Filter

Abstract

To provide a filter capable of reducing pressure loss at time of air passing.SOLUTION: A filter in which a metal-organic framework is supported on a substrate, wherein the filter that has undergone a specific pretreatment (a) and a water adsorption treatment (b) satisfies the following requirements (R1) and (R2) when air at high temperature and low humidity is passed through it at a predetermined airflow rate. Requirement (R1): Obtain graph P, where the horizontal axis represents time (seconds) and the vertical axis represents the cumulative amount of water desorbed per gram of filter (g), and graph Q, where the horizontal axis represents time (seconds) and the vertical axis represents the temperature (°C) of the air downstream of the filter, grasp the time t (seconds) at which the air temperature downstream of the filter reaches its lowest point T on graph Q, and the absolute value of the slope of the straight line connecting the point (t, P(t)) on graph P at time t and the origin is 9×10-4 or greater. Requirement (R2): The cumulative amount of water desorbed after 600 seconds is 0.133 g or more per gram of filter.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a filter having a metal-organic framework supported on a substrate. [Background technology]

[0002] Metal organic frameworks (MOFs), also known as porous coordination polymers, are a type of material that form porous structures through coordination bonds between metal ions and organic ligands. They are expected to be used in applications that take advantage of their gas adsorption and desorption properties, as well as in catalysts.

[0003] For example, Patent Document 1 describes the use of a moisture absorbing plate having a metal organic framework attached to its surface as a component of a humidity control device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Korean Patent Publication No. 10-2020-0140435 Summary of the Invention [Problem to be solved by the invention]

[0005] It is desirable that a filter having a metal organic framework attached to the surface of a substrate has a small pressure loss when a gas is passed through the filter.

[0006] Therefore, an object of the present disclosure is to provide a filter that can reduce pressure loss when gas passes through it. [Means for solving the problem]

[0007] The present disclosure that achieves the above object is as follows. [1] A filter in which a metal organic framework is supported on a substrate, The substrate has one or more through holes, The filter was subjected to a pretreatment (a) in which the filter was kept in an air atmosphere at a temperature of 80°C and a relative humidity of 3 to 5% for 30 minutes, and then kept in a sealed bag until the temperature reached 25°C. The filter was then subjected to a water adsorption treatment (b) in which the filter subjected to the pretreatment (a) was kept in an air atmosphere at a temperature of 20°C and a relative humidity of 70% for 600 seconds. The filter was then subjected to a water adsorption treatment (b) in which air at a temperature of 78°C and a relative humidity of 3 to 5% was blown at a wind speed of 45 m / s in the axial direction of the through-holes. 3 A filter that satisfies the following requirements (R1) and (R2) when flowing at / h. Requirement (R1): Obtain graph P, with the horizontal axis representing time (seconds) and the vertical axis representing the cumulative amount of water desorbed (g) per 1 g of filter, and graph Q, with the horizontal axis representing time (seconds) and the vertical axis representing the temperature of the air downstream of the filter (°C). Determine the time t (seconds) at which the temperature of the air downstream of the filter reaches its lowest point T on graph Q, and determine whether the absolute value of the slope of the line connecting point (t, P(t)) on graph P at time t to the origin is 9 x 10 -4 That's all. Requirement (R2): The cumulative amount of water released after 600 seconds is 0.133 g or more per 1 g of filter. [2] The cross-sectional area of ​​the substrate cross section perpendicular to the axial direction of the through hole is 300 to 40,000 mm 2 and the cross-sectional area is 1 cm 2 The number of holes per cell is 10 to 150 cells / cm 2 The filter according to [1], [3] The metal organic framework comprises at least one metal element M selected from the group consisting of elements in periods 4 to 6 and groups 3 to 12 of the long-form periodic table, Al, Ga, and In, and R(COO - ) n (R is an n-valent group, n is an integer of 2 or more). [Effects of the Invention]

[0008] The filter of the present disclosure can reduce pressure loss when gas passes through it. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram showing the cross-sectional shape of a substrate used in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] <filter> The filter of the present disclosure comprises a substrate carrying a metal-organic framework. The substrate has one or more through-holes. The filter is subjected to a pretreatment (a) in which the filter is kept in an air atmosphere at a temperature of 80°C and a relative humidity of 3 to 5% for 30 minutes, and then kept in a sealed bag until the temperature reaches 25°C. The filter subjected to the pretreatment (a) is then subjected to a water adsorption treatment (b) in which the filter is kept in an air atmosphere at a temperature of 20°C and a relative humidity of 70% for 600 seconds. The filter is then subjected to a water adsorption treatment (b) in which air at a temperature of 78°C and a relative humidity of 3 to 5% is blown at a wind speed of 45 m / s in the axial direction of the through-holes. 3 When flowing at 1000 kJ / h, the filter of the present disclosure satisfies the following requirements (R1) and (R2).

