Organic compound adsorbent and gas blower containing same

Abstract

The present invention relates to a metal-organic framework having a BET specific surface area of ​​500 m 2 / g or more, and the relationship between the average diameter inside the unit pores of the metal organic framework and the average diameter inside the unit pores satisfies Mathematical Formula 1, thereby making it possible to improve the adsorption amount and adsorption speed of volatile organic compounds even in a dynamic gas flow with a flow rate of 1 cm / sec or more. This relates to an organic compound adsorbent and a gas blower including the same that can efficiently adsorb volatile organic compounds in a gas flow environment such as an air purifier or air conditioner.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0114705, filed August 30, 2021, and Korean Patent Application No. 10-2022-0091911, filed July 25, 2022, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an organic compound adsorbent and a gas blower including the same, and more particularly to an organic compound adsorbent that can improve the adsorption amount and adsorption speed of volatile organic compounds under dynamic gas flow conditions, and a gas blower including the same. [Background technology]

[0003] Air contains fine dust (PM10), ultrafine dust (PM2.5), harmful gases, bacteria, mold, viruses, and other substances that can cause illness and have a negative impact on health.Volatile organic compounds (VOCs), in particular, are air pollutants and carcinogenic toxic chemicals that are extremely harmful to the human body.

[0004] To reduce such volatile organic compounds, organic compound adsorbents containing activated carbon have been used in air purifiers, air purification filters, air conditioners, etc. However, while these adsorbents are highly effective in removing toluene, which is a volatile organic compound, they have a problem in that they are weak in removing formaldehyde and ammonia.

[0005] In recent years, it has been reported that MOFs (Metal Organic Frameworks), which are porous metal-organic frameworks, can improve the ability to remove volatile organic compounds such as formaldehyde and ammonia. However, there is a problem in that their ability to remove volatile organic compounds decreases under conditions of dynamic gas flow, such as in air purifiers or air conditioners. This is because even if the same MOF is used, each MOF has different unit pore opening sizes, unit pore internal sizes, and pore shapes, which can lead to differences in the amount of volatile organic compounds adsorbed inside the pores, and this difference is greater under conditions of dynamic gas flow than under conditions of static gas flow. Therefore, there is a need for research into metal-organic framework structures that can adsorb large amounts of volatile organic compounds in a short period of time even under dynamic gas flow conditions. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made to solve the above-mentioned problems, and focuses on the relationship between the structure of a metal organic framework and the adsorption capacity of volatile organic compounds. The present invention aims to provide an organic compound adsorbent and a gas blower including the same, which can improve the adsorption amount and adsorption speed of volatile organic compounds adsorbed inside pores under dynamic gas flow conditions by optimizing the BET specific surface area of the metal organic framework, the average diameter range of the unit pore entrance, and the average diameter range of the unit pore interior. [Means for solving the problem]

[0007] The present invention provides an organic compound adsorbent and a gas blower. (1) The present invention is a polymeric nanotube having a variable pore structure formed by the bonding structure of metal ions and organic ligands, and a BET specific surface area of 500 m 2 / g or more and satisfying the following mathematical formula 1 under a gas flow with a flow rate of 1 cm / sec or more; and a carbon-based support on which the metal organic framework is supported.

[0008] [Mathematical formula 1] 0.4≦x(nm) / y(nm)≦1.0

[0009] In the above mathematical formula 1, x is the average diameter (nm) of the entrance of a unit pore of the metal organic framework measured by one or more methods of X-ray diffraction, gas adsorption, and mercury porosimeter; y is the average diameter (nm) of the unit pores of the metal organic framework measured by one or more of X-ray diffraction, gas adsorption, and mercury porosimeter.

[0010] (2) The present invention provides the adsorbent for organic compounds according to (1) above, wherein x is 0.2 nm or more and 1.4 nm or less, and y is 0.5 nm or more and 2.2 nm or less.

[0011] (3) The present invention provides the adsorbent for organic compounds according to (1) or (2) above, wherein x is 0.35 nm or more and 1.2 nm or less, and y is 0.7 nm or more and 2.0 nm or less.

