Deodorizing filter and method for regenerating the same

Abstract

To regenerate a filter containing a washable and regenerable adsorbent, while enabling efficient removal of moisture from the filter after washing.SOLUTION: A deodorizing filter comprises: a filter member 1 capable of air ventilation along its thickness direction that can be installed on a target in a manner enabling or not requiring replacement, and that contains a washable and regenerable adsorbent; and a holder capable of holding the filter member 1 such that, in the installed state on the target, a surface orthogonal to the thickness direction of the filter member 1 is inclined with respect to the horizontal plane.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a deodorizing filter and a method for regenerating the same. [Background technology]

[0002] Various deodorizing filters have been developed for the purpose of removing odors and the like. Patent Document 1 discloses a toilet deodorizing filter characterized by carrying a metal phthalocyanine complex, a weakly alkaline metal salt, and a water-soluble copper compound on activated carbon-containing paper. Patent Document 2 discloses a deodorizing filter used in an air purifier that keeps the air environment in a space clean. The deodorizing filter is made of a corrugated substrate made of laminated and bonded paper containing silica gel powder that has been aged by hydrothermal synthesis, and is designed to restore its deodorizing ability by washing with water. Furthermore, Patent Document 3 discloses a deodorizing filter that is formed by filling the cells of a honeycomb with a granular deodorizing agent and sealing the open surfaces on both sides of the honeycomb with an air-permeable substrate, wherein the granular deodorizing agent is a deodorizing agent that can be regenerated by washing with water. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-025118 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-036191 [Patent Document 3] Japanese Patent Application Laid-Open No. 2004-041277 Summary of the Invention [Problem to be solved by the invention]

[0004] The toilet deodorizing filter disclosed in Patent Document 1 decomposes or chemically adsorbs malodorous components using multiple types of carriers, but has the problem that the carriers fall off when used in a high-humidity environment or when washed with water, resulting in a decrease in deodorizing performance. Furthermore, when the deodorizing filters disclosed in Patent Documents 2 and 3 are washed with water to restore their deodorizing performance, the pores of the filter are blocked by the capillary action of water, and the deodorizing performance cannot be exhibited for a certain period of time until the filter dries. If the filter remains wet for a long period of time, depending on the usage environment, odorous components may become concentrated, bacteria may grow, or the adsorbent may be detached or decomposed, which may result in problems such as a decrease in deodorizing performance.

[0005] To improve deodorizing performance, it is preferable to increase the total surface area of ​​the air passages and to incorporate a high amount of deodorizing agent. Assuming that there is a limit to the filter size, the smaller the filter opening, the better, and the smaller the radius of the circle inscribed in the hole, the more advantageous it is for deodorizing. Also, the thicker the filter, the better. On the other hand, to improve drainage, the larger the filter opening, and the thinner the filter, the better. In other words, it is difficult to achieve deodorizing performance, drying performance, and a smaller filter size all at the same time, so it was necessary to compromise on one of them.

[0006] In view of this background technology, the present inventors have conducted extensive research to enable efficient removal of water from a filter after washing when regenerating a filter containing a water-washable regenerative adsorbent, and as a result have completed the present invention. [Means for solving the problem]

[0007] The deodorizing filter of the present invention is a deodorizing filter that can be installed on an installation target in a replaceable or non-replaceable manner, and is configured to include a filter member that is breathable along its thickness direction and includes an adsorbent material that can be washed and reused with water, and a holder that can hold the filter member so that, when installed on the installation target, the surface of the filter member perpendicular to the thickness direction forms an angle with respect to the horizontal plane.

[0008] Furthermore, the method for regenerating a deodorizing filter according to the present invention is a method for regenerating a deodorizing filter having a filter member containing an adsorbent material that can be regenerated by washing with water, in which the filter member is ventilated along its thickness direction, and the filter member is held so that a surface perpendicular to the thickness direction of the filter member forms an angle with respect to the horizontal plane, and then washed with water and dried. [Effects of the Invention]

[0009] According to the present invention, it is possible to efficiently remove moisture from the deodorizing filter after washing with water. [Brief explanation of the drawings]

[0010] [Figure 1] 3A and 3B are explanatory diagrams illustrating an example of a filter member included in the deodorizing filter according to the embodiment of the present invention. [Figure 2] 10A and 10B are explanatory views showing another example of a filter member included in the deodorizing filter according to the embodiment of the present invention. [Figure 3] 10 is an explanatory diagram showing a standard for determining an angle formed by a plane perpendicular to the thickness direction of the filter member with respect to a horizontal plane. FIG. [Figure 4] FIG. 1 is an explanatory diagram showing how to derive formula (2). DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will now be described.