[0011] Requirement (R1): Obtain graph P, with the horizontal axis representing time (seconds) and the vertical axis representing the cumulative amount of water desorbed (g) per 1 g of filter, and graph Q, with the horizontal axis representing time (seconds) and the vertical axis representing the temperature of the air downstream of the filter (°C). Determine the time t (seconds) at which the temperature of the air downstream of the filter reaches its lowest point T on graph Q, and determine whether the absolute value of the slope of the line connecting point (t, P(t)) on graph P at time t to the origin is 9 x 10 -4 That's all. Requirement (R2): The cumulative amount of water released after 600 seconds is 0.133 g or more per 1 g of filter.

[0012] By passing air at a temperature of 78°C and a relative humidity of 3 to 5% through a filter that has undergone pretreatment (a) and adsorption treatment (b) at the above-mentioned air velocity, the moisture adsorbed by the filter can be desorbed. Requirements (R1) and (R2) both describe the characteristics of the filter when desorbing moisture adsorbed by the filter. In a filter of the present disclosure that satisfies requirements (R1) and (R2), it is believed that the MOFs are supported on the substrate in a dispersed state without agglomeration. Areas where the MOFs are aggregated are prone to adsorbing moisture from the surrounding environment (e.g., a temperature of 10 to 40°C and a relative humidity of 5 to 80% RH, or a temperature of 20 to 35°C and a relative humidity of 20 to 50% RH) and forming water droplets. However, in a filter of the present disclosure that satisfies requirements (R1) and (R2), it is believed that pressure loss can be reduced, possibly because the areas where such water droplets accumulate can be reduced.

[0013] When the filter begins to desorb the moisture it had adsorbed, the temperature of the air downstream of the filter drops, and when desorption is almost complete, the temperature of the air downstream of the filter begins to rise. In other words, the point T in graph Q where the temperature of the air downstream of the filter is lowest means the point where most of the moisture adsorbed in adsorption process (b) has been desorbed. Therefore, the absolute value of the slope of the line specified in requirement (R1) (hereinafter referred to as slope k) is 9 x 10 -4 The above means that the filter can quickly desorb the adsorbed water (hereinafter referred to as desorption rate characteristic (1)).

[0014] Furthermore, in requirement (R2), if the cumulative amount of water released after 600 seconds is 0.133 g or more per 1 g of filter, this means that the absolute amount of water that the filter can release is large (hereinafter referred to as release amount characteristic (2)).

[0015] For both the desorption rate characteristic (1) and the desorption amount characteristic (2), the filter of the present disclosure, which has been subjected to the pretreatment (a) and the water adsorption treatment (b), is subjected to air at a temperature of 78°C and a relative humidity of 70% blown in the axial direction of the through-holes at a wind speed of 45 m / s. 3 It is measured by a test flowing at 1 / s.

[0016] Specifically, air (inlet air) at a temperature of 78°C and a relative humidity of 70% is prepared and passed through a filter that has undergone pretreatment (a) and water adsorption treatment (b), while the temperature X (°C) and relative humidity Y (%) of the air downstream of the filter (outlet air) are measured. The saturated water vapor pressure is calculated from the temperature values ​​for the inlet air and outlet air using the following equation (1). The temperature X (°C) and relative humidity Y (%) of the air downstream of the filter can be measured at a position 0 to 30 cm downstream along the axis of the through-holes from the downstream surface of the filter.

