Metal organic framework material as well as preparation method and application thereof
By using a mixed ligand of terephthalic acid and 1,4-naphthalenedicarboxylic acid and sodium carbonate decahydrate to prepare a metal-organic framework material, the problems of low yield and high cost in the existing technology were solved, and efficient adsorption of low-concentration benzene series and alkane mixtures was achieved, with the adsorption performance improved by 67%.
Patent Information
- Application Number
- CN202510796391.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-16
- Publication Date
- 2025-09-16
AI Technical Summary
The preparation yield of existing Al-1,4-NDC materials is low, the cost is high, and the adsorption performance for low-concentration volatile organic compounds is poor. In particular, there is competition in the adsorption of benzene series and alkane mixtures, and simultaneous adsorption cannot be achieved.
A mixture of terephthalic acid and 1,4-naphthalenedicarboxylic acid was used as a ligand, and sodium carbonate decahydrate was used as a deprotonating agent. Metal-organic framework materials were prepared through hydrothermal reaction and secondary calcination. The reaction conditions were optimized to improve the yield and adsorption performance.
The yield and adsorption performance of the material were significantly improved, the production cost was reduced, and efficient adsorption of low-concentration benzene series and alkane mixtures was achieved, with the adsorption performance increased by more than 67%.
Smart Images
Figure CN120647966A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of gas adsorption treatment, and in particular relates to a metal organic framework material, a preparation method and an application thereof. Background Art
[0002] Al-1,4-NDC is a gas adsorbent material typically prepared by mixing deionized water, an aluminum source, and an organic ligand to form a mixed solution, wherein the organic ligand is 1,4-naphthalenedicarboxylic acid. The mixed solution is reacted at 120-150°C under autogenous pressure for 24-72 hours, and the solid product is collected, dried, and calcined. This preparation method results in low product yields and high production costs due to the use of a single 1,4-naphthalenedicarboxylic acid organic ligand. Furthermore, the adsorbent exhibits poor adsorption performance for low-concentration volatile organic compounds and mixtures of benzene series and alkanes, exhibiting significant competitive adsorption, making simultaneous adsorption of the mixture impossible. Summary of the Invention
[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a metal organic framework material, a preparation method and an application thereof.
[0004] To achieve the above object, the technical solution adopted by the present invention is:
[0005] A metal organic framework material comprises an aluminum source, a ligand, and a deprotonating agent; the ligand is a mixture of terephthalic acid and 1,4-naphthalene dicarboxylic acid.
[0006] The molar ratio of 1,4-naphthalene dicarboxylic acid to terephthalic acid is (1-6): (4-9), preferably (2-6): (4-8); more preferably 4:6.
[0007] The aluminum source is aluminum chloride hexahydrate.
[0008] The deprotonating agent is sodium carbonate decahydrate.
[0009] The molar ratio of the aluminum source, the ligand, and the deprotonating agent is: (1-5): (1-5): (1-5); preferably 1:1:1.
[0010] The present invention also includes a method for preparing the metal-organic framework material, which is characterized in that it includes the following steps: first, dissolving the aluminum source and the ligand in deionized water, stirring until completely mixed, adding a deprotonating agent, transferring the solution to a hydrothermal kettle, and performing a hydrothermal reaction. The obtained product is centrifuged and washed with deionized water and then dried. After drying, the product is subjected to secondary roasting to obtain the final product; the ratio of the added amount of deionized water to the aluminum source is (150-200):1; preferably 166.5:1.
[0011] The hydrothermal reaction is carried out at 140°C-180°C for 48-64 hours; preferably at 150°C for 72 hours.
[0012] The secondary calcination conditions are calcination at 270° C.-390° C. for 6-24 hours, preferably calcination at 330° C. for 12 hours; and a heating rate of 5° C. / min.
[0013] The present invention also includes an application of the metal organic framework material, which is applied to adsorb low-concentration benzene series and alkane mixtures in a humid environment.