[0012] (4) In the present invention, there is provided the organic compound adsorbent according to any one of (1) to (3), wherein the metal organic framework has a removal rate constant value of 0.03 or more, as calculated by the following mathematical formula 2:

[0013] [Mathematical formula 2] C t =C i ×e -kt

[0014] In the above mathematical formula 2, C t is the concentration of formaldehyde after t minutes, C iis the initial formaldehyde concentration, K is the removal rate constant, T means elapsed time (min).

[0015] (5) In the present invention, the BET specific surface area of the metal organic framework is 800 m 2 The adsorbent for organic compounds according to any one of (1) to (4) above has a specific surface area of 1000 nm or more.

[0016] (6) The present invention provides the adsorbent for organic compounds according to any one of (1) to (5), wherein the metal ions are ions of one or more metals selected from the group consisting of sodium (Na), potassium (K), rubidium (Rb), calcium (Ca), strontium (Sr), barium (Ba), scandium (Sc), yttrium (Y), hafnium (Hf), niobium (Nb), chromium (Cr), silver (Ag), indium (In), germanium (Ge), tin (Sn), aluminum (Al), iron (Fe), molybdenum (Mo), tungsten (W), vanadium (V), zinc (Zn), zirconium (Zr), copper (Cu), magnesium (Mg), manganese (Mn), nickel (Ni), titanium (Ti), and lanthanum transition metals.

[0017] (7) The present invention provides the adsorbent for organic compounds according to any one of (1) to (6) above, wherein the organic ligand contains two or more functional groups capable of binding to the metal ions.

[0018] (8) The present invention provides the adsorbent for organic compounds according to any one of (1) to (7), wherein the organic ligand is at least one selected from the group consisting of imidazole, alkylimidazole, alkoxyimidazole, terephthalic acid, aminoterephthalic acid, trimesic acid, fumaric acid, and maleic acid.

[0019] (9) The present invention provides the adsorbent for organic compounds according to any one of (1) to (8), wherein the carbon-based support comprises one or more selected from the group consisting of carbon nanotubes, graphene, graphite, amorphous carbon, carbon black, and activated carbon.

[0020] (10) The present invention provides the adsorbent for organic compounds according to any one of (1) to (9), wherein the adsorbent contains the metal-organic framework in an amount of 3 to 95 parts by weight relative to 100 parts by weight of the carbon-based support.

[0021] (11) The present invention provides a gas blower including the organic compound adsorbent according to any one of (1) to (10) above, wherein a gas flow velocity exists. [Effects of the Invention]

[0022] The present invention relates to a metal-organic framework having a BET specific surface area of 500 m 2 / g or more, and the relationship between the average diameter inside the unit pores of the metal organic framework and the average diameter inside the unit pores satisfies mathematical formula 1, the adsorption amount and adsorption speed of volatile organic compounds can be improved even in dynamic gas flows with a flow rate of 1 cm / sec or more, and volatile organic compounds can be efficiently adsorbed in environments where high gas flow rates are present, such as in air purifiers and air conditioners. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic diagram of a measuring device for evaluating the volatile organic compound removal performance of the organic compound adsorbent of the present invention. [Figure 2] 1 is a graph showing the amount of formaldehyde reduction of the organic compound adsorbent of the present invention over time, measured by the measuring device. [Figure 3] 1 shows an image of the crystal structure of the metal-organic framework of Example 1 visualized using a visualization program (Mercury). DETAILED DESCRIPTION OF THE INVENTION

[0024] The terms and words used in this specification and claims should not be interpreted in a limited way to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of the present invention, based on the principle that the inventors can appropriately define the concepts of terms in order to best explain their inventions.

[0025] In the present invention, the diameter can be defined as the length of the longest straight line connecting two different points on a circle, ellipse, or polygon that forms the cross section of a unit pore of a metal organic framework.

[0026] In the present invention, the average diameter may be defined as a diameter that accounts for 50% or more of the cumulative volume in a diameter distribution measured using one or more of X-ray diffraction, gas adsorption, and mercury porosimeter. In the present invention, the average diameter inside the unit pore may refer to the average depth inside the unit pore of the metal organic framework.

[0027] Metal-organic frameworks (MOFs) are crystalline organic-inorganic hybrid materials in which metal ions or ion clusters are linked by organic ligands that act as linkers to form networks with primary, secondary, or tertiary structures.

