An adsorbent material for direct capture of carbon dioxide in air and its preparation method and application

Abstract

The application belongs to the technical field of adsorbing materials, and particularly relates to an adsorbing material, a preparation method and application thereof, and a method for capturing low-concentration CO2 in air. The adsorbing material provided by the application comprises an adsorbing base and organic amine loaded on the surface of the adsorbing base; the adsorbing base comprises macroporous adsorbing resin, the pore volume of the adsorbing base is 0.3-0.9 mL / g, the specific surface area is 300-800 m 2 / g, and the average pore radius is 15-19 Å; the organic amine comprises polyethylene imine or polyethylene polyamine. The macroporous adsorbing resin with low price is used as a carrier to load the organic amine active component, so that the adsorbing capacity is improved and the cost of the adsorbing material is reduced. The adsorbing material provided by the application can efficiently adsorb low-concentration carbon dioxide in the environment in a humidified environment.

Description

Technical Field

[0001] This invention belongs to the field of adsorption material technology, specifically relating to an adsorption material, its preparation method and application, and a method for capturing carbon from low concentrations of CO2 in the air. Background Technology

[0002] With the development of human society, the demand for energy has increased year by year. For the past few decades, the main energy source relied upon by humankind has been fossil fuels. The continued use of fossil fuels has led to a continuous rise in the concentration of carbon dioxide (CO2) in the atmosphere. CO2 is a major greenhouse gas in the atmosphere, contributing to the continuous rise in global average temperature. Global climate change has become a pressing issue that urgently needs to be addressed. Because carbon capture and storage (CCS) technology can effectively collect, store, or utilize CO2 emitted from production and daily life, this technology has attracted widespread research interest. Large power plants and chemical plants are important sources of CO2 emissions, emitting high concentrations of CO2. The main method used for flue gas carbon capture is organic amine solution absorption. However, in transportation, industrial production, and civil facilities, equipment directly emits CO2 into the air. The emission sources are dispersed, and although the total emissions are large, the concentration of carbon dioxide in the flue gas is low. Therefore, existing conventional flue gas carbon capture methods cannot effectively capture these low-concentration CO2. Furthermore, because power plants burn fossil fuels, flue gas carbon capture technology can only reduce CO2 emissions, not lower the concentration of CO2 in the atmosphere. To address the above shortcomings, Direct Air Capture (DAC) technology has emerged. DAC does not require proximity to CO2 emission sources and is not limited by the scale of CO2 emissions. It can effectively solve the problem of dispersed CO2 emissions, making it a highly promising negative carbon emission technology. Furthermore, it can enrich CO2 for various facilities that require it anytime, anywhere. It is worth noting that low-concentration CO2 capture technologies (below 5000 ppm) have already found a few applications (diving, mining, anesthesia, etc.); however, these technologies are relatively expensive and cannot meet the needs of controlling atmospheric CO2 levels. To achieve large-scale application of DAC technology, we need DAC materials with high capture capacity, fast adsorption-desorption rates, sustainable operation, and low cost. Summary of the Invention

[0003] In view of this, the present invention provides an adsorbent material, its preparation method and application, and a method for carbon capture of low concentration CO2 in the air. The adsorbent material provided by the present invention can efficiently adsorb low concentrations of carbon dioxide in the environment and can be regenerated and recycled.

[0004] To address the aforementioned technical problems, the present invention provides an adsorption material comprising an adsorption matrix and an organic amine loaded on the surface of the adsorption matrix;

[0005] The adsorption matrix comprises a macroporous adsorption resin, wherein the pore volume of the adsorption matrix is ​​0.3~0.9 mL / g and the specific surface area is 300~800 m². 2 / g, with an average pore radius of 15~19Å;

[0006] The organic amines include polyethyleneimine or polyethylene polyamine.

[0007] Preferably, the organic amine accounts for 40-70% of the mass percentage of the adsorbent material.

