Absorbing sheet, sheet processed by steps, laminate processed by steps, absorbing element, and dehumidifier

Abstract

The purpose of the present disclosure is to provide an absorbing sheet, a sheet processed by steps, a laminate processed by steps, an absorbing element, and a dehumidifier. Provided are an absorbing sheet, a sheet processed by steps, a laminate processed by steps, an absorbing element, and a dehumidifier.

Description

Adsorption sheet, corrugated sheet, corrugated laminate, adsorption element, and dehumidifier

[0001] The present disclosure relates to an adsorbent sheet, a corrugated sheet, a corrugated laminate, an adsorbent element, and a dehumidifier.

[0002] Patent Document 1 discloses an adsorption element (honeycomb-shaped) containing 60 to 85% by weight of a zeolite adsorbent with a pore size of 7 Å or more and the following binders A and B, as well as a dehumidifier or exhaust gas treatment device that uses the adsorption element. A: At least one polymer selected from polyvinyl alcohol-based polymers, polyacrylonitrile-based polymers, polyethylene-based polymers, and polyester-based polymers. B: Heat-resistant material.

[0003] Patent Document 2 discloses an adsorption element in which a modified vinyl acetate adhesive is used in an element (honeycomb shape) containing an adsorbent, and the content of the adhesive in the element is 1 to 15 wt %, as well as a dehumidifier or an exhaust gas treatment device that uses the adsorption element.

[0004] Patent Document 3 discloses a dehumidifying member having a honeycomb structure, the honeycomb structure including a flat substrate and a corrugated substrate, a contact portion where the crests of the corrugated substrate and the flat substrate contact, and an air vent portion, the contact portion including an adhesive bonded portion and silica gel formed on the air vent portion side of the adhesive portion, the components constituting the adhesive being different from the components of the silica gel formed on the air vent portion side of the adhesive portion, and a dehumidifying rotor including the dehumidifying member.

[0005] Publication No. 2004-268020 Publication No. 2005-177673 Publication No. 2021-181072

[0006] The present disclosure aims to provide a new adsorbent sheet, a corrugated sheet, a corrugated laminate, an adsorbent element, and a dehumidifier.

[0007] Lithium battery manufacturing plants must dehumidify, or the quality of the lithium batteries will be affected. Because lithium reacts strongly with moisture, lithium manufacturing plants must set the dew point low. Pharmaceutical manufacturing plants sometimes require a low dew point, and such manufacturing processes are carried out in dry rooms.

[0008] To create a dry room environment, an adsorption-type dehumidification method is used, using an adsorption element made of zeolite, silica gel, etc. Such rotors desorb the adsorbed moisture through high-temperature regeneration treatment at 140°C or higher, continuously producing dehumidified air. Therefore, operation requires a large amount of energy.

[0009] Due to the background of global warming, there is a demand for energy conservation, which means that there is a need to improve dehumidification performance to achieve energy conservation.

[0010] Conventionally, elements have been manufactured by directly immersing a honeycomb structure or sheet in a silica sol liquid to synthesize silica gel (Patent Document 3). This technique results in a high density of silica gel, low porosity, and poor diffusion of the gas to be treated within the adsorption element, making it difficult to expect improvements in dehumidification performance.

[0011] The present disclosure encompasses the following adsorbent sheets, corrugated sheets, corrugated laminates, adsorbent elements, and dehumidifiers.

[0012] Item 1. An adsorption sheet, comprising silica gel and / or a porous metal complex as the porous material, wherein when the pore volume determined by mercury porosimetry is A cc / g and the pore volume determined by N2 adsorption isotherm at a relative pressure p / p0 = 0.4 is B cc / g, the value B / A obtained by dividing B by A is 0.25 or less.

[0013] Item 2. An adsorption sheet, comprising silica gel and / or a porous metal complex as the porous material, wherein when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

[0014] Item 3. The adsorption sheet according to item 1 or 2, containing 40% by mass to 85% by mass of the silica gel and / or porous metal complex.

[0015] Item 4. A corrugated sheet, comprising the adsorption sheet according to item 1 or 2 laminated together, wherein the flat adsorption sheet and the corrugated adsorption sheet are laminated together, and the corrugated sheet has a large number of cells that serve as air passages.

[0016] Item 5. A corrugated laminate obtained by laminating the corrugated sheets according to Item 4.

[0017] Item 6. The number of cells per area of ​​the surface through which air passes is 80 cells / cm 2 More than 135 pieces / cm 2 Item 6. The stepped laminate according to item 5, which is as follows:

[0018] Item 7. A step-processed laminate (as described in item 5 or 6) comprising an adsorbent sheet containing silica gel and / or a porous metal complex as the porous material, wherein when the pore volume determined by mercury porosimetry is A cc / g and the pore volume determined by N2 adsorption isotherm at a relative pressure p / p0 = 0.4 is B cc / g, the value B / A obtained by dividing B by A is 0.25 or less.

[0019] Item 8. A step-processed laminate according to any one of Items 5 to 7, comprising silica gel and / or a porous metal complex as the porous material, wherein when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

[0020] Item 9. An adsorption element comprising the stepped laminate according to any one of items 5 to 8.

[0021] Item 10. A dehumidifier comprising: a rotor; an adsorption zone air supply passage; and a regeneration zone air supply passage, wherein the rotor rotates the adsorption element according to Item 9 around a rotation axis and has an adsorption zone and a regeneration zone along a circumferential direction which is the rotation direction of the rotor, the adsorption zone air supply passage is an adsorption zone air supply passage that supplies air to be treated to the adsorption zone to cause the adsorption element to adsorb moisture in the air, and the regeneration zone air supply passage is a regeneration zone air supply passage that supplies regeneration air to the regeneration zone for desorbing moisture from the adsorption element that has adsorbed moisture.

[0022] The adsorbent sheet of the present disclosure adjusts A (or C): the pore volume of mesopores to macropores (3 nm to 500 μm) (measured by mercury intrusion porosimetry), and B (or D): the pore volume of micropores (less than 3 nm) (measured by N adsorption).

[0023] In the adsorption sheet of the present disclosure, B (or D), which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A (or C) also serve as a driving force for approaching the micropores.

[0024] It is important that the adsorption sheet of the present disclosure has B<<A (or D<<C), and by having B / A (or D / C) be 0.25 or less, gas diffusion within the adsorption sheet can be carried out with high efficiency.

[0025] In the adsorbent sheet of the present disclosure, the range of A (or C) is preferably 1.5 to 3, and more preferably 1.5 to 2.8.

[0026] In the adsorption sheet of the present disclosure, the range of B (or D) is preferably 0.1 to 0.4, and more preferably 0.1 to 0.38.

[0027] By applying the adsorption sheet (corrugated sheet, corrugated laminate, and adsorption element) of the present disclosure to a dehumidifier, the gas diffusion within the adsorption sheet can be improved, and the dehumidification performance can be improved.

[0028] The present disclosure can newly provide an adsorbent sheet, a corrugated sheet, a corrugated laminate, an adsorbent element, and a dehumidifier.

[0029] FIG. 1 is an explanatory diagram illustrating a porous metal complex having open metal sites (coordinatively unsaturated sites). FIG. 2 is an explanatory diagram illustrating a porous metal complex having OH groups in the metal core unit. FIG. 3(A) is a perspective view of a liner-shaped adsorption sheet. FIG. 3(B) is a perspective view of a corrugated adsorption sheet. FIG. 3(C) is a perspective view of an adsorption sheet in which a corrugated adsorption sheet is laminated on a liner-shaped adsorption sheet. FIG. 4(A) is a perspective view showing the procedure for forming an adsorption element. FIG. 4(B) is a perspective view of an adsorption element. FIG. 5 is a schematic diagram of an adsorption / desorption treatment device.

[0030] Embodiments of the adsorbent sheet, the corrugated sheet, the corrugated laminate, the adsorbent element, and the dehumidifier of the present disclosure will be described.

[0031] The embodiments described in this disclosure are intended to provide a better understanding of the gist of the invention, and unless otherwise specified, do not limit the content of the invention.

[0032] In this specification, the terms "comprise" and "contain" encompass the concepts of "comprise," "consist essentially of," and "consist only of." In this specification, when a numerical range is expressed as "A to B," the numerical range means "greater than or equal to A and less than or equal to B."

[0033] <Adsorption sheet> The adsorption sheet of the present disclosure contains silica gel and / or a porous metal complex as a porous material, and when the pore volume determined by mercury porosimetry is A cc / g and the pore volume at a relative pressure p / p0 = 0.4 determined by an N2 adsorption isotherm is B cc / g, the value B / A obtained by dividing B by A is 0.25 or less.

[0034] The adsorption sheet of the present disclosure contains silica gel and / or a porous metal complex as the porous material, and when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

[0035] The adsorbent sheet of the present disclosure contains 40% to 85% by mass of silica gel and / or a porous metal complex.

[0036] The adsorption sheet of the present disclosure adsorbs some of the gases contained in the gas to be treated, such as moisture, carbon dioxide, organic solvents, and malodorous components.

[0037] The adsorption sheet of the present disclosure includes a porous material, and preferably further contains a flocculant, fibers, an organic binder, etc. The porous material is a material for adsorbing a target substance.