[0012] The deodorizing filter according to this embodiment can be used to remove bad odors by adsorbing odorous components that cause bad odors, for example, in deodorizing devices for various types of equipment, including air purifiers, refrigerators, sanitary equipment, etc. When the deodorizing filter is installed in the installation target, it is installed so that it can be replaced or not, depending on the useful life of the installation target.

[0013] The deodorizing filter includes a filter member 1 that contains a washable and reusable adsorbent and is air permeable along its thickness direction, and a holder that can hold the filter member 1 so that the surface orthogonal to the thickness direction of the filter member 1 forms an angle with the horizontal when the filter member 1 is installed on an installation target. By holding the surface orthogonal to the thickness direction of the filter member 1 at an angle with the horizontal, moisture can be efficiently removed from the deodorizing filter after it has been washed with water, and the configuration of the deodorizing filter that provides such an effect unique to the present invention will be described in more detail below.

[0014] The filter member 1, which is ventilated in the thickness direction, can be dried by ventilating the filter member 1 from the bottom or top in the thickness direction after washing. The method of ventilating and drying is not particularly limited, as it depends on the installation environment of the deodorizing filter. For example, a method of drying by ventilating hot air at 20 to 70°C using a heater can be used. Furthermore, according to the present invention, moisture can be efficiently removed from the deodorizing filter after washing. Therefore, the drying method may be ventilating without using a heater, or indoor natural drying without using a heater or fan. This can prevent deterioration of the adsorbent, filter member 1, and holder due to hot air or direct sunlight. Furthermore, the deodorizing filter can be applied to installations that do not have a heater or fan.

[0015] Here, "water-washable and reusable" means that an adsorbent whose deodorizing performance has deteriorated can be restored by washing it with water in any manner and drying it. Whether an adsorbent can be washed with water and reusable can be determined by comparing the deodorizing performance (the time required for the adsorbent to break through or the deodorizing capacity) of the adsorbent after washing and drying with that of the initial state. For example, if the deodorizing performance of an adsorbent after washing and drying is 50% or more of its initial deodorizing performance against sulfur-containing compounds such as hydrogen sulfide and methyl mercaptan, or nitrogen-containing compounds such as ammonia and trimethylamine, it can be said to be water-washable and reusable. The installation target preferably has a mechanism for ventilating and drying the filter member 1, and more preferably has both a mechanism for ventilating and drying the filter member 1 and a mechanism for washing the filter member 1. If the installation target does not have a mechanism for washing the filter member 1, the installation target is preferably configured so that the filter member 1 can be removed, washed, and then returned to the installation target and dried.

[0016] In this embodiment, examples of water-washable and recyclable adsorbents include porous materials such as zeolite, alumina, activated carbon, and porous silica. It is preferable to use an adsorbent that has high contact efficiency with malodorous components. The shape of the adsorbent may be spherical or non-spherical, such as plate, flake, or block. The particle size of the adsorbent is preferably D99 of 0.1 to 500 μm. The specific surface area is preferably 100 to 1500 m. 2 / g. The pore size of the porous material used as the adsorbent is preferably mesopores of 2 to 50 nm. The adsorbent may support a metal compound, a deodorant, a decomposing agent for malodorous components, or may be doped with metal atoms. Two or more types of adsorbents may also be used.

[0017] In this embodiment, among the above adsorbents, mesoporous silica having mesopores is particularly preferred, and mesoporous silica in which metal atoms M are doped into the siloxane bonds of the silica pore walls by replacing some of the Si atoms in the siloxane bonds (—Si—O—) that form the silica skeleton with metal atoms M is more preferred. The metal atoms M doped into the siloxane bonds of the silica pore walls are preferably at least one selected from the group consisting of Cu, Mn, Co, and Zn, with Cu being particularly preferred. Doping these metal atoms M into the siloxane bonds of the silica pore walls allows for large amounts of adsorption of multiple types of odorous compounds, such as sulfur-containing compounds and nitrogen-containing compounds. Furthermore, mesoporous silica doped with metal atoms M can exhibit excellent adsorption performance for odorous components even during use in a high-humidity environment or in a wet state after washing with water.