[0028] Such metal organic frameworks may be produced by microwave heating synthesis, which heats reactants using the interaction between electromagnetic waves and charged bodies; electrochemical synthesis, which combines a metal cation material such as Zn or Cu with a linker such as 1,3,5-H3BTC or H2BDC(OH)2 and then uses solvothermal heat; or mechanochemical synthesis, which involves breaking intramolecular bonds and then using a chemical conversion process.

[0029] In addition, since the functional groups on the surface of the metal-organic framework can be adjusted or the pore size can be finely changed, the metal-organic framework can also be used as a drug delivery system in the biomedical field. Since the metal-organic framework contains metal ions or ion groups, it can also be used as a heterogeneous catalyst in catalytic reactions, anaerobic olefin oxidation reactions, olefin epoxidation reactions, Friedel-Crafts benzylation reactions, etc.

[0030] In particular, metal-organic frameworks have a porous structure with open spaces in the framework. Due to the porous structure of such metal-organic frameworks, they have a high gas storage capacity and can reversibly adsorb or desorb gases under mild conditions, making them useful in the field of storing gases such as hydrogen, methane, and carbon dioxide, and also enabling the selective separation of specific gases from a gas mixture.

[0031] Furthermore, due to the porous structure of such metal-organic frameworks, they have adsorption properties for a variety of organic compounds, and in particular, they exhibit excellent adsorption properties for volatile organic compounds (VOCs). Volatile organic compounds are a collective term for liquid or gaseous organic compounds that easily evaporate into the atmosphere. They are air pollutants and precursors of photochemical oxidants, which are toxic chemicals with carcinogenic properties. Depending on the emission source, these compounds are either naturally emitted or artificially emitted. Compounds that are particularly problematic are compounds such as formaldehyde and ammonia. Organic compound adsorbents containing metal-organic frameworks exhibit superior adsorption properties for volatile organic compounds compared to the widely used zeolites and activated carbons.

[0032] In general, the structure of a porous metal-organic framework can have a shape in which the average diameter inside the unit pore is larger than the average diameter at the entrance of the unit pore. This allows volatile organic compound molecules that enter the pores of the metal-organic framework to be adsorbed inside the pores without being desorbed again. Furthermore, in a static gas flow environment, increasing the average diameter inside the unit pore of the metal-organic framework increases the space available for adsorbing volatile organic compounds inside the pores, thereby improving the amount of volatile organic compound adsorption.

[0033] However, in environments with dynamic gas flow, such as air purifiers and air conditioners, increasing the average diameter inside the unit pores of a metal organic framework can prevent volatile organic compounds from entering the pores due to the fast gas flow. Furthermore, increasing the average diameter of the unit pore inlet to allow volatile organic compounds to enter the pores can result in the volatile organic compounds adsorbed inside the pores being re-desorbed. Therefore, even if a metal organic framework is included in an organic compound adsorbent to adsorb volatile organic compounds, the amount or rate of adsorption of volatile organic compounds decreases under dynamic gas flow conditions, making it unsuitable for use in air purifiers or air conditioners, where dynamic gas flow conditions exist.

[0034] The inventors of the present invention have conducted extensive research to solve the problem that the amount and speed of volatile organic compounds adsorbed by metal-organic frameworks, which have been used to adsorb conventional volatile organic compounds, decrease when the frameworks are used in gas flow environments such as air purifiers and air conditioners. As a result of their research, they have discovered a metal-organic framework with a BET specific surface area of 500 m 2 / g or more, and the relationship between the average diameter inside the unit pores of the metal organic framework and the average diameter inside the unit pores satisfies specific conditions, it has been found that it is possible to improve the adsorption amount and adsorption rate of volatile organic compounds even in a dynamic gas, such as an air flow, with a flow rate of 1 cm / sec or more, and the present invention has been completed based on this finding.

[0035] The present invention is a nano-sized nano-particle that contains tunable pores formed by the bonding structure of metal ions and organic ligands, and has a BET specific surface area of 500 m 2 / g or more and satisfying the following mathematical formula 1 under a gas flow with a flow rate of 1 cm / sec or more; and a carbon-based support on which the metal organic framework is supported.

