A processing method of carbon molecular sieve

Abstract

The present application relates to the field of carbon molecular sieve preparation, and specifically discloses a carbon molecular sieve processing method, comprising the following steps: S1, crushing flower mud to obtain a crushed powder; S2, weighing 30-40 parts of the crushed powder, 10-15 parts of resin oil, 15-25 parts of tar, and 25-35 parts of water according to a mass ratio, mixing and stirring uniformly to obtain a composite material; S3, extruding and carbonizing the composite material to obtain a semi-finished product, and adjusting the pore size of the semi-finished product to obtain a finished carbon molecular sieve, which has the advantages of high particle uniformity, high compressive strength, high nitrogen yield, and low air-nitrogen ratio.

Description

Technical Field

[0001] The present invention relates to the field of carbon molecular sieve preparation, and more specifically, to a method for processing carbon molecular sieve. Background Art

[0002] Carbon molecular sieve is a kind of columnar granular adsorbent with micropores on the surface and inside, which is made from coal, fruit shell, coconut shell or phenolic resin as the main raw materials through grinding, kneading, extrusion molding, carbonization and other processes, and then processed through a special pore treatment process.

[0003] Carbon molecular sieve has the ability to adsorb oxygen molecules in the air under normal temperature and pressure fluctuations, and can obtain nitrogen-rich gas. The ability to separate air depends on the different diffusion rates or different adsorption forces of various gases in the air in the micropores of the carbon molecular sieve.

[0004] The main element of carbon molecular sieve is carbon, and its appearance is a black columnar solid. It can be widely used in environmental protection, chemical industry, coal industry, electronics industry, food processing, hydrometallurgy, metal heat treatment, drug refining, petroleum industry, new energy, aerospace, transportation and storage.

[0005] Therefore, how to prepare a carbon molecular sieve with high particle uniformity, high compressive strength, high nitrogen yield and low air-nitrogen ratio is a problem to be solved. Summary of the Invention

[0006] In order to prepare a carbon molecular sieve with high particle uniformity, high compressive strength, high nitrogen yield and low air-nitrogen ratio, the present application provides a processing method of a carbon molecular sieve.

[0007] The present application provides a method for processing carbon molecular sieves, which adopts the following technical solution:

[0008] A method for processing carbon molecular sieves comprises the following steps:

[0009] S1. Grind the flower mud to obtain powder;

[0010] S2. Weigh 30-40 parts of crushed powder, 10-15 parts of resin oil, 15-25 parts of tar, and 25-35 parts of water according to the mass ratio, mix and stir evenly to obtain a composite material;

[0011] S3. The composite material is extruded and carbonized to obtain a semi-finished product, and the semi-finished product is pore-adjusted to obtain a finished carbon molecular sieve.

[0012] By adopting the above technical solution, after the flower mud is crushed, the particle size of the flower mud is reduced, and the coarse-grained impurities are reduced from clogging the pores of the carbon molecular sieve during subsequent carbonization. In addition, the specific surface area is increased after crushing, and the surface activity is enhanced. It is easier to form uniformly distributed micropores during the carbonization process, meeting the molecular sieve effect threshold required for nitrogen and oxygen separation, and facilitating the penetration and adhesion of resin oil, tar, and water. By forming a uniform composite material, structural defects caused by local uneven bonding during the carbonization process are avoided, thereby further ensuring the particle uniformity and compressive strength of the carbon molecular sieve.

[0013] The crushed flower mud is mixed with resin oil, tar and water. The bonding effect of resin oil and tar is used to bond the crushed powder to form a composite. During the high-temperature carbonization process, it can condense to form a three-dimensional cross-linked network, thereby increasing the binding force between particles and thus improving the compressive strength. In addition, with tar as the skeleton, amorphous carbon can be formed during the carbonization process to fill large pore defects. Combined with the resin oil, the carbon molecular sieve forms continuous pores while ensuring pore uniformity, further enhancing the mechanical strength of the carbon molecular sieve.

[0014] The volatile components in the resin oil overflow in an orderly manner during the carbonization stage, forming interconnected mesoporous channels. Combined with the micropores selectively covered by tar in the carbon layer, this reduces the probability of nitrogen being replaced by oxygen in the adsorption competition and increases the nitrogen yield.

