Metal-organic frameworks with excellent VOC adsorption and desorption prevention properties and articles containing the same

Abstract

To provide an organometallic structure having excellent adsorption performance for volatile organic compounds (VOCs) and at the same time, having excellent outgassing prevention performance for adsorbed VOCs.SOLUTION: This invention is a zirconium-based organometallic structure (MOF) characterized by simultaneously securing adsorption performance and outgassing prevention performance for VOCs by introducing an amine group (-NH2) into the crystal structure.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a metal-organic framework that has excellent adsorption performance for volatile organic compounds (VOCs) and also has excellent performance in preventing outgassing of adsorbed VOCs, and an article including the same. [Background technology]

[0002] There is a demand for improved formaldehyde adsorption performance and improved prevention of outgassing of adsorbed formaldehyde.

[0003] However, in the case of activated carbon, which has been used to remove VOCs along with particles (dust), for example, a 25-tsubo (800m2) air cleaner can treat particles (dust) of 25 tsubo (800m2), but can only treat VOCs of about 16 tsubo (500m2), meaning that the VOC removal performance is significantly inferior to the particle (dust) removal performance. Moreover, activated carbon causes VOCs to be re-desorbed, which can lead to the re-generation of adsorbed VOCs when the filter is used for a long period of time.

[0004] Meanwhile, the following patent document proposes a technology that uses MIL-125 MOF, a titanium-based metal-organic framework, to adsorb formaldehyde in order to improve the poor VOC adsorption properties of activated carbon. However, while MIL-125 MOF has superior VOC adsorption performance compared to activated carbon, its re-desorption performance is inferior to that of activated carbon, leaving the problem of adsorbed VOCs being re-released during filter use unresolved. [Prior art documents] [Patent documents]

[0005] (Patent Document 1) Korean Patent Publication No. 2023-0033579 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide an organometallic framework that not only has excellent adsorption performance for VOCs, but also has improved performance in preventing the desorption of adsorbed VOCs. [Means for solving the problem]

[0007] As a means for solving the above problems, the present invention provides the following metal-organic frameworks (1) to (6) and articles (7) and (8).

[0008] (1) A zirconium-based metal-organic framework (MOF) containing fumaric acid as an organic linker, which has excellent adsorption and outgassing prevention properties for volatile organic compounds.

[0009] (2) The metal-organic structure according to (1), further comprising L-aspartic acid as an organic linker.

[0010] (3) The metal-organic structure according to (2), wherein the molar ratio of fumaric acid to L-aspartic acid is 9.5:0.5 to 0.1:9.9, 9:1 to 1:9, 8.5:1.5 to 1.5:8.5, 8:2 to 2:8, 7.5:2.5 to 2.5:7.5, or 7:3 to 3:7.

[0011] (4) In any one of (1) to (3), the metal-organic structure has a crystalline structure, and the size of the entrance of a pore formed by the crystalline structure is larger than the size of the inside of the pore.

[0012] (5) The metal-organic structure according to (4), wherein an amine group (NH2) is located inside the pores.

[0013] (6) The metal-organic structure according to any one of (1) to (5), wherein the metal-organic structure has a VOC adsorption rate of 95% or more and a VOC desorption rate of 2.5% or less.

[0014] (7) An article containing any one of the metal-organic frameworks (1) to (6).

[0015] (8) In (7), the article includes a filter. [Effects of the Invention]

[0016] The metal-organic framework of the present invention not only has improved VOC adsorption performance but also improved desorption prevention performance of adsorbed VOCs compared to conventional metal-organic frameworks. [Brief explanation of the drawings]

[0017] [Figure 1] 1 shows images of organometallic frameworks synthesized in Examples 1 to 10 and Comparative Example 2 of the present invention.

[0018] [Figure 2] 1 shows the results of PXRD analysis of the organometallic structures synthesized in Examples 1 to 10 and Comparative Example 2 of the present invention.

[0019] [Figure 3] 1 shows the results of an analysis of formaldehyde adsorption and desorption prevention performance of test specimens fabricated by roll-to-roll coating using powders of metal-organic frameworks synthesized in Example 6 and Comparative Example 1 (MIL-125) of the present invention.

[0020] [Figure 4] 1 shows the results of evaluation of formaldehyde adsorption and desorption prevention performance of organometallic frameworks according to Examples 1 to 10 and Comparative Example 2.

[0021] [Figure 5] 1 shows images of organometallic frameworks synthesized in Examples 11 to 14 of the present invention.

