Active carbon material for vehicle and preparation method and application thereof

Abstract

The application provides a kind of activated carbon material for vehicle and its preparation method and application, the preparation method includes the following steps: polyhydroxy phenolic compound, polyaldehyde compound, first catalyst, macromolecular surfactant, metal salt and second catalyst are mixed and reacted, to obtain reaction product;The obtained reaction product is sequentially subjected to solid-liquid separation, molding, freezing and pyrolysis, to obtain the activated carbon material.The preparation method provided by the application is low in cost, and avoids the shortcomings that the basic properties of traditional activated carbon raw materials are uncontrollable;The preparation process is directly shaped and reactivated, solving the pore blocking effect caused by the addition of binder in the traditional activated carbon molding process;The pore size distribution of the activated carbon material is precisely controlled, and the adsorption and desorption effect of the activated carbon material is improved;Heat storage medium is introduced, and the adsorption capacity of the activated carbon material is improved by reasonably utilizing the adsorption and desorption heat effect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of environmental functional materials, and relates to an activated carbon material, in particular to a vehicle activated carbon material and a preparation method and application thereof. BACKGROUND

[0002] The automobile carbon tank is an important environmental protection device for adsorbing and storing gasoline vapor. When the automobile is in the off state, when the ambient temperature rises, the gasoline in the fuel tank will evaporate to form vapor, and if these vapors are directly discharged into the atmosphere, they will pollute the atmospheric environment. Therefore, the activated carbon in the automobile carbon tank is used to adsorb gasoline vapor, thereby preventing gasoline vapor from polluting the atmosphere. When the automobile is started again, the activated carbon in the carbon tank is purged with air to release the adsorbed gasoline vapor, so that the engine can burn more efficiently.

[0003] CN102698724A, CN107570112A, CN113753891A and other disclosed patents provide a preparation method of activated carbon in a vehicle carbon tank. In the preparation method of the activated carbon provided by the prior art, wood chips, wood powder and other wooden raw materials are usually used as preparation raw materials, zinc chloride, phosphoric acid and other activators are added for activation and hole expansion, and a reinforcing binder is added, and the activated carbon product is prepared by a certain molding process to improve the adsorption capacity and wear resistance of the activated carbon.

[0004] A large number of studies have shown that when activated carbon adsorbs gasoline vapor, not all pores can play a role, only mesopores with a pore size of 2-6 nm can effectively participate in the adsorption and desorption of gasoline vapor. Therefore, it is an important optimization direction for the activated carbon preparation process to design the pore structure and obtain mesoporous activated carbon with a narrow pore size distribution; in addition, during the adsorption process of gasoline, adsorption heat is released. In the traditional carbon tank, the single filling of activated carbon material makes it difficult to effectively transfer the adsorption heat, and the temperature of the activated carbon rises, thereby reducing the adsorption capacity of the material, so solving the influence of adsorption heat on the adsorption process is also an important direction for improving the performance of activated carbon material.

[0005] In addition, the binder added in the traditional activated carbon molding process can give the molded columnar carbon a certain mechanical strength, but it also greatly changes the pore structure of the carbon powder, thereby affecting the adsorption and desorption performance of the activated carbon. Therefore, it is of great significance for the activated carbon industry to develop a new molding process that maximizes the retention of the pore structure of the activated carbon. SUMMARY

[0006] To address the shortcomings of existing technologies, the present invention aims to provide an activated carbon material for automobiles, its preparation method, and its application. This method precisely controls the pore size distribution of the activated carbon material, introduces metal salts as a heat storage medium, and directly shapes and reactivates the material during preparation, resulting in a mesoporous columnar activated carbon material with a narrow pore size distribution and integrated heat storage.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a method for preparing activated carbon material, the method comprising the following steps:

[0009] (1) Mix and react a polyhydroxyphenol compound, a polyaldehyde compound, a first catalyst, a polymeric surfactant, a metal salt, and a second catalyst to obtain the reaction product;

[0010] (2) The reaction products obtained in step (1) are subjected to solid-liquid separation, molding, freezing and pyrolysis in sequence to obtain the activated carbon material.