[0008] Preferably, the macroporous adsorption resin includes macroporous adsorption resin X-5, macroporous adsorption resin HP20, or macroporous adsorption resin DA201.

[0009] Preferably, the polyethylene polyamine includes one or more of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and hexaethyleneheptamine.

[0010] The present invention also provides a method for preparing the adsorbent material described in the above technical solution, comprising the following steps:

[0011] Organic amines are dissolved in a solvent to obtain organic amine solutions;

[0012] The organic amine solution and macroporous adsorption resin are mixed to obtain the adsorption material.

[0013] Preferably, the solvent includes methanol, ethanol, or water.

[0014] Preferably, the organic amine solution has a mass concentration of 0.1~0.25 g / mL.

[0015] Preferably, the mixing is carried out under stirring conditions, and the stirring time is 0.8~1.2h.

[0016] The present invention also provides the application of the adsorption material described in the above technical solution or the adsorption material prepared by the preparation method described in the above technical solution in the adsorption and capture of carbon dioxide.

[0017] The present invention also provides a method for capturing low concentrations of CO2 in the air using the adsorbent material described in the above technical solution or the adsorbent material prepared by the preparation method described in the above technical solution, comprising the following steps:

[0018] After placing the adsorbent material in a fixed-bed reactor, the gas to be adsorbed is introduced to perform carbon dioxide adsorption.

[0019] The temperature of the adsorption environment is 20~35℃, and the relative humidity is 10~90%.

[0020] The volume concentration of carbon dioxide in the adsorption system is 300~3000ppm.

[0021] This invention provides an adsorption material comprising an adsorption matrix and an organic amine supported on the surface of the adsorption matrix; the adsorption matrix comprises a macroporous adsorption resin, the pore volume of the adsorption matrix being 0.3~0.9 mL / g and the specific surface area being 300~800 m² / g. 2 / g, with an average pore radius of 15-19 Å; the organic amine includes polyethyleneimine or polyethylenepolyamine. This invention uses an inexpensive macroporous adsorption resin as a carrier to load the active organic amine component, thereby increasing adsorption capacity while reducing the cost of the adsorption material. The adsorption material provided by this invention can efficiently adsorb low concentrations of carbon dioxide from the air. Attached Figure Description

[0022] Figure 1 A schematic diagram of a device for adsorbing and capturing carbon dioxide;

[0023] Figure 2 The adsorption and desorption curves of the adsorbent materials prepared in Examples 1-3 are shown below.

[0024] Figure 3 The adsorption and desorption curves of the adsorbent materials prepared in Examples 4-6 are shown.

[0025] Figure 4 The adsorption and desorption curves of the adsorbent materials prepared in Examples 7-9 are shown.

[0026] Figure 5 The adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 4-6 are shown.

[0027] Figure 6 The adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 7-9 are shown.

[0028] Figure 7 The adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 1-3 are shown. Figures 2-7 In the diagram, (a) is the adsorption curve of the adsorbent material, and (b) is the desorption curve of the adsorbent material.

[0029] Figure 8 The adsorption and desorption curves of 50-TEPA / X-5 and 60-TEPA / HP20 for carbon dioxide in gases with different oxygen contents under different adsorption humidity conditions are shown.

[0030] Figure 9 The adsorption and desorption curves of carbon dioxide after 5 cycles of adsorption for 60-TEPA / HP20 and 50-PEI / HP20 are shown. Detailed Implementation

[0031] The present invention provides an adsorption material comprising an adsorption matrix and an organic amine loaded on the surface of the adsorption matrix.

[0032] In this invention, the adsorption matrix comprises a macroporous adsorption resin, preferably macroporous adsorption resin X-5, macroporous adsorption resin HP20, or DA201, and more preferably macroporous adsorption resin X-5. In this invention, the pore volume of the adsorption matrix is ​​0.3~0.9 mL / g, preferably 0.7~0.8 mL / g; the specific surface area of ​​the adsorption matrix is ​​300~800 m². 2 / g, preferably 650~750m 2 / g; the average pore radius of the adsorption matrix is ​​15~19 Å, preferably 16~18 Å. This invention limits the pore volume, specific surface area, and pore size of the adsorption matrix to within the above ranges to facilitate uniform loading of organic amines, thereby improving the adsorption of low-concentration carbon dioxide.