[0017]

number

[0018] In the above formula, T is the air temperature (℃), and e ω is the saturated water vapor pressure (g / m 2 )

[0019] Next, the relative humidity (%) and the saturated water vapor pressure (g / m 2 ) the absolute amount of moisture (g / kg) contained in 1 kg of air can be calculated based on the following formula (2): Relative humidity (%) = 100 × water vapor pressure of air (g / m 2 ) / {Saturated water vapor pressure (g / m 2 )}···(2)

[0020] The absolute amount of moisture contained in 1 kg of air is calculated for both the inlet air and the outlet air, and the absolute amount of moisture in 1 kg of air on the outlet side is subtracted from the absolute amount of moisture in 1 kg of air on the inlet side (a negative value) to calculate the absolute value (g / kg). Because the temperature and humidity on the outlet side change, measurements are taken over time, and the absolute value of the difference between the absolute amount of moisture in 1 kg of air on the inlet side and the absolute amount of moisture in 1 kg of air on the outlet side is integrated, and multiplied by the total amount of air (kg) that passed through the filter to estimate the amount of moisture desorbed from the filter.

[0021] The upper limit of the absolute value of the slope k is, for example, 1.5 × 10 -3 or less, preferably 1.0 × 10 -3 or less, more preferably 9.5 × 10 -4 The absolute value of the slope k is 9×10 -4 ~1.5×10 -3 Preferably, it is 9 x 10 -4 ~1.0×10 -3 is more preferable, and 9×10 -4 ~9.5×10 -4 is more preferred.

[0022] The cumulative amount of water released after 600 seconds is preferably 0.15 g or more per gram of filter, more preferably 0.16 g or more, and even more preferably 0.17 g or more, and the upper limit may be, for example, 0.23 g. The cumulative amount of water released after 600 seconds is preferably 0.133 to 0.23 g per gram of filter, more preferably 0.15 to 0.23 g, even more preferably 0.16 to 0.23 g, and even more preferably 0.17 to 0.23 g.

[0023] In this disclosure, the slope k is 9×10 -4 ~1.5×10 -3 and the cumulative amount of water desorbed after 600 seconds is preferably 0.15 to 0.23 g, and the slope k is 9×10 -4 ~1.0×10 -3 and the cumulative amount of water desorbed after 600 seconds is more preferably 0.16 to 0.23 g, and the slope k is 9×10 -4 ~9.5×10 -4 and it is more preferable that the cumulative amount of water desorbed after 600 seconds is 0.17 to 0.23 g.

[0024] The amount of MOF supported per unit area of ​​the filter is, for example, 65 g / m 2 or more, and 70 g / m 2 More than 75g / m 2 More preferably, 120 g / m 2The amount of MOF supported per 1 g of filter is preferably 0.40 g or more, and the upper limit may be, for example, 0.7 g or less. The amount of MOF supported per unit area of ​​the filter is, for example, 65 g / m 2 ~120g / m 2 and 70 g / m 2 ~120g / m 2 is preferred, and 75 g / m 2 ~120g / m 2 The amount of MOF supported is preferably 0.40 g to 0.7 g per 1 g of filter.

[0025] The pressure loss measured according to the procedures in the Examples described below is preferably 25 Pa or less, more preferably 25 to 10 Pa, and even more preferably 22 to 10 Pa, when the face velocity is 1.0 m / s. The pressure loss is preferably 42 Pa or less, more preferably 42 to 20 Pa, and even more preferably 35 to 20 Pa, when the face velocity is 1.5 m / s.

[0026] <Metal organic structure> MOFs are composed of metals and organic ligands. Examples of the metal element M constituting MOFs include at least one element selected from the group consisting of elements in periods 4 to 6 and groups 3 to 12 of the long-form periodic table, Al, Ga, and In, and preferably at least one element selected from the group consisting of Al, Ga, In, Ti, Zr, Hf, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, with Al being particularly preferred.

[0027] If the composition of the supported MOF is unknown, it is possible to identify the metal element M of the MOF, for example, by cutting the filter at a cross section where the substrate and the MOF supported on the substrate can be observed, and measuring the concentration profile in the depth direction using SEM-EDX or the like. In the filter of the present disclosure, the MOF is supported on the surface of the substrate, and therefore the element whose concentration near the filter surface is higher than the concentration inside the substrate in the concentration profile in the depth direction is the metal element of the MOF.

[0028] The organic ligands include R(COO- ) n (R is an n-valent group, n is an integer of 2 or more). R is preferably an aliphatic chain hydrocarbon group, an aliphatic cyclic hydrocarbon group, an aliphatic heterocyclic hydrocarbon group (a group in which one or more carbon atoms of an aliphatic cyclic hydrocarbon group are replaced with heteroatoms), an aromatic hydrocarbon group, or an aromatic heterocyclic hydrocarbon group (a group in which one or more carbon atoms of an aromatic hydrocarbon group are replaced with heteroatoms), and most preferably an aromatic hydrocarbon group. The number of carbon atoms in R is preferably 2 to 30, more preferably 4 to 24, and even more preferably 6 to 18. n is preferably 2 or more and 4 or less, more preferably 2 or more and 3 or less, and most preferably 2.