[0015] The hydrophobic carbon surface produced by tar carbonization reduces the competitive adsorption of water molecules on the pores, increases the air-nitrogen ratio, and constrains the growth of the carbon layer through the π-π stacking effect during the co-carbonization process of resin oil and floral mud, thereby achieving a concentrated pore size distribution and further reducing the air-nitrogen ratio.

[0016] After the floral mud is extruded, carbonized and pore-adjusted, the carbon molecular sieve has the advantages of uniform particle distribution, high pore connectivity, low impurity content and good compressive strength.

[0017] Preferably, the specific steps of S1, the flower mud crushing process, are as follows:

[0018] The floral mud is preliminarily crushed to obtain floral mud microparticles, and a cellulase complex solution is added, and ultrasonic dispersion treatment is performed for 30-40 minutes. The temperature is raised to 80-100°C and treated for 6-10 minutes. Then, ethanol is added for washing 2-3 times, and the ethanol is filtered out. Then, a 3-5% hydrochloric acid solution is added, and after stirring evenly, the hydrochloric acid solution is filtered out, and the mixture is washed with water, dried, and ball-milled for a second time.

[0019] By adopting the above technical solution, after the floral mud particles are mixed with the cellulase complex liquid, the cellulase complex liquid can not only quickly penetrate and evenly contact the floral mud particles, but the cellulase can also selectively cut the glycosidic bonds, reduce the cross-linking resistance of the floral mud fibers, and promote the penetration of resin oil and tar into the fiber network to form a three-dimensional reinforced skeleton structure. After carbonization, the prepared carbon molecular sieve has high compressive strength.

[0020] Cellulase can effectively decompose the cellulose components in the floral mud and convert it into substances that are easier to carbonize, thereby improving the utilization and conversion efficiency of the carbon source. The decomposition effect of cellulase helps to form more tiny channels and pores inside the floral mud, providing favorable conditions for the escape of gas and the formation of pore structure during the carbonization process, so that the carbon molecular sieve has a higher porosity and adsorption effect, and can further increase the nitrogen yield and reduce the air-nitrogen ratio.

[0021] After cellulase treatment, the temperature is raised to inactivate the enzyme, and then ethanol washing is used to remove the inactivated cellulase as much as possible. The penetration effect of hydrochloric acid solution is then used to further dissolve metal impurities in the floral mud. Metallic iron, aluminum and other substances are dissolved and separated from the floral mud, reducing the impurity content in the floral mud and reducing the blockage of the microporous structure by impurities. Hydrochloric acid treatment can also remove cellulase and silicate impurities between particles, promote the generation of penetrating mesoporous channels, shorten the nitrogen diffusion path, increase nitrogen yield, and reduce the air-nitrogen ratio. At the same time, after the floral mud is treated with hydrochloric acid and cellulase, the stress concentration points inside the particles can be further eliminated, and the resin oil and tar can be more evenly penetrated during the carbonization process, thereby improving the compressive strength of the carbon molecular sieve.

[0022] Preferably, the carbon content of the floral mud in S1 is 75-80%, and the average particle size of the crushed powder is 1-2 μm.

[0023] By adopting the above technical solution, the carbon content of the flower mud and the average particle size of the crushed powder are limited, the compressive strength of the finished carbon molecular sieve is further improved, the nitrogen yield is increased, and the air-nitrogen ratio is reduced.

[0024] Preferably, the cellulase complex solution is prepared by the following method:

[0025] Cetearyl alcohol and cellulase are mixed and stirred evenly in a mass ratio of 1:2-4, then heated to 50-52°C and stirred for 1-3 minutes, and then cooled to room temperature to obtain a cellulase compound; the cellulase compound and water are mixed and stirred evenly in a mass ratio of 1:60-80 to obtain a cellulase compound liquid.

[0026] By adopting the above technical solution, cetearyl alcohol and cellulase are mixed, and the temperature is raised to the melting point of cetearyl alcohol, so that the surface of cetearyl alcohol is softened and hot-melted to produce viscosity, and cellulase is further loaded. The cellulase is evenly wrapped on the surface of cetearyl alcohol. Since cetearyl alcohol is insoluble in water, the cellulase in the prepared cellulase complex liquid can be evenly dispersed, and it is not easy to produce the problem of enzyme agglomeration and uneven contact with floral mud.

