Carbon molecular sieve and preparation method thereof
By using biochar as a carbon source and combining urea crosslinking, carbonization, and activation processes, a high-efficiency, low-cost carbon molecular sieve was prepared, solving the problems of unstable product quality and high cost caused by resin raw materials, and achieving price advantages and performance improvements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-16
- Publication Date
- 2026-03-27
AI Technical Summary
In the current production of carbon molecular sieves, the use of resin-based raw materials leads to unstable product quality and high costs, due to the high price of synthetic resins.
Using bio-coke as a carbon source, carbon molecular sieves are prepared by removing inorganic matter, cross-linking with urea, grinding into granules, mixing with bio-pyrolysis oil and water, extruding, carbonizing and activating, and finally depositing benzene in a rotary kiln.
This reduces raw material costs, enhances the price advantage of the product, and the prepared carbon molecular sieve has good compressive strength and gas separation performance.
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Figure CN121735252A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of carbon molecular sieve, and particularly relates to a carbon molecular sieve and a preparation method. BACKGROUND
[0002] At present, in the preparation process of carbon molecular sieve, resin raw materials are generally used by carbon molecular sieve manufacturers because the resin raw materials have regular molecular structures and contain a certain amount of oxygen-containing groups. However, the quality of the carbon molecular sieve produced by the synthetic resin is affected to different degrees due to the different addition of curing agents, foaming agents and flame retardants, and the cost of the carbon molecular sieve produced by the synthetic resin is high.
[0003] How to solve the above technical problems has become a technical problem to be solved in the industry. SUMMARY
[0004] In order to solve the defects of the prior art, the purpose of the present application is to provide a carbon molecular sieve and a preparation method, which uses biochar as a carbon source, has a low raw material price and reduces the production cost.
[0005] To achieve the above purpose, the present application provides a preparation method of a carbon molecular sieve, comprising: removing inorganic substances in biochar to less than 100 ppm; mixing the biochar and urea, and then placing them in a reaction furnace to react and crosslink into a macromolecular structure; polishing the macromolecular structure into biochar particles; mixing the biochar particles with bio-oil and water, and then extruding and forming to obtain carbon molecular sieve extruded strips; carbonizing the carbon molecular sieve extruded strips in a rotary furnace; after the carbonization is completed, water vapor is introduced into the rotary furnace for activation; after the activation is completed, benzene is introduced into the rotary furnace for deposition to obtain the carbon molecular sieve.
[0006] Preferably, the step of removing inorganic substances in biochar to less than 100 ppm is obtained by soaking the biochar into a hydrochloric acid solution after the biochar is made into biochar particles and dried; The particle size of the biochar particles is 1 mm to 5 mm. The content of hydrochloric acid in the hydrochloric acid solution is 0.1 mol / L.
[0007] Preferably, the step of mixing the biochar and urea, and then placing them in a reaction furnace to react and crosslink into a macromolecular structure comprises: The mass ratio of the biochar to the urea is 1:0.05 to 0.15.
[0008] Preferably, the step of mixing the biochar and urea, and then placing them in a reaction furnace to react and crosslink into a macromolecular structure further comprises: The working temperature of the reaction furnace is 200-400 DEG C, and the reaction time is 2-6 hours.
[0009] Preferably, in the step of polishing the macromolecular structure into biochar particles, 50% of the biochar particles have a particle size of 3-12 microns.
[0010] Preferably, the step of mixing the biochar particles with bio-oil and water and extruding into a strip to obtain the carbon molecular sieve extruded strip comprises: The mass ratio of biochar, bio-oil and water is 1:0.1-0.4:0.3-0.6.
[0011] Preferably, the carbon molecular sieve extruded strip has a particle size of 1.2-2.0 mm and a length of 1-7 mm.
[0012] Preferably, the step of carbonizing the carbon molecular sieve extruded strip in a rotary furnace comprises: The rotary furnace is heated to 700-850 DEG C at a heating rate of 2-10 DEG C / min, and then kept at the temperature when the heating stops for 0.5-2.5 hours.