[0033] In this invention, the organic amine includes polyethyleneimine (PEI) or polyethylene polyamine, preferably polyethylene polyamine. In this invention, the polyethylene polyamine preferably includes one or more of diethylenetriamine, triethylenetetramine, tetraethylenepentamine (TEPA), pentaethylenehexamine, and hexaethyleneheptaamine, more preferably one of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and hexaethyleneheptaamine, and even more preferably tetraethylenepentamine.

[0034] In this invention, the organic amine accounts for 40-70% of the mass percentage of the adsorbent material, more preferably 50-60%. In this invention, the adsorbent material is preferably particulate, and the particle size of the adsorbent material is preferably 20-80 mesh, more preferably 40-60 mesh.

[0035] The present invention also provides a method for preparing the adsorbent material described in the above technical solution, comprising the following steps:

[0036] Organic amines are dissolved in organic solvents to obtain organic amine solutions;

[0037] The organic amine solution and macroporous adsorption resin are mixed to obtain the adsorption material.

[0038] This invention dissolves an organic amine in a solvent to obtain an organic amine solution. In this invention, the solvent preferably includes methanol, ethanol, or water, more preferably methanol. In this invention, the mass concentration of the organic amine solution is preferably 0.1~0.25 g / mL, more preferably 0.156~0.23 g / mL. In this invention, the dissolution is preferably carried out under stirring conditions, and the stirring time is preferably 8~12 min, more preferably 10 min. This invention does not have special requirements for the stirring speed, as long as complete dissolution is achieved.

[0039] After obtaining the organic amine solution, the present invention mixes the organic amine solution with a macroporous adsorption resin to obtain the adsorption material. In the present invention, the mixing process preferably includes: subjecting the macroporous adsorption resin to a first drying followed by grinding, sieving, and a second drying. In the present invention, the temperature of the first drying is preferably 90-110°C, more preferably 100°C; the drying time is preferably 10-14 hours, more preferably 12-13 hours. The present invention has no special requirements for the grinding process and conventional methods in the art can be used. In the present invention, the average particle size of the sieved product is preferably 40-60 mesh, more preferably 45-55 mesh. The present invention has no special requirements for the sieving process, as long as the desired particle size can be obtained. In the present invention, the temperature of the second drying is preferably 90-110°C, more preferably 100°C; the drying time is preferably 0.8-1.2 hours, more preferably 1 hour.

[0040] In this invention, the mass ratio of the macroporous adsorption resin to the organic amine is preferably 3~7:3~7, more preferably 6:4, 5:5, 4:6 or 3:7, and even more preferably 4:6.

[0041] In this invention, the mixing is preferably carried out under stirring conditions, and the stirring time is preferably 0.8~1.2h, more preferably 1h. This invention does not have special requirements for the stirring speed, as long as it ensures uniform mixing and complete loading.

[0042] In this invention, the mixed system is preferably in a uniform white state.

[0043] This invention achieves loading of organic amines into macroporous adsorption resins through mixing. Preferably, after mixing, the process further includes removing the solvent from the mixed system and then grinding to obtain the adsorbent material. Preferably, the mixed system is placed in a ventilated area and stirred to evaporate the solvent. This invention does not have specific limitations on the stirring speed and time, as long as the solvent is completely evaporated. This invention does not have special requirements for the grinding process; conventional methods in the art can be used. The product after solvent evaporation is a slightly viscous, white, uniform block material. This invention grinds the block material into powder. Preferably, after grinding, the process further includes sieving the ground product. Preferably, the mesh size of the sieve used for sieving is 20-80 mesh, more preferably 40-60 mesh.