[0038] The adsorption sheet is a sheet containing a porous material such as silica gel, zeolite, etc. The adsorption sheet is produced, for example, by a wet papermaking method in which a porous material, fiber, and an organic binder are mixed and paper-made.

[0039] The fibers are the material that forms the framework of the adsorption sheet, and the organic binder is the material that fixes the porous material to the adsorption sheet and improves the strength and flexibility of the adsorption sheet.

[0040] <Porous Material> The adsorbent sheet of the present disclosure contains silica gel and / or a porous metal complex as the porous material, because (1) A (or C): the pore volume (measured by mercury intrusion porosimetry) of mesopores to macropores (3 nm to 500 μm), and B (or D): the pore volume (measured by N adsorption) of micropores (less than 3 nm), are adjusted; (2) B, which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A, in addition, act as a driving force for gas to approach the micropores; and (3) when used in a dehumidifier, the gas diffusion within the adsorbent sheet can be improved, thereby improving dehumidification performance.

[0041] The porous material contained in the adsorption sheet is not particularly limited as long as it has the ability to adsorb the target substance, and can be appropriately selected from known porous materials depending on the target substance. Preferred examples of the porous material include zeolite, silica gel, and porous materials called porous coordination polymers (PCP / metal organic frameworks, MOF).

[0042] (Zeolite) Preferred examples of zeolite include natural zeolite, synthetic zeolite (also called molecular sieve), and artificial zeolite. The zeolite may be selected from the above-mentioned types depending on the purpose, but it is preferable to select synthetic zeolite from the viewpoint of quality and performance stability.

[0043] (Silica gel) Preferred examples of silica gel include type A silica gel, type B silica gel, etc. When the substance to be adsorbed is a polar substance such as water or carbon dioxide, type A silica gel with a small average pore size or type RD silica gel with physical properties similar to type A silica gel are preferred, from the viewpoint of improving the adsorption performance for the substance to be adsorbed.

[0044] From the viewpoint of improving the desorption performance for the substance to be adsorbed, type B silica gel, which has a large average pore diameter, is preferred. In order to achieve both adsorption and desorption performance, type A silica gel or type RD silica gel and type B silica gel may be mixed in any ratio depending on the desired performance.

[0045] (Porous metal complex, Figures 1 and 2) Porous metal complexes are porous materials that are self-assembled by combining metal ions, which can take various coordination forms, with organic ligands that have two or more coordination sites. In porous metal complexes, a framework structure is constructed by the organic ligands bridging the metal ions that serve as nodes, and the pores within this framework act as spaces that capture the substances to be adsorbed.

[0046] Compared to inorganic porous materials such as silica gel and zeolite, porous metal complexes have characteristics such as a high specific surface area, a sharp pore distribution, and high structural designability, and therefore have the advantages of a fast adsorption rate for the substance to be adsorbed and a large amount of the substance to be adsorbed that can be adsorbed.

[0047] Porous metal complexes adsorb and desorb substances using weak bonding forces such as coordination interactions and hydrogen bonds. This means that the heat of adsorption generated when adsorbing the substance is small, and the adsorbed substance can be desorbed even when the temperature of the regeneration gas is low, which has the advantage of requiring less energy for regeneration.

[0048] By using a porous metal complex as the porous material, the adsorption sheet can effectively adsorb the target substance in the gas to be treated.

[0049] The metal ions constituting the porous metal complex are not particularly limited, and examples thereof include titanium ions, iron ions, cobalt ions, nickel ions, copper ions, zinc ions, aluminum ions, zirconium ions, etc. Among these, the metal ions constituting the porous metal complex are preferably titanium ions, iron ions, manganese ions, copper ions, zinc ions, aluminum ions, and zirconium ions, which are less toxic in consideration of environmental pollution.

[0050] Examples of compounds having an organic ligand include the following compounds.

[0051] Dicarboxylic acids such as terephthalic acid, isophthalic acid, 2-aminoterephthalic acid, 2,5-diaminoterephthalic acid, 2,5-dihydroxyterephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 3,3'-biphenyldicarboxylic acid, fumaric acid, 1H-pyrazole-3,5-dicarboxylic acid, and 2,5-furandicarboxylic acid.

[0052] Tricarboxylic acids such as trimesic acid.

[0053] Tetracarboxylic acids such as azobenzene-3,3'-5,5'-tetracarboxylic acid.

[0054] Imidazoles such as 2-methylimidazole.

[0055] Specific examples of porous metal complexes: Porous metal complex composed of aluminum ions and 1H-pyrazole-3,5-dicarboxylic acid (MOF303) Porous metal complex composed of aluminum ions and 2,5-furandicarboxylic acid (MIL160) Porous metal complex composed of iron ions and azobenzene-3,3'-5,5'-tetracarboxylic acid (PCN250) Porous metal complex composed of iron ions and trimesic acid (MIL100) Porous metal complexes composed of iron ions and terephthalic acid (MIL53, MIL101) Porous metal complex composed of zirconium ions and fumaric acid (MOF801) Porous metal complex composed of zirconium ions and terephthalic acid (UiO66) Porous metal complex composed of zirconium ions and 2-aminoterephthalic acid (UiO66-NH2) Porous metal complex composed of titanium ions and terephthalic acid (MIL125) Porous metal complex composed of titanium ions and 2-aminoterephthalic acid (MIL125-NH2) Porous metal complex composed of nickel and 2,5-dihydroterephthalic acid (MOF74-Ni) Porous metal complex composed of magnesium and 2,5-dihydroterephthalic acid (MOF74-Mg) Porous metal complex composed of chromium and terephthalic acid (MIL101)

[0056] These porous metal complexes, even if they are the same porous metal complexes, have different BET specific surface areas depending on the synthesis method and purity.

[0057] When the substance to be adsorbed is a polar substance such as water or carbon dioxide, the porous metal complex preferably has adsorption sites, from the viewpoint of improving the adsorption performance for the substance to be adsorbed. Examples of adsorption sites include open metal sites (coordinatively unsaturated sites). Open metal sites exhibit high adsorption activity. Therefore, porous metal complexes having open metal sites have a very fast adsorption rate for the substance to be adsorbed in the gas to be treated, and exhibit high adsorption performance.

[0058] One embodiment of an open metal site is, for example, an embodiment in which the metal ion is coordinatively unsaturated and has at least one vacant site in its coordination state, that is, a coordinatively unsaturated site.

[0059] As shown in Figure 1, in porous metal complexes with coordinatively unsaturated sites, the ligands of the metal ions (Fe ions in Figure 1) are unsaturated, and the metal ions have one or more vacant ligands (vacant sites). The target substance is adsorbed onto these vacant sites. Porous metal complexes with coordinatively unsaturated sites exhibit high adsorption performance.

[0060] Specific examples of porous metal complexes having coordinatively unsaturated sites include PCN250, MOF74-Ni, MOF74-Mg, and MIL101. Among these, PCN250 is preferred because it has a fast adsorption / desorption rate and uses a metal that is water-resistant and has low toxicity.

[0061] In addition to porous metal complexes with open metal sites, porous metal complexes that exhibit high adsorption performance, i.e., porous metal complexes with adsorption sites, include porous metal complexes that have OH groups (hydroxy groups) near the metal.

[0062] Porous metal complexes with OH groups near the metal have OH groups in the metal core unit, as shown in Figure 2. When a porous metal complex has OH groups in the metal core unit, it exhibits excellent adsorption activity for the target substances. Therefore, porous metal complexes with OH groups near the metal have an extremely fast adsorption and desorption rate for the target substances in the gas to be treated, demonstrating high adsorption performance.

[0063] The metal core unit refers to a metal cluster that constitutes a porous metal complex represented by MxOyHz (x and y are integers other than 0, z is an integer including 0). Some of the oxygen atoms in the metal core unit MxOyHz are carboxyl group oxygen atoms of organic ligands, and the metal core unit forms a framework by sharing oxygen atoms with the organic ligands.

[0064] Specific examples of porous metal complexes having OH groups in the vicinity of the metal include MOF801 and MOF303.

[0065] The porous material can be in various forms, such as powder, granules, fibers, etc. The adsorption sheet contains a large number of powder or granular porous materials.

[0066] (Physical Properties of Porous Material) The size of the porous material is not particularly limited, but is preferably 0.1 μm or more, more preferably 0.5 μm or more, and more preferably 1 μm or more. On the other hand, the size of the porous material is not particularly limited, but is preferably 200 μm or less, more preferably 150 μm or less, more preferably 100 μm or less, and more preferably 80 μm or less.

[0067] When the size of the porous material is 0.1 μm or more and 200 μm or less, the gas to be treated can be brought into good contact with the porous material, improving the adsorption performance of the porous material. Furthermore, when the size of the porous material is 0.1 μm or more and 200 μm or less, the pressure loss when the gas to be treated comes into contact with the porous material can be reduced, the porous material can be supported on the adsorption sheet at a high density, and the detachment of the porous material from the adsorption sheet can be reduced.

[0068] The size of the porous material is measured by the D50 value of a laser diffraction particle size distribution analyzer or the average particle diameter measured by a scanning electron microscope.