[0022] [Figure 6] 1 shows the results of PXRD analysis of the organometallic structures synthesized in Examples 11 to 14 of the present invention.

[0023] [Figure 7] 1 shows the results of an analysis of formaldehyde adsorption and desorption prevention performance of a test piece fabricated by roll-to-roll coating the metal-organic framework powders synthesized in Examples 11 to 14 of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0025] However, the following examples of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the following detailed examples. The examples of the present invention are provided to more completely explain the present invention to those skilled in the art.

[0026] Example 1

[0027] The metal-organic framework according to Example 1 was synthesized using the raw materials shown in Table 1 below in the following process.

[0028] [Table 1]

[0029] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0030] Then, 12.19 g (0.21 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 1 (InCube 206 (0:10)). After synthesis, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was dried in a vacuum oven at 110°C to obtain a white powder metal-organic framework. Since the formic acid used in Table 1 was used as a solvent, it was not substantially present in the resulting metal-organic framework. However, a small amount of formic acid may remain as an impurity during the synthesis process. This also applies to the metal-organic frameworks obtained in Examples 2 to 14 below.

[0031] <Example 2>

[0032] The metal-organic framework of Example 2 was synthesized using the raw materials shown in Table 2 below in the following process.

[0033] [Table 2]

[0034] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0035] Next, 2.80 g (0.021 mol) of L-aspartic acid was added and completely dissolved. Finally, 21.94 g (0.189 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 2 (InCube 206 (1:9)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0036] Example 3

[0037] The metal-organic framework according to Example 3 was synthesized using the raw materials shown in Table 3 below in the following process.

[0038] [Table 3]

[0039] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0040] Next, 5.59 g (0.042 mol) of L-aspartic acid was added and completely dissolved. Finally, 19.5 g (0.168 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 3 (InCube 206 (2:8)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0041] Example 4

[0042] The metal-organic framework of Example 4 was synthesized using the raw materials in Table 4 below according to the following process.

[0043] [Table 4]

[0044] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0045] Next, 8.39 g (0.063 mol) of L-aspartic acid was added and completely dissolved. Finally, 17.06 g (0.147 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 4 (InCube 206 (3:7)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0046] <Example 5>

[0047] The metal-organic framework according to Example 5 was synthesized using the raw materials listed in Table 5 below in the following process.

[0048] [Table 5]

[0049] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0050] Next, 11.18 g (0.084 mol) of L-aspartic acid was added and completely dissolved. Finally, 14.63 g (0.126 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 5 (InCube 206 (4:6)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0051] Example 6

[0052] The metal-organic framework of Example 6 was synthesized using the raw materials in Table 6 below according to the following process.

[0053] [Table 6]

[0054] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0055] Next, 13.98 g (0.105 mol) of L-aspartic acid was added and completely dissolved. Finally, 12.19 g (0.105 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 6 (InCube 206 (5:5)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0056] Example 7

[0057] The metal-organic framework of Example 7 was synthesized using the raw materials in Table 7 below according to the following process.

[0058] [Table 7]

[0059] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0060] Next, 16.77 g (0.126 mol) of L-aspartic acid was added and completely dissolved. Finally, 9.75 g (0.084 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 7 (InCube 206 (6:4)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0061] Example 8

[0062] The metal-organic framework of Example 8 was synthesized using the raw materials in Table 8 below according to the following process.

[0063] [Table 8]

[0064] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0065] Next, 19.57 g (0.147 mol) of L-aspartic acid was added and completely dissolved. Finally, 7.31 g (0.063 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 8 (InCube 206 (7:3)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0066] <Example 9>

[0067] The metal-organic framework of Example 9 was synthesized using the raw materials in Table 9 below according to the following process.

[0068] [Table 9]

[0069] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0070] Next, 22.36 g (0.168 mol) of L-aspartic acid was added and completely dissolved. Finally, 4.87 g (0.042 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 9 (InCube 206 (8:2)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0071] Example 10

[0072] The metal-organic framework of Example 10 was synthesized using the raw materials in Table 10 below according to the following process.

[0073] [Table 10]

[0074] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0075] Next, 25.16 g (0.189 mol) of L-aspartic acid was added and completely dissolved. Finally, 2.44 g (0.021 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 10 (InCube 206 (9:1)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0076] Example 11

[0077] The metal-organic framework of Example 11 was synthesized using the raw materials in Table 11 below according to the following process.