[0036] [Mathematical formula 1] 0.4≦x(nm) / y(nm)≦1.0

[0037] In Equation 1, x is the average diameter (nm) of the entrance of the unit pores of the metal organic framework measured by one or more of X-ray diffraction, gas adsorption, and mercury porosimeter, and y is the average diameter (nm) of the interior of the unit pores of the metal organic framework measured by one or more of X-ray diffraction, gas adsorption, and mercury porosimeter.

[0038] The metal-organic framework of the present invention has a variable pore due to the bonding structure between the metal ions and the organic ligands. The variable pore may mean that the diameter of the pore is not fixed but changes depending on a specific environment. Specifically, the organic ligands constituting the metal-organic framework are not fixed at room temperature and may have the characteristic of rotating along the axis bonding with the metal ions. Therefore, the shape of the metal-organic framework, the average diameter of the entrance of the unit pores of the metal-organic framework, and the average diameter inside the unit pores may change depending on the rotation of the organic ligands. In particular, when the metal-organic framework is placed under dynamic conditions in which the surrounding gas flow has a specific flow rate, the average diameter of the entrance of the unit pores and the average diameter inside the unit pores of the metal-organic framework may change.

[0039] In Formula 1, the ratio (x / y) of the average diameter at the entrance of a unit pore to the average diameter inside the unit pore of the metal organic framework may be 0.4 or more, 0.45 or more, 0.5 or more, 0.53 or more, 0.55 or more, 0.58 or more, 1.0 or less, 0.95 or less, 0.9 or less, 0.85 or less, 0.8 or less, 0.75 or less, 0.7 or less, 0.65 or less, or 0.6 or less.

[0040] In the above mathematical formula 1, when the ratio of the average diameter (nm) of the unit pore entrance to the average diameter (nm) of the unit pore interior of the metal organic framework is outside the lower limit of the above numerical range, the contact time between the metal organic framework and the volatile organic compound is shorter than the time required for the metal organic framework to adsorb the volatile organic compound contained in the gas having a flow rate, and therefore the effect of the metal organic framework in adsorbing the volatile organic compound may be significantly reduced.

[0041] In addition, when the ratio (nm) of the average diameter of the entrance of the unit pores of the metal organic framework to the average diameter (nm) of the interior of the unit pores is outside the upper limit of the above range, the volatile organic compounds adsorbed in the pores of the metal organic framework are likely to escape through the entrance of the pores of the metal organic framework, which may result in a significant increase in the rate at which the volatile organic compounds are re-desorbed from the metal organic framework. 2 / g or more, 800m 2 / g or more, 1,000m 2 / g or more, 1,500m 2 / g or more.

[0042] In addition, in Formula 1, x may be 0.2 nm or more and 1.4 nm or less, and y may be 0.5 nm or more and 2.2 nm or less. More specifically, in Formula 1, x may be 0.2 nm or more, 0.25 nm or more, 0.3 nm or more, 0.35 nm or more, 0.4 nm or more, 1.4 nm or less, 1.3 nm or less, or 1.2 nm or less. In addition, in Formula 1, y may be 0.5 nm or more, 0.6 nm or more, 0.7 nm or more, 2.2 nm or less, 2.1 nm or less, or 2.0 nm or less.

[0043] A pore diameter of the metal-organic framework that satisfies the above-mentioned range does not decrease the performance of adsorbing volatile organic compounds with large molecular weights, and by reducing the rate at which the adsorbed volatile organic compounds are re-desorbed, it is possible to improve not only the adsorption amount but also the adsorption speed of volatile organic compounds in a dynamic gas flow with a flow rate of 1 cm / sec or more.

[0044] According to one embodiment of the present invention, the adsorbent for organic compounds of the present invention may be an adsorbent for organic compounds, wherein the metal organic framework has a removal rate constant value of 0.03 or more, as calculated by the following Mathematical Equation 2:

[0045] [Mathematical formula 2] C t =C i ×e -kt

[0046] In the above mathematical formula 2, C t is the concentration of the target organic compound (μmol / mol) after t minutes have elapsed, and C i is the initial target organic compound concentration (μmol / mol), k is the removal rate constant, and t is the elapsed time (min).