[0014] Compared with the prior art, the present invention has the following beneficial effects:
[0015] The technical solution of the present application uses an inorganic, non-toxic, and low-cost deprotonating agent, which can increase the solubility of terephthalic acid and 1,4-naphthalenedicarboxylic acid in water, thereby increasing the yield of the material. Compared with the preparation process without using a deprotonating agent, the yield of Al-1,4-NDC-A is increased by more than 50%; at the same time, a mixture of terephthalic acid and 1,4-naphthalenedicarboxylic acid organic ligand is used, and compared with the preparation process using a single 1,4-naphthalenedicarboxylic acid ligand, the material cost is reduced by more than 25%. The Al-1,4-NDC material prepared by this method has a high porosity and a multi-level pore structure, and can achieve efficient adsorption and removal of low-concentration benzene series and alkane mixtures. Compared with the adsorbent prepared using a single 1,4-naphthalenedicarboxylic acid ligand, the adsorption performance is improved by more than 67%. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 1 is a schematic diagram comparing XRD patterns of Al-1,4-NDC crystals obtained by the preparation methods of Examples 1 and 5 of the present invention;
[0017] Figure 2 This is a nitrogen adsorption curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5;
[0018] Figure 3 The benzene adsorption capacity curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5 under indoor dry environment;
[0019] Figure 4 This is the benzene adsorption capacity curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5 under indoor humid environment. DETAILED DESCRIPTION
[0020] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and the best embodiments.
[0021] Example 1: Preparation of a Metal-Organic Framework (MOF) Material Using the Following Steps: 2.41 g (10 mmol) of aluminum chloride hexahydrate and 2.16 g (10 mmol) of 1,4-naphthalenedicarboxylic acid) were dissolved in 30 mL of deionized water. After stirring for 0.5 hours, the mixture was transferred to a 100 mL stainless steel reactor lined with polytetrafluoroethylene and reacted at 150°C for 72 hours. After completion of the reaction, the mixture was cooled to 25°C. The product was washed three times with deionized water by centrifugation. The resulting solid was dried at 100°C for 12 hours and calcined in a muffle furnace at 330°C for 12 hours at a heating rate of 5°C / min. Al-1,4-NDC-1 was obtained with a yield of 64%. Its dynamic adsorption capacity for a low-concentration toluene / n-heptane mixture is shown in Table 1.
[0022] Example 2: Al-1,4-NDC material was prepared according to the method of Example 1, except that a mixed organic ligand of 0.22 g of 1,4-naphthalenedicarboxylic acid and 1.49 g of terephthalic acid (1,4-naphthalenedicarboxylic acid:terephthalic acid molar ratio of 1:9, total ligand amount of 10 mmol) was used. After stirring for 0.5 hour, 2.86 g (10 mmol) of sodium carbonate decahydrate was added, and stirring was continued until all bubbles disappeared. Al-1,4-NDC-2 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0023] Example 3: Al-1,4-NDC material was prepared according to the method of Example 2, except that a mixed organic ligand of 0.43 g of 1,4-naphthalenedicarboxylic acid and 1.33 g of terephthalic acid was used (the molar ratio of 1,4-naphthalenedicarboxylic acid to terephthalic acid was 2:8, and the total amount of ligands was 10 mmol). Al-1,4-NDC-3 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0024] Example 4: Al-1,4-NDC material was prepared according to the method of Example 2, except that a mixed organic ligand of 0.65 g of 1,4-naphthalenedicarboxylic acid and 1.16 g of terephthalic acid was used (the molar ratio of 1,4-naphthalenedicarboxylic acid to terephthalic acid was 3:7, and the total amount of ligands was 10 mmol). Al-1,4-NDC-4 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0025] Example 5:
[0026] Al-1,4-NDC material was prepared according to the method of Example 2, except that a mixed organic ligand consisting of 0.86 g of 1,4-naphthalenedicarboxylic acid and 1.00 g of terephthalic acid was used (the molar ratio of 1,4-naphthalenedicarboxylic acid to terephthalic acid was 4:6, and the total amount of ligands was 10 mmol). Al-1,4-NDC-5 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0027] Example 6: Al-1,4-NDC material was prepared according to the method of Example 2, except that a mixed organic ligand consisting of 1.08 g of 1,4-naphthalenedicarboxylic acid and 0.83 g of terephthalic acid was used (the molar ratio of 1,4-naphthalenedicarboxylic acid to terephthalic acid was 5:5, and the total amount of ligands was 10 mmol). Al-1,4-NDC-6 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0028] Example 7: Al-1,4-NDC material was prepared according to the method of Example 2, except that a mixed organic ligand consisting of 1.30 g of 1,4-naphthalenedicarboxylic acid and 0.66 g of terephthalic acid was used (the molar ratio of 1,4-naphthalenedicarboxylic acid to terephthalic acid was 6:4, and the total amount of ligands was 10 mmol). Al-1,4-NDC-7 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0029] Example 8: Al-1,4-NDC material was prepared according to the method of Example 5, except that the secondary calcination was carried out in a muffle furnace at 270°C for 12 hours at a heating rate of 5°C / min. Al-1,4-NDC-8 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0030] Example 9: Al-1,4-NDC material was prepared according to the method of Example 5, except that the secondary calcination was carried out in a muffle furnace at 390°C for 12 hours at a heating rate of 5°C / min. Al-1,4-NDC-9 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0031] Example 10: Al-1,4-NDC material was prepared according to the method of Example 2, except that 2.16 g of 1,4-naphthalenedicarboxylic acid was used as the ligand. Al-1,4-NDC-10 material was obtained with a yield of 96%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0032] Example 11: Al-1,4-NDC material was prepared according to the method of Example 2, except that 1.66 g of 1,4-benzenedicarboxylic acid was used as the ligand. Al-1,4-NDC-11 material was obtained with a yield of 67%. Its dynamic adsorption capacity for trace amounts of benzene is shown in Table 1.