[0027] After the cellulase complex liquid is mixed with the floral mud particles, ultrasonic dispersion is used to further promote the contact between the cellulase complex and the floral mud particles. The treatment time is limited to ensure that the cellulase decomposes the cellulose in the floral mud particles. The temperature is then raised to 80-100°C, the cellulase is inactivated, and the cetearyl alcohol is completely melted and can carry the inactivated cellulase. Combined with the subsequent ethanol washing, the cetearyl alcohol is dissolved in ethanol. The better lubrication and fluidity of cetearyl alcohol can promote the cetearyl alcohol to carry the inactivated cellulase from the floral mud particles, thereby reducing the impurity content in the floral mud, improving the particle uniformity and nitrogen yield of the carbon molecular sieve, and reducing the air-nitrogen ratio.

[0028] Preferably, the resin oil comprises the following raw materials in parts by weight:

[0029] 86-92 parts of liquid phenolic resin, 4-6 parts of furfuryl alcohol resin, and 2-10 parts of polyethylene diamine solution.

[0030] By adopting the above technical solution, the amino groups in the polyethylenediamine solution and the hydroxyl groups in the furfuryl alcohol resin can form a hydrogen bond network, which improves the strength of the carbon molecular sieve after carbonization. In addition, after carbonization, the polyethylenediamine can generate a nitrogen-doped skeleton inside and on the surface of the carbon molecular sieve. The pyridine-N structure formed on the nitrogen-doped carbon surface has the advantage of specific adsorption for nitrogen molecules, which can increase the nitrogen yield. The 3-4 nm mesoporous transition layer produced by the thermal decomposition of the furfuryl alcohol resin can connect the micropores and macropores, thereby reducing the gas diffusion resistance, increasing the adsorption capacity of the carbon molecular sieve, and thus reducing the air-nitrogen ratio.

[0031] Liquid phenolic resin, polyethylene diamine solution and furfuryl alcohol resin are combined. Polyethylene diamine gradually releases ammonia after heating, which improves the three-dimensional through-microporous network of carbon molecular sieve. The high-temperature carbonization of benzene rings of phenolic resin induces directional arrangement of graphite microcrystals, improves the nitrogen yield of carbon molecular sieve and reduces the air-nitrogen ratio. The combination with furfuryl alcohol resin reduces the friction resistance between particles and further improves the uniformity of carbon molecular sieve particles. In addition, phenolic resin can form a dense protective film on the surface of carbon molecular sieve, inhibiting micropore collapse caused by airflow scouring and ensuring the strength of carbon molecular sieve.

[0032] Preferably, in S2, after mixing the crushed material with water, adding polyethylene diamine solution, ultrasonically dispersing them uniformly, adding liquid phenolic resin and furfuryl alcohol resin and mixing and stirring them uniformly, and finally adding tar, mixing and stirring them uniformly to obtain a composite material.

[0033] By adopting the above technical solution, first, the crushed powder is mixed with water, and then a polyethylenediamine solution is added. The water-soluble penetration effect of the polyethylenediamine is utilized in combination with ultrasonic dispersion to promote uniform contact between the polyethylenediamine and the crushed powder. During the carbonization and heating process, the polyethylenediamine forms a nitrogen-doped structure on the surface of the carbon matrix, and the gradual release of ammonia further promotes the generation of pores in the composite material. The lower viscosity of the furfuryl alcohol resin and the hydrogen bond connection between the hydroxyl group and the polar group on the surface of the crushed powder are combined to promote uniform penetration of the liquid phenolic resin, thereby improving the structural stability of the composite material. After carbonization, the compressive strength and pore uniformity of the carbon molecular sieve are guaranteed. Oxygen-rich functional groups are formed on the surface of the carbonized product of the furfuryl alcohol resin, which preferentially adsorbs oxygen molecules, ensures nitrogen purity, and improves nitrogen yield. In addition, the synergistic carbonization of the furfuryl alcohol resin and tar can form a mesoporous-microporous gradient structure, thereby reducing the air-nitrogen ratio.

[0034] Preferably, the tar is composed of tar liquid and polyethylene glycol solution in a mass ratio of 1:0.05-0.1.