[0047] The target organic compound may be formaldehyde or ammonia, and specifically may be formaldehyde. The removal rate constant k is calculated by the relationship between t and InC tThe value of the removal rate constant k is an index capable of confirming the performance of the adsorption amount and adsorption rate of the organic compound adsorbent, and when the value of the removal rate constant k is in the above-mentioned range of 0.03 or more, it is possible to achieve the optimal adsorption amount and adsorption rate for adsorbing volatile organic compounds in a dynamic gas flow.

[0048] On the other hand, the metal organic framework of the present invention is composed of a bond structure of metal ions and organic ligands, and the metal ions may be ions of one or more metals selected from the group consisting of sodium (Na), potassium (K), rubidium (Rb), calcium (Ca), strontium (Sr), barium (Ba), scandium (Sc), yttrium (Y), hafnium (Hf), niobium (Nb), chromium (Cr), silver (Ag), indium (In), germanium (Ge), tin (Sn), aluminum (Al), iron (Fe), molybdenum (Mo), tungsten (W), vanadium (V), zinc (Zn), zirconium (Zr), copper (Cu), magnesium (Mg), manganese (Mn), nickel (Ni), titanium (Ti), and lanthanum transition metals.

[0049] The organic ligand may contain two or more functional groups capable of bonding with the metal ion, and may be, for example, a compound containing a functional group containing nitrogen (N), oxygen (O), or sulfur (S). Specifically, the organic ligand may be one or more selected from the group consisting of imidazole, alkylimidazole, alkoxyimidazole, terephthalic acid, aminoterephthalic acid, trimesic acid, fumaric acid, and maleic acid.

[0050] Furthermore, the metal-organic framework of the present invention may be a MIL (Materials Institute Lavoisier)-based metal-organic framework, and preferably MIL-125(Ti) containing a titanium (Ti)-based metal.

[0051] Furthermore, the metal organic framework of the present invention may have a water adsorption amount of 40 wt% or less when measured at a relative humidity of 100% or less. Specifically, the water adsorption amount of the metal organic framework of the present invention when measured at a relative humidity of 100% or less may be 40 wt% or less, 30 wt% or less, 20 wt% or less, or 10 wt% or less.

[0052] According to one embodiment of the present invention, there is provided an organic compound adsorbent comprising the metal-organic framework supported on a support. The support may be a carbon-based support and may include one or more materials selected from the group consisting of carbon nanotubes, graphene, graphite, amorphous carbon, carbon black, and activated carbon. In addition, considering that the metal-organic nanostructure has relatively poor adsorption performance for toluene, which is one of the volatile organic compounds, it is preferable to use activated carbon, which has excellent adsorption performance for toluene.

[0053] Furthermore, the metal-organic framework may be contained in an amount of 3 to 95 parts by weight, 30 to 95 parts by weight, 50 to 90 parts by weight, or 50 to 80 parts by weight relative to 100 parts by weight of the support. By satisfying the above-mentioned ranges, there is an effect that the deodorizing property is not reduced and the phenomenon in which the metal-organic framework is desorbed by external gas can be reduced.

[0054] The metal-organic framework may be supported on a carbon-based support in the form of a powder, granules, or coating, or may be supported between carbon-based supports. The organic compound adsorbent may also be prepared by filling the metal-organic framework between nonwoven carbon-based supports. The carbon-based support may be formed in a mesh shape, and the carbon-based support may be adjusted to an appropriate mesh size as needed to prevent the metal-organic framework from escaping to the outside of the organic compound adsorbent. When the carbon-based support is formed in a mesh shape, the mesh diameter of the carbon-based support may be 160 μm or less, 150 μm or less, 140 μm or less, 130 μm or less, or 120 μm or less. The organic compound adsorbent may be a moisture absorbent or a deodorizer.

[0055] According to another embodiment of the present invention, there is provided a gas blower including the organic compound adsorbent, in which a gas flow rate exists. Specifically, the gas blower can be used without limitation in products that require an organic compound adsorbent among products in which a gas flow rate exists, and can be applied to various products such as air purifiers and air conditioners.