[0033] For the tests of Examples 1-11, the trace toluene / n-heptane mixture was a mixture of 10 ppm toluene + 10 ppm n-heptane in air at a relative humidity of 20% under dry conditions and 60% under wet conditions.
[0034] Table 1
[0035]
[0036] Figure 1 1 is a schematic diagram comparing XRD patterns of Al-1,4-NDC crystals obtained by the preparation methods of Examples 1 and 5 of the present invention; Figure 2 This is a nitrogen adsorption curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5; Figure 3 The benzene adsorption capacity curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5 under indoor dry environment; Figure 4 This is the benzene adsorption capacity curve of Al-1,4-NDC obtained by the preparation method of Examples 1 and 5 under indoor humid environment.
[0037] The results show that the addition of the low-cost deprotonating agent sodium carbonate can greatly increase the yield of Al-1,4-NDC. Compared with the preparation process without using a deprotonating agent, the yield of Al-1,4-NDC-A increased by more than 50%; the use of mixed organic ligands of terephthalic acid and 1,4-naphthalenedicarboxylic acid reduced the material cost by more than 25% compared with the preparation process using a single 1,4-naphthalenedicarboxylic acid ligand, and the adsorbent can achieve efficient adsorption and removal of low-concentration benzene series and alkane mixtures. Compared with the adsorbent prepared using a single 1,4-naphthalenedicarboxylic acid ligand, the adsorption performance increased by more than 67%; compared with the adsorbent prepared using a single terephthalic acid ligand, the adsorption performance increased by more than 36%. The mixed organic ligands can increase the structural defects inside the adsorbent, increase the specific surface area of the adsorbent, and form adsorption sites with different properties, which facilitates the simultaneous adsorption of two volatile organic compounds with different properties.
[0038] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.
Claims
1. A metal organic framework material, characterized in that The method comprises an aluminum source, a ligand, and a deprotonating agent; the ligand is a mixture of terephthalic acid and 1,4-naphthalene dicarboxylic acid.
2. The metal organic framework material according to claim 1, characterized in that The molar ratio of 1,4-naphthalene dicarboxylic acid to terephthalic acid is (1-6): (4-9); preferably (2-6): (4-8); more preferably 4:
6.
3. The metal organic framework material according to claim 1, characterized in that The aluminum source is aluminum chloride hexahydrate.
4. The metal organic framework material according to claim 1, characterized in that The deprotonating agent is sodium carbonate decahydrate.
5. The metal organic framework material according to claim 1, characterized in that The molar ratio of the aluminum source, the ligand, and the deprotonating agent is: (1-5): (1-5): (1-5); preferably 1:1:
1.
6. A method for preparing the metal organic framework material according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: firstly, dissolving an aluminum source and a ligand in deionized water, stirring until completely mixed, adding a deprotonating agent, transferring the solution to a hydrothermal kettle, performing a hydrothermal reaction, washing the obtained product with deionized water by centrifugation, and drying the obtained product, and performing secondary roasting on the dried product to obtain the final product; the ratio of the added amount of deionized water to the aluminum source is (150-200):1, preferably 166.5:
1.
7. The method for preparing a metal organic framework material according to claim 6, characterized in that: The hydrothermal reaction is carried out at 140°C-180°C for 48-64 hours; preferably at 150°C for 72 hours.
8. The method for preparing a metal organic framework material according to claim 6, characterized in that: The secondary calcination conditions are calcination at 270° C.-390° C. for 6-24 hours, preferably calcination at 330° C. for 12 hours; and a heating rate of 5° C. / min.
9. Use of the metal organic framework material according to any one of claims 1 to 5, characterized in that: Used in humid environments to adsorb low concentrations of benzene series and / or alkane mixtures.