[0029] The above-mentioned aliphatic chain hydrocarbon group, aliphatic cyclic hydrocarbon group, aliphatic heterocyclic hydrocarbon group, aromatic hydrocarbon group, and aromatic heterocyclic hydrocarbon group may further contain one or more functional groups X which are -OH and / or -NH.

[0030] The aliphatic chain hydrocarbon group may be linear or branched, and may be a saturated or unsaturated hydrocarbon group. Examples of the aliphatic chain hydrocarbon group include groups obtained by removing n hydrogen atoms from ethane, ethylene, acetylene, butane, butene, or hexane.

[0031] Examples of the aliphatic cyclic hydrocarbon group include groups in which n hydrogen atoms have been removed from cyclopropane, cyclobutane, cyclohexane, cyclooctane, norbornene, or adamantane.

[0032] Examples of the aliphatic heterocyclic hydrocarbon group include groups in which n hydrogen atoms have been removed from pyrrolidine, piperidine, piperazine, or morpholine.

[0033] The preferred ranges for the number of carbon atoms in the aromatic hydrocarbon group are, in order, 6 or more and 30 or less, 6 or more and 24 or less, 6 or more and 18 or less, 6 or more and 12 or less, and 6 or more and 10 or less. Specifically, the aromatic hydrocarbon group is a group in which n (preferably 2 or 3) hydrogen atoms have been removed from benzene or biphenyl, and particularly a group in which n (preferably 2 or 3) hydrogen atoms have been removed from benzene.

[0034] The aromatic hydrocarbon group is preferably any one of the following formulae (A-1) to (A-9), more preferably any one of the formulae (A-1) to (A-3), and even more preferably formula (A-2). In the following formulae (A-1) to (A-9), * represents a bond.

[0035] [ka]

[0036] In the formulae (A-1) to (A-9), at least one of the hydrogen atoms bonded to the carbon atoms may be substituted with -OH and / or -NH2, or the hydrogen atoms bonded to the carbon atoms may not be substituted.

[0037] Examples of the aromatic heterocyclic hydrocarbon group include groups in which n hydrogen atoms have been removed from pyrrole, pyrazole, imidazole, thiazole, oxazole, pyridine, pyrimidine, pyridazine, pyrazine, or triazine.

[0038] The metals and organic ligands constituting the MOF can be appropriately combined within the above-mentioned preferred ranges. For example, the metal may be at least one selected from the group consisting of Al, Ga, In, Ti, Zr, Hf, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, and the organic ligand may be R(COO - ) n In the present invention, preferred MOFs are carboxylates in which R is an aromatic hydrocarbon group and n is 2 or 3, the metal is Al, and the organic ligand is R(COO - ) nAn MOF in which R is any one of the above formulae (A-1) to (A-3) and n is 2 is more preferred.

[0039] The molar ratio (metal ion / organic ligand) of metal ion (total amount if multiple types) to organic ligand (total amount if multiple types) is preferably 0.1 or more, more preferably 0.3 or more, even more preferably 0.5 or more, particularly preferably 0.9 or more, and is preferably 5 or less, more preferably 4 or less, even more preferably 3 or less, particularly preferably 2.5 or less. The molar ratio is preferably 0.1 to 5, more preferably 0.3 to 4, even more preferably 0.5 to 3, and even more preferably 0.9 to 2.5. The organic ligands that make up the MOF are the above R(COO-) n If the carboxylate is represented by R(COO-) n The amount of metal constituting the MOF is preferably 0.8×n to 1.5×n moles, and more preferably 0.8×n to 1.2×n moles, per mole of the metal.

[0040] The BET specific surface area of ​​MOF is, for example, 450 to 800 m 2 / g, and 500 to 750m 2 / g, and more preferably 530 to 700m 2 / g, and more preferably 580 to 700m 2 / g is particularly preferred.