[0069] The pore structure of the porous material is not particularly limited. When the porous material is a porous metal complex, the pore structure of the porous metal complex may be one-dimensional or three-dimensional. From the viewpoint of a high adsorption rate of the substance to be adsorbed and ease of adsorption of the substance to be adsorbed, the pores of the porous metal complex are preferably one-dimensional. Specific examples of porous metal complexes having one-dimensional pores include PCN250, MOF303, and MOF74.

[0070] When a porous metal complex has three-dimensional pores but no open metal sites, it is preferable that the crystallite size of the porous metal complex be small so that the target substance can be easily adsorbed all the way to the inside of the pores. A specific example of a porous metal complex that has three-dimensional pores but no open metal sites is MOF801.

[0071] The pore size of the porous material is not particularly limited. When the porous material is a porous metal complex and the substance to be adsorbed is a polar substance with a relatively small size, such as water or carbon dioxide, the pore size of the porous metal complex is preferably 3.0 Å or more, more preferably 3.5 Å or more, from the viewpoint of improving the adsorption performance for the substance to be adsorbed. On the other hand, the pore size of the porous metal complex is preferably 10 Å or less, more preferably 8 Å or less.

[0072] When the pore diameter of the porous metal complex is 3.0 Å or more and 10 Å or less, the substance to be adsorbed can be well adsorbed into the pores, improving the adsorption performance of the porous metal complex.Furthermore, when the pore diameter of the porous metal complex is 3.0 Å or more and 10 Å or less, the adsorbed substance to be adsorbed can be easily desorbed from the porous metal complex during regeneration of the porous metal complex.

[0073] When priority is given to increasing the desorption rate of the porous metal complex and improving the adsorption performance of the porous metal complex, the pore diameter of the porous metal complex is preferably greater than 10 Å.

[0074] The pore size of the porous metal complex can be obtained by measuring the cage diameter or window diameter of the pores using X-ray structural analysis.

[0075] When the porous material is silica gel, the pore size of the silica gel is not particularly limited. When the substance to be adsorbed is a polar substance such as water or carbon dioxide, the pore size of the silica gel is preferably an average pore size of 30 Å or less from the viewpoint of improving the adsorption performance for the substance to be adsorbed. On the other hand, from the viewpoint of improving the desorption performance for the substance to be adsorbed, the pore size of the silica gel is preferably an average pore size of 70 Å or less. In order to achieve both adsorption performance and desorption performance, multiple types of silica gel with average pore sizes in the range of 10 Å to 70 Å may be mixed and used in any ratio depending on the desired performance.

[0076] When the porous material is zeolite, the pore size of the zeolite is largely determined by the crystal structure, so the crystal structure of the zeolite may be selected according to the purpose, and two or more types of zeolite may be used in combination.

[0077] The specific surface area of ​​the porous material measured by the BET method (BET specific surface area) is not particularly limited. When the porous material is a porous metal complex, the specific surface area of ​​the porous metal complex measured by the BET method (BET specific surface area) is preferably 200 m 2 / g or more, more preferably 300m 2 / g or more, and more preferably 500m 2 / g or more, more preferably 900m 2 / g or more, and more preferably 1,000m 2 / g or more, and more preferably 1,500m 2 / g or more, and more preferably 1,800m 2 / g or more.

[0078] The BET specific surface area of ​​the porous metal complex is preferably 6,000 m 2 / g or less, and more preferably 2,500m 2 / g or less, and more preferably 2,000m 2 / g or less.

[0079] The specific surface area of ​​the porous metal complex is 200m 2 / g or more 6,000m 2 When the specific surface area of ​​the porous metal complex is 200 m / g or less, the substance to be adsorbed can be adsorbed well into the pores, and the adsorption performance of the porous metal complex can be improved. 2 / g or more 6,000m 2 / g or less, a porous metal complex can be easily produced. 2 When the pore size is 1 / g or less, the strength of the porous metal complex can be sufficiently ensured.

[0080] When the porous material is silica gel, the specific surface area of ​​the silica gel measured by the BET method is preferably 200 m 2 / g or more, more preferably 300m 2 / g or more, more preferably 400m 2 / g or more.

[0081] When the porous material is zeolite, the specific surface area of ​​the zeolite measured by the BET method is preferably 200 m 2 / g or more 900m 2 / g or less.

[0082] The bulk density of the porous material is not particularly limited, but is preferably 0.2 g / cc or more, more preferably 0.23 g / cc or more. When the bulk density of the porous material is 0.2 g / cc or more, the voids between the multiple porous materials can be made small, and the porous materials can be supported on the adsorption sheet at a high density. When the bulk density of the porous material is 0.2 g / cc or more, the adsorption sheet can effectively adsorb the target substance in the gas to be treated.

[0083] The bulk density of a porous material is measured by dividing the volume of a container of known volume by the weight of the porous material when the porous material is filled up to the sill.

[0084] When the porous material is a porous metal complex, the water adsorption rate of the porous metal complex at 25°C and a relative pressure of 0.5 is not particularly limited, but is preferably 30% by mass or more, more preferably 35% by mass or more, and more preferably 40% by mass or more.

[0085] The pressure when the progress of adsorption appears to have stopped under a constant pressure (number of adsorbed molecules = number of desorbed molecules) is called the adsorption equilibrium pressure, and the relative pressure is the ratio of the adsorption equilibrium pressure to the saturated vapor pressure.

[0086] By incorporating a porous metal complex with a moisture adsorption rate of 30% by mass or more at 25°C and a relative pressure of 0.5, the adsorbent sheet can retain a large amount of the target substance and is endowed with high flexibility during processing. Furthermore, because the porous metal complex imparts sufficient flexibility to the adsorbent sheet, the amount of organic binder that is conventionally contained in adsorbent sheets to impart flexibility can be reduced. As a result, the rate at which side chains of the organic binder adsorb into the pores of the porous material and block the pores can be reduced, improving the adsorption performance of the porous material.

[0087] The water adsorption rate of a porous metal complex at 25°C and a relative pressure of 0.5 was measured by taking approximately 100 mg of the porous metal complex (before treatment with water or an organic solvent), vacuum drying it at 120°C for 12 hours, and weighing it. Then, using a high-precision gas / vapor adsorption analyzer (BELSORP-max, manufactured by BEL Japan), the amount of water vapor adsorption at 25°C was measured at 40 points while gradually increasing the relative pressure in the range of 0.02 to 0.95, and an adsorption isotherm was created.

[0088] At this time, the target relative pressure is set to 0.001, 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9, and the adsorption amount increase / decrease tolerance is set to 30 cm for relative pressures of 0 to 0.3. 2 / g, 50cm at relative pressures of 0.3 to 0.5 2 / g, relative pressure 0.5 - 30cm 2 / g, and an adsorption isotherm is created. Then, the moisture adsorption rate [%] is calculated using the following formula a from the amount of moisture adsorbed [g] per 1 g of porous metal complex at a relative pressure of 0.5. Moisture adsorption rate = amount of moisture adsorbed [g] per 1 g of porous metal complex x 100 (formula a)

[0089] The content of the porous material in the adsorption sheet is not particularly limited, but is preferably 40% by mass or more, more preferably 50% by mass or more. On the other hand, the content of the porous material is not particularly limited, but is preferably 85% by mass or less, more preferably 83% by mass or less. When the content of the porous material is 40% by mass or more and 85% by mass or less, the adsorption sheet can support a high content of the porous material, so that the adsorption sheet can effectively adsorb the target substance to be adsorbed in the gas to be treated. When the content of the porous material is 40% by mass or more and 85% by mass or less, it is possible to reduce the detachment of the porous material from the adsorption sheet and to ensure sufficient strength of the adsorption sheet.

[0090] The porous material may contain one or more of the above-mentioned silica gel, zeolite, and porous metal complex. The porous material may also contain a porous material other than the above-mentioned silica gel, zeolite, and porous metal complex, such as an organic polymer porous material such as activated carbon, activated alumina, aluminophosphate, silicoaluminophosphate, or styrene-divinylbenzene copolymer.

[0091] (Porous Material Content) The adsorbent sheet of the present disclosure contains 40% by mass to 85% by mass, more preferably 45% by mass to 83% by mass, even more preferably 50% by mass to 83% by mass, and particularly preferably 55% by mass to 83% by mass of silica gel and / or a porous metal complex, because (1) A: the pore volume (measured by mercury intrusion porosimetry) of mesopores to macropores (3 nm to 500 μm) and B: the pore volume (measured by N2 adsorption) of micropores (less than 3 nm) are adjusted, (2) B, which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A, which acts as a driving force for approaching the micropores, and (3) when used in a dehumidifier, the gas diffusion within the adsorbent sheet can be improved, and the dehumidifying performance can be improved.

[0092] <Fibers> The fibers constituting the adsorption sheet are not particularly limited, and for example, natural fibers, synthetic fibers, regenerated fibers, semi-synthetic fibers, inorganic fibers, etc. may be used.

[0093] Specific examples of natural fibers include cotton, hemp, and pulp.

[0094] Specific examples of synthetic fibers include aramid fibers, meta-aramid fibers, polybenzimidazole fibers, polybenzoxazole fibers, polyimide fibers, polyamideimide fibers, polyether ketone fibers, polyethylene terephthalate fibers, and nylon fibers.