[0056] The present invention will be described in more detail below with reference to specific examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0057] Examples and Comparative Examples Example 1 3.0 g of terephthalic acid was dissolved in 60 ml of dimethylformamide, followed by mixing with 3 ml of anhydrous methanol and 3 ml of titanium isopropoxide. This mixture was transferred to a 200 ml Teflon container, placed in a stainless steel autoclave, and heated at 150°C for 24 hours. After cooling to room temperature, the resulting white solid was filtered and washed once with 20 ml of DMF and three times with 40 ml of methanol. It was then dried in a vacuum oven at 100°C to obtain a metal-organic framework.

[0058] Example 2 3.15g of zirconium tetrachloride and 2.45g of 2-aminoterephthalic acid were dissolved in 519ml of dimethylformamide and then heated in an oven at 120°C for 6 hours without stirring. After cooling to room temperature, the formed pale yellow solid was collected using a filter method, washed once with 100ml of DMF and three times with 100ml of methanol, and then dried in a vacuum oven at 120°C to obtain a metal organic framework.

[0059] Example 3 8.1g of fumaric acid and 23g of zirconium dichloride oxo octahydrate were dissolved in a mixed solvent of 3,500ml of dimethylformamide and 530ml of formic acid, and then heated in an oven at 120°C for 24 hours without stirring. After cooling to room temperature, the pale white solid that formed was collected using a filter method, washed once with 200ml of DMF and three times with 1000ml of methanol, and then dried in a vacuum oven at 150°C to obtain a metal-organic framework.

[0060] Comparative Example 1 3.5g of zirconium tetrachloride and 2.5g of terephthalic acid were dissolved in 155ml of dimethylformamide, followed by the addition of 1.5ml of 36% aqueous hydrochloric acid. The mixture was heated in an oven at 120°C for 24 hours without stirring. After cooling to room temperature, the white solid formed was filtered and washed once with 100ml of DMF and three times with 100ml of methanol. The solid was then dried in a vacuum oven at 120°C to obtain a metal-organic framework.

[0061] Comparative Example 2 Solution 1 was prepared by dissolving 5.94 g of zinc nitrate hexahydrate in 30 ml of distilled water, and solution 2 was prepared by mixing 3.28 g of 2-methylimidazole, 50 ml of triethylamine, and 37.6 g of saturated aqueous ammonia. Solution 1 and solution 2 were mixed and stirred at room temperature for 10 minutes, and the resulting white solid was separated by centrifugation. The white solid was washed once with 100 ml of DMF and three times with 100 ml of methanol, and then dried in a vacuum oven at 120°C to obtain a metal-organic framework.

[0062] Comparative Example 3 4.75g of magnesium nitrate hexahydrate and 11.6g of 2,6-dihydroxyterephthalic acid were dissolved in 440ml of dimethylformamide. This solution was mixed with 30ml of ethanol and 30ml of aqueous solution, and then heated in an oven at 125°C for 15 hours. After cooling to room temperature, the formed dark yellow solid was collected using a filter, washed once with 200ml of DMF and three times with 100ml of methanol, and then dried in a vacuum oven at 120°C to obtain a metal-organic framework.

[0063] Experimental example Experimental Example 1 For the metal organic frameworks of the Examples and Comparative Examples, the average diameter of the unit pore entrance and the average diameter inside the unit pore, the BET specific surface area, and the VOC removal performance were measured by the following methods, and the measurement results are shown in Table 1. In addition, after measuring the VOC removal performance, the CADR (Clean Air Delivery Rate) and removal rate constant were calculated to compare the removal performance of the Examples and Comparative Examples, and are shown in Table 1 below.

[0064] 1) Measurement of the average diameter of the entrance and interior of a unit pore: The single crystal structure file (CIF: Crystal Information File) of the metal-organic framework measured by X-ray diffraction analysis (XRD apparatus and conditions: Bruker SMART Apex Diffactometer, Mo Kα radiation, 0.71073A wavelength, 30 seconds / frame, angle 0-180°) was visualized using a visualization program (Mercury) to confirm the synthesis of each example and comparative example. Subsequently, using the single crystal structure recorded in the Cambridge Structural Database (CSD), the average diameter of the entrance of a unit pore was measured by measuring the center-to-center distance between the two most distant atoms constituting the entrance of a unit pore of the metal-organic framework. The average diameter of the interior of a unit pore was measured in the same manner as the method for measuring the average diameter of the entrance of a unit pore, except that the center-to-center distance between the two most distant atoms constituting the interior of a unit pore of the metal-organic framework was measured.