[0041] MOFs can be produced by a conventional method, for example, by reacting a metal compound containing metal ions constituting the MOF with an organic compound serving as an organic ligand in a solvent. More specifically, it is preferable to prepare a solution B in which a metal compound containing metal ions is completely dissolved, and a solution A in which an organic compound serving as an organic ligand is completely dissolved, and then dropwise add one of them to the other to cause the two to react with each other.

[0042] The metal compound containing the metal ion constituting the MOF is preferably a metal sulfate, nitrate, acetate, chloride, bromide or alkoxide, more preferably a metal sulfate. The organic compound that becomes the organic ligand constituting the MOF is R(COOH) n (R and n are the same as above) is preferable.

[0043] The solvent is preferably water, an alcohol solvent such as methanol or ethanol, or an amide solvent such as N,N-dimethylformamide, and the like, and one of these solvents may be used alone or in combination. In particular, when a metal compound containing a metal ion constituting the MOF is reacted with an organic compound serving as an organic ligand in the presence of water as a solvent, the reaction is preferably carried out in the presence of a tertiary amine such as triethylamine.

[0044] After the reaction is complete (preferably after the dropwise addition is complete), the reaction mixture is refluxed, stirred, or left to stand for approximately 5 minutes to 100 hours at room temperature (e.g., 25°C) to 200°C, and the reaction product is separated from the solvent by centrifugation or filtration, washed, and dried to obtain the desired MOF.

[0045] <Base material> The composition of the substrate can be, for example, a substrate having at least a surface made of metal, metal oxide, or the like, and a substrate having at least a surface made of silicate is preferred, and the silicate may contain at least one of Ca, Mg, Fe, Na, and Al. The substrate has one or more through holes, and the preferred outer shape is a columnar shape. The columnar shape is preferably, for example, a cylindrical, rectangular, or elliptical cylinder. The number of through holes is preferably two or more, and the hole shape in a cross section perpendicular to the axial direction may be a circle or a polygon such as a triangle, a rectangle, or a hexagon, including polygons with rounded vertices. The cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole is 300 to 40,000 mm 2 is preferable, and 500 to 35,000 mm 2 is more preferable, and 5,000 to 30,000 mm2 is more preferable, and 10,000 to 25,000 mm 2 The length of the substrate (the axial length of the through-holes) is preferably 10 to 200 mm, more preferably 20 to 150 mm. Cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole: 1 cm 2 The number of cells (holes) per square centimeter is 10 to 150 cells / cm. 2 is preferred, and 20 to 100 cells / cm 2 More preferably, 30 to 80 cells / cm 2 is more preferred. The average area of ​​one cell in the cross section of the substrate perpendicular to the axial direction of the through-hole is 0.5 to 10 mm 2 is preferable, and 1 to 8 mm 2 More preferably, 2 to 6 mm 2 is more preferred. The thickness of the inner wall separating the cells is preferably 10 to 1000 μm, more preferably 50 to 500 μm, and even more preferably 100 to 300 μm.The thickness of the outer wall of the substrate is also preferably within the above range. The total surface area of ​​the substrate, including the front and back of the inner and outer walls, is 0.01 to 2 m 2 It is preferable that the length is 0.1 to 1.8 m. 2 It is more preferable that the thickness is 0.5 to 1.5 m. 2 It is more preferable that:

[0046] In the present disclosure, the cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole is 300 to 40,000 mm 2 and the cross-sectional area is 1 cm 2 The number of holes per cell is 10 to 150 cells / cm 2 It is preferable that the cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole is 500 to 35,000 mm 2 and the cross-sectional area is 1 cm 2 The number of holes per cell is 20 to 100 cells / cm 2 It is more preferable that the cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole is 10,000 to 25,000 mm 2 and the cross-sectional area is 1 cm 2 The number of holes per cell is 30 to 80 cells / cm2 It is more preferable that:

[0047] <Filter manufacturing method> The filter of the present disclosure can be produced by impregnating a substrate with a slurry containing MOFs, removing the slurry, and then drying it. It is particularly important to appropriately adjust the MOF concentration in the slurry and the number of applications, as well as to adjust the amount of MOFs supported per unit area of ​​the substrate. More specifically, it is preferable to apply a slurry with a high MOF concentration (e.g., 20 to 40% by mass) to the substrate once and then dry it. The preferred range of the amount of MOFs supported per unit area of ​​the substrate is as described above. The amount of MOFs supported per unit area of ​​the substrate can be adjusted by adjusting the time the substrate is immersed in the MOF-containing slurry, or by vibrating the substrate after immersion in the MOF-containing slurry to adjust the amount of slurry.

