Porous adsorption material and preparation method thereof

Abstract

The invention relates to the field of adsorption materials, and particularly discloses a porous adsorption material and a preparation method thereof. The porous adsorption material comprises alpha-Al2O3, the surface of the alpha-Al2O3 is modified by an active liquid, the active liquid is one of a p-aminobenzene sulfonic acid solution, a p-aminotoluene solution and a p-aminophenylacetic acid solution, and the mass ratio of the alpha-Al2O3 to the active liquid is 1: (3-8); alpha-Al2O3 is modified by niobium pentachloride in advance, and the preparation method comprises the following specific steps: mixing water, niobium pentachloride and alpha-Al2O3, uniformly stirring, carrying out suction filtration, heating and drying to obtain modified alpha-Al2O3; the alpha-Al2O3 crystal form is adopted to provide a rapid diffusion channel and improve the adsorption effect, meanwhile, the p-aminobenzene sulfonic acid solution, the p-aminotoluene solution and the p-aminophenylacetic acid solution are adopted to modify alpha-Al2O3, active molecules are introduced, and strong chemical acting forces such as ion exchange and coordinate bonds are provided, so that adsorption is firmer, the capacity is increased, and the adsorption capacity of the adsorption material is improved.

Description

Technical Field

[0001] This application relates to the field of adsorption materials, and in particular to a porous adsorption material and its preparation method. Background Technology

[0002] In the field of adsorbent technology, with the rapid development of industry, the demand for adsorption treatment of various harmful gases is increasing daily. Adsorbents play a vital role in many fields such as environmental protection, chemical production, and air purification. Highly efficient adsorbents can effectively remove pollutants from the air, ensuring the safety of the production environment and the health of personnel, while also helping to improve the quality and purity of chemical products.

[0003] In existing technologies, a common method for preparing adsorbents is to modify the pore structure and surface properties of inorganic materials through high-temperature sintering to enhance their adsorption capacity, although inorganic materials possess high strength and high thermal stability. However, the surface chemical properties of inorganic materials are relatively inert, relying mainly on physical adsorption and limited surface hydroxyl interactions, resulting in poor adsorption selectivity and insufficient adsorption capacity and binding force for many organic compounds. Summary of the Invention

[0004] To address the shortcomings of existing adsorption materials, this application provides a porous adsorption material and its preparation method.

[0005] In a first aspect, this application provides a porous adsorption material, which adopts the following technical solution: A porous adsorbent material includes α-Al2O3, the surface of which is modified with an active liquid, wherein the active liquid is one of p-aminobenzenesulfonic acid solution, p-aminotoluene solution, and p-aminophenylacetic acid solution, and the mass ratio of α-Al2O3 to the active liquid is 1:(3-8); the α-Al2O3 is pre-modified with niobium pentachloride, comprising the following specific steps: mixing water, niobium pentachloride and α-Al2O3, stirring evenly and filtering, heating and drying to obtain modified α-Al2O3.

[0006] By adopting the above technical solution, compared with other crystal forms, the α-Al₂O₃ crystal form has higher hardness and thermal and chemical stability, which can improve the structural stability of the adsorbent material in harsh environments. At the same time, the α-Al₂O₃ crystal form has more abundant mesopores, macropores and other channels and a high specific surface area, which can provide rapid diffusion channels and improve the adsorption effect.

[0007] Modification of α-Al₂O₃ by p-aminobenzenesulfonic acid solution, p-aminotoluene solution, and p-aminophenylacetic acid solution can form a high density of adsorption sites on the α-Al₂O₃ surface, thereby increasing the adsorption capacity of the adsorbent material. On the other hand, p-aminobenzenesulfonic acid solution, p-aminotoluene solution, and p-aminophenylacetic acid solution can introduce active molecules into the alumina surface, providing strong chemical forces such as ion exchange and coordination bonds, promoting stronger adsorption and increased capacity.

[0008] Modification of α-Al₂O₃ particles with niobium pentachloride reduces particle stacking, promotes uniform pore distribution in α-Al₂O₃, and thus improves the stability of α-Al₂O₃ adsorption performance. Niobium oxide exhibits strong interactions with the α-Al₂O₃ surface, enhancing its acidity and adsorption sites, thereby improving the adsorption of organic matter through hydrogen bonding or acid-base interactions and ultimately increasing the adsorption efficiency of the material.