[0035] By adopting the above technical solution, the polyethylene glycol solution can adjust the viscosity of the tar liquid, reduce the flow resistance, and improve the contact uniformity, thereby improving the uniformity of the carbon molecular sieve particles. In addition, the thermal decomposition of polyethylene glycol can form a mesoporous transition layer, reduce the gas diffusion resistance, and increase the nitrogen yield. The tar liquid mainly controls the micropores to adsorb oxygen, and the mesoporous network of polyethylene glycol accelerates nitrogen desorption, thereby reducing the air-nitrogen ratio. At the same time, the tar carbon skeleton cooperates with the nanocarbon generated by the thermal decomposition of polyethylene glycol to form a complementary reinforcement structure in the carbon molecular sieve, thereby improving the compressive strength of the carbon molecular sieve.

[0036] Preferably, the extruded strip has a diameter of 1.1-1.5 mm and a length of 1.5-3 mm.

[0037] By adopting the above technical solution, the short strip structure reduces the diffusion distance of gas molecules in the pores, and combined with the extruded strip diameter, more uniform micropores can be formed during the carbonization shrinkage process, thereby increasing the nitrogen yield, reducing the air-nitrogen ratio, and improving the compressive strength.

[0038] Preferably, the carbonization steps are as follows: first, carbonize at 300-400°C for 0.5-1h, then heat to 500-650°C for 1-2h, and finally heat to 700-850°C for 2-3h.

[0039] By adopting the above technical solution, preliminary carbonization is first carried out at 300-400℃ to ensure the uniformity and penetration effect of gas flow pores, and then carbonization is carried out at 500-650℃ to promote the generation of pyrrole-N during the nitrogen doping process. The subsequent carbonization at 700-850℃ further improves the stability of nitrogen doping and the uniformity of carbonization, so that the finished carbon molecular sieve has the advantages of high mechanical strength, high particle uniformity, high nitrogen yield and low air-nitrogen ratio.

[0040] Preferably, the hole adjustment steps are as follows:

[0041] The semi-finished product is added with 3-5% benzene and 3-5% water by weight and treated at 700-800°C for 2-3 hours.

[0042] By adopting the above technical solution, benzene volatilizes under high temperature conditions, further increasing the gas overflow channels, ensuring the nitrogen yield, and reducing the air-nitrogen ratio; and the polycyclic aromatic hydrocarbons (such as graphite crystals) generated by the high-temperature cracking of benzene are embedded in the defective areas of the carbon skeleton through π-π stacking, thereby improving the density uniformity of the carbon molecular sieve, thereby improving the compressive strength and particle uniformity of the carbon molecular sieve.

[0043] In summary, this application has the following beneficial effects:

[0044] 1. The crushed flower mud is mixed with resin oil, tar and water. After carbonization, the carbon molecular sieve has the advantages of high particle uniformity, high compressive strength, high nitrogen yield and low air-nitrogen ratio.

[0045] 2. Phenolic resin can generate glassy carbon phase during the carbonization process, which forms a complementary reinforcement with the carbon skeleton of phenolic resin by the nitrogen-doped structure formed by carbonization of polyethylenediamine and the glassy carbon phase formed by carbonization of furfuryl alcohol resin. The nano-carbon whiskers cross-braced by pyrolysis of furfuryl alcohol resin penetrate into the pores, thereby further improving the compressive strength of the finished carbon molecular sieve.

[0046] 3. The polyethylene diamine solution, polyethylene glycol solution and furfuryl alcohol resin are combined to further increase the internal interconnected porosity of the carbon molecular sieve, increase the nitrogen yield of the carbon molecular sieve and reduce the air-nitrogen ratio. DETAILED DESCRIPTION

[0047] The present application is further described in detail below with reference to the embodiments.

[0048] Preparation example of cellulase complex solution

[0049] Among the following raw materials, cellulase was purchased from Shandong Pingju Biotechnology Co., Ltd.; other raw materials were commercially available.

[0050] Preparation Example 1: Cellulase complex solution was prepared by the following method:

[0051] Cetearyl alcohol and cellulase are mixed and stirred evenly in a mass ratio of 1:3, the average particle size of the cellulase is 80 μm, and then the temperature is raised to 51° C. for treatment for 2 minutes, and then cooled to room temperature of 25° C. to obtain a cellulase composite material; the cellulase composite material and water are mixed and stirred evenly in a mass ratio of 1:70 to obtain a cellulase composite liquid.