[0011] The preparation method provided by this invention uses chemical raw materials to replace traditional activated carbon raw materials such as biomass and charcoal, resulting in low cost. It also avoids the drawbacks of uncontrollable basic properties of traditional activated carbon raw materials, precisely controlling the pore size distribution of the activated carbon and introducing metal salts as a heat storage medium to improve the adsorption capacity and adsorption-desorption efficiency of the activated carbon material. Simultaneously, the preparation process of the activated carbon precursor involves direct molding followed by carbonization and activation, solving the problem of pore blockage caused by the addition of binders in the traditional columnar activated carbon molding process, and the resulting reduction in adsorption-desorption performance, thus greatly preserving the pore structure of the activated carbon.

[0012] Preferably, the polyhydroxyphenolic compound in step (1) includes any one or a combination of at least two of resorcinol, catechol, hydroquinone, pyrogallol, or pyrogallol. Typical but non-limiting combinations include combinations of resorcinol and catechol, combinations of hydroquinone and pyrogallol, combinations of resorcinol and pyrogallol, combinations of pyrogallol and pyrogallol, combinations of catechol, hydroquinone, and pyrogallol, or combinations of resorcinol, catechol, hydroquinone, pyrogallol, and pyrogallol.

[0013] Preferably, the polyaldehyde compound in step (1) includes any one or a combination of at least two of glyoxal, malondialdehyde, succinaldehyde, glutaraldehyde, terephthalaldehyde, o-phthalaldehyde, isophthalaldehyde, or trimellitaldehyde. Typical but non-limiting combinations include combinations of glyoxal and malondialdehyde, succinaldehyde and glutaraldehyde, isophthalaldehyde and trimellitaldehyde, glyoxal and terephthalaldehyde, malondialdehyde and o-phthalaldehyde, succinaldehyde and isophthalaldehyde, glutaraldehyde and trimellitaldehyde, glyoxal, succinaldehyde and terephthalaldehyde, or malondialdehyde, glutaraldehyde and trimellitaldehyde.

[0014] Preferably, the molar ratio of the polyhydroxyphenolic compound to the polyaldehyde compound in step (1) is 1:(0.5-5), for example, it can be 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5 or 1:5, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0015] Preferably, the first catalyst in step (1) comprises any one or a combination of at least two of NH4OH, triethylamine, sodium bicarbonate, or sodium carbonate. Typical but non-limiting combinations include a combination of NH4OH and triethylamine, a combination of triethylamine and sodium bicarbonate, a combination of sodium bicarbonate and sodium carbonate, a combination of NH4OH, triethylamine, and sodium bicarbonate, a combination of triethylamine, sodium bicarbonate, and sodium carbonate, or a combination of NH4OH, triethylamine, sodium bicarbonate, and sodium carbonate.

[0016] Preferably, in step (1), the molar ratio of the first catalyst to the polyhydroxyphenolic compound is 1:(100-500), for example, it can be 1:100, 1:150, 1:200, 1:250, 1:300, 1:350, 1:400, 1:450 or 1:500, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] Preferably, the polymeric surfactant in step (1) includes any one or at least two of F127, P123 or P407. Typical but non-limiting combinations include the combination of F127 and P123, the combination of P123 and P407, the combination of F127 and P407, or the combination of F127, P123 and P407.

[0018] Preferably, the molar ratio of the polymeric surfactant to the polyhydroxyphenolic compound in step (1) is 1:(100-300), for example, it can be 1:100, 1:150, 1:200, 1:250 or 1:300, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] Preferably, the metal salt in step (1) includes any one or at least two combinations of FeCl3, ZnCl2, NiCl2, MgCl2 or CuCl2. Typical but non-limiting combinations include combinations of FeCl3 and ZnCl2, combinations of ZnCl2 and NiCl2, combinations of NiCl2 and MgCl2, combinations of MgCl2 and CuCl2, combinations of FeCl3, ZnCl2 and NiCl2, combinations of NiCl2, MgCl2 and CuCl2, or combinations of FeCl3, ZnCl2, NiCl2, MgCl2 and CuCl2.