[0078] [Table 11]

[0079] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0080] Next, 26.55 g (0.1995 mol) of L-aspartic acid was added and completely dissolved. Finally, 1.22 g (0.0105 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 11 (InCube 206 (0.5:9.5)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0081] Example 12

[0082] The metal-organic framework of Example 12 was synthesized using the raw materials in Table 12 below according to the following process.

[0083] [Table 12]

[0084] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0085] Next, 26.83 g (0.2016 mol) of L-aspartic acid was added and completely dissolved. Finally, 0.97 g (0.0084 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 12 (InCube 206 (0.4:9.6)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0086] Example 13

[0087] The metal-organic framework of Example 13 was synthesized using the raw materials in Table 13 below according to the following process.

[0088] [Table 13]

[0089] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0090] Next, 27.11 g (0.2037 mol) of L-aspartic acid was added and completely dissolved. Finally, 0.73 g (0.0063 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 13 (InCube 206 (0.3:9.7)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0091] Example 14

[0092] The metal-organic framework of Example 14 was synthesized using the raw materials in Table 14 below according to the following process.

[0093] [Table 14]

[0094] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0095] Next, 27.67 g (0.2079 mol) of L-aspartic acid was added and completely dissolved. Finally, 0.24 g (0.0021 mol) of fumaric acid was added and stirred. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Example 14 (InCube 206 (0.1:9.9)). After synthesis was complete, the mixture was filtered through a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder of the metal-organic framework.

[0096] Example 15

[0097] To measure the formaldehyde absorption / desorption properties of the metal-organic frameworks according to Examples 1 to 14, suspensions were prepared using the metal-organic frameworks according to Examples 1 to 14, which were then subjected to roll-to-roll coating as known in the art and dried. At this time, the amount of sample loaded onto the coated sheet was 1 m of the sheet. 2 Each serving weighs 30 to 100g.

[0098] <Comparative Example 1>

[0099] For comparison with Examples 1 to 10, MIL125 MOF was synthesized by the following process.

[0100] 0.5g (0.003mol) of terephthalic acid was added to DMF / MeOH (9 / 1mL) and completely dissolved. 0.26ml (0.0008mol) of titanium butoxide was added to the solution and stirred. The solution was then transferred to a 20mL Teflon container, placed in an autoclave, and heated at 150°C for 24 hours. After synthesis was complete, the mixture was filtered using a centrifuge and washed three times with DMF and MeOH. After washing, the mixture was vacuum dried in an oven at 80°C to obtain a white powder metal-organic framework.

[0101] <Comparative Example 2>

[0102] The metal-organic framework of Comparative Example 2 was synthesized using the raw materials in Table 15 below according to the following process.

[0103] [Table 15]

[0104] Add 32.23g (0.1mol) of Zirconium(IV) oxychloride to 100ml of distilled water and dissolve it completely. Add 92.06g of formic acid to the solution and stir.

[0105] Then, 27.95 g (0.21 mol) of L-aspartic acid was added and completely dissolved. The final solution was refluxed at 120°C for 24 hours to synthesize the metal-organic framework of Comparative Example 2 (InCube 206 (0:10)). After synthesis was complete, the mixture was filtered using a Buchner filter and washed with water and ethanol. After washing, the mixture was vacuum dried in an oven at 110°C to obtain a white powder metal-organic framework.

[0106] <Comparative Example 3>

[0107] In a method for preparing a sample for measuring the formaldehyde absorption / desorption properties of the organometallic frameworks according to Comparative Examples 1 and 2, a suspension was prepared using the organometallic framework according to Comparative Example 1, which was then subjected to a known roll-to-roll coating and dried. At this time, the amount of sample loaded onto the coated sheet was 1 m of the sheet. 2 Each serving weighs 30 to 50g.

[0108] Figure 1 shows images of the organometallic frameworks synthesized in Examples 1 to 10 of the present invention and Comparative Example 2. As can be seen from Figure 1, the organometallic frameworks synthesized in Examples 1 to 10 and Comparative Example 2 were formed in the form of particles with sizes ranging from about several nm to several hundred nm.

[0109] Figure 2 shows the PXRD analysis results of the organometallic structures synthesized in Examples 1 to 10 of the present invention and Comparative Example 2. As can be seen from Figure 2, the organometallic structures synthesized in Examples 1 to 10 and Comparative Example 2 were confirmed to be crystalline through PXRD analysis.