[0052] Preparation Example 2: This preparation example differs from Preparation Example 1 in that:

[0053] Cetearyl alcohol and cellulase are mixed and stirred evenly in a mass ratio of 1:2, then heated to 50°C for 3 minutes, and then cooled to room temperature of 25°C to obtain a cellulase compound; the cellulase compound and water are mixed and stirred evenly in a mass ratio of 1:60 to obtain a cellulase compound liquid.

[0054] Preparation Example 3: This preparation example differs from Preparation Example 1 in that:

[0055] Cetearyl alcohol and cellulase were mixed and stirred evenly in a mass ratio of 1:4, then heated to 52°C for 1 minute, and then cooled to room temperature of 25°C to obtain a cellulase compound; the cellulase compound and water were mixed and stirred evenly in a mass ratio of 1:80 to obtain a cellulase compound liquid.

[0056] Tar Preparation Example

[0057] The following raw materials are all commercially available.

[0058] Preparation Example 4: Tar was prepared by the following method:

[0059] 1 kg of tar liquid was weighed and mixed with 0.08 kg of polyethylene glycol solution, wherein the polyethylene glycol solution was a 2% by mass polyethylene glycol ethanol solution, the ethanol mass fraction was 95%, and the polyethylene glycol was polyethylene glycol 800, to obtain tar.

[0060] Preparation Example 5: This preparation example differs from Preparation Example 4 in that:

[0061] Weigh 1 kg of tar liquid and 0.05 kg of polyethylene glycol solution, mix and stir evenly to obtain tar.

[0062] Preparation Example 6: This preparation example differs from Preparation Example 4 in that:

[0063] Weigh 1 kg of tar liquid and 0.1 kg of polyethylene glycol solution, mix and stir evenly to obtain tar. Example

[0064] The following raw materials are all commercially available.

[0065] Example 1: A method for processing carbon molecular sieves:

[0066] S1. The floral mud is preliminarily crushed to obtain floral mud microparticles, the carbon content of the floral mud is 78-80%, and the average particle size of the floral mud microparticles is 40 μm. The cellulase complex solution prepared in Preparation Example 1 is added, and the mass ratio of the floral mud microparticles to the cellulase complex solution is 1:10. The mixture is ultrasonically dispersed at 20 kHz for 35 min, heated to 95° C. for 8 min, and then washed three times with 75% ethanol by mass. The floral mud microparticles are filtered out, and the ethanol is filtered out to obtain a pretreated material; a 4% hydrochloric acid solution is added to the pretreated material, and the solvent is water. The mixture is stirred at a speed of 500 r / min for 20 min. After uniform mixing, the hydrochloric acid solution is filtered out, the mixture is washed three times with water, and air-dried. Then, the mixture is subjected to a secondary ball milling to obtain a crushed powder with an average particle size of 1.5 μm.

[0067] S2, 38kg crushed material is mixed with 30kg water, under the rotating speed of 1000r / min, stir, add 0.72kg polyethylenediamine solution, polyethylenediamine solution is the polyethylenediamine ethanol solution of massfraction 1%, ethanol massfraction is 95%, under 20kHz condition, ultrasonic dispersion 10min, after mixing, add 10.8kg liquid phenolic resin and 0.48kg furfuryl alcohol resin mixing, stir, finally add the tar prepared by 20kg preparation example 4, mixing and stirring, obtain composite material; Resin oil comprises liquid phenolic resin, polyethylenediamine solution and furfuryl alcohol resin;

[0068] S3. The composite material is extruded into strips with an average diameter of 1.2 mm and an average length of 2 mm, and then carbonized. First, carbonization is carried out at 350°C for 1 hour, then carbonization is carried out at 600°C for 1.5 hours, and finally carbonization is carried out at 800°C for 2.5 hours. A semi-finished product is obtained after carbonization. 4% by weight of benzene and 4% by weight of water are added to the semi-finished product, and then the product is treated at 750°C for 2.5 hours to complete the pore adjustment and obtain a finished carbon molecular sieve.

[0069] Example 2: This example differs from Example 1 in that:

[0070] S1. The floral mud is preliminarily crushed to obtain floral mud microparticles, the carbon content of the floral mud is 75-78%, and the average particle size of the floral mud microparticles is 40 μm. The cellulase complex solution prepared in Preparation Example 2 is added, and the mass ratio of the floral mud microparticles to the cellulase complex solution is 1:10. The mixture is ultrasonically dispersed at 20 kHz for 30 min, heated to 80° C. for 10 min, and then washed twice with 75% ethanol by mass. The floral mud microparticles are filtered out, and the ethanol is filtered out to obtain a pretreated material; a 3% hydrochloric acid solution is added to the pretreated material, and the solvent is water. The mixture is stirred at a speed of 500 r / min for 20 min. After uniform mixing, the hydrochloric acid solution is filtered out, the mixture is washed with water three times, air-dried, and then subjected to secondary ball milling to obtain a crushed powder with an average particle size of 2 μm.