[0048] The slurry preferably contains a solvent, an emulsifier, a dispersant, and a pH adjuster in addition to the MOF, and the pH of the slurry is preferably 4 to 5. The drying temperature and time for the substrate impregnated with the MOF-containing slurry are, for example, 30 to 600°C and 1 to 24 hours.

[0049] <Application> The filter of the present disclosure is suitable for adsorption and removal of gases and organic molecules, and can also be used as a replaceable cartridge as a component of a humidity control device, etc. Examples of gases include water (water vapor), carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gases, hydrogen sulfide, ammonia, sulfur oxides, nitrogen oxides, and siloxanes. Examples of organic molecules include hydrocarbons having 5 to 8 carbon atoms, alcohols having 1 to 8 carbon atoms, aldehydes having 1 to 8 carbon atoms, carboxylic acids having 1 to 8 carbon atoms, ketones having 1 to 8 carbon atoms, amines having 1 to 8 carbon atoms, esters having 1 to 8 carbon atoms, and amides having 1 to 8 carbon atoms. The organic molecules may contain an aromatic ring. [Example]

[0050] The present disclosure will be described in more detail below with reference to examples. The present disclosure is not limited to the following examples, and can of course be implemented with appropriate modifications within the scope of the above and below-described aims, all of which are encompassed within the technical scope of the present disclosure.

[0051] [Measurement of BET specific surface area of ​​MOF] Since the adsorption area of ​​nitrogen molecules is known in advance, the amount of gas molecules adsorbed only on the sample surface was measured, and the surface area of ​​the MOF sample was measured using the BET adsorption isotherm. Sample preparation: To remove water from the sample, the sample was heated under reduced pressure at 10 Pa or less and 200°C overnight. Equipment: Microtrac BEL Co., Ltd. BELSORP-mini Pretreatment conditions: (ai) Place a volume-reducing glass rod (for standard sample tubes) in the standard sample tube and plug it with a quick seal. Prepare this sample tube set with the samples to be measured (up to three samples per measurement), connect it to the pretreatment device (BELPREP VACII), evacuate the air from inside the sample tube, and then introduce N2 gas (purity 99.999% or higher) up to atmospheric pressure. (a-ii) Then, remove the sample tube from the pretreatment machine and measure its weight three times using a precision balance (displaying four or more decimal places) to obtain the average (W1). When using a precision balance, use an ionizer to eliminate the effects of static electricity. (a-iii) Weigh out approximately 50 mg of the sample to be measured onto a piece of medicine paper, and use a long-footed funnel to place the sample directly into the spherical part at the bottom of the standard sample tube. (a-iv) Return the glass rod to the sample tube, plug it with a quick seal, and then measure the total weight once to provisionally confirm the amount of sample added. (av) The sample tube containing the sample is connected to the pretreatment device, and the inside of the sample tube is evacuated. (a-vi) After the pressure inside the sample tube has reached a sufficiently low level, heating begins (vacuuming continues). Measurement conditions: (bi) After the pretreatment (vacuum heating) is completed, the sample tube is cooled while being kept under reduced pressure, and after it has returned to room temperature, N2 gas is introduced up to atmospheric pressure and the tube is removed from the apparatus. (b-ii) After pretreatment, measure the weight of the sample tube containing the sample three times using a precision balance and obtain the average (W2). Calculate W2 - W1 to obtain the weight of the sample. (b-iii) Enter the sample weight and information on N2 gas at liquid nitrogen temperature (such as the second virial coefficient) into the measurement software, enter the relative pressure you want to measure, and press the measurement start button. Then, follow the instructions in the software to install a Dewar vessel filled with liquid nitrogen and a sample tube, and perform the measurement.

[0052] [MOF loading (g / m 2 ) Measurement The weight of the filter substrate before supporting the MOF and the weight of the filter after supporting the MOF were measured, and the difference in weight was calculated as the surface area (m 2 ) was used to calculate the amount of MOF supported per unit area of ​​the filter.