[0018] The specific surface area of ​​mesoporous silica is 500 to 1200 m 2 / g. Preferably, the specific surface area of ​​the mesoporous silica is 500 m 2 If the specific surface area is 1200 m / g or more, the contact area between the metal atom M doped in the siloxane bond of the silica pore wall and the odorant is sufficiently secured, and a high adsorption rate can be obtained. 2 If the pore size is 0.1 / g or less, the strength required to maintain the pore structure can be ensured.

[0019] In such mesoporous silica, the content of metal atoms M doped into the siloxane bonds of the silica pore walls to improve deodorizing performance is preferably 0.01 to 15 mass%, more preferably 0.1 to 13 mass%, and particularly preferably 2 to 10 mass%. If the content of metal atoms M is 0.01 mass% or more, sufficient adsorption performance can be achieved. On the other hand, if the content is 15 mass% or less, mesoporous silica in which metal atoms M are doped into the siloxane bonds of the silica pore walls can be easily synthesized.

[0020] It is also preferable to dope the siloxane bonds in the silica pore walls with Al or Fe atoms in addition to the metal atom M. That is, it is preferable to replace some of the Si atoms in the siloxane bonds forming the silica skeleton with the metal atom M, and to replace some of the other Si atoms with Al or Fe atoms. This suppresses hydrolysis of the silica skeleton formed by siloxane bonds, making the pore structure less susceptible to collapse. As a result, the hydrothermal durability of the mesoporous silica is improved, and deterioration due to washing with water or hot air drying can be suppressed. Furthermore, doping with Al or Fe atoms improves the ability to release adsorbed odorous components by washing with water, thereby restoring deodorizing performance.

[0021] When Al atoms or Fe atoms are doped into the siloxane bonds of the silica pore walls, the content of Al atoms or Fe atoms is preferably 0.01 to 15% by mass, more preferably 0.1 to 5% by mass. If the content of Al atoms or Fe atoms is 0.01% by mass or more, hydrolysis of the silica skeleton is suppressed, and a decrease in the specific surface area over time during storage can be suppressed. On the other hand, if the content is 15% by mass or less, the specific surface area of ​​500 m 2 A high specific surface area of ​​more than / g can be achieved.

[0022] Adsorbents such as mesoporous silica can be impregnated onto the entire or partial filter member 1 by, for example, preparing an impregnation liquid for impregnating the adsorbent onto the filter member 1. When preparing the impregnation liquid, a resin-based binder such as an acrylic resin or an epoxy resin, or a silica binder such as water glass, silica microparticles, polysilazane, or silicone may be used to fix the adsorbent to the filter member 1. When the adsorbent is porous silica, using a silica-based binder as the binder component can prevent the adsorbent from falling off the binder during washing and drying. Furthermore, if the binder component is organic microparticles such as an acrylic resin or silica microparticles, these can impart an uneven shape to the surface of the filter member 1. As a result, good drainage is achieved even when the angle between the plane perpendicular to the thickness direction of the filter member 1 and the horizontal plane is small. The mass ratio of the adsorbent to the binder component in the impregnation solution is not particularly limited, but is preferably adjusted so that the adsorbent is not buried in the binder component when the adsorbent is impregnated onto the filter member 1. The mass ratio is usually 1:99 to 99:1, preferably 20:80 to 80:20, and more preferably 20:80 to 50:50. The amount of impregnation is not particularly limited, but is preferably 1 to 100 g / m 2 Preferably, the impregnation liquid is water. The impregnation liquid may be prepared so as to contain a pH adjuster, a surfactant, a viscosity adjuster, etc. as needed. The solvent used in the impregnation liquid may be water, a mixed solvent of water and a water-miscible organic solvent such as a ketone solvent or an ether solvent, or a water-immiscible organic solvent.

[0023] The adsorbent can be attached to the filter member 1, for example, by submerging the filter member 1 in an adsorbing liquid and then pulling it out, or by spraying the adsorbing liquid onto the filter member 1 with a sprayer, followed by natural drying or heat drying.