[0009] Preferably, the particle size of the α-Al2O3 is 10-30 μm.

[0010] Preferably, the preparation method of α-Al2O3 includes the following specific steps: Boehmite powder was mixed with water to form a suspension. The pH of the suspension was adjusted, and the suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder, and finally calcined at high temperature to obtain α-Al2O3.

[0011] By adopting the above technical solution, the sol can be spray-dried into powder to obtain nano-sized alumina particles, forming a smooth, amorphous spherical surface. It can form a stable α phase by calcination at high temperature. The dense α-Al2O3 formed at high temperature has strong structural stability.

[0012] Preferably, nitric acid is used to adjust the pH of the suspension to 3-4.

[0013] By adopting the above technical solution, the pH range of 3-4 can promote better spheroidization of the product, while ensuring that the prepared α-Al2O3 has stable adsorption performance.

[0014] Preferably, the solid content of the suspension is 20-30%.

[0015] Preferably, the calcination temperature is 1100-1200℃.

[0016] By adopting the above technical solution, within a temperature range of 1100-1200℃, γ-Al2O3 is stably and completely converted into α-Al2O3, which can generate crystal grains with better crystallinity and improve the structural stability and compactness of the adsorbent material.

[0017] Preferably, the mass ratio of niobium pentachloride to α-Al2O3 is (0.8-1.2):3.

[0018] Secondly, this application provides a method for preparing a porous adsorbent material, which adopts the following technical solution: A method for preparing a porous adsorbent material includes the following specific steps: immersing α-Al2O3 in an active liquid, removing the α-Al2O3 after immersion at room temperature and pressure, and drying it to obtain a porous adsorbent material.

[0019] By adopting the above technical solution, the modified α-Al2O3 by the active liquid can promote the preparation of porous adsorbent materials with better adsorption capacity.

[0020] Preferably, the soaking time is 2-4 hours.

[0021] In summary, this application has the following beneficial effects: 1. Because the α-Al₂O₃ crystal form used in this application possesses high hardness and thermal and chemical stability, along with abundant pores and a high specific surface area, it enhances the adsorption effect and adsorption capacity. Modification of α-Al₂O₃ using p-aminobenzenesulfonic acid solution, p-aminotoluene solution, and p-aminophenylacetic acid solution creates a high density of adsorption sites on the α-Al₂O₃ surface, introducing active molecules and providing strong chemical interactions such as ion exchange and coordination bonds, thus promoting stronger adsorption and increased capacity.

[0022] 2. In this application, niobium pentachloride is used to modify α-Al2O3 particles to reduce the stacking of particles, promote the uniform distribution of pores on the surface of α-Al2O3, and niobium oxide can enhance the acidity and adsorption sites on the surface of α-Al2O3, promote the adsorption of organic matter by hydrogen bonds or acid-base interactions, and improve the adsorption capacity of the adsorption material. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the embodiments.

[0024] All raw materials used in the examples are commercially available. Example Example 1

[0025] This embodiment provides a porous adsorption material, including α-Al2O3, wherein the surface of α-Al2O3 is modified with an active liquid.

[0026] The preparation method of porous adsorbent materials includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0027] S2: α-Al₂O₃ was immersed in an active solution with a mass ratio of 1:5. The average particle size of α-Al₂O₃ was 20 μm. The active solution was a 10% (w / w) aqueous solution of p-aminobenzenesulfonic acid. After immersion at room temperature and pressure for 3 hours, the α-Al₂O₃ was removed and dried under vacuum at 80°C to obtain a porous adsorbent material.

[0028] Example 2

[0029] The difference between Example 2 and Example 1 lies in the preparation method of the porous adsorbent material, which includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0030] S2: α-Al₂O₃ was immersed in an active solution with a mass ratio of 1:3. The average particle size of α-Al₂O₃ was 20 μm. The active solution was a 10% (w / w) aqueous solution of p-aminobenzenesulfonic acid. After immersion at room temperature and pressure for 3 hours, the α-Al₂O₃ was removed and dried under vacuum at 80°C to obtain a porous adsorbent material.

[0031] Example 3 The difference between Example 3 and Example 1 lies in the preparation method of the porous adsorbent material, which includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0032] S2: α-Al2O3 is soaked in an active liquid with a mass ratio of 1:8. The average particle size of α-Al2O3 is 20μm. The active liquid is a 10% p-aminobenzenesulfonic acid aqueous solution. After soaking at room temperature and pressure for 3 hours, α-Al2O3 is removed and dried under vacuum at 80℃ to prepare a porous adsorbent material.