[0013] Preferably, the step of activating the carbon molecular sieve extruded strip by passing water vapor into the rotary furnace comprises: The flow rate of water vapor is 30-60 ml / min, and the activation time is 0.5-3 hours.
[0014] Preferably, the step of depositing benzene into the rotary furnace to obtain the carbon molecular sieve comprises: The flow rate of benzene is 5-40 ml / min, and the deposition time is 1-10 hours.
[0015] To achieve the above object, the carbon molecular sieve is prepared by the above preparation method.
[0016] The above technical solution uses biochar as the carbon source, the raw material is easy to obtain and cheap, thereby reducing the raw material cost and improving the price advantage of the product.
[0017] Other features and advantages of the present application will be described in the following description, and some will become apparent from the description, or will be learned from practice of the present application. BRIEF DESCRIPTION OF DRAWINGS
[0018] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, and together with the embodiments of the present application, serve to explain the present application, and do not constitute a limitation on the present application. In the drawings: Figure 1A flow chart of a preparation method of the carbon molecular sieve according to the embodiment of the present application. DETAILED DESCRIPTION
[0019] The preferred embodiments of the present application will be described herein below with reference to the drawings; it should be understood that the preferred embodiments described herein are merely intended to describe and explain the present application, and should not be used to limit the present application.
[0020] The embodiments of the present application will be described in more detail herein below with reference to the drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms, and should not be interpreted as being limited to the embodiments set forth herein, but rather, these embodiments are provided to make the present application more thorough and complete. It should be understood that the drawings and embodiments of the present application are merely intended for exemplary purposes, and should not be used to limit the scope of protection of the present application.
[0021] The term “comprising” and variations thereof as used herein are open-ended, that is “including but not limited to”. The term “based on” is “based, at least in part, on”. The term “one embodiment” means “at least one embodiment”; the term “another embodiment” means “at least one additional embodiment”; the term “some embodiments” means “at least some embodiments”. Related definitions will be given in the description below.
[0022] It should be noted that the terms “first”, “second”, etc. mentioned in the present application are merely used to distinguish different devices, components or parts, and are not used to limit the order or interdependence of the functions performed by these devices, components or parts.
[0023] It should be noted that the modification of “one” or “multiple” mentioned in the present application is illustrative but not limiting, and those skilled in the art should understand that, unless otherwise explicitly indicated in the context, it should be understood as “one or more”. “Multiple” should be understood as two or more.
[0024] The preparation method of the carbon molecular sieve of the present application comprises: removing inorganic substances in the biochar to less than 100 ppm; mixing the biochar and urea and then placing them in a reaction furnace to react and crosslink into a macromolecular structure; polishing the macromolecular structure into biochar particles; mixing the biochar particles with bio-oil and water and extruding into strips to obtain carbon molecular sieve extruded strips; carbonizing the carbon molecular sieve extruded strips in a rotary furnace; after the carbonization is completed, water vapor is introduced into the rotary furnace for activation; after the activation is completed, benzene is introduced into the rotary furnace for deposition to obtain the carbon molecular sieve.
[0025] For the purpose, technical solutions and advantages of the present application to be clearer, the embodiments of the present application will be described in further detail below with reference to the drawings.
[0026] Example 1 Figure 1 For the process flow diagram of the preparation method of the carbon molecular sieve according to the embodiments of the present application, as shown in Figure 1 the preparation method of the carbon molecular sieve according to the embodiments of the present application is used to prepare the carbon molecular sieve.
[0027] First, in step 101, the inorganic matter in the biochar is removed to less than 100 ppm.
[0028] In an exemplary embodiment, the biochar is used as the carbon source in the embodiments of the present application, and a large amount of bio-pyrolysis oil is produced in the forestry chemical industry and the agricultural chemical industry, and the residue after distillation of the pyrolysis oil is the biochar.