[0095] Specific examples of regenerated fibers include rayon, polynosic, cupra, etc. Specific examples of semi-synthetic fibers include acetate fiber, triacetate fiber, etc.

[0096] Specific examples of inorganic fibers include glass fibers, ceramic fibers, and rock wool fibers.

[0097] The fibers constituting the adsorption sheet may be a combination of two or more of the above-mentioned fibers.

[0098] The fibers constituting the adsorption sheet preferably contain non-fibrillated fibers and fibrillated fibers.

[0099] The adsorbent sheet contains non-fibrillated fibers, so that when the adsorbent sheet is subjected to, for example, a corrugated process, the adsorbent sheet can maintain its corrugated shape.

[0100] The inclusion of fibrillated fibers in the adsorption sheet allows the adsorption sheet to efficiently support the porous material. The inclusion of fibrillated fibers in the adsorption sheet allows the amount of organic binder contained in the adsorption sheet to fix the porous material to the adsorption sheet to be reduced, preventing the pores of the porous material from being blocked by the organic binder, and improving the adsorption performance of the porous material.

[0101] The fiber diameter of the non-fibrillated fibers is not particularly limited, but is preferably 5 μm or more and 30 μm or less.

[0102] The fiber length of the non-fibrillated fibers is not particularly limited, but is preferably 1 mm or more, more preferably 2 mm or more. The fiber length of the non-fibrillated fibers is not particularly limited, but is preferably 10 mm or less, more preferably 8 mm or less.

[0103] When the non-fibrillated fibers have a fiber diameter of 5 μm or more and a fiber length of 1 mm or more, the strength of the adsorbent sheet can be sufficiently ensured, and when the adsorbent sheet is subjected to, for example, a corrugated shape, the adsorbent sheet can maintain that shape. When the non-fibrillated fibers have a fiber diameter of 30 μm or less and a fiber length of 10 mm or less, the adsorbent sheet has appropriate flexibility, and can easily be subjected to, for example, a corrugated process. The non-fibrillated fibers may be a mixture of fibers of different diameters and lengths.

[0104] The fibrillated fibers are, for example, fibers obtained by fibrillating the non-fibrillated fibers described above. The fibrillation method is not particularly limited, and any conventionally known method can be used, such as a beating method using a beating machine such as a beater or a refiner.

[0105] The fibrillated fibers are not particularly limited, but when the Canadian Standard Freeness (CSF) is measured in accordance with JIS P 8121-2, the value is preferably 50 mL or more and less than 800 mL.

[0106] The total content of non-fibrillated fibers and fibrillated fibers in the adsorbent sheet is not particularly limited, but is preferably 5% by mass or more, more preferably 10% by mass or more, while the total content of non-fibrillated fibers and fibrillated fibers in the adsorbent sheet is not particularly limited, but is preferably 45% by mass or less.

[0107] When the total content of non-fibrillated fibers and fibrillated fibers in the adsorbent sheet is 5% by mass or more and 45% by mass or less, a sufficient amount of porous material can be supported on the adsorbent sheet, and the detachment of the porous metal complex from the adsorbent sheet can be reduced.When the total content of non-fibrillated fibers and fibrillated fibers in the adsorbent sheet is 5% by mass or more and 45% by mass or less, the strength of the adsorbent sheet can be sufficiently ensured.

[0108] <Organic Binder> The organic binder contained in the adsorption sheet is not particularly limited as long as it can fix the porous material to the adsorption sheet. Examples of the organic binder that can be used include polyvinyl alcohol (PVA)-based polymers, polyacrylonitrile-based polymers, polyethylene-based polymers, polyester-based polymers, and polyphenylene ether-based polymers. A preferred example of the organic binder is polyvinyl alcohol (PVA)-based polymers from the viewpoint of ease of handling.

[0109] The form of the organic binder is not particularly limited, but it is preferable to use a fibrous organic binder, since this allows the adsorption sheet to be easily produced.

[0110] The content of the organic binder in the adsorption sheet is not particularly limited, but is preferably 3% by mass or more, more preferably 4% by mass or more, while the content of the organic binder in the adsorption sheet is not particularly limited, but is preferably 20% by mass or less, more preferably 18% by mass or less.

[0111] When the content of the organic binder in the adsorption sheet is 3% by mass or more and 20% by mass or less, the supportability and flexibility of the porous material in the adsorption sheet can be sufficiently ensured.When the content of the organic binder in the adsorption sheet is 3% by mass or more and 20% by mass or less, the rate at which the side chains of the organic binder are adsorbed into the pores of the porous material and block the pores can be reduced, and the adsorption performance of the porous material can be improved.

[0112] The organic binder functions to improve the flexibility of the adsorption sheet. Even if the content of the organic binder in the adsorption sheet is small, the adsorption sheet contains fibrillated fibers, which allows the adsorption sheet to exhibit good support for the porous material, and the high moisture adsorption rate of the porous material allows the adsorption sheet to exhibit flexibility. This not only allows the content of the organic binder in the adsorption sheet to be reduced, but also prevents the organic binder from blocking the pores of the porous material, improving the adsorption performance of the porous material.

[0113] The water dissolution temperature of the organic binder is not particularly limited, but is preferably 65° C. or higher, and more preferably 70° C. or higher. On the other hand, the water dissolution temperature of the organic binder is not particularly limited, but is preferably 100° C. or lower.

[0114] When the dissolution temperature of the organic binder in water is 65°C or higher and 100°C or lower, the rate at which the side chains of the organic binder adsorb to the pores of the porous material and block the pores can be reduced, improving the adsorption performance of the porous material. Furthermore, when the dissolution temperature of the organic binder in water is 65°C or higher and 100°C or lower, the adhesive strength of the organic binder can be well exhibited, allowing the porous material to be effectively supported on the adsorption sheet by the organic binder.

[0115] The dissolution temperature of the organic binder in water can be measured by a conventionally known method. For example, 100 mL of pure water is placed in a beaker, stirred, and heated in an oil bath until the water temperature reaches 50°C. 0.5 g of organic binder is added to the heated water, and the water temperature is increased at a rate of 2°C / min. The temperature is measured when the organic binder begins to dissolve and the water becomes translucent.

[0116] <Cationic Surfactant> In addition to the porous material, fibers, and organic binder described above, the adsorbent sheet contains a cationic surfactant as a water repellent agent for the purpose of imparting water repellency to the adsorbent sheet.

[0117] If the adsorbent sheet has water repellency, when an adsorbent sheet is used to manufacture an adsorbent element, for example, with a honeycomb structure, even if a silica-based inorganic adhesive is attached to the adsorbent sheet, the silica-based inorganic adhesive can be prevented from seeping into the adsorbent sheet before hardening. Because the adhesive is less likely to seep into the adsorbent sheet before hardening, the adsorbent sheets can be bonded together well, making it easier to manufacture the adsorbent element. If the adsorbent sheet has water repellency, the adhesive can be prevented from seeping into the adsorbent sheet and clogging the pores of the porous material, thereby preventing a decrease in the adsorption performance of the porous material in the adsorbent element.

[0118] The cationic surfactant is not particularly limited, and examples thereof include amine salt types and quaternary ammonium salt types. Examples of amine salt types include aliphatic amidoamines. Examples of quaternary ammonium salt types include monoalkyl types, monoalkyl ether types, dialkyl types, dialkyl ester types, and benzalkonium types.

[0119] The cationic surfactant preferably has a long alkyl chain and an amide moiety in its primary structure. The long alkyl chain and the amide moiety may exist in a single compound or as separate compounds. A preferred example of a cationic surfactant having a long alkyl chain and an amide moiety is "Santol KL-2" manufactured by Nicca Chemical Co., Ltd.

[0120] <Cationic surfactants having a long alkyl chain and an amide moiety> Cationic surfactants having a long alkyl chain and an amide moiety have a partial structure of the following chemical formula (R 1 =C, R 2 , R 3 = C or H), and R 1 contains an alkyl chain having 5 to 30 carbon atoms. 1 The alkyl chain and CO-NR in the chemical formula 2 R3 The amide moieties may be present within a single compound or as separate compounds.

[0121]

[0122] The adsorption sheet contains a cationic surfactant having a long alkyl chain and an amide moiety, which allows the adsorption sheet to exhibit good water repellency. The cationic surfactant containing an amide moiety improves the dispersibility of the cationic surfactant in solvents such as water and its adsorption to fibers during the manufacturing process of the adsorption sheet, thereby enabling the cationic surfactant to be uniformly supported on the adsorption sheet.

[0123] The cationic surfactant having a long alkyl chain and an amide moiety is added as a water repellent to the raw materials, porous material, fibers and organic binder, when producing an adsorbent sheet by a wet papermaking method.

[0124] Whether or not an adsorbent sheet or an adsorbent element manufactured using the adsorbent sheet contains a cationic surfactant with a long alkyl chain and an amide moiety can be confirmed by pyrolysis gas chromatography mass spectrometry (pyrolysis GC-MS). Specifically, 1 mL of chloroform is added to 0.1 g of sheet material cut from the adsorbent sheet or adsorbent element, and ultrasonic extraction is performed at room temperature for 30 minutes. 0.5 g of the extract obtained by ultrasonic extraction is then placed in a sample cup for pyrolysis GC-MS, and after the chloroform is removed from the extract, pyrolysis GC-MS is performed.