[0044] The present invention also provides the application of the adsorption material described in the above technical solution or the adsorption material prepared by the preparation method described in the above technical solution in the adsorption and capture of carbon dioxide.

[0045] The present invention also provides a method for capturing low concentrations of CO2 in the air using the adsorbent material described in the above technical solution or the adsorbent material prepared by the preparation method described in the above technical solution, comprising the following steps:

[0046] After placing the adsorbent material in a fixed-bed reactor, the gas to be adsorbed is introduced to perform carbon dioxide adsorption.

[0047] In this invention, the pre-adsorption process preferably further includes activating the adsorbent material. The activation is preferably performed under vacuum or a nitrogen atmosphere, more preferably under a nitrogen atmosphere. This invention does not have a particular limitation on the vacuum level; any vacuum environment is acceptable. This invention preferably introduces nitrogen gas into the fixed-bed reactor to form a nitrogen atmosphere; the flow rate of the introduced nitrogen gas is preferably 380~420 mL / min, more preferably 400 mL / min. In this invention, the activation temperature is preferably 90~110℃, more preferably 100℃; the activation holding time is preferably 20~30 min, more preferably 25 min. This invention, through activation, can remove carbon dioxide and other impurities already adsorbed in the adsorbent material.

[0048] In this invention, the temperature of the adsorption environment is 20~35℃, preferably 25~30℃; the relative humidity of the adsorption environment is 10~90%, preferably 90%.

[0049] In this invention, the volume concentration of carbon dioxide in the adsorption system is 300~3000ppm, preferably 400~2000ppm.

[0050] In this invention, the flow rate of the gas to be adsorbed is preferably 380~420 mL / min, more preferably 400 mL / min.

[0051] In this invention, the adsorbent material is considered saturated when the carbon dioxide concentration at the outlet of the fixed reactor is equal to the carbon dioxide concentration at the inlet. This invention preferably regenerates the saturated adsorbent material. In this invention, the regeneration is preferably carried out in a fixed bed, and the regeneration temperature is preferably 75-100°C, more preferably 80-100°C. In this invention, the regeneration is preferably carried out under vacuum conditions or nitrogen purging conditions, more preferably under nitrogen purging conditions. In this invention, the vacuum degree is preferably 90-110 kPa, more preferably 100 kPa. In this invention, the nitrogen purging flow rate is preferably 380-420 mL / min, more preferably 400 mL / min. This invention achieves the regeneration and recycling of the adsorbent material by desorbing carbon dioxide from it under high-temperature conditions.

[0052] In this invention, Figure 1This is a schematic diagram of a device for adsorbing and capturing carbon dioxide. The humidity generator provides humidity to the fixed-bed reactor. The temperature and humidity of the fixed-bed reactor are detected by a temperature and humidity sensor. The carbon dioxide content in the gas after adsorption is detected by an infrared gas sensor (NDIR). The gas after adsorption is dried by a drying tube before entering the infrared gas sensor. Figure 1 The medium vacuum pump provides vacuum conditions for the regeneration process.

[0053] This invention utilizes a low-cost macroporous adsorption resin with specific pore volume, pore size, and specific surface area as the adsorbent carrier, and employs polyethylenepolyamines with high amino content and low molecular weight as organic amines. The material has a large specific surface area, rapid internal gas transport, and a high loading of active amino groups, resulting in a high adsorption capacity and rapid adsorption-desorption kinetics. The adsorption process is carried out in a humidified environment, enabling the material to achieve a maximum adsorption capacity of 5.4 mmol / g.

[0054] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0055] Example 1

[0056] 0.6 g of tetraethylenepentamine (TEPA) and 2.75 mL of methanol were stirred for 10 min to obtain a tetraethylenepentamine solution;

[0057] With a pore volume of 0.826 mL / g and a specific surface area of ​​749 m², 2 HP20 macroporous adsorption resin particles with an average pore radius of 16.9 Å and a diameter of 1 mm were dried at 100℃ for 12 h, then ground and sieved. The sieved particles with a particle size of 40~60 mesh were dried at 100℃ for 1 h to obtain dried HP20.