[0065] Figure 3 shows an image visualized by a visualization program (Mercury) of the crystal structure of the metal-organic framework of Example 1. Referring to Figure 3, the image shows the average positions of atoms constituting the crystal structure of the metal-organic framework, obtained by repeatedly photographing the crystal structure of the metal-organic framework (a structure containing 100 titanium atoms, 200 carbon atoms, and 300 oxygen atoms) using the visualization program.

[0066] 2) Measurement of BET specific surface area: The surface area was measured by the low-temperature nitrogen adsorption method using a BELSORP-max II manufactured by BEL Japan. Each metal-organic framework was heated to 120°C in a vacuum for 12 hours to remove the moisture and residual solvent contained in the metal-organic framework. The vacuum-dried metal-organic framework was cooled with liquid nitrogen and the nitrogen gas adsorption curve was measured, and the surface area was then measured by the BET method using the adsorption curve.

[0067] 3) Measurement of VOC removal performance: The VOC removal performance of the metal-organic framework was measured using a measurement device shown in Fig. 1. Fig. 1 is a schematic diagram of a measurement device for evaluating the volatile organic compound removal performance of the organic compound adsorbent of the present invention.

[0068] A formaldehyde and nitrogen mixed gas with a concentration of 30 to 50 ppm stored in an external cylinder was injected into the mixing tank 10, and then nitrogen was added to dilute the formaldehyde concentration in the mixing tank to 10 ppm. After the 10 ppm concentration was stabilized, the formaldehyde was injected into the holder 20 containing the powdered metal-organic framework (organic compound adsorbent 30). The formaldehyde gas injected into the holder was pumped at a rate of 3 L per minute using a pump 50, and the volume of the holder 20 was approximately 39 cm. 3The flow rate through the metal organic framework was measured to be 76.4 cm / min. The injected formaldehyde was removed by adsorption while passing through the sample, resulting in a decrease in formaldehyde concentration. The formaldehyde concentration was measured using a measuring device (VOC concentration measuring device 40), and the change in formaldehyde concentration over time was recorded. As a result, a graph of the formaldehyde reduction over time for each metal organic framework is shown in Figure 2.

[0069] 4) Calculation of removal rate constant k and CADR: The removal rate constant k can be calculated using the following mathematical formula 2, and the CADR can be calculated using the following mathematical formula 3. The CADR is an index used to evaluate the performance of an air purifier, and indicates the amount of air that can be purified per unit area and unit time.

[0070] [Mathematical formula 2] C t =C i ×e -kt

[0071] In the above mathematical formula 2, C t is the concentration of the target organic compound (μmol / mol) after t minutes have elapsed, and C i is the initial target organic compound concentration (μmol / mol), k is the removal rate constant, and t is the elapsed time (min).

[0072] [Mathematical formula 3] CADR=-(V / t)×(ln(C t2 / C i2 )-ln(C t1 / C i1 ))

[0073] In the above mathematical formula 3, CADR is the purification capacity (m 3 / min), and V is the volume of the test chamber (m 3 ) where T is the measurement time (min) during the reduced operation, and C i1 is the particle concentration (particles / cm) at the measurement start point t=0 during natural attenuation 3 ) and C i2is the particle concentration (particles / cm) at the measurement start point t=0 during operation reduction. 3 ) and C t1 is the particle concentration (particles / cm3) during the measurement time t minutes during natural attenuation. 3 ) and C t2 is the particle concentration (particles / cm3) during measurement time t minutes during operation reduction 3 )

[0074] [Table 1]