[0020] Preferably, the molar ratio of the metal salt to the polyhydroxyphenolic compound in step (1) is 1:(5-20), for example, it can be 1:5, 1:6, 1:8, 1:10, 1:12, 1:14, 1:15, 1:16, 1:18 or 1:20, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the second catalyst in step (1) comprises any one or at least two of hydrochloric acid, sulfuric acid, formic acid or acetic acid, and typical but non-limiting combinations include combinations of hydrochloric acid and sulfuric acid, combinations of sulfuric acid and formic acid, combinations of formic acid and acetic acid, combinations of hydrochloric acid, sulfuric acid and formic acid, combinations of sulfuric acid, formic acid and acetic acid, or combinations of hydrochloric acid, sulfuric acid, formic acid and acetic acid.

[0022] Preferably, in step (1), the molar ratio of the second catalyst to the polyhydroxyphenolic compound is 1:(5-20), for example, it can be 1:5, 1:6, 1:8, 1:10, 1:12, 1:14, 1:15, 1:16, 1:18 or 1:20, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0023] Preferably, the mixing in step (1) is carried out in a solvent medium, for example, the solvent includes deionized water and / or ethanol.

[0024] Preferably, the reaction temperature in step (1) is 60-120°C, for example, it can be 60°C, 70°C, 80°C, 90°C, 100°C, 110°C or 120°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] Preferably, the reaction time in step (1) is 12-36 hours, for example, it can be 12 hours, 14 hours, 15 hours, 16 hours, 18 hours, 20 hours, 22 hours, 24 hours, 25 hours, 26 hours, 28 hours, 30 hours, 32 hours, 34 hours, 35 hours or 36 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0026] Preferably, the freezing temperature in step (2) is between -22°C and -196°C, for example, it can be -22°C, -30°C, -40°C, -50°C, -60°C, -70°C, -80°C, -90°C, -100°C, -110°C, -120°C, -130°C, -140°C, -150°C, -160°C, -170°C, -180°C, -190°C, or -196°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0027] Preferably, the freezing time in step (2) is 2-48h, for example, it can be 2h, 5h, 10h, 15h, 20h, 25h, 30h, 35h, 40h, 45h or 48h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0028] Preferably, the atmosphere for pyrolysis in step (2) includes N2 and / or CO2.

[0029] Preferably, the heating rate of the pyrolysis in step (2) is 1-5℃ / min, for example, it can be 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0030] Preferably, the pyrolysis temperature in step (2) is 800-1600℃, for example, it can be 800℃, 900℃, 1000℃, 1100℃, 1200℃, 1300℃, 1400℃, 1500℃ or 1600℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0031] Preferably, the pyrolysis time in step (2) is 1-2 hours, for example, it can be 1 hour, 1.2 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.8 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0032] In a second aspect, the present invention provides an activated carbon material, which is prepared by the preparation method described in the first aspect.

[0033] The activated carbon material provided by this invention is a cylindrical carbon with a diameter of 2-3 mm and a length of 3-5 mm. This carbon has a narrow pore size distribution, with a pore size range of 1-10 nm, and the pore volume of mesopores with a pore size of 2-6 nm accounts for 50-80% of the total pore volume. This allows for precise control of the pore size distribution of the activated carbon, improving the adsorption and desorption effects and avoiding desorption difficulties caused by excessive micropores. Simultaneously, a metal salt is creatively introduced as a heat storage medium, effectively storing the heat of adsorption during the adsorption process, preventing the activated carbon temperature from rising and increasing the material's adsorption capacity. During desorption, the heat is released, facilitating desorption and reducing external heat input. This rational utilization of the heat effect of adsorption and desorption contributes to energy conservation. Furthermore, the direct molding and subsequent carbonization activation during the preparation of the activated carbon precursor solves the problem of pore blockage caused by the addition of binders in the traditional cylindrical activated carbon molding process, as well as the resulting reduction in adsorption and desorption performance. This greatly preserves the pore structure of the activated carbon and improves the adsorption and desorption performance of the cylindrical carbon.