[0053] [Measurement of desorption characteristics] The filters manufactured in the Examples and Comparative Examples were subjected to a pretreatment (a) in which they were held in an air atmosphere at a temperature of 80°C and a relative humidity of 3 to 5% for 30 minutes, and then held in a sealed bag until the temperature reached 25°C, and the weight was immediately measured. Next, the apparatus was stabilized under conditions of a temperature of 20°C and a relative humidity of 70%, and the filters subjected to the pretreatment (a) were subjected to a water adsorption treatment (b) in which they were held in an air atmosphere at a temperature of 20°C and a relative humidity of 70% for 600 seconds, and the weight was immediately measured, and the filters after the adsorption treatment were placed in an aluminum zip-top bag. Next, the apparatus was stabilized so that air at a temperature of 78°C and a relative humidity of 3 to 5% could be stably supplied, and a wind speed of 45 m / s was blown in the axial direction of the through-holes. 3 The temperature and relative humidity of the air passing through the filter were measured over time. Measurements were continued until there was no change in the temperature or humidity of the outflowing air. The absolute amount of moisture contained in 1 kg of air was calculated using equations (1) and (2) for both the inlet and outlet air. The absolute amount of moisture in 1 kg of air was subtracted from the absolute amount of moisture in 1 kg of outlet air (negative value), and the resulting value was multiplied by the total amount of air (kg) passing through the filter to calculate the amount of moisture desorbed (g). Graph P, with time (seconds) on the horizontal axis and the cumulative amount of moisture desorbed per gram of filter (negative value), and graph Q, with time (seconds) on the horizontal axis and the temperature of the air downstream of the filter (°C), were also obtained. The time t (seconds) at which the temperature of the air downstream of the filter reached its lowest point T on graph Q was determined. The absolute value of the slope of the line connecting point (t, P(t)) on graph P at time t to the origin was calculated, and the absolute value of the cumulative amount of moisture desorbed (per gram of filter) after 600 seconds was also calculated.

[0054] [Pressure loss measurement] A filter manufactured in the same manner as in the Examples and Comparative Examples was attached to a pressure loss measuring device so that no gap was formed between the filter and the pressure loss measuring device in a cross section perpendicular to the axial direction of the through-holes, and the intake fan was operated. The differential pressure of the set nozzle was measured with a differential pressure gauge and converted into air volume. Furthermore, the air volume was converted into a surface air velocity from the ventilation area of ​​the sample, and the resistance value (pressure loss, unit: Pa) at that time was measured. The fan frequency was changed, and the resistance value (pressure loss, unit: Pa) was measured at four air volume points, and the resistance value for each surface air velocity was calculated and plotted to obtain Y = aX b Using the power approximation formula (where X is the surface wind speed (m / s) and Y is the pressure loss (Pa)), the pressure loss was calculated when the surface wind speed was 1.0 m / s and 1.5 m / s. For the pressure loss measurement, a substrate with a cross-sectional area of ​​approximately 53600 mm 2 The filters used were prepared in the same manner as in the following Examples and Comparative Examples, except that the substrate used had approximately 61 layers and a cylindrical outer shape. The environment during the production of the filters used in the pressure loss measurements and before the pressure loss measurements was a temperature of 20 to 35°C and a relative humidity of 20 to 50% RH.

[0055] (Preparation Example 1-1: Preparation of Metal-Organic Framework 1) In a 13-L autoclave, 3.91 mol of isophthalic acid and 3,200 mL of DMF (N,N-dimethylformamide) were mixed at 25 °C and completely dissolved to obtain solution A. Separately, 3.75 mol of Al2(SO4)3·nH2O (n = 14–18) were mixed with 4,800 mL of ion-exchanged water to prepare solution B. Solution B was added dropwise to solution A over 45 minutes at 25 °C. The resulting mixture was then refluxed at 135 °C for 12 hours to obtain a suspension. This was then pressure-filtered, and the precipitated solid was pressure-filtered and washed three times with 1,500 mL of DMF and three times with 1,500 mL of methanol. The resulting filter cake was dried in a vacuum oven at 50 °C for 3 hours to obtain 865.23 g of the product (MOF1) (yield: 94%). The BET specific surface area of ​​MOF1 was 612 m 2 / g.

