atmosphere by heating from room temperature to 800℃ at a rate of 5℃ / min and holding for 2 hours. After activation, the material was crushed and dissolved in deionized water. It was neutralized with hydrochloric acid to pH 5 and the temperature was controlled at 25℃. The mixture was stirred for 10 hours, washed until neutral, and then dried in an oven at 110℃ for 8 hours. After heat treatment at 1100℃ for 1 hour, highly conductive activated carbon was obtained.

[0045] Table 1 Examples

[0046]

[0047]

[0048] The above description is merely a preferred embodiment of the present invention and is not limited to the invention. It should be noted that those skilled in the art can make other equivalent improvements based on the technical teachings provided by the present invention, all of which can achieve the purpose of the present invention and should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing highly conductive pitch-based activated carbon, characterized in that, The preparation method specifically includes the following steps: dissolving and thoroughly mixing asphalt powder and polymer in an organic solvent to form a molecularly homogeneous mixture, followed by drying and grinding to obtain precursor A powder. The asphalt is one or a mixture of coal tar pitch, petroleum asphalt, and modified asphalt with a softening point between 120 and 270°C. The polymer is one or a combination of polyvinylidene chloride (PVDC), polyacrylonitrile (PAN), and polyvinyl chloride (PVC). Precursor A is cross-linked and cured to obtain precursor B. Precursor B is mixed with an activator to obtain precursor C, followed by activation treatment to obtain sample A. The activated material is crushed, washed, dried, and heat-treated to obtain the highly conductive asphalt-based activated carbon.

2. The method for preparing highly conductive pitch-based activated carbon according to claim 1, characterized in that, The organic solvent is one or a combination of N,N-dimethylformamide (DMF), toluene (MB), and tetrahydrofuran (THF); the polymer accounts for 10% to 40% of the mixture by mass, the asphalt accounts for 60% to 90% of the mixture, and each 1g of mixture needs to be dissolved in 50 to 100mL of organic solvent and thoroughly mixed by stirring or ultrasound.

3. The method for preparing highly conductive pitch-based activated carbon according to claim 1, characterized in that, The cross-linking curing process involves pre-oxidation in air to introduce oxygen-containing functional groups and achieve stabilization. The pre-oxidation heating program involves heating to 150–350°C at a rate of 2–8°C / min and holding at that temperature for 3–8 hours. The activation step involves mixing precursor B at a ratio of 1:20 g / mL. -1 The precursor B is dispersed in a mixed solution of water and ethanol. Activator is added at a mass ratio of 1:0.5 to 1:3 to obtain a mixed solution. After soaking for 8 to 10 hours, the solution is evaporated to dryness. The dried product is placed in an oven and heated at 150°C for 2 hours. Finally, the powder sample is ground until homogeneous to obtain precursor C. The activator is a conventional alkali metal activator, including but not limited to LiOH, KOH, CsOH, KHCO3, and K2CO3. Precursor C is then activated under an inert atmosphere to obtain sample A. The activation temperature is 500 to 900°C, and the holding time is 1 to 4 hours. The activation atmosphere is a conventional inert atmosphere, including but not limited to N2 and Ar atmospheres.

4. The method for preparing highly conductive pitch-based activated carbon according to claim 1, characterized in that, The heat treatment temperature is 700–2000℃, and the holding time is 0.5–5h; this step may or may not be implemented depending on the final product requirements.

5. The highly conductive pitch-based activated carbon according to any one of claims 1-4, characterized in that, The highly conductive asphalt-based activated carbon possesses both a large specific surface area and high powder conductivity, with a specific surface area ≥1500 m². 2 g -1 Powder conductivity ≥600 S cm -1 .

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