[0029] In an exemplary embodiment, the biochar is rich in carbonaceous substances, incompletely pyrolyzed organic matter and a small amount of ash, and the raw material is easy to obtain, the price is cheap, the carbon content is high, and the volatile matter is large, which is an excellent raw material for producing carbon molecular sieve.
[0030] In an exemplary embodiment, the carbonaceous substances are semi-cellulose, cellulose and lignin incomplete pyrolysis products or condensates in biomass, the incompletely pyrolyzed organic matter includes lignin fragments, polycyclic aromatic hydrocarbons or other macromolecular carbon hydroxide compounds, and the small amount of ash is inorganic components.
[0031] In an exemplary embodiment, the ash in the biochar must be removed by acid washing, for example, the biochar is coarsely crushed into biochar particles, and the diameter size of the biochar particles is 1 mm to 5 mm.
[0032] In an exemplary embodiment, the biochar particles are then placed in an acid solution for acid washing, which can not only remove the ash in the biochar, but also dissolve the inorganic components in the biochar in the acid solution.
[0033] In an exemplary embodiment, the acid solution is a hydrochloric acid solution, and the content of hydrochloric acid in the hydrochloric acid solution is 0.1 mol / L.
[0034] In an exemplary embodiment, the biochar particles are subjected to acid washing until the inorganic matter content is less than 100 ppm.
[0035] In an exemplary embodiment, the biochar particles are soaked in the hydrochloric acid solution for not less than 12 hours, so that the inorganic components in the biochar are dissolved in the hydrochloric acid solution, most of the ash in the biochar is removed, and after the inorganic matter content in the biochar is less than 100 ppm, the biochar particles are subjected to centrifugal drying treatment.
[0036] Step 102, after mixing the biochar and urea, place them in a reaction furnace to react and cross-link into a macromolecular structure.
[0037] In an exemplary embodiment, the biochar particles after acid washing and drying are subjected to viscosity reduction modification, for example, the biochar particles after acid washing and drying are blended with urea, wherein the mass ratio of biochar to urea is 1:0.05 to 0.15.
[0038] In an exemplary embodiment, after the biochar particles are blended with urea, they are placed in a reaction furnace to react, the working temperature of the reaction furnace is 200°C to 400°C, the reaction time is 2 hours to 6 hours, the reaction cross-links into a macromolecular structure, thereby solidifying into a solid substance, reducing the bonding performance, and simultaneously performing nitrogen-doped modification.
[0039] Step 103, grind the macromolecular structure into biochar particles.
[0040] In an exemplary embodiment, the biochar after viscosity reduction modification is ground into biochar particles, for example, the biochar is put into a ball mill for ball milling for 16 hours to 24 hours, and the particle size of 50% of the particles is 3μm to 12μm.
[0041] Step 104, mix the biochar particles with bio-pyrolysis oil and water, and extrude into a carbon molecular sieve extruded material.
[0042] In an exemplary embodiment, the biochar particles are mixed with bio-pyrolysis oil as a binder and water as an auxiliary agent, and after uniform mixing, the mixture is extruded into a carbon molecular sieve extruded material by an extruder.
[0043] In an exemplary embodiment, the mass ratio of biochar, bio-pyrolysis oil, and water is 1:0.1 to 0.4:0.3 to 0.6.
[0044] In an exemplary embodiment, the particle size of the carbon molecular sieve extruded material is 1.2mm to 2.0mm, and the length size is 1mm to 7mm.
[0045] Step 105, carbonize the carbon molecular sieve extruded material in a rotary furnace.
[0046] In an exemplary embodiment, the carbon molecular sieve extruded material is then carbonized and activated, the carbon molecular sieve extruded material is put into a rotary furnace, the rotary furnace is raised to 700°C to 850°C at a temperature rising rate of 2°C / min to 10°C / min, and then kept at the temperature when the temperature rising stops for 0.5 hours to 2.5 hours; for example, the rotary furnace is raised to 700°C at a temperature rising rate of 5°C / min, and then kept at 700°C for 1 hour.