[0034] Thirdly, the present invention provides an application of the activated carbon material as described in the second aspect, wherein the activated carbon material is used for gasoline vapor adsorption in automotive carbon canisters.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] The preparation method provided by this invention uses chemical raw materials to replace traditional activated carbon raw materials such as biomass and charcoal, resulting in low cost and avoiding the disadvantage of uncontrollable basic properties of traditional activated carbon raw materials. Based on the adsorption characteristics of gasoline, the pore size distribution of the activated carbon material is precisely controlled, so that a large number of pores are distributed in the range of 2-6 nm, thereby improving the adsorption and desorption effect of the activated carbon material. A heat storage medium is introduced to make reasonable use of the adsorption and desorption heat effect and improve the adsorption capacity of the activated carbon material. The activated carbon precursor is directly formed and then carbonized and activated during the preparation process, which solves the problem of pore blockage caused by the addition of binders in the traditional columnar activated carbon forming process, as well as the resulting reduction in adsorption and desorption performance. This method greatly preserves the pore structure of activated carbon and improves the adsorption and desorption performance of columnar carbon. Detailed Implementation

[0037] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0038] Example 1

[0039] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0040] (1) Disperse resorcinol and glyoxal in deionized water at a molar ratio of 1:3, then add sodium bicarbonate as a catalyst. The molar ratio of sodium bicarbonate to resorcinol is 1:200. Stir until completely dissolved.

[0041] (2) Add surfactant F127 to the completely dissolved solution. The molar ratio of F127 to resorcinol is 1:200. Add metal salt FeCl3. The molar ratio of FeCl3 to resorcinol is 1:20. After uniform dispersion, add dilute hydrochloric acid and then transfer to an oven to keep the reaction at 80°C for 24 hours.

[0042] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of 3 mm and a length of 5 mm. Freeze at -22℃ for 48 h, and then transfer it to a freeze dryer for thorough drying.

[0043] (4) The dried sample was pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 800°C at a rate of 1°C / min for 1 hour. The activated carbon material was obtained after the pyrolysis was completed.

[0044] Example 2

[0045] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0046] (1) Disperse catechol, pyrogallol and pyrrolizidine aldehyde in deionized water at a molar ratio of 1:1:5, then add sodium bicarbonate as a catalyst. The molar ratio of sodium bicarbonate to the total amount of the two polyhydroxyphenolic compounds is 1:500. Stir until completely dissolved.

[0047] (2) Add surfactant F127 to the completely dissolved mixture. The molar ratio of F127 to the total amount of the two polyhydroxyphenolic compounds is 1:200. Add ZnCl2. The molar ratio of ZnCl2 to the total amount of the two polyhydroxyphenolic compounds is 1:20. After uniform dispersion, add dilute hydrochloric acid to the mixture and then transfer it to an oven. Keep it at 80°C for 24 hours.

[0048] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of 3 mm and a length of 5 mm. Freeze it at -22℃ for 24 h, and then transfer it to a freeze dryer to dry it thoroughly.

[0049] (4) The dried sample was pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 800°C at a rate of 1°C / min for 1 hour. The activated carbon material was obtained after the pyrolysis was completed.

[0050] Example 3

[0051] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0052] (1) Disperse catechol, resorcinol, pyrogallol, glyoxal, and glutaraldehyde in deionized water at a molar ratio of 1:1:1:6:6, and then add NH4OH as a catalyst. The molar ratio of NH4OH to the total amount of the three polyhydroxyphenolic compounds is 1:300. Stir until completely dissolved.