[0071] S2, 40kg crushed material is mixed with 35kg water, under the rotating speed of 1000r / min, stir, add 0.2kg polyethylenediamine solution, polyethylenediamine solution is the polyethylenediamine ethanol solution of mass fraction 1%, ethanol mass fraction is 95%, under 20kHz condition, ultrasonic dispersion 10min, after mixing, add 9.2kg liquid phenolic resin and 0.6kg furfuryl alcohol resin mixing, stir, finally add the tar prepared by 15kg preparation example 5, mixing and stirring, obtain composite material; Resin oil comprises liquid phenolic resin, polyethylenediamine solution and furfuryl alcohol resin;

[0072] S3. The composite material is extruded into strips with an average diameter of 1.5 mm and an average length of 3 mm, and then carbonized. First, the strips are carbonized at 300°C for 1 hour, then heated to 500°C for 2 hours, and finally heated to 700°C for 3 hours to obtain a semi-finished product. 3% by weight of benzene and 3% by weight of water are added to the semi-finished product, and then treated at 700°C for 3 hours to complete the pore adjustment and obtain a finished carbon molecular sieve.

[0073] Example 3: This example differs from Example 1 in that:

[0074] S1. The floral mud is preliminarily crushed to obtain floral mud microparticles having a carbon content of 78-80% and an average particle size of 40 μm. The cellulase complex prepared in Preparation Example 3 is added, and the mass ratio of the floral mud microparticles to the cellulase complex is 1:10. The mixture is ultrasonically dispersed at 20 kHz for 40 min, heated to 100° C. for 6 min, and then washed three times with 75% ethanol by mass. The floral mud microparticles and the ethanol are filtered out to obtain a pretreated material. A 5% hydrochloric acid solution is added to the pretreated material, and the solvent is water. The mixture is stirred at a speed of 500 r / min for 20 min. After uniform mixing, the hydrochloric acid solution is filtered out, the mixture is washed three times with water, and air-dried. The mixture is then subjected to a secondary ball milling to obtain a crushed powder having an average particle size of 1 μm.

[0075] S2, 35kg crushed material is mixed with 25kg water, under the rotating speed of 1000r / min, stir, add 1.5kg polyethylenediamine solution, polyethylenediamine solution is the polyethylenediamine ethanol solution of mass fraction 1%, ethanol mass fraction is 95%, under 20kHz condition, ultrasonic dispersion 10min, after mixing, add 12.9kg liquid phenolic resin and 0.6kg furfuryl alcohol resin mixing, stir, finally add the tar prepared by 25kg preparation example 6, mixing and stirring, obtain composite material; Resin oil comprises liquid phenolic resin, polyethylenediamine solution and furfuryl alcohol resin;

[0076] S3. The composite material is extruded into strips with an average diameter of 1.1 mm and an average length of 1.5 mm, and then carbonized. First, carbonization is carried out at 400°C for 0.5 h, then carbonization is carried out at 650°C for 1 h, and finally carbonization is carried out at 850°C for 3 h. A semi-finished product is obtained after carbonization. 5% by weight of benzene and 5% by weight of water are added to the semi-finished product, and then the product is treated at 800°C for 2 h to complete the pore adjustment and obtain a finished carbon molecular sieve.

[0077] Example 4: This example differs from Example 1 in that:

[0078] The floral mud pulverization process is direct pulverization; that is, no cellulase complex solution is added during the process, and no hydrochloric acid solution treatment is performed.

[0079] Example 5: This example differs from Example 1 in that:

[0080] No cetearyl alcohol was added to the cellulase complex solution during the floral mud crushing process.

[0081] Example 6: This example differs from Example 1 in that:

[0082] The resin oil is a liquid phenolic resin, that is, no furfuryl alcohol resin and polyethylene diamine solution are added.

[0083] Example 7: This example differs from Example 1 in that:

[0084] No polyethylene glycol solution was added to the tar.