[0047] Step 106, after carbonization is completed, water vapor is introduced into the rotary furnace for activation.
[0048] In an exemplary embodiment, after the holding time is over, i.e. after carbonization is completed, water vapor is introduced into the rotary furnace for activation.
[0049] In an exemplary embodiment, the flow rate of water vapor is 30ml / min to 60ml / min, the activation time is 0.5h to 3h, and the water vapor input into the rotary furnace is stopped when the activation time is over.
[0050] Step 107, after activation is completed, benzene is introduced into the rotary furnace for deposition to obtain carbon molecular sieve.
[0051] In an exemplary embodiment, after both carbonization and activation are completed, benzene is introduced into the rotary furnace for deposition to obtain carbon molecular sieve.
[0052] In an exemplary embodiment, the flow rate of benzene is 5ml / min to 40ml / min, and the deposition time is 1h to 10h.
[0053] In an exemplary embodiment, the benzene enters the rotary furnace in liquid form and is converted into gaseous form after being heated.
[0054] In an exemplary embodiment, the carbon molecular sieve prepared by the above-mentioned method has the following surface characteristics: black cylindrical particles, particle size 0.9mm to 1.2mm, particle length 2mm to 6mm, and compressive strength >70N.
[0055] In an exemplary embodiment, when the above-mentioned carbon molecular sieve is loaded into a PSA nitrogen generator for testing, the air / nitrogen ratio increases as the nitrogen production concentration increases, for example, when the nitrogen production concentration is 99%, the air / nitrogen ratio is 2.1, and when the nitrogen production concentration is 99.9%, the air / nitrogen ratio is 4.6; when the nitrogen production concentration is 99.5%, the nitrogen production amount reaches 260Nm 3 / t.h to 330Nm 3 / t.h.
[0056] Example 2 Example 2 is a carbon molecular sieve prepared by the above-mentioned method for preparing carbon molecular sieve.
[0057] In an exemplary embodiment, the carbon molecular sieve of the present application has the following surface characteristics: black cylindrical particles, particle size 0.9mm to 1.2mm, particle length 2mm to 6mm, and compressive strength >70N.
[0058] In an exemplary embodiment, when the carbon molecular sieve of the present application is loaded into a PSA nitrogen generator for testing, the air / nitrogen ratio increases as the nitrogen concentration increases, for example, when the nitrogen concentration is 99%, the air / nitrogen ratio is 2.1, and when the nitrogen concentration is 99.9%, the air / nitrogen ratio is 4.6; when the nitrogen concentration is 99.5%, the nitrogen production reaches 260 Nm 3 / t.h to 330 Nm 3 / t.h.
[0059] Example 3 The biochar 200 kg is put into a roller mill for coarse grinding and crushing into biochar particles with a particle size of 1 mm to 5 mm, and then the biochar particles are soaked in a hydrochloric acid solution for 12 hours.
[0060] The hydrochloric acid content in the hydrochloric acid solution is 0.1 mol / L.
[0061] After soaking, the biochar particles are dried by centrifugal separation.
[0062] After drying, the biochar particles and 10 kg of urea are put into a roller mill and mixed uniformly, and the mixed material is loaded into a rotary furnace, which is slowly heated to 200°C for 6 hours of viscosity reduction modification, wherein the heating rate of the rotary furnace is 2°C / min.
[0063] After modification, the material is put into a ball mill for 16 hours of ball milling until the particle size of 50% of the biochar particles is 5 μm to 7 μm.
[0064] The biochar particles are put into a mixing and kneading machine, 20 kg of bio-pyrolysis oil and 120 kg of water are added and mixed uniformly, and then put into an extruder to extrude into cylindrical strip materials with a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
[0065] The cylindrical strip materials are loaded into a rotary furnace, heated to 700°C at a heating rate of 2°C / min and kept at a constant temperature for 2.5 hours.
[0066] After constant temperature, water vapor is introduced for activation, i.e. water vapor is introduced into the rotary furnace, the water vapor flow is 30 ml / min, and the activation time is 3 hours.