[0053] (2) Add surfactant F127 to the completely dissolved mixture. The molar ratio of F127 to the total amount of the three polyhydroxyphenolic compounds is 1:200. Add NiCl2. The molar ratio of NiCl2 to the total amount of the three polyhydroxyphenolic compounds is 1:5. After uniform dispersion, add dilute hydrochloric acid to the mixture and then transfer it to an oven. Keep it at 80°C for 24 hours.

[0054] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of 3 mm and a length of 5 mm. Freeze at -22℃ for 24 h, and then transfer it to a freeze dryer for thorough drying.

[0055] (4) The dried sample was further pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 800°C at a rate of 1°C / min for 1 hour. The activated carbon material was obtained after the pyrolysis was completed.

[0056] Example 4

[0057] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0058] (1) Disperse resorcinol and glyoxal in deionized water at a molar ratio of 1:3, then add sodium bicarbonate as a catalyst. The molar ratio of sodium bicarbonate to resorcinol is 1:200. Stir until completely dissolved.

[0059] (2) Add surfactant P123 to the completely dissolved mixture above. The molar ratio of P123 to resorcinol is 1:250. Add MgCl2. The molar ratio of MgCl2 to resorcinol is 1:5. After uniform dispersion, add dilute hydrochloric acid to the mixture and then transfer it to an oven. Keep it at 100°C for 18 hours.

[0060] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of 3 mm and a length of 5 mm. Freeze at -22℃ for 48 h, and then transfer it to a freeze dryer for thorough drying.

[0061] (4) The dried sample was further pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 800°C at a rate of 1°C / min for 1 hour. The activated carbon material was obtained after the pyrolysis was completed.

[0062] Example 5

[0063] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0064] (1) Disperse resorcinol and glyoxal in deionized water at a molar ratio of 1:0.5, then add sodium bicarbonate as a catalyst. The molar ratio of sodium bicarbonate to resorcinol is 1:100. Stir until completely dissolved.

[0065] (2) Add surfactant F127 to the completely dissolved solution. The molar ratio of F127 to resorcinol is 1:100. Add metal salt FeCl3. The molar ratio of FeCl3 to resorcinol is 1:10. After uniform dispersion, add dilute hydrochloric acid and then transfer to an oven to keep it at 60°C for 36 hours to carry out the reaction.

[0066] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of 3 mm and a length of 5 mm. Freeze at -22℃ for 48 h, and then transfer it to a freeze dryer for thorough drying.

[0067] (4) The dried sample was pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 800°C at a rate of 1°C / min for 1 hour. The activated carbon material was obtained after the pyrolysis was completed.

[0068] Example 6

[0069] This embodiment provides a method for preparing activated carbon material, the method comprising the following steps:

[0070] (1) Disperse resorcinol and glyoxal in deionized water at a molar ratio of 1:5, then add sodium bicarbonate as a catalyst. The molar ratio of sodium bicarbonate to resorcinol is 1:500. Stir until completely dissolved.

[0071] (2) Add surfactant F127 to the completely dissolved solution. The molar ratio of F127 to resorcinol is 1:300. Add metal salt FeCl3. The molar ratio of FeCl3 to resorcinol is 1:10. After uniform dispersion, add dilute hydrochloric acid and then transfer to an oven. Keep the reaction at 120°C for 12 hours.

[0072] (3) After the reaction is complete, wash and filter the reaction product thoroughly, retain the filter residue, and use an extrusion device to extrude the product into a cylinder with a diameter of about 3 mm and a length of about 5 mm. Freeze at -22℃ for 48 h, and then transfer it to a freeze dryer to dry thoroughly.

[0073] (4) The dried sample was pyrolyzed in a tube furnace under N2 atmosphere, and the temperature was increased to 1600℃ at a heating rate of 1℃ / min for 1h. The activated carbon material was obtained after the pyrolysis was completed.