[0075] 2 is a graph showing the formaldehyde reduction amount of the organic compound adsorbent of the present invention over time, as measured by the evaluation device. Referring to Table 1 and FIG. 2, Examples 1 to 3 satisfy the average diameter of the entrance and interior of the unit pore of the metal organic framework and the mathematical formula 1, and furthermore, the BET specific surface area is 500 m 2 / g or more, the removal rate constant k value is high at 0.03 or more. In contrast, in Comparative Examples 1 and 2, the BET specific surface area is 1000 m 2 / g or more, the average diameter of the pore entrance and the pore interior does not satisfy Equation 1, and therefore the removal rate constant is relatively low at less than 0.03. In addition, in Comparative Example 3, although Equation 1 is satisfied, the BET specific surface area is 500 m 2 / g, and the removal rate constant is significantly low. This indicates that the average diameter of the pore entrance and interior of the metal organic framework and the numerical range of Equation 1 are satisfied, and the BET specific surface area is 500 m 2 / g or more, it can be confirmed that a metal organic framework having the most efficient adsorption amount and adsorption rate can be obtained, and an organic compound adsorbent containing the metal organic framework can be obtained. [Explanation of symbols]

[0076] 10: Mixing tank 20: Holder 30: Organic compound adsorbent 40:VOC concentration measuring device 50: Pump 100: Titanium atom 200: Carbon atoms 300: Oxygen atom

Claims

1. It contains variable pores due to the bonding structure of metal ions and organic ligands, and has a BET specific surface area of 500m ２ / g or more and satisfying the following mathematical formula 1 under a gas flow with a flow rate of 1 cm / sec or more: a carbon-based support on which the metal-organic framework is supported; An organic compound adsorbent comprising: [Mathematical formula 1] 0.4≦x(nm) / y(nm)≦1.0 In the above mathematical formula 1, x is the average diameter (nm) of the entrance of a unit pore of the metal organic framework measured by any one or more of X-ray diffraction analysis, gas adsorption analysis, and mercury porosimeter; y is the average diameter (nm) of the unit pores of the metal organic framework measured by one or more of X-ray diffraction, gas adsorption, and mercury porosimeter; The x is 0.2 nm or more and 1.4 nm or less, The y is 0.5 nm or more and 2.2 nm or less.

2. The x is 0.35 nm or more and 1.2 nm or less, The adsorbent for organic compounds according to claim 1 , wherein y is 0.7 nm or more and 2.0 nm or less.

3. The adsorbent for organic compounds according to claim 1, wherein the metal organic framework has a removal rate constant value of 0.03 or more as calculated by the following mathematical formula 2: [Mathematical formula 2] C ｔ =C ｉ ×e －ｋｔ In the above mathematical formula 2, C ｔ is the concentration of formaldehyde (μmol / mol) after t minutes have elapsed, C ｉ is the initial formaldehyde concentration (μmol / mol), k is the elimination rate constant, t means elapsed time (min).

4. The BET specific surface area of the metal organic framework is 800 m ２ The adsorbent for organic compounds according to claim 1, wherein the adsorbent has a densitometric value of 0.1 / g or more.

5. 2. The organic compound adsorbent according to claim 1, wherein the metal ions are ions of one or more metals selected from the group consisting of sodium (Na), potassium (K), rubidium (Rb), calcium (Ca), strontium (Sr), barium (Ba), scandium (Sc), yttrium (Y), hafnium (Hf), niobium (Nb), chromium (Cr), silver (Ag), indium (In), germanium (Ge), tin (Sn), aluminum (Al), iron (Fe), molybdenum (Mo), tungsten (W), vanadium (V), zinc (Zn), zirconium (Zr), copper (Cu), magnesium (Mg), manganese (Mn), nickel (Ni), titanium (Ti), and lanthanum transition metals.

6. The adsorbent for organic compounds according to claim 1 , wherein the organic ligand contains two or more functional groups capable of bonding with the metal ions.

7. 2. The adsorbent for organic compounds according to claim 1, wherein the organic ligand is at least one selected from the group consisting of imidazole, alkylimidazole, alkoxyimidazole, terephthalic acid, aminoterephthalic acid, trimesic acid, fumaric acid, and maleic acid.

8. The adsorbent for organic compounds according to claim 1 , wherein the carbon-based support comprises at least one selected from the group consisting of carbon nanotubes, graphene, graphite, amorphous carbon, carbon black, and activated carbon.

9. The adsorbent for organic compounds according to claim 8 , wherein the metal organic framework is contained in an amount of 3 to 95 parts by weight relative to 100 parts by weight of the carbon-based support.

10. A gas blower comprising the adsorbent for organic compounds according to any one of claims 1 to 9, wherein a gas flow rate exists.

Images