[0085] Example 8: This example differs from Example 1 in that:

[0086] The carbonization temperature is 800℃ and the carbonization time is 5h.

[0087] Performance testing

[0088] 1. Nitrogen yield detection

[0089] Carbon molecular sieves were prepared using the methods of Examples 1-8, respectively, with reference to HG / T4364-2020, and the nitrogen yield was recorded under a standard pressure of 0.8 MPa.

[0090] 2. Air-nitrogen ratio detection

[0091] The methods of Examples 1-8 were used to prepare carbon molecular sieves, respectively, and the air-nitrogen ratio was calculated.

[0092] 3. Uniformity detection

[0093] The carbon molecular sieves were prepared by the methods of Examples 1-8 respectively, and sieving was performed to record the proportion of carbon molecular sieves with a particle diameter of 1.1-1.2 mm. The total amount of carbon molecular sieve particles was 10,000, and the proportion data was recorded. The higher the proportion, the higher the particle uniformity.

[0094] 4. Compressive strength test

[0095] The carbon molecular sieves were prepared using the methods of Examples 1-8, respectively, and the compressive strength was recorded with reference to HG / T4364-2020.

[0096] Table 1 Performance test table

[0097]

[0098] In combination with Examples 1-3 and Table 1, it can be seen that the penetration and adhesion effect of resin oil and tar is utilized to avoid structural defects caused by local uneven bonding during the carbonization process, thereby further ensuring the particle uniformity of the carbon molecular sieve, and can be polycondensed to form a three-dimensional cross-linked network during the high-temperature carbonization process, thereby increasing the binding force between the particles and thus improving the compressive strength. Moreover, the interconnected microporous structure formed by the carbonization of resin oil and tar further increases the nitrogen yield of the carbon molecular sieve and reduces the air-nitrogen ratio.

[0099] Combining Example 1 and Examples 4-8 and Table 1, it can be seen that the floral mud crushing process in Example 4 is direct crushing; that is, no cellulase complex liquid is added during the process, and it is not treated with hydrochloric acid solution. Compared with Example 1, the carbon molecular sieve prepared in Example 4 has a lower nitrogen yield than Example 1, a higher air-nitrogen ratio than Example 1, a lower particle uniformity than Example 1, and a lower compressive strength than Example 1; this shows that the addition of cellulase complex liquid and hydrochloric acid can reduce the cross-linking resistance of floral mud fibers, ensure particle uniformity, remove impurities, promote the penetration of resin oil and tar into the fiber network, and improve the compressive strength of the carbon molecular sieve; the fiber bundle enzyme complex liquid decomposes the substances in the floral mud more easily and carbonizes them, so that the carbon molecular sieve has a higher porosity and adsorption effect, and further improves the nitrogen yield and reduces the air-nitrogen ratio.

[0100] In Example 5, cetearyl alcohol was not added to the cellulase complex solution during the floral mud crushing process. Compared with Example 1, the carbon molecular sieve prepared in Example 5 had a lower nitrogen yield than that in Example 1, a higher air-nitrogen ratio than that in Example 1, a lower particle uniformity than that in Example 1, and a lower compressive strength than that in Example 1. This indicates that cetearyl alcohol facilitates uniform contact between cellulase and floral mud, and combined with ethanol washing, cetearyl alcohol has better lubrication and fluidity, which facilitates the separation of cellulase from the floral mud, thereby ensuring the porosity and particle uniformity of the carbon molecular sieve, and can also ensure the penetration of resin oil, ensuring that the carbon molecular sieve has high compressive strength.

[0101] The resin oil in Example 6 is liquid phenolic resin, that is, furfuryl alcohol resin and polyethylenediamine solution are not added. Compared with Example 1, the carbon molecular sieve prepared in Example 6 has a lower nitrogen yield than that in Example 1, a higher empty nitrogen ratio than that in Example 1, a lower particle uniformity than that in Example 1, and a lower compressive strength than that in Example 1; this indicates that the furfuryl alcohol resin and the polyethylenediamine solution are matched, and the fluidity of the furfuryl alcohol resin facilitates the polyethylenediamine solution and the liquid phenolic resin to enter the internal pores of the floral mud, and cooperates with the nitrogen doping effect of the polyethylenediamine solution to further improve the nitrogen yield, reduce the empty nitrogen ratio, and improve the compressive strength, thereby ensuring particle uniformity.