[0033] Example 4 The difference between Example 4 and Example 1 lies in the preparation method of the porous adsorbent material, which includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0034] S2: α-Al2O3 was soaked in an active liquid with a mass ratio of 1:5 between α-Al2O3 and the active liquid. The average particle size of α-Al2O3 was 20 μm. The active liquid was a 10% p-aminotoluene solution-methanol solution. After soaking at room temperature and pressure for 3 hours, α-Al2O3 was removed and dried under vacuum at 80°C to prepare a porous adsorbent material.

[0035] Example 5 The difference between Example 5 and Example 1 lies in the preparation method of the porous adsorbent material, which includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0036] S2: α-Al2O3 is soaked in an active liquid with a mass ratio of 1:5 between α-Al2O3 and the active liquid. The average particle size of α-Al2O3 is 20 μm. The active liquid is a 10% p-aminophenylacetic acid aqueous solution. After soaking at room temperature and pressure for 3 hours, α-Al2O3 is removed and dried under vacuum at 80°C to prepare a porous adsorbent material.

[0037] Example 6 The difference between Example 6 and Example 1 lies in the preparation method of the porous adsorbent material, which includes the following specific steps: S1: Pseudoboehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 6 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0038] S2: α-Al2O3 is soaked in an active liquid with a mass ratio of 1:5 between α-Al2O3 and the active liquid. The average particle size of α-Al2O3 is 20 μm. The active liquid is a 10% (w / w) aqueous solution of p-aminobenzenesulfonic acid. After soaking at room temperature and pressure for 3 hours, α-Al2O3 is removed and dried under vacuum at 80°C to prepare a porous adsorbent material.

[0039] Example 7 The difference between Example 7 and Example 1 is that α-Al2O3 was modified with niobium pentachloride beforehand.

[0040] The preparation method of porous adsorbent materials includes the following specific steps: S1: Boehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3.

[0041] S2: Mix water, niobium pentachloride and α-Al2O3 to form a mixed solution. The mass ratio of niobium pentachloride to α-Al2O3 is 1:3. The total mass of niobium pentachloride and α-Al2O3 accounts for 5% of the mixed solution. Stir evenly and filter. Heat to 160℃ and dry for 1.5h to obtain modified α-Al2O3.

[0042] S3: α-Al₂O₃ was immersed in an active solution with a mass ratio of 1:5. The average particle size of α-Al₂O₃ was 20 μm. The active solution was a 10% (w / w) aqueous solution of p-aminobenzenesulfonic acid. After immersion at room temperature and pressure for 3 hours, the α-Al₂O₃ was removed and dried under vacuum at 80°C to obtain a porous adsorbent material.

[0043] Example 8 The difference between Example 8 and Example 7 is that the mass ratio of niobium pentachloride and α-Al2O3 is 0.8:3.

[0044] Example 9 The difference between Example 9 and Example 7 is that the mass ratio of niobium pentachloride and α-Al2O3 is 1.2:3.

[0045] Comparative Example Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the α-Al2O3 surface in the porous adsorbent material is not modified.

[0046] The preparation method of porous adsorbent materials includes the following specific steps: S1: Pseudoboehmite powder was mixed with water to form a suspension with a solid content of 25%. The pH of the suspension was adjusted to 3 using nitric acid. The suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder and finally calcined at 1100℃ to obtain α-Al2O3, thus preparing a porous adsorbent material.

[0047] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that an equal amount of γ-Al2O3 was used instead of α-Al2O3 in the raw materials of the porous adsorbent material.

[0048] The preparation method of porous adsorbent materials includes the following specific steps: γ-Al₂O₃ was immersed in an active solution with a mass ratio of 1:5. The average particle size of the γ-Al₂O₃ was 20 μm. The active solution was a 10% (w / w) aqueous solution of p-aminobenzenesulfonic acid. After immersion at room temperature and pressure for 3 hours, the γ-Al₂O₃ was removed and dried under vacuum at 80 °C to prepare a porous adsorbent material.

[0049] Performance testing The porous adsorption materials provided in Examples 1-9 and Comparative Examples 1-2 of this application were subjected to the following performance tests, and the specific test results are shown in Table 1.