[0125] The conditions for pyrolysis GC-MS are as follows: The gas components generated by the pyrolysis reaction of the sample are subjected to gas chromatography mass spectrometry (GC-MS), and the detection of fragment ion peaks at m / z = 59 and 72, which are characteristic of compounds with an amide moiety containing a long alkyl chain, confirms that the adsorption sheet or adsorption element contains a cationic surfactant with a long alkyl chain and an amide moiety.

[0126] [Conditions for pyrolysis GC-MS] Instrument: PY-2020iD (Frontier LAB) / QP-2010Plus (Shimadzu Corporation) Sample heating conditions: 550°C x 0.5 min Column: Ultra ALLOY-5 (MS / HT) (length 30 m, inner diameter 0.25 mm, film thickness 0.25 μm) Column temperature: 50°C (2 min) - 20°C / min - 320°C (10 min) Inlet pressure: 80 kPa Inlet temperature: 320°C Split ratio: 30 Ion source: EI method Ion source temperature: 250°C Ionization voltage: 70 eV Interface temperature: 320°C MS measurement mode: SIM and / or SCAN Measurement ions: m / z 29-550 in SCAN mode, m / z 59, 72 in SIM mode

[0127] <Method for Producing Adsorbent Sheet> The method for producing the adsorbent sheet is not particularly limited, but a preferred example is a wet papermaking method.

[0128] (Wet Papermaking Method) When producing the adsorbent sheet of the present disclosure, the porosity is adjusted, and the fibers and adsorbent are kept constantly dispersed, and preferably an appropriate amount of flocculant is added (wet papermaking method).

[0129] (1) Preparation of Dispersed Slurry When producing an adsorbent sheet by a wet papermaking method, first, the porous material, fibers, and organic binder are dispersed and mixed in a solvent such as water or an organic solvent at a predetermined blending ratio.

[0130] <Flocculant> When producing an adsorption sheet, a polymer flocculant may be added as an additive in addition to the raw materials of the porous material, fiber and organic binder, and the water repellent agent.

[0131] The polymer flocculant is a chemical used to aggregate and precipitate the porous material, fibers, and organic binder dispersed in a solvent when producing an adsorbent sheet.

[0132] As the polymer flocculant, a conventionally known flocculant can be used. As the polymer flocculant, a cationic polymer flocculant, an amphoteric polymer flocculant, an anionic / nonionic polymer flocculant, or the like is preferably used. More preferably, a cationic polymer flocculant is used. As the organic polymer flocculant, for example, Tetsuflock (registered trademark) manufactured by Nittetsu Mining Co., Ltd., or the like is used.

[0133] The suspension is thoroughly stirred to maintain the dispersion of the porous material, fibers, organic binder, etc., and a flocculant is added dropwise at a rate of approximately 10 ml / g relative to the total material, followed by the wet papermaking method to prepare an adsorption sheet.

[0134] (2) Sheet Forming Step Next, the obtained dispersion slurry is made into a sheet using a paper machine.

[0135] In the sheet-forming step, it is preferable to mix the porous material with other materials in a state where the solvent molecules have penetrated into the pores of the porous material.

[0136] If the porous material does not have solvent molecules in the pores, the organic binder that constitutes the adsorption sheet may be trapped in the pores. In this case, it is difficult to remove the organic binder trapped in the pores of the porous material after forming the sheet, and the adsorption performance of the adsorption sheet may be reduced.

[0137] By trapping the solvent molecules within the pores of the porous material, the organic binder is prevented from penetrating and being trapped in the pores of the porous material during the sheet-forming process, and after the sheet-forming process, the solvent molecules are removed from the pores by a desolvation process, thereby ensuring the adsorption performance of the adsorption sheet.

[0138] When an adsorption sheet is manufactured with solvent molecules trapped in the pores of a porous material, if the solvent molecules remain in the pores of the porous material, the porous material will not exhibit sufficient adsorption performance.

[0139] The solvent removal treatment is performed on the adsorption sheet so that the adsorption performance of the porous material can be fully exhibited.

[0140] The conditions for the solvent removal treatment are not particularly limited. For example, the temperature for the solvent removal treatment is not particularly limited, but is preferably 50° C. or higher, more preferably 80° C. or higher. The temperature for the solvent removal treatment is not particularly limited, but is preferably 300° C. or lower, more preferably 200° C. or lower.

[0141] When the temperature of the solvent removal treatment is 50° C. or higher and 300° C. or lower, there is little risk of the pore structure of the porous material being destroyed, and the solvent can be efficiently removed from the pores of the porous material.

[0142] The solvent removal treatment is preferably carried out under reduced pressure. This allows the solvent to be removed from the pores of the porous material more efficiently. The pressure for the solvent removal treatment is not particularly limited and may be adjusted appropriately depending on the physical properties and amount of the porous material. 3 Pa or less, more preferably 10 -1 The pressure for the solvent removal treatment is not particularly limited, but is preferably 10 Pa or less. -5 Pa or more.

[0143] The time for the solvent removal treatment is not particularly limited, but is preferably 20 seconds or more, more preferably 30 seconds or more, and is not particularly limited, but is preferably 5 minutes or less, more preferably 3 minutes or less, and more preferably 1 minute or less.

[0144] The most preferable conditions for the solvent removal treatment are a temperature of 80° C. or higher and 200° C. or lower under vacuum conditions, and a treatment time of 20 seconds or higher and 5 minutes or lower.

[0145] (3) Dehydration and Drying Step The obtained sheet-like material is then dehydrated and dried to obtain an adsorption sheet.

[0146] The dehydration and drying methods are not particularly limited, and conventionally known methods can be used. Examples of dehydration methods include a method of pressurizing and dehydrating the sheet by passing it between a pair of rolls, and a method of lifting an adsorption sheet onto a net and allowing the sheet to drop by its own weight. Examples of drying methods include sun drying and a method of blowing hot air onto the dehydrated sheet.

[0147] <Shape and properties of adsorption sheet, Figure 3(A)> As shown in Figure 3(A), the adsorption sheet can be used in a liner form (flat plate form), but it can also be used in the desired shape by applying pleating, honeycomb (step) processing, corrugation processing, etc. as appropriate.

[0148] The flexibility of the adsorption sheet is not particularly limited, but is preferably 5% m / g or more, where the tensile elongation index is used as an indicator of flexibility. If the tensile elongation index of the adsorption sheet is 5% m / g or more, the adsorption sheet has good processability, and when the adsorption sheet is used to manufacture an adsorption element having a honeycomb structure, for example, cracks can be suppressed from occurring in the adsorption sheet even if the adsorption sheet is corrugated.

[0149] The tensile elongation index of the adsorption sheet was measured by drying a 15 mm x 100 mm sample piece cut from the adsorption sheet at 120 °C for 1 hour and measuring its weight. The dried sample piece was then left to stand in an atmosphere of 25 °C and 75% RH for 1 hour, and the maximum point elongation [%] was measured using a tensile / compression tester (TENSILON RTG-1310, manufactured by A&D). The chuck distance was 50 mm and the tensile speed was 15 mm / min. Based on the obtained data, the tensile elongation index [% m / g] was calculated using the following formula (b):

[0150] Specific tensile elongation = Maximum point elongation [%] / Sample width [m] / Basis weight of adsorption sheet [g / m 2 ] (Formula b)

[0151] The thickness of the adsorption sheet is not particularly limited, but is preferably 0.1 mm or more. The thickness of the adsorption sheet is preferably 0.9 mm or less, and more preferably 0.7 mm or less. If the thickness of the adsorption sheet is 0.1 mm or more and 0.9 mm or less, the strength of the adsorption sheet can be sufficiently ensured when the adsorption sheet is processed to manufacture an adsorption element, and an increase in pressure loss in the adsorption element manufactured by processing the adsorption sheet can be suppressed.

[0152] The basis weight of the adsorption sheet is not particularly limited, but is preferably 25 g / m 2 More preferably, it is 40 g / m or more. 2 The basis weight of the adsorption sheet is preferably 200 g / m 2and preferably 150 g / m 2 The following is the result.

[0153] The basis weight of the adsorption sheet is 25 g / m 2 More than 200g / m 2 If the basis weight of the adsorption sheet is 25 g / m or less, the thickness of the adsorption sheet can be ensured and a decrease in strength can be suppressed, making it easy to process the adsorption sheet to manufacture an adsorption element. 2 More than 200g / m 2 If the thickness is less than this, the thickness of the adsorption sheet can be prevented from becoming too large, and therefore an increase in pressure loss in the adsorption element manufactured by processing the adsorption sheet can be prevented.

[0154] <Pore volume determined by mercury porosimetry: A (or C) Pore volume determined by N2 adsorption isotherm at a relative pressure of p / p0 = 0.4: B (or D)>

[0155] (Measurement of pore volume obtained by mercury intrusion porosimetry) The sample was cut into a size of approximately 10 mm x 20 mm and then vacuum dried at 150°C for 24 hours. The porosity was measured using an AutoPoreIV 9520 manufactured by Micromeritics. The pore measurement range was approximately 3 nm to 500 μm.