[0058] 0.4g of dried HP20 and tetraethylenepentamine solution were stirred and mixed in a closed environment for 1 hour to obtain a white slurry. The white slurry was placed in a ventilated place and stirred until the methanol evaporated completely, resulting in a slightly sticky white uniform block material. After grinding with a mortar and sieve, an adsorbent material with an average particle size of 50 mesh and a tetraethylenepentamine loading of 60% was obtained, denoted as 60-TEPA / HP20.

[0059] Examples 2-9

[0060] The adsorbent material was prepared according to the method of Example 1, with the differences shown in Table 1.

[0061] Comparative Examples 1-9

[0062] The adsorbent material was prepared according to the method of Example 1, with the differences shown in Table 1.

[0063] Table 1. Types and amounts of materials used in the preparation of adsorbent materials in Examples 1-9 and Comparative Examples 1-9

[0064]

[0065] Test Example 1

[0066] use Figure 1 The device shown was used to test the adsorption performance of the adsorbent materials prepared in Examples 1-9 and Comparative Examples 1-9 for carbon dioxide. The specific steps were as follows:

[0067] Step 1: 0.1g of adsorbent material is placed in a fixed-bed reactor and activated by nitrogen purging (400mL / min) at 100℃ for 25min to obtain activated adsorbent material;

[0068] Step 2: At room temperature (relative humidity 90%), the gas to be adsorbed is introduced into the fixed bed reactor at a flow rate of 400 mL / min until the carbon dioxide concentration at the outlet and the carbon dioxide concentration at the inlet (the concentration of carbon dioxide at the outlet is detected by NDIR) are equal. Then the gas to be adsorbed is stopped, and the adsorbent material is saturated.

[0069] The gas to be adsorbed is a mixture of carbon dioxide and nitrogen, and the concentration of carbon dioxide in the gas to be adsorbed is 400 ppm.

[0070] Step 3: When the adsorbent material needs to be recycled, the saturated adsorbent material can be regenerated. The fixed bed reactor is purged with nitrogen to desorb carbon dioxide from the saturated adsorbent material and obtain regenerated adsorbent material. The purging conditions are 100℃, 400mL / min pure nitrogen, and purging time of 25min.

[0071] The performance parameters of the adsorbent material, including carbon dioxide adsorption capacity, time to reach adsorption equilibrium, carbon dioxide desorption capacity, and time to reach desorption equilibrium, are listed in Table 2.

[0072] Table 2. Adsorption performance parameters of the adsorbent materials prepared in Examples 1-9 and Comparative Examples 1-9

[0073]

[0074] Based on the test results, carbon dioxide adsorption and desorption curves for each adsorbent material were plotted, such as... Figures 2-7 As shown, where Figure 2 The figures show the adsorption and desorption curves of the adsorbent materials prepared in Examples 1-3, where... Figure 3 The figures show the adsorption and desorption curves of the adsorbent materials prepared in Examples 4-6, where... Figure 4 The figures show the adsorption and desorption curves of the adsorbent materials prepared in Examples 7-9, where... Figure 5 The adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 4-6 are shown below. Figure 6 The adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 7-9 are shown below. Figure 7 The attached figures show the adsorption and desorption curves of the adsorbent materials prepared in Comparative Examples 1-3. (a) is the adsorption curve of the adsorbent material, and (b) is the desorption curve of the adsorbent material.