[0074] Example 7

[0075] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the metal salt used in step (2) is replaced with CuCl2 in equal amounts, and the rest is the same as in Example 1.

[0076] Example 8

[0077] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the freezing temperature of step (3) is controlled at -196℃ and the freezing time is 2h. The rest are the same as in Example 1.

[0078] Example 9

[0079] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the pyrolysis atmosphere in step (4) is controlled to be CO2, and the rest is the same as in Example 1.

[0080] Example 10

[0081] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the pyrolysis temperature of step (4) is controlled at 1000℃, and the rest are the same as in Example 1.

[0082] Example 11

[0083] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the pyrolysis temperature of step (4) is controlled at 700°C, and the rest are the same as in Example 1.

[0084] Example 12

[0085] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the pyrolysis temperature of step (4) is controlled at 1700℃, and the rest are the same as in Example 1.

[0086] Example 13

[0087] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the pyrolysis time of step (4) is controlled to be 2 hours, and the rest are the same as in Example 1.

[0088] Example 14

[0089] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the heating rate of pyrolysis in step (4) is controlled at 5℃ / min, and the rest are the same as in Example 1.

[0090] Example 15

[0091] This embodiment provides a method for preparing activated carbon material. Compared with Example 1, the heating rate of pyrolysis in step (4) is controlled at 10℃ / min, and the rest are the same as in Example 1.

[0092] Comparative Example 1

[0093] This comparative example provides a method for preparing activated carbon material. Compared with Example 1, no metal salt is added in step (2), and the rest is the same as in Example 1.

[0094] Comparative Example 2

[0095] This comparative example provides a method for preparing activated carbon material. Compared with Example 1, the freezing in step (3) is not performed, and the rest is the same as in Example 1.

[0096] Performance Characterization

[0097] The pore size data of the activated carbon materials prepared in the examples and comparative examples were measured using the following methods:

[0098] The pore structure of activated carbon materials was obtained using an SSA-7300 pore size and specific surface area analyzer from Beijing Bio-Tech Electronics Co., Ltd. The pore size distribution and pore volume of the materials were obtained by testing the N2 adsorption-desorption isotherms, and the specific surface area was calculated using the BET method. The results are listed in Table 1.

[0099] Table 1

[0100]

[0101]

[0102] As shown in Table 1, the activated carbon material provided by this invention has a good specific surface area. The pore volume of mesopores with a pore size of 2-6 nm can account for 50-80% of the total pore volume, and the pore size and pore volume distribution is reasonable. It exhibits good adsorption effect on gasoline molecules, and the adsorption-desorption experiments on butane reflect the high adsorption capacity, strong adsorption ability, and good desorption effect of the activated carbon material, which is beneficial for the recycling of activated carbon. Furthermore, by using the optimized preparation parameters provided by this invention, the activated carbon material can achieve better performance in various aspects. Compared with Example 1, in Comparative Example 1, without the addition of metal salt, the butane retention data showed a significant decrease, and the desorption capacity of the material decreased. This indicates that introducing metal salt as a heat storage medium and rationally utilizing the heat effect of adsorption-desorption significantly improves the desorption effect of the activated carbon material. In Comparative Example 2, without freeze-drying, direct oven drying was used, resulting in changes in the pore structure of the material and a decrease in all performance data. Freeze-drying can increase the microporosity of the material, thereby improving the specific surface area and adsorption capacity, among other properties.

[0103] In summary, the preparation method provided by this invention uses chemical raw materials to replace traditional activated carbon raw materials such as biomass and charcoal, resulting in low cost and avoiding the disadvantage of uncontrollable basic properties of traditional activated carbon raw materials. Based on the adsorption characteristics of gasoline, the pore size distribution of the activated carbon material is precisely controlled, resulting in a large number of pores distributed in the 2-6 nm range, thus improving the adsorption-desorption effect of the activated carbon material. A heat storage medium is introduced to rationally utilize the adsorption-desorption heat effect, thereby increasing the adsorption capacity of the activated carbon material. Direct molding followed by carbonization and activation during the preparation of the activated carbon precursor solves the problem of pore blockage caused by the addition of binders in the traditional columnar activated carbon molding process, as well as the resulting reduction in adsorption-desorption performance. This method greatly preserves the pore structure of the activated carbon and improves the adsorption-desorption performance of the columnar carbon.