[0050] Detection methods I. Adsorption capacity and adsorption retention rate The porous adsorbent material prepared in this application was loaded into a fixed-bed reactor with a loading amount of 50g to test the adsorption-regeneration performance of multi-impurity propane gas.

[0051] The gas composition is: propane gas containing 100 ppm hydrogen sulfide, 50 ppm hydrogen chloride, 50 ppm thiophene, and water vapor (dew point -10℃); under conditions of 25℃ and 0.5 MPa, at a pressure of 3000 h⁻¹ -1 A volume hourly space velocity (VHSV) and a corresponding gas flow rate of 3.125 L / min were introduced into the reactor. The breakthrough time (t) was recorded when the thiophene outlet concentration was ≥1 ppm. p After adsorption saturation, switch to nitrogen gas at a space velocity of 1000 h⁻¹. -1 After regeneration at 200℃ for 8 hours and 3 cycles, the adsorption capacity q is calculated. s ; The calculation formula is: q s =C0×106×Q×t p ×M×P std / (P×T std (×22.4×m)=0.053×t p Where C0 = 50 ppm, Q = 3.125 L / min, M = 84.14 g / mol, m = 50 g, P std =1 atm, T std =273K, P=0.5MPa=5atm, T=25℃=298K and regeneration retention rate; Regeneration retention rate (%): The ratio of adsorption capacity after the third regeneration to the initial adsorption capacity.

[0052] Table 1: Performance Test Results Data Table

[0053] The performance test results show that the porous adsorbent material prepared in this application has a good adsorption capacity. A comparison between Comparative Examples 1-2 and Example 1 reveals that Comparative Example 1 does not modify the α-Al₂O₃ surface, and Comparative Example 2 uses an equal amount of γ-Al₂O₃ instead of α-Al₂O₃. The performance test results show that the adsorption capacity and adsorption stability of the prepared adsorbent material both decrease. This further demonstrates that the use of the α-Al₂O₃ crystal form and the modification of α-Al₂O₃ with an active liquid in this application significantly improve the adsorption capacity of the adsorbent material.

[0054] As can be seen from Examples 7-9, by pre-modifying α-Al2O3 with niobium pentachloride, the performance test results show that the surface acidity and adsorption sites of α-Al2O3 can be further enhanced, the surface interaction force of the adsorbent material can be strengthened, and the adsorption effect of the adsorbent material can be further improved.

[0055] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A porous adsorbent material, characterized in that, The mixture includes α-Al2O3, the surface of which is modified with an active liquid, wherein the active liquid is one of p-aminobenzenesulfonic acid solution, p-aminotoluene solution, or p-aminophenylacetic acid solution, and the mass ratio of α-Al2O3 to the active liquid is 1:(3-8); the α-Al2O3 is pre-modified with niobium pentachloride, which includes the following specific steps: mixing water, niobium pentachloride and α-Al2O3, stirring evenly and filtering, heating and drying to obtain modified α-Al2O3.

2. The porous adsorbent material according to claim 1, characterized in that, The particle size of the α-Al2O3 is 10-30 μm.

3. The porous adsorbent material according to claim 2, characterized in that, The preparation method of α-Al2O3 includes the following specific steps: Boehmite powder was mixed with water to form a suspension. The pH of the suspension was adjusted, and the suspension was heated in a water bath to obtain a sol. The sol was spray-dried into powder, and finally calcined at high temperature to obtain α-Al2O3.

4. The porous adsorbent material according to claim 3, characterized in that, Adjust the pH of the suspension to 3-4 using nitric acid.

5. The porous adsorbent material according to claim 3, characterized in that, The solid content of the suspension is 20-30%.

6. The porous adsorbent material according to claim 3, characterized in that, The calcination temperature is 1100-1200℃.

7. The porous adsorbent material according to claim 1, characterized in that, The mass ratio of niobium pentachloride to α-Al₂O₃ is (0.8-1.2):

3.

8. A method for preparing a porous adsorbent material according to any one of claims 1-7, characterized in that, The specific steps include: immersing α-Al2O3 in an active liquid, removing the α-Al2O3 after immersion at room temperature and pressure, and drying it to obtain a porous adsorbent material.

9. The method for preparing porous adsorbent material according to claim 8, characterized in that, Soaking time is 2-4 hours, then drying under vacuum at 80-90℃.

Images