[0075] Combine Table 2 and Figures 2-7 It can be seen that when 400 ppm CO2 is initially introduced into the fixed-bed reactor, the adsorbent can effectively capture CO2 from the air, resulting in an outlet CO2 concentration of approximately 0. The slope of the adsorption curve remains constant. As a certain amount of CO2 is absorbed, the outlet CO2 concentration gradually increases, and the slope of the adsorption curve gradually decreases. During desorption, CO2 desorption begins to be observed when the fixed-bed reactor is heated to 80℃, and is completed when heated to 100℃. Adsorbents with faster adsorption kinetics tend to have faster desorption rates. Amine supports with different pore sizes exhibit different optimal TEPA loading ratios. When the TEPA content is higher or lower than the optimal content, the adsorption capacity of the material decreases. The optimized materials were 60-TEPA / DA201, 50-TEPA / X-5, 50-TEPA / SP700, 50-TEPA / XAD16, 60-TEPA / HP20, and 50-TEPA / D101. The adsorption capacity of 60-TEPA / HP20 was 4.112 mmol g⁻¹, reaching adsorption equilibrium within 4106 s. The desorption capacity of this adsorbent was 3.906 mmol g⁻¹. -1 The adsorption equilibrium was reached at 1493 s. Resin materials with lower TEPA content tend to have faster adsorption and desorption kinetics. This phenomenon is attributed to the better dispersion and inhibition of aggregation of TEPA, resulting in a better CO2 mass transfer effect.

[0076] Test Example 2

[0077] The adsorption performance of 50-TEPA / X-5 and 60-TEPA / HP20 was tested according to the method in Test Example 1, except that the gases to be adsorbed were a mixture of carbon dioxide and air (400ppmCO2 / Air) or a mixture of carbon dioxide and nitrogen (400ppmCO2 / N2), with a carbon dioxide concentration of 400ppm in the mixture; the adsorption was carried out in environments with relative humidity (RH) of 10% and 90%, respectively.

[0078] The performance parameters of the adsorbent material, including carbon dioxide adsorption capacity, time to reach adsorption equilibrium, carbon dioxide desorption capacity, and time to reach desorption equilibrium, are listed in Table 3.

[0079] Table 3 Adsorption performance parameters of 50-TEPA / X-5 and 60-TEPA / HP20 under different adsorption conditions

[0080]

[0081] Based on the test results, adsorption and desorption curves of various adsorbent materials for carbon dioxide in gases with different oxygen contents under different adsorption humidity conditions were plotted, such as... Figure 8 As shown. (Combined with Table 3 and...) Figure 8 It can be seen that the adsorption rate decreases with increasing relative humidity, prolonging the time required for adsorption to reach equilibrium. The underlying mechanism is that water, being a small molecule, can penetrate the interior of amines by forming hydrogen bonds with amino groups, inhibiting the accumulation of amino groups within the amine. Furthermore, water blocks pores through PEI (polyethyleneimine), thereby promoting CO2 diffusion within the amine and increasing the proportion of active amino groups in the material. In addition, water can participate in the reaction between amino groups and CO2 to form bicarbonates. Therefore, the utilization efficiency of amino groups can be doubled, thus increasing the adsorption capacity of the material.

[0082] Test Example 3

[0083] use Figure 1 The device shown is used to test the adsorption performance of 60-TEPA / HP20 or 50-PEI / HP20 for carbon dioxide. The specific steps are as follows:

[0084] Step 1: Place 0.1g of adsorbent material into a fixed-bed reactor and keep it at 100℃ for 25min under a nitrogen atmosphere (purging with nitrogen at a flow rate of 400mL / min) to obtain activated adsorbent material;

[0085] Step 2: At room temperature (relative humidity 90%), the gas to be adsorbed is introduced into the fixed bed reactor at a flow rate of 400 mL / min until the carbon dioxide concentration at the outlet and the carbon dioxide concentration at the inlet (the concentration of carbon dioxide at the outlet is detected by NDIR) are equal. Then the gas to be adsorbed is stopped, and the adsorbent material is saturated.

[0086] The gas to be adsorbed is a mixture of carbon dioxide and air, and the concentration of carbon dioxide in the gas to be adsorbed is 400 ppm.

[0087] Step 3: Regenerate the adsorbent material that has become saturated; after evacuating the fixed-bed reactor to a vacuum of 100 kPa, heat it to 100°C and hold it at that temperature for 25 min to desorb carbon dioxide and obtain the regenerated adsorbent material.