[0110] Figure 3 shows the results of an analysis of the formaldehyde adsorption and desorption prevention performance of test specimens fabricated by roll-to-roll coating using powders of metal-organic frameworks synthesized in Example 6 of the present invention and Comparative Example 1 (MIL-125, indicated as "current material" in the drawing). As can be seen from Figure 3, the formaldehyde adsorption and desorption prevention performance of the sample of Example 6 is superior to that of the current sample.

[0111] Formaldehyde adsorption and desorption performance was evaluated in ppm units using a circulation-type adsorption measurement system. Formaldehyde gas of a specific concentration was produced in a chamber within the measurement system, and the gas was passed through a roll-to-roll coated test piece to track the concentration change within the chamber, leading to the desorption and adsorption isotherms of formaldehyde. To measure adsorption performance, approximately 20 ppm or less of formaldehyde gas was passed through the test piece, and the amount of formaldehyde adsorbed was measured for 20 minutes. After adsorption, formaldehyde-free gas was introduced, and the amount of formaldehyde generated from the test piece was measured for 20 minutes, to measure the amount of formaldehyde re-desorbed from the test piece.

[0112] FIG. 4 shows the evaluation results of formaldehyde adsorption and desorption prevention performance of the organometallic frameworks according to Examples 1 to 10 and Comparative Example 2.

[0113] As can be seen from FIG. 4, Examples 2 to 10 have superior formaldehyde adsorption and desorption prevention performance compared to the current material in Comparative Example 1, and in particular, Examples 4 to 8 have significantly improved adsorption and desorption prevention performance compared to the current material.

[0114] FIG. 5 shows images of the organometallic frameworks synthesized in Examples 11 to 14 of the present invention.

[0115] As can be seen from FIG. 5, the organometallic frameworks synthesized in Examples 11 to 14 were formed in the form of particles with sizes ranging from about several nm to several hundred nm.

[0116] FIG. 6 shows the PXRD analysis results of the organometallic structures synthesized in Examples 11 to 14 of the present invention.

[0117] As can be seen from FIG. 6, the organometallic frameworks synthesized in Examples 11 to 14 were confirmed to be crystalline through PXRD analysis.

[0118] FIG. 7 shows the evaluation results of formaldehyde adsorption and desorption prevention performance of the organometallic frameworks according to Examples 11 to 14.

[0119] As can be seen from FIG. 7, Examples 11 to 14 have excellent formaldehyde adsorption and desorption prevention performance compared to the current material of Comparative Example 1.

[0120] Table 16 is a numerical representation of the results of FIGS. 4 and 7, and summarizes the amount and rate of formaldehyde adsorption, and the amount and rate of formaldehyde desorption.

[0121] [Table 16]

[0122] As can be seen from Table 16, Examples 1 to 14 of the present invention not only have a higher formaldehyde adsorption amount but also a lower formaldehyde desorption rate compared to MIL-125, which was developed to improve the adsorption performance of existing VOCs.

[0123] On the other hand, in the case of Comparative Example 2, which does not contain fumaric acid, the adsorption amount of formaldehyde was improved compared to MIL-125, but the desorption rate of formaldehyde was also higher.

[0124] Among the examples of the present invention, in particular, Example 4 (InCube206-(7:3)) to Example 8 (InCube206-(3:7)) have a high formaldehyde adsorption rate and a low formaldehyde desorption rate, and therefore exhibit more preferable performance.

Claims

1. A zirconium-based metal-organic framework (MOF) containing fumaric acid and L-aspartic acid as organic linkers, which has excellent adsorption performance and outgassing prevention performance for volatile organic compounds.

2. 2. The metal-organic structure according to claim 1, wherein the mixing ratio of said fumaric acid to said L-aspartic acid is 9.5:0.5 to 0.1:9.9 in terms of molar ratio.

3. 2. The metal-organic structure according to claim 1, wherein the mixing ratio of said fumaric acid and L-aspartic acid is 9:1 to 1:9 in terms of molar ratio.

4. 2. The metal-organic structure according to claim 1, wherein the molar ratio of fumaric acid to L-aspartic acid is 7.5:2.5 to 2.5:7.

5.

5. The metal-organic framework has a crystalline structure, The pores formed by the crystal structure contain amine groups (NH ２ 2. The metal-organic structure of claim 1 , wherein

6. 5. The metal-organic structure according to claim 1, wherein the metal-organic structure has a VOC adsorption rate of 95% or more and a VOC desorption rate of 2.5% or less.

7. An article comprising the metal-organic framework of any one of claims 1 to 4.

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