[0156] The pore volume of the adsorption sheet A (mesopores to macropores, 3 nm to 500 μm) is measured using the mercury intrusion method.

[0157] (Pore volume B at relative pressure p / p0 = 0.4 obtained from N2 adsorption isotherm) 50 mg of a sample is collected, dried in vacuum at 150°C overnight, and then weighed.

[0158] Using a high-precision gas / vapor adsorption analyzer (BELSORP-maxII, manufactured by MicrotracBEL), the adsorption amount of nitrogen gas at the boiling point of liquid nitrogen (-195.8°C) was measured at a relative pressure of 3.0 x 10 -8 Measurements were taken at 80 points while gradually increasing the pH in the range of 0.05 to 0.99, and an adsorption isotherm was created.

[0159] The analysis software (BELMaster Version 7.3.2.0) attached to the device was used to calculate the pore volume [cm by the BET method, with the relative pressure set at p / p0 = 0.4, which corresponds to approximately 3 nm.3 / g].

[0160] The pore volume of the adsorption sheet B: micropores (less than 3 nm) is measured using the N2 adsorption isotherm.

[0161] The adsorbent sheet of the present disclosure (1) adjusts A: the pore volume (measured by mercury porosimetry) of mesopores to macropores (3 nm to 500 μm), and B: the pore volume (measured by N2 adsorption) of micropores (less than 3 nm); (2) B, which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A, serve as the driving force for approaching the micropores; and (3) when used in a dehumidifier, the gas diffusibility within the adsorbent sheet can be improved, thereby improving dehumidification performance. Therefore, when the pore volume determined by mercury porosimetry is A cc / g and the pore volume at a relative pressure p / p0 = 0.4 determined from the N2 adsorption isotherm is B cc / g, the value B / A obtained by dividing B by A is preferably 0.25 or less, more preferably 0.23 or less, even more preferably 0.2 or less, and particularly preferably 0.18 or less.

[0162] The adsorbent sheet of the present disclosure (1) adjusts A: the pore volume (measured by mercury intrusion) of mesopores to macropores (3 nm to 500 μm), and B: the pore volume (measured by N2 adsorption) of micropores (less than 3 nm); (2) B, which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A serve as the driving force for approaching the micropores; and (3) when applied to a dehumidifier, the gas diffusion within the adsorbent sheet can be improved, and the dehumidification performance can be improved. Therefore, when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is preferably 0.25 or less, more preferably 0.23 or less, even more preferably 0.2 or less, and particularly preferably 0.18 or less.

[0163] It is important that the adsorption sheet of the present disclosure has B<<A (or D<<C), and by having B / A (or D / C) be 0.25 or less, gas diffusion within the adsorption sheet can be carried out with high efficiency.

[0164] In the adsorbent sheet of the present disclosure, the range of A (or C) is preferably 1.5 to 3, and more preferably 1.5 to 2.8.

[0165] In the adsorption sheet of the present disclosure, the range of B (or D) is preferably 0.1 to 0.4, and more preferably 0.1 to 0.38.

[0166] <Corrugated sheet, Figures 3 (B) and (C)> The corrugated sheet of the present disclosure is formed by laminating the adsorption sheet of the present disclosure, and has a large number of cells that serve as air passages by laminating the flat adsorption sheet with the corrugated adsorption sheet.

[0167] The corrugated sheet of the present disclosure is formed by laminating the suction sheet of the present disclosure, and has a large number of cells that serve as air passages, with the flat suction sheet and the corrugated suction sheet (the suction sheet processed into a corrugated shape) being laminated together.

[0168] When processing the adsorbent sheet into a pleated, honeycomb, corrugated, or other shape, flexibility may be imparted to the adsorbent sheet by allowing the porous material to absorb sufficient moisture so that the adsorbent sheet can be easily folded.The adsorbent sheet may also be processed in a semi-dry state where it is completely dry, and then completely dried after processing.

[0169] FIG. 3(B) shows an example of a processed suction sheet, ie, a corrugated suction sheet 1B (a corrugated suction sheet).

[0170] Figure 3(C) shows a corrugated sheet (C) in which the corrugated adsorption sheet 1B shown in Figure 3(B) is laminated on the liner-shaped adsorption sheet 1A shown in Figure 3(A). The corrugated sheet (C) is produced by bonding multiple bottom portions 10 of the corrugated adsorption sheet (wave-shaped adsorption sheet) 1B to the surface 11 of the liner-shaped adsorption sheet 1A using adhesive 12.

[0171] Although there are no particular limitations on the adhesive 12, a silica-based inorganic adhesive is preferably used from the viewpoint of heat resistance. Specific examples of silica-based inorganic adhesives include water glass, silica sol, and alumina sol.

[0172] The adhesive 12 may be a mixture of an inorganic adhesive and an organic adhesive. Specific examples of the organic adhesive include one or more organic adhesives selected from phenolic resins, epoxy resins, acrylic resins, urethane resins, polyester resins, melamine resins, silicone resins, fluororesins, and copolymers thereof.

[0173] <Corrugated laminate, FIG. 4> The corrugated laminate of the present disclosure is formed by laminating the corrugated sheets of the present disclosure.

[0174] In the corrugated laminate of the present disclosure, the number of cells per area of ​​the surface through which air passes is 80 cells / cm 2 More than 135 pieces / cm 2 The following is the result.

[0175] The stepped laminate of the present disclosure (1) adjusts A: the pore volume (measured by mercury intrusion porosimetry) of mesopores to macropores (3 nm to 500 μm), and B: the pore volume (measured by N adsorption) of micropores (less than 3 nm), (2) B, which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A, which act as a driving force for approaching the micropores, and (3) when applied to a dehumidifier, the gas diffusion within the adsorption sheet can be improved, and the dehumidification performance can be improved. Therefore, the stepped laminate preferably has a density of 80 pores / cm. 2 More than 135 pieces / cm 2 More preferably, 85 particles / cm or less. 2 More than 120 pieces / cm 2 More preferably, 90 particles / cm or less. 2 More than 115 pieces / cm 2 The following is the result.

[0176] The stepped laminate of the present disclosure contains silica gel and / or a porous metal complex as a porous material, and when the pore volume determined by mercury porosimetry is A cc / g and the pore volume determined by an N2 adsorption isotherm at a relative pressure p / p0 = 0.4 is B cc / g, the value B / A obtained by dividing B by A is 0.25 or less.

[0177] The stepped laminate of the present disclosure contains silica gel and / or a porous metal complex as a porous material, and when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

[0178] The pore volume A obtained by mercury intrusion porosimetry, the pore volume B at a relative pressure p / p0 = 0.4 obtained by N2 adsorption isotherm, the pore volume C in the pore diameter range of 3 nm to 500 μm, and the pore volume D in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 are as described above.

[0179] The corrugated laminate of the present disclosure is formed by stacking the corrugated sheets of the present disclosure.

[0180] An example of a corrugated laminate is shown in Figure 4. The corrugated laminate shown in Figure 4(B) is formed by winding the corrugated sheet (C) shown in Figure 3(C) around a rotor as shown in Figure 4(A), and has a honeycomb shape.

[0181] <Adsorption Element> The adsorption element of the present disclosure is made of the corrugated laminate of the present disclosure.

[0182] The adsorption element is manufactured by forming one or more adsorption sheets into a predetermined shape and structure. For example, the adsorption element is manufactured by laminating a corrugated adsorption sheet onto a liner-shaped adsorption sheet using an adhesive (corrugated sheet), and then winding the resulting sheet into a rotor to produce a honeycomb-structured corrugated laminate.

[0183] The adsorption element is made of a stepped laminate. The adsorption element is installed in the flow path of the gas to be treated in a dehumidifier (adsorption / desorption treatment device). The dehumidifier brings the gas to be treated into contact with the adsorption element, causing the target adsorption substances contained in the gas to be adsorbed by the porous material in the adsorption element.

[0184] The adsorption element is manufactured by using one or more stepped laminates to form a structure according to the application or purpose. The type of the adsorption element is not particularly limited, and any conventionally known type can be used.

[0185] By using a pleated adsorption sheet, a cross-flow type adsorption element can be manufactured, and by using a honeycomb type adsorption sheet, a parallel flow type adsorption element can be manufactured.

[0186] Cross-flow type adsorption elements and parallel flow type adsorption elements have a structure that provides a large contact area with the gas to be treated, so they have high adsorption performance for the substances to be adsorbed, and can also reduce pressure loss in the adsorption element.

[0187] Compared to cross-flow type adsorption elements, parallel flow type adsorption elements are superior in terms of preventing clogging due to mist and dust, reducing pressure loss, and reducing weight, and therefore can be more preferably used in adsorption / desorption treatment devices.

[0188] <Dehumidifier, FIG. 5> The dehumidifier of the present disclosure includes a rotor, an adsorption zone air supply passage, and a regeneration zone air supply passage.

[0189] The rotor is a rotor that rotates the adsorption element of the present disclosure around a rotation axis, and has an adsorption zone and a regeneration zone along the circumferential direction, which is the rotation direction of the rotor.