[0088] Step 4: Use the regenerated adsorbent material to repeat the adsorption process, repeating steps 2 and 3 for 5 cycles of adsorption.

[0089] The performance parameters of the adsorbent material, including carbon dioxide adsorption capacity, time to adsorption equilibrium, carbon dioxide desorption capacity, and time to desorption equilibrium, obtained from five cycles of adsorption testing, are listed in Table 4.

[0090] Table 4. Adsorption performance parameters of 60-TEPA / HP20 and 50-PEI / HP20 cyclic adsorption.

[0091]

[0092] Based on the test results, adsorption and desorption curves of carbon dioxide were plotted for five cycles of adsorption by the adsorbent material, as follows: Figure 9 As shown. (Combined with Table 4 and...) Figure 9 It can be seen that the initial adsorption capacity of the 60-TEPA / HP20 material in the first cycle is 5.328 mmol g. -1 The desorption capacity is 4.790 mmol g. -1 As the material underwent multiple cycles, the adsorption capacity of 60-TEPA / HP20 gradually decreased, with an average decrease of 3.3% per cycle. After five cycles, the material retained 87% of its initial adsorption capacity. Oily deposits were observed at the outlet of the fixed-bed reactor after each desorption process. These were identified as TEPA that had escaped from within the resin material. In contrast, although the CO2 adsorption capacity was relatively low (3.431 mmol g), the adsorption capacity of 60-TEPA / HP20 was significantly reduced. -1 However, no performance degradation or oily deposits were observed during the 50-PEI / HP20 cycling process. After five cycles, the adsorption performance of the material showed no decline. The adsorbent material provided by this invention exhibits excellent regeneration performance.

[0093] The present invention uses a low-cost, low-density, high-pore-volume, and high-specific-surface-area macroporous adsorption resin as an adsorbent carrier to load polyethyleneimine or polyethylene polyamine substances to obtain an adsorption material with high adsorption capacity, low desorption temperature, and fast adsorption-desorption kinetics, which can adsorb low concentrations of carbon dioxide in the air.

[0094] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An adsorbent material, characterized in that, Includes an adsorption matrix and an organic amine supported on the surface of the adsorption matrix; The adsorption matrix includes a macroporous adsorption resin, specifically HP20 macroporous adsorption resin. The pore volume of the adsorption matrix is ​​0.3–0.9 mL / g, and the specific surface area is 300–800 m². 2 / g, with an average pore radius of 16~18Å; The organic amine is tetraethylenepentamine; the organic amine accounts for 60% of the mass percentage of the adsorbent material.

2. The method for preparing the adsorbent material according to claim 1, comprising the following steps: Organic amines are dissolved in a solvent to obtain organic amine solutions; The organic amine solution and macroporous adsorption resin are mixed to obtain the adsorption material.

3. The preparation method according to claim 2, characterized in that, The solvent includes methanol, ethanol, or water.

4. The preparation method according to claim 2 or 3, characterized in that, The organic amine solution has a mass concentration of 0.1~0.25 g / mL.

5. The preparation method according to claim 2, characterized in that, The mixing is carried out under stirring conditions, and the stirring time is 0.8~1.2h.

6. The application of the adsorbent material according to claim 1 or the adsorbent material prepared by the preparation method according to any one of claims 2 to 5 in the adsorption and capture of carbon dioxide.

7. A method for capturing low-concentration CO2 in the air using the adsorbent material according to claim 1 or the adsorbent material prepared by the preparation method according to any one of claims 2 to 5, comprising the following steps: After placing the adsorbent material in a fixed-bed reactor, the gas to be adsorbed is introduced to perform carbon dioxide adsorption. The temperature of the adsorption environment is 20~35℃, and the relative humidity is 10~90%. The volume concentration of carbon dioxide in the adsorption system is 300~3000ppm.

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