[0067] The temperature of the water vapor is 800°C.
[0068] After activation, benzene is introduced into the rotary furnace for deposition, the benzene flow is 5 ml / min, the deposition time is 10 hours, and the carbon molecular sieve is prepared.
[0069] The performance of the prepared carbon molecular sieve is as follows: Particle diameter (cylindrical): 0.9 mm to 1.2 mm; Bulk density: 640 g / l to 680 g / l; Compressive strength: > 70N.
[0070] The data obtained when the carbon molecular sieve was put into the PSA nitrogen generator for testing is shown in Table 1: .
[0071] Example 4 The biochar 200 kg was put into a roller mill for coarse grinding and crushing into biochar particles with a particle size of 1 mm to 5 mm, and then the biochar particles were soaked in a hydrochloric acid solution for 12 hours.
[0072] The hydrochloric acid content in the hydrochloric acid solution was 0.1 mol / L.
[0073] After soaking, centrifugal separation and drying were performed.
[0074] After centrifugal separation and drying, the biochar particles were mixed with 20 kg of urea in a roller mill, and the uniformly mixed material was loaded into a rotary furnace, which was slowly heated to 300°C for 4 hours of viscosity reduction modification, with a heating rate of 2°C / min.
[0075] After modification, the material was put into a ball mill for 20 hours of ball milling, until the particle size of the biochar particles was 3 μm to 5 μm, and then the ball milling was stopped.
[0076] The biochar particles were put into a mixing and kneading machine, 40 kg of bio-pyrolysis oil and 80 kg of water were added, and the mixture was uniformly kneaded, and then put into an extruder to be extruded into cylindrical strip materials with a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
[0077] The cylindrical strip materials were loaded into a rotary furnace, heated to 800°C at a heating rate of 7°C / min, and held at a constant temperature for 1 hour.
[0078] After the constant temperature was reached, water vapor was introduced for activation, i.e. water vapor was introduced into the rotary furnace, with a water vapor flow rate of 45 ml / min, and activated for 1.5 hours.
[0079] The temperature of the water vapor was 800°C.
[0080] After activation was completed, benzene was introduced into the rotary furnace for deposition, with a benzene flow rate of 20 ml / min, and a deposition time of 4 hours, to obtain a carbon molecular sieve.
[0081] The performance of the carbon molecular sieve obtained is as follows: Particle diameter (cylindrical): 0.9 mm to 1.2 mm; Bulk density: 640 g / l to 680 g / l; Compressive strength: > 70N.
[0082] The data obtained when the carbon molecular sieve was put into the PSA nitrogen generator for testing is shown in Table 2: .
[0083] Example 5 The biochar 200 kg was put into a roller mill for coarse grinding to biochar particles with a particle size of 1 mm to 5 mm, and then the biochar particles were soaked in a hydrochloric acid solution for 12 hours.
[0084] The hydrochloric acid content in the hydrochloric acid solution was 0.1 mol / L.
[0085] After soaking, the biochar particles were dried by centrifugal separation.
[0086] After centrifugal separation and drying, the biochar particles were mixed with 30 kg of urea in a roller mill, and the mixture was loaded into a rotary furnace and slowly heated to 400°C for 2 hours of viscosity reduction modification, with a heating rate of 2°C / min.
[0087] After modification, the material was put into a ball mill for 24 hours of ball milling, and the ball milling was stopped when 50% of the biochar particles had a particle size of 3 μm to 5 μm.
[0088] The biochar particles were put into a mixing machine, 80 kg of bio-pyrolysis oil and 60 kg of water were added, and the mixture was mixed evenly. After heating, it was put into an extruder to form cylindrical strip materials with a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
[0089] The cylindrical strip materials were loaded into a rotary furnace and heated to 850°C at a heating rate of 10°C / min and held for 0.5 hours.
[0090] After holding, water vapor was introduced for activation, i.e. water vapor was introduced into the rotary furnace, with a water vapor flow rate of 60 ml / min, and activated for 0.5 hours.