[0190] The adsorption zone air supply passage is an adsorption zone air supply passage that supplies the air to be treated to the adsorption zone so that moisture in the air is adsorbed by the adsorption element.

[0191] The regeneration zone air supply passage is a passage that supplies regeneration air to the regeneration zone for desorbing moisture from the adsorption element that has adsorbed moisture.

[0192] A dehumidifier (adsorption / desorption treatment device) is a device equipped with an adsorption element, and is configured to bring the gas to be treated into contact with the adsorption element to adsorb the substances to be adsorbed contained in the gas to be treated onto a porous material, and to bring the regeneration gas into contact with the adsorption element that has adsorbed the substances to be adsorbed, thereby desorbing the substances to be adsorbed from the porous material.

[0193] The dehumidifier of the present disclosure includes a rotor, an adsorption zone air supply passage, and a regeneration zone air supply passage.

[0194] The rotor of the dehumidifier is a rotor that rotates the adsorption element around a rotation axis, and has an adsorption zone and a regeneration zone along the circumferential direction, which is the rotation direction of the rotor.

[0195] The adsorption zone air supply passage of the dehumidifier supplies the air to be treated to the adsorption zone, where moisture in the air is adsorbed by the adsorption element.

[0196] The regeneration zone air supply passage of the dehumidifier supplies regeneration air to the regeneration zone for desorbing moisture from the adsorption element that has adsorbed moisture.

[0197] The dehumidifier is, for example, a rotor-rotating type continuous adsorption / desorption treatment device 3 as shown in Figure 5. The continuous adsorption / desorption treatment device 3 is equipped with a cylindrical adsorption element 4 that is rotatable around a rotation axis L by driving a motor. The adsorption element 4 is equipped with, for example, a honeycomb-structured stepped laminate 2 as shown in Figure 4(B). The adsorption element 4 is divided into an adsorption zone 40 and a desorption zone 41 in the circumferential direction around the rotation axis L, and the stepped laminate 2 moves alternately between the adsorption zone 40 and the desorption zone 41 as the adsorption element 4 rotates.

[0198] The gas to be treated is supplied to the adsorption zone 40 of the adsorption element 4 by driving the fan 5, and as it passes through the step-processed stack 2 located in the adsorption zone 40, the adsorbent substances contained in the gas to be treated are adsorbed by the porous material contained in the step-processed stack 2. The regeneration gas is heated by a heat source 6 such as a heater and is supplied to the desorption zone 41 of the adsorption element 4 by driving the fan 7, and as it passes through the step-processed stack 2 located in the desorption zone 41, the adsorbent substances are desorbed from the porous material. This regenerates the porous material.

[0199] The rotor rotation type dehumidifier is not limited to the above-mentioned example, and other conventionally known dehumidifiers can also be used. The dehumidifier is not limited to the rotor rotation type dehumidifier.

[0200] The adsorption sheets, corrugated sheets, corrugated laminates, adsorption elements, and dehumidifiers can be used for a variety of purposes, such as air dehumidification, air deodorization, air purification, gas separation, etc. The adsorption sheets, corrugated sheets, corrugated laminates, adsorption elements, and dehumidifiers can be used to reduce malodorous components indoors, inside vehicles, on wallpaper, in furniture, interior materials, resin molded bodies, electrical equipment, etc.

[0201] The adsorbent sheets, corrugated sheets, corrugated laminates, adsorption elements, and dehumidifiers can be used for the purpose of separating and recovering organic solvents in the air emitted from factories, etc. The adsorbent sheets, corrugated sheets, corrugated laminates, adsorption elements, and dehumidifiers can be used for the purpose of adjusting and dehumidifying the air in spaces inside homes, buildings, condominiums, hospitals, factories, commercial facilities, as well as various vehicles such as automobiles, trains, and airplanes.

[0202] The adsorption sheet of the present disclosure adjusts A: the pore volume (measured by mercury intrusion porosimetry) of mesopores to macropores (3 nm to 500 μm), and B: the pore volume (measured by N2 adsorption) of micropores (less than 3 nm).

[0203] In the adsorption sheet of the present disclosure, B, which is directly responsible for gas adsorption and affects the adsorption / desorption rate, and A, which acts as a driving force for approaching the micropores.

[0204] It is important that the adsorption sheet of the present disclosure has B<<A (or D<<C), and by having B / A (or D / C) be 0.25 or less, gas diffusion within the adsorption sheet can be carried out with high efficiency.

[0205] In the adsorbent sheet of the present disclosure, the range of A (or C) is preferably 1.5 to 3, and more preferably 1.5 to 2.8.

[0206] In the adsorption sheet of the present disclosure, the range of B (or D) is preferably 0.1 to 0.4, and more preferably 0.1 to 0.38.

[0207] By applying the adsorption sheet (corrugated sheet, corrugated laminate, and adsorption element) of the present disclosure to a dehumidifier, the gas diffusion within the adsorption sheet can be improved, and the dehumidification performance can be improved.

[0208] The adsorption sheet, the corrugated sheet, the corrugated laminate, the adsorption element, and the dehumidifier according to the present disclosure have been described in accordance with certain embodiments. The adsorption sheet, the corrugated sheet, the corrugated laminate, the adsorption element, and the dehumidifier according to the present disclosure are not limited to the above-described embodiments, and various modifications are possible without departing from the spirit and scope of the present disclosure.

[0209] The functions and effects of the suction sheet of the present disclosure will be specifically described by showing examples of the suction sheet of the present disclosure, but the suction sheet of the present disclosure is not limited to the examples.

[0210] Example 1: Sodium silicate with a SiO2 / Na2O molar ratio of 2.9 was added dropwise to sulfuric acid with a concentration of 18% by weight to produce silica hydrogel. The produced silica hydrogel was washed with a large amount of water, then immersed in sulfuric acid adjusted to pH 4 at a temperature of 30°C for about 2 hours, filtered, and dried at 150°C to obtain silica gel.

[0211] The above-prepared silica gel was mixed in a ratio of 60 mass % (excluding solvent molecules), 16 mass % of aramid fiber as non-fibrillated fiber, 10 mass % of aramid fiber as fibrillated fiber, and 14 mass % of polyvinyl alcohol (PVA) fiber as an organic binder with a water dissolution temperature of 70°C (catalog value), and the mixture was thoroughly stirred.

[0212] The suspension was thoroughly stirred and kept in a dispersed state, and a polymer flocculant, Tetsuflock (manufactured by Nittetsu Mining Co., Ltd.), was added dropwise at a rate of 10 ml / g to the total material, resulting in a basis weight of 75 g / m 2 An adsorption sheet was prepared by a wet papermaking method using the mass of the adsorption sheet.

[0213] The adsorbent sheet was then subjected to a solvent removal treatment at 130° C. to obtain an adsorbent sheet. The porosity of the obtained adsorbent sheet was measured by mercury intrusion porosimetry.

[0214] Furthermore, it was confirmed that it is possible to form a honeycomb shape by bonding the flat sheet and corrugated sheet of the created adsorption sheet using a vinyl acetate adhesive to the extent that the adhesive parts of the honeycomb do not peel off (corrugated sheet), and then wrap the corrugated sheet around a core material using the vinyl acetate adhesive to the extent that the adhesive parts do not peel off (corrugated laminate), and process it into a rotor-shaped cylindrical element (adsorption element) with a thickness of 200 mm and an outer diameter of 300 mm.

[0215] The adhesive content ratio of this rotor-shaped cylindrical adsorption honeycomb element (adsorption element) was 8.2 wt %.

[0216] The dehumidifying performance of this rotor-shaped cylindrical adsorbent honeycomb element (adsorbent element) was evaluated.

[0217] (Example 2) 80% by mass (excluding solvent molecules) of silica gel prepared by the same process as in Example 1, 8% by mass of aramid fiber as non-fibrillated fiber, 5% by mass of aramid fiber as fibrillated fiber, and 7% by mass of the same PVA fiber as in Example 1 as an organic binder were mixed and thoroughly stirred.

[0218] Other operations were the same as in Example 1, and an adsorption sheet was produced by a wet papermaking method, and the porosity of the adsorption sheet was measured by mercury intrusion porosimetry.

[0219] Furthermore, similarly to Example 1, a rotor-shaped cylindrical adsorption honeycomb element (adsorption element) was produced using the prepared adsorption sheet, and the dehumidification performance was evaluated.

[0220] Example 3 PCN250 was synthesized by dissolving 50 g of Fe(NO3)3·9H2O and 10 g of azobenzene-3,3′-5,5′-tetracarboxylic acid in 2 L of N,N-dimethylformamide and 1 L of acetic acid, and heating the solution at 150° C. for 24 hours.

[0221] The PCN250 sample prepared above was mixed in a ratio of 60% by mass (excluding solvent molecules), 16% by mass of aramid fiber as non-fibrillated fiber, 10% by mass of aramid fiber as fibrillated fiber, and 14% by mass of the same PVA fiber as in Example 1 as an organic binder, and the mixture was thoroughly stirred.

[0222] The suspension was thoroughly stirred and kept in a dispersed state, and a polymer flocculant, Tetsuflock (manufactured by Nittetsu Mining Co., Ltd.), was added dropwise at a rate of 10 ml / g to the total material, resulting in a basis weight of 65 g / m 2 An adsorption sheet was prepared by a wet papermaking method using the mass of the adsorption sheet.