[0104] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing an activated carbon material in which the pore volume of mesopores with a pore size of 2-6 nm accounts for 50-80% of the total pore volume, characterized in that, The preparation method includes the following steps: (1) Mix and react polyhydroxyphenolic compounds, polyphospholipid compounds, a first catalyst, a polymeric surfactant, a metal salt, and a second catalyst to obtain the reaction product; (2) The reaction products obtained in step (1) are subjected to solid-liquid separation, molding, freezing and pyrolysis in sequence to obtain the activated carbon material; The polyhydroxyphenolic compound in step (1) includes any one or a combination of at least two of resorcinol, catechol, hydroquinone, pyrogallol or phlorogallol; The polyaldehyde compounds in step (1) include any one or a combination of at least two of glyoxal, malondialdehyde, succinaldehyde, glutaraldehyde, terephthalaldehyde, o-phthalaldehyde, isophthalaldehyde or pyromellitic aldehyde; Step (1) The first catalyst comprises any one or a combination of at least two of NH4OH, triethylamine, sodium bicarbonate or sodium carbonate; The metal salt in step (1) includes any one or a combination of at least two of FeCl3, ZnCl2, NiCl2, MgCl2 or CuCl2; The molar ratio of the metal salt to the polyhydroxyphenolic compound in step (1) is 1:(5-20); Step (1) The second catalyst comprises any one or a combination of at least two of hydrochloric acid, sulfuric acid, formic acid or acetic acid; The pyrolysis temperature in step (2) is 800-1600℃.

2. The preparation method according to claim 1, characterized in that, The molar ratio of the polyhydroxyphenolic compound to the polyaldehyde compound in step (1) is 1:(0.5-5).

3. The preparation method according to claim 1, characterized in that, Step (1) The molar ratio of the first catalyst to the polyhydroxyphenolic compound is 1:(100-500).

4. The preparation method according to claim 1, characterized in that, The polymeric surfactant in step (1) includes any one or a combination of at least two of F127, P123 or P407.

5. The preparation method according to claim 1, characterized in that, The molar ratio of the polymeric surfactant to the polyhydroxyphenolic compound in step (1) is 1:(100-300).

6. The preparation method according to claim 1, characterized in that, In step (1), the molar ratio of the second catalyst to the polyhydroxyphenolic compound is 1:(5-20).

7. The preparation method according to claim 1, characterized in that, The reaction temperature in step (1) is 60-120℃.

8. The preparation method according to claim 1, characterized in that, The reaction time in step (1) is 12-36 hours.

9. The preparation method according to claim 1, characterized in that, The freezing temperature in step (2) is from -22°C to -196°C.

10. The preparation method according to claim 1, characterized in that, The freezing time in step (2) is 2-48 hours.

11. The preparation method according to claim 1, characterized in that, The atmosphere for pyrolysis in step (2) includes N2 and / or CO2.

12. The preparation method according to claim 1, characterized in that, The heating rate of the pyrolysis in step (2) is 1-5℃ / min.

13. The preparation method according to claim 1, characterized in that, The pyrolysis time in step (2) is 1-2 hours.

14. An activated carbon material, characterized in that, The activated carbon material is prepared by the preparation method according to any one of claims 1-13; The activated carbon material is cylindrical carbon with a diameter of 2-3 mm or 3-5 mm.

15. An application of the activated carbon material as described in claim 14, characterized in that, The activated carbon material is used for gasoline vapor adsorption in automotive carbon canisters.

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