[0091] The temperature of the water vapor was 800°C.
[0092] After activation, benzene was introduced into the rotary furnace for deposition, with a benzene flow rate of 40 ml / min, and a deposition time of 1 hour, to produce carbon molecular sieves.
[0093] The performance of the carbon molecular sieves produced was as follows: Particle diameter (cylindrical): 0.9 mm to 1.2 mm; Bulk density: 640 g / l to 680 g / l; Compressive strength: > 70 N.
[0094] When the carbon molecular sieves were put into a PSA nitrogen generator for testing, the data obtained were as shown in Table 3: .
[0095] Example 6 The biochar 200 kg is put into a roller mill to be roughly ground into biochar particles with a particle size of 1 mm to 5 mm, and then the biochar particles are soaked in a hydrochloric acid solution for 12 hours.
[0096] The hydrochloric acid content in the hydrochloric acid solution is 0.1 mol / L.
[0097] After the soaking is completed, the biochar coarse powder is dried by centrifugal separation.
[0098] After the centrifugal separation and drying, the biochar coarse powder is mixed with 15 kg of urea in a roller mill, and the uniformly mixed material is loaded into a rotary furnace, which is slowly heated to 400°C for 6 hours of viscosity reduction modification, wherein the heating rate of the rotary furnace is 2°C / min.
[0099] After the modification is completed, the material is put into a ball mill for 18 hours of ball milling, and the ball milling is stopped when 50% of the biochar particles have a particle size of 9 μm to 12 μm.
[0100] The powder is put into a mixing and kneading machine, 65 kg of bio-pyrolysis oil and 90 kg of water are added, and the mixture is uniformly kneaded, and then the hot mixture is put into an extruder to be extruded into cylindrical strip materials with a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
[0101] The cylindrical strip materials are loaded into a rotary furnace, which is heated to 775°C at a heating rate of 5°C / min and kept at a constant temperature for 2 hours.
[0102] After the constant temperature is completed, water vapor is introduced for activation, i.e., the water vapor is introduced into the rotary furnace, the water vapor flow rate is 50 ml / min, and the activation is performed for 1.5 hours.
[0103] The temperature of the water vapor is 800°C.
[0104] After the activation is completed, benzene is introduced into the rotary furnace for deposition, the benzene flow rate is 30 ml / min, the deposition time is 4.5 hours, and the carbon molecular sieve is prepared.
[0105] The performance of the prepared carbon molecular sieve is as follows: Particle diameter (cylindrical shape): 0.9 mm to 1.2 mm; Bulk density: 640 g / l to 680 g / l; Compressive strength: > 70 N.
[0106] When the carbon molecular sieve is put into a PSA nitrogen making machine for testing, the obtained data is shown in Table 4: .
[0107] Example 7 The biochar 200 kg is put into a wheel mill to be coarsely ground into biochar particles with a particle size of 1 mm to 5 mm, and then the biochar particles are soaked in a hydrochloric acid solution for 12 hours.
[0108] The hydrochloric acid content in the hydrochloric acid solution is 0.1 mol / L.
[0109] After the soaking is completed, the centrifugal separation and drying are performed again.
[0110] After the centrifugal separation and drying, the biochar coarse powder and 20 kg of urea are put into a wheel mill to be uniformly blended, and the uniformly blended material is loaded into a rotary furnace, which is slowly heated to 325°C for viscosity reduction modification for 2.5 hours, wherein the heating rate of the rotary furnace is 2°C / min.
[0111] After the modification is completed, the material is put into a ball mill for ball milling for 22 hours, and the ball milling is stopped when 50% of the biochar particles have a particle size of 4 μm to 6 μm.
[0112] The powder is put into a mixing and kneading machine, 70 kg of bio-pyrolysis oil and 70 kg of water are added, and the mixture is uniformly kneaded, and then the mixture is put into an extruder to be extruded into cylindrical strip materials with a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
[0113] The cylindrical strip materials are loaded into a rotary furnace, which is heated to 750°C at a heating rate of 6°C / min and kept at a constant temperature for 1.5 hours.