[0102] No polyethylene glycol solution was added to the tar in Example 7. Compared with Example 1, the carbon molecular sieve prepared in Example 7 had a lower nitrogen yield than that in Example 1, a higher air-nitrogen ratio than that in Example 1, a lower particle uniformity than that in Example 1, and a lower compressive strength than that in Example 1. This indicates that the polyethylene glycol solution has good fluidity. During the carbonization process, the gas overflows evenly, ensuring the porosity of the carbon molecular sieve, so that the carbon molecular sieve has the advantages of high nitrogen yield, low air-nitrogen ratio, and high particle uniformity. In addition, the polyethylene glycol solution promotes the tar to enter the interior of the floral mud, thereby improving the compressive strength of the finished carbon molecular sieve. At the same time, the dispersion effect of polyethylene glycol ensures the particle uniformity.

[0103] The carbonization temperature of Example 8 is 800°C and the carbonization is carried out for 5 hours. Compared with Example 1, the nitrogen yield of the carbon molecular sieve prepared in Example 8 is lower than that in Example 1, the air-nitrogen ratio is higher than that in Example 1, the particle uniformity is lower than that in Example 1, and the compressive strength is lower than that in Example 1; this indicates that the segmented carbonization can ensure the production of nitrogen-doped structure pyridine-N, while ensuring the nitrogen doping effect, and the temperature segmented carbonization can avoid cracking or pore collapse caused by the violent release of moisture and volatiles, thereby ensuring the uniformity of the pore size of the carbon molecular sieve, and making the carbon molecular sieve have higher compressive strength, nitrogen yield, particle uniformity, and reduce the air-nitrogen ratio.

[0104] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A method for processing a carbon molecular sieve, characterized in that: The steps include: S1. The floral mud is preliminarily crushed to obtain floral mud microparticles, a cellulase complex solution is added, and ultrasonic dispersion is performed for 30-40 minutes. The mixture is heated to 80-100°C and treated for 6-10 minutes. The mixture is then washed with ethanol 2-3 times, the ethanol is filtered out, and a 3-5% hydrochloric acid solution is added. After stirring, the hydrochloric acid solution is filtered out, and the mixture is washed with water, dried, and subjected to a second ball milling to obtain a powder. S2. Weigh 30-40 parts of crushed powder, 10-15 parts of resin oil, 15-25 parts of tar, and 25-35 parts of water according to the mass ratio, mix and stir evenly to obtain a composite material; S3, the composite material is extruded and carbonized to obtain a semi-finished product, and the semi-finished product is pore-adjusted to obtain a finished carbon molecular sieve; The cellulase complex solution was prepared by the following method: Cetearyl alcohol and cellulase are mixed and stirred evenly in a mass ratio of 1:2-4, then heated to 50-52°C and stirred for 1-3 minutes, and then cooled to room temperature to obtain a cellulase compound; the cellulase compound and water are mixed and stirred evenly in a mass ratio of 1:60-80 to obtain a cellulase compound liquid.

2. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The carbon content of the floral mud in S1 is 75-80%, and the average particle size of the crushed powder is 1-2 μm.

3. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The resin oil comprises the following raw materials in parts by weight: 86-92 parts of liquid phenolic resin, 4-6 parts of furfuryl alcohol resin and 2-10 parts of polyethylene diamine solution.

4. The method for processing a carbon molecular sieve according to claim 3, characterized in that: S2, after mixing the crushed material with water, adding polyethylene diamine solution, ultrasonically dispersing it evenly, adding liquid phenolic resin and furfuryl alcohol resin, mixing and stirring evenly, and finally adding tar, mixing and stirring evenly to obtain a composite material.

5. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The tar consists of tar liquid and polyethylene glycol solution in a mass ratio of 1:0.05-0.

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6. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The diameter of the extruded strip is 1.1-1.5 mm, and the length is 1.5-3 mm.

7. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The specific steps of carbonization are as follows: first, carbonize at 300-400° C. for 0.5-1 h, then heat to 500-650° C. for 1-2 h, and finally heat to 700-850° C. for 2-3 h.

8. The method for processing a carbon molecular sieve according to claim 1, characterized in that: The specific steps of adjusting the hole are as follows: The semi-finished product is added with 3-5% benzene and 3-5% water by weight and treated at 700-800°C for 2-3 hours.

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