[0223] The adsorbent sheet was then subjected to a solvent removal treatment at 130° C. to obtain an adsorbent sheet. The porosity of the obtained adsorbent sheet was measured by mercury intrusion porosimetry.

[0224] Furthermore, similarly to Example 1, a rotor-shaped cylindrical adsorption honeycomb element (adsorption element) was produced using the prepared adsorption sheet, and the dehumidification performance was evaluated.

[0225] (Example 4) 80% by mass (excluding solvent molecules) of the PCN250 sample prepared by the same process as in Example 3, 8% by mass of aramid fiber as non-fibrillated fiber, 5% by mass of aramid fiber as fibrillated fiber, and 7% by mass of the same PVA fiber as in Example 1 as an organic binder were mixed and thoroughly stirred.

[0226] Other operations were the same as in Example 3, and an adsorption sheet was produced by a wet papermaking method, and the porosity of the adsorption sheet was measured by mercury intrusion porosimetry.

[0227] Furthermore, similarly to Example 1, a rotor-shaped cylindrical adsorption honeycomb element (adsorption element) was produced using the prepared adsorption sheet, and the dehumidification performance was evaluated.

[0228] (Comparative Examples 1 and 2) 30 g / m as substrate 2 The glass nonwoven fabric was impregnated with an aqueous solution of sodium silicate with a SiO2 / Na2O molar ratio of 2.9, and semi-dried using a dryer until it was ready for honeycomb (stage) processing.

[0229] In Comparative Example 1, the number of cells per area of ​​the surface through which air passes is set to 95 cells / cm 2 In Comparative Example 1, the number of cells was set to 95 / cm. 2 When the mixture was prepared, the cells were severely clogged and it was not possible to obtain a clean corrugated sheet, and therefore it was not possible to obtain a honeycomb element.

[0230] In Comparative Example 2, the number of cells per area of ​​the surface through which air passes is set to 30 cells / cm 2 A corrugated sheet was created.

[0231] In Comparative Example 2, the flat sheet and corrugated sheet of the adsorption sheet were then bonded together using an emulsion containing amorphous silica and water to the extent that the adhesive parts of the honeycomb would not peel off, forming a honeycomb shape, and further, using the emulsion, a corrugated sheet was wrapped around a core material to the extent that the adhesive parts would not peel off, and it was confirmed that this could be processed into a rotor-shaped cylindrical element with a thickness of 200 mm and an outer diameter of 300 mm.

[0232] The cylindrical element was immersed in sulfuric acid with a concentration of 18% by weight to produce a honeycomb element carrying silica hydrogel. The produced silica hydrogel was washed with a large amount of water, then immersed in sulfuric acid adjusted to pH 4 at a temperature of 30°C for about 2 hours, and dried at 150°C to obtain a honeycomb element carrying silica gel.

[0233] The dehumidifying performance was evaluated using this rotor-shaped cylindrical adsorption honeycomb element.

[0234] (Dehumidification performance evaluation) (1) An adsorption element is fixed in an adsorption / desorption chamber with an adsorption zone:regeneration zone ratio of 3:1. (2) Gas to be treated at a temperature of 25°C and humidity of 5.4g / kg-DA is supplied to the adsorption zone at a passing air velocity of 2m / s. (3) Gas at a temperature of 140°C and humidity of 5.4g / kg-DA is supplied to the desorption zone.

[0235] The removal rate % was calculated using the following formula: Removal rate % = (humidity at the entrance of the adsorption zone 5.4 g / kg-DA - humidity at the exit of the adsorption zone g / kg-DA) / (humidity at the entrance of the adsorption zone 5.4 g / kg-DA) * 100

[0236] (Mercury intrusion porosimetry measurement) The sample was cut into a size of approximately 10 mm x 20 mm and then vacuum dried at 150°C for 24 hours. The porosity was measured using an AutoPoreIV 9520 manufactured by Micromeritics. The pore measurement range was approximately 3 nm to 500 μm.

[0237] The pore volume of the adsorption sheet A (mesopores to macropores, 3 nm to 500 μm) is measured using the mercury intrusion method.

[0238] (N2 adsorption isotherm) 50 mg of a sample is collected, dried overnight in vacuum at 150°C, and then weighed.

[0239] Using a high-precision gas / vapor adsorption analyzer (BELSORP-maxII, manufactured by MicrotracBEL), the adsorption amount of nitrogen gas at the boiling point of liquid nitrogen (-195.8°C) was measured at a relative pressure of 3.0 x 10 -8 Measurements were taken at 80 points while gradually increasing the pH in the range of 0.05 to 0.99, and an adsorption isotherm was created.

[0240] The analysis software (BELMaster Version 7.3.2.0) attached to the device was used to calculate the pore volume [cm by the BET method, with the relative pressure set at p / p0 = 0.4, which corresponds to approximately 3 nm. 3 / g].

[0241] The pore volume of the adsorption sheet B: micropores (less than 3 nm) is measured using the N2 adsorption isotherm.

[0242]

[0243] It is assumed that the porosity varies depending on the amount of fibrillated fiber. For example, when the adsorbent content is 80% by weight, the other fibers are 20% by weight. The amount of fibrillated fiber in the example is 5% by weight.

[0244] In the region where the amount of fibrillated fibers is as low as 1% by weight or less, the amount of dehumidifying agent inevitably becomes small, and the dehumidifying performance tends to decrease.

[0245] In the region where the amount of fibrillated fibers is as high as about 20% by weight, the paper loses strength and tends to have poor corrugation properties.

[0246] The adsorbent sheet of the present disclosure adjusts A (or C): the pore volume of mesopores to macropores (3 nm to 500 μm) (measured by mercury intrusion porosimetry), and B (or D): the pore volume of micropores (less than 3 nm) (measured by N adsorption).

[0247] In the adsorption sheet of the present disclosure, B (or D), which is directly attributable to gas adsorption and affects the adsorption / desorption rate, and A (or C) also serve as a driving force for approaching the micropores.

[0248] It is important that the adsorption sheet of the present disclosure has B<<A (or D<<C), and by having B / A (or D / C) be 0.25 or less, gas diffusion within the adsorption sheet can be carried out with high efficiency.

[0249] In the adsorbent sheet of the present disclosure, the range of A (or C) is preferably 1.5 to 3, and more preferably 1.5 to 2.8.

[0250] In the adsorption sheet of the present disclosure, the range of B (or D) is preferably 0.1 to 0.4, and more preferably 0.1 to 0.38.

[0251] By applying the adsorption sheet (corrugated sheet, corrugated laminate, and adsorption element) of the present disclosure to a dehumidifier, the gas diffusion within the adsorption sheet can be improved, and the dehumidification performance can be improved.

Claims

1. An adsorption sheet containing silica gel and / or a porous metal complex as a porous material, wherein when the pore volume determined by mercury porosimetry is A cc / g and the pore volume determined by N2 adsorption isotherm at a relative pressure p / p0 = 0.4 is B cc / g, the value B / A obtained by dividing B by A is 0.25 or less.

2. An adsorption sheet containing silica gel and / or a porous metal complex as the porous material, wherein when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

3. The adsorption sheet according to claim 1 or 2, which contains 40% to 85% by mass of the silica gel and / or porous metal complex.

4. A corrugated sheet comprising an adsorbent sheet according to claim 1 or 2 bonded together, the flat adsorbent sheet and the corrugated adsorbent sheet being bonded together, and having a large number of cells which serve as air passages.

5. A corrugated laminate obtained by laminating the corrugated sheets according to claim 4.

6. The number of cells per area of ​​the surface through which air passes is 80 / cm 2 More than 135 pieces / cm 2 6. The stepped laminate of claim 5, wherein:

7. A stepped laminate comprising an adsorbent sheet containing silica gel and / or a porous metal complex as a porous material, and having a value of B / A obtained by dividing B by A of 0.25 or less, where A cc / g is the pore volume determined by mercury porosimetry and B cc / g is the pore volume at a relative pressure p / p0 = 0.4 determined by an N2 adsorption isotherm.

8. A stepped laminate, comprising silica gel and / or a porous metal complex as the porous material, wherein when the pore volume in the pore diameter range of 3 nm to 500 μm is C cc / g, and the pore volume in the pore diameter range of less than 3 nm at a relative pressure p / p0 = 0.4 is D cc / g, the value D / C obtained by dividing D by C is 0.25 or less.

9. An adsorption element comprising the stepped laminate of claim 5, 7, or 8.

10. A dehumidifier comprising: a rotor; an adsorption zone air supply passage; and a regeneration zone air supply passage, wherein the rotor rotates the adsorption element described in claim 9 around a rotation axis, and has an adsorption zone and a regeneration zone along a circumferential direction which is the rotation direction of the rotor, the adsorption zone air supply passage is an adsorption zone air supply passage that supplies air to be treated to the adsorption zone to cause the adsorption element to adsorb moisture in the air, and the regeneration zone air supply passage is a regeneration zone air supply passage that supplies regeneration air to the regeneration zone for desorbing moisture from the adsorption element that has adsorbed moisture.

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