[0114] After the constant temperature is completed, water vapor is introduced for activation, i.e., the water vapor is introduced into the rotary furnace, the water vapor flow rate is 45 ml / min, and the activation is performed for 1.5 hours.
[0115] The temperature of the water vapor is 800°C.
[0116] After the activation is completed, benzene is introduced into the rotary furnace for deposition, the benzene flow rate is 25 ml / min, the deposition time is 5 hours, and the carbon molecular sieve is prepared.
[0117] The performance of the prepared carbon molecular sieve is as follows: Particle diameter (cylindrical shape): 0.9 mm to 1.2 mm; Bulk density: 640 g / l to 680 g / l; Compressive strength: > 70 N.
[0118] When the carbon molecular sieve is put into a PSA nitrogen making machine for testing, the obtained data are shown in Table 5: .
[0119] Those skilled in the art can understand that the above are only the preferred embodiments of the present application, and are not used to limit the present application, and although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method for preparing carbon molecular sieves, characterized in that, include: Remove inorganic matter from biochar to less than 100 ppm; The biochar and urea are mixed and placed in a reactor to react and crosslink into a macromolecular structure. The macromolecular structure was ground into bio-coke particles; The bio-coke particles are mixed with bio-pyrolysis oil and water and then extruded to obtain carbon molecular sieve extruded material. The carbon molecular sieve extruded material is carbonized in a rotary kiln; After the carbonization is completed, steam is introduced into the rotary kiln for activation; After the activation is completed, benzene is passed into the rotary furnace for deposition to obtain carbon molecular sieves.
2. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of removing inorganic matter from biochar to less than 100 ppm is to obtain it by making biochar particles, soaking them in hydrochloric acid solution, and then drying them. The biochar particles have a particle size of 1 mm to 5 mm; The hydrochloric acid content in the hydrochloric acid solution is 0.1 mol / L.
3. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of mixing the biochar and urea and then reacting and crosslinking them in a reactor to form a macromolecular structure includes: The mass ratio of the biochar to the urea is 1:0.05 to 0.
15.
4. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of mixing the biochar and urea and then reacting and crosslinking them in a reactor to form a macromolecular structure further includes: The operating temperature of the reactor is 200 to 400°C, and the reaction time is 2 to 6 hours.
5. The method for preparing carbon molecular sieves according to claim 1, characterized in that, In the step of grinding the macromolecular structure into biochar particles, 50% of the biochar particles have a particle size of 3 μm to 12 μm.
6. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of mixing the biochar particles with bio-pyrolysis oil and water and extruding them to obtain carbon molecular sieve extruded material includes: The mass ratio of the bio-coke, the bio-pyrolysis oil, and the water is 1:0.1 to 0.4:0.3 to 0.
6.
7. The method for preparing carbon molecular sieves according to claim 6, characterized in that, The carbon molecular sieve extruded material has a particle size of 1.2 mm to 2.0 mm and a length of 1 mm to 7 mm.
8. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of carbonizing the carbon molecular sieve extruded material in a rotary kiln includes: The rotary kiln is heated to 700°C to 850°C at a heating rate of 2°C / min to 10°C / min, and then kept at the temperature at which heating was stopped for 0.5 hours to 2.5 hours.
9. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of activating the rotary kiln by introducing steam includes: The flow rate of the water vapor is 30 ml / min to 60 ml / min, and the activation time is 0.5 hours to 3 hours.
10. The method for preparing carbon molecular sieves according to claim 1, characterized in that, The step of passing benzene into the rotary furnace for deposition to obtain carbon molecular sieves includes: The flow rate of benzene is from 5 ml / min to 40 ml / min, and the deposition time is from 1 hour to 10 hours.
11. A carbon molecular sieve, characterized in that, It is prepared by the method of any one of claims 1 to 10 for preparing carbon molecular sieves.