[0056] (Preparation Example 1-2: Preparation of Metal-Organic Framework 2) Solution A was prepared by dissolving 3.50 mol of isophthalic acid and 9.94 mol of triethylamine in 8060 mL of water in a 13 L autoclave. Solution B was prepared by mixing 2.54 mol of Al2(SO4)3·nH2O (n = 14–18) with 540 mL of ion-exchanged water to completely dissolve the two. Solution B was added dropwise to solution A at 25 °C over 45 min. The mixture was then refluxed at 100 °C for 12 h to obtain a suspension. This was then pressure filtered, and the precipitated solid was washed twice with 2000 mL of ion-exchanged water and twice with 2000 mL of methanol. The resulting filter cake was dried in a vacuum oven at 100 °C for 6 h to obtain 721.97 g of the product (MOF2) (yield: 97.9%). The BET specific surface area of ​​MOF2 was 660 m 2 / g.

[0057] (Preparation Example 2: Preparation of slurry containing metal-organic framework) The metal-organic framework obtained in Preparation Example 1-1 or Preparation Example 1-2 and a solvent were mixed to prepare a slurry containing the metal-organic framework having a pH of 4 to 5.

[0058] Example 1 A substrate having dimensions of 130 mm × 130 mm × length 30 mm and containing wollastonite on the surface was immersed in a slurry prepared by mixing a metal organic framework in an amount to give the concentration shown in Table 1 below in the same manner as in Preparation Example 2, and then pulled out and dried to prepare a filter in which the metal organic framework was supported on the substrate.

[0059] The base material is composed of a corrugated corrugated core 1 as shown in Figure 1, and a cover sheet 2 and backing sheet 3 bonded to the core 1. The core has a layered structure with a corrugation height h of approximately 1.7 mm and a corrugation width p (pitch) of approximately 2.7 mm, with a total of 76 layers.

[0060] Example 2, Comparative Examples 1 and 2 A substrate having a size shown in Table 1 was immersed in a slurry prepared at a MOF concentration shown in Table 1, and then the substrate was pulled out and dried (first time). After that, the procedure was repeated a second, third, and fourth time at the concentrations shown in Table 1, and a filter having a metal organic framework supported on the substrate was produced in the same manner as in Example 1.

[0061] The conditions and results of the examples and comparative examples are shown in Tables 1 and 2.

[0062] [Table 1]

[0063] [Table 2] [Explanation of symbols]

[0064] 1...Center core 2. Cover 3. Backing paper h: Height of the core step p: Width of the core step (pitch)

Claims

1. A filter in which a metal organic framework is supported on a substrate, the substrate has one or more through holes; The filter was subjected to a pretreatment (a) in which the filter was kept in an air atmosphere at a temperature of 80°C and a relative humidity of 3 to 5% for 30 minutes, and then kept in a sealed bag until the temperature reached 25°C. The filter was then subjected to a water adsorption treatment (b) in which the filter subjected to the pretreatment (a) was kept in an air atmosphere at a temperature of 20°C and a relative humidity of 70% for 600 seconds. The filter was then subjected to a water adsorption treatment (b) in which air at a temperature of 78°C and a relative humidity of 3 to 5% was blown at a wind speed of 45 m / s in the axial direction of the through-holes. ３ A filter that satisfies the following requirements (R1) and (R2) when flowing at 1000 / h. Requirement (R1): Obtain a graph P with the horizontal axis representing time (seconds) and the vertical axis representing the cumulative amount of water desorbed (g) per 1 g of filter, and a graph Q with the horizontal axis representing time (seconds) and the vertical axis representing the temperature of the air downstream of the filter (°C). Determine the time t (seconds) at which the temperature of the air downstream of the filter reaches its lowest point T on graph Q, and verify that the absolute value of the slope of the line connecting the point (t, P(t)) on graph P at time t to the origin is 9 x 10 －４ That's all. Requirement (R2): The cumulative amount of water desorbed after 600 seconds is 0.133 g or more per 1 g of filter.

2. The cross-sectional area of ​​the substrate perpendicular to the axial direction of the through-hole is 300 to 40,000 mm ２ and the cross-sectional area is 1 cm ２ The number of holes per cell is 10 to 150 cells / cm ２ 2. The filter according to claim 1, wherein

3. The metal organic framework comprises at least one metal element M selected from the group consisting of elements in periods 4 to 6 and groups 3 to 12 of the long-form periodic table, Al, Ga, and In, and R(COO － ) ｎ 3. The filter according to claim 1, wherein the organic ligand comprises at least one selected from the group consisting of carboxylates represented by the formula (I) (where R is an n-valent group, and n is an integer of 2 or more).

Images