[0024] The filter member 1 preferably has a plurality of through-holes that penetrate the filter member 1 in the thickness direction and are surrounded by partition walls arranged along the thickness direction. The through-holes may penetrate the filter member 1 in the thickness direction, but may be angled at, for example, 45° or less with respect to the thickness direction of the filter member 1. When the filter member 1 is held so that a surface perpendicular to the thickness direction of the filter member 1 forms an angle with the horizontal plane HP, the angle between the penetration direction of the through-holes and the horizontal plane HP is preferably 70° or more, more preferably 80° or more, and particularly preferably 90° (vertical). This allows for more efficient removal of moisture from the filter after washing with water. A filter member 1 configured so that odorous components contained in air passing through the through-holes are adsorbed by an adsorbent exposed on the inner surface of the through-holes (e.g., mesoporous silica attached to the inner surface of the through-holes) is preferred because this allows for the adsorption of a larger number of odorous components; however, the specific configuration of the filter member 1 is not particularly limited.

[0025] For example, a honeycomb structure consisting of hexagonal, quadrangular, triangular, or circular cells may penetrate the filter member 1 in the thickness direction or at an angle. A portion or the entire filter member 1 may be composed of one or more of these cell structures. The sides of the polygonal cells may not be the same length and may be straight or curved. Furthermore, the vertices of the polygonal cells may not have equal internal angles and may have rounded corners. The filter member 1 is preferably configured to have a large surface area per unit volume (specific surface area) and low pressure loss. A corrugated honeycomb structure is particularly preferred, in which flat partition walls (base sheets) 11 and corrugated partition walls (corrugated sheets) 12 are alternately arranged, with multiple through-holes formed in a cellular pattern along the thickness direction between them (see Figures 1 and 2). The corrugated honeycomb structure of the filter member 1 exhibits high deodorizing performance and improves moisture removal efficiency, especially during the initial drying stage after washing.

[0026] When the filter member 1 has a corrugated honeycomb structure, the base sheet 11 may be disposed, for example, parallel to the longitudinal direction (horizontal direction) as shown in Fig. 1 or parallel to the short-side direction (vertical direction) as shown in Fig. 2. The orientation of the base sheet 11 is preferably designed taking into consideration the tilt direction when the filter member 1 is held so that a plane perpendicular to the thickness direction of the filter member 1 forms an angle with respect to the horizontal, i.e., the direction from the upper part of the filter member 1 to the lower part when the filter member 1 is installed on an installation target. For example, using the example shown in Fig. 1 as an example, when the filter member 1 is held so that a plane perpendicular to the thickness direction of the filter member 1 forms an angle with respect to the horizontal, with the short-side direction (vertical direction) as the axial direction, the front part in the figure is positioned lower, and the base sheet 11 is preferably disposed so that it is parallel to the tilt direction. That is, if the base sheet is arranged parallel to the tilt direction (drainage direction) when the filter member 1 is installed on the installation target, the number of times that water is blocked by the recesses of the corrugated sheet 12 or the base sheet 11 is reduced, making it easier to drain. Furthermore, when the deodorizing filter is used in a high-humidity environment, the surfaces of the cells and adsorbent are less likely to become covered with condensed water, improving deodorizing performance.

[0027] When the filter member 1 is constructed with such a structure, the number of cells of the filter member 1 is set to 30 cells / inch, taking into consideration the adsorption of odor components to the adsorbent, water permeability when washed and regenerated, and ventilation when ventilated and dried. 2 Over 600 cells / inch 2 Preferably, it is equal to or less than 80 cells / inch, and more preferably, it is equal to or less than 80 cells / inch. 2 Over 400 cells / inch 2 120 cells / inch or less is particularly preferred. 2 Over 400 cells / inch 2 In addition, when considering the water permeability during water washing and regeneration, the air permeability of the constituent substrate is 10 to 3000 cm 3 / (cm 2 s), and 10 to 300 cm 3 / (cm 2It is more preferable that the thickness of the material of the filter member 1 is 0.01 to 5 mm.

[0028] The material of the filter member 1 is not particularly limited as long as it is water-permeable, but examples include nonwoven fabric, foamed resin, inorganic paper such as glass fiber or ceramic fiber, materials such as porous ceramics that function as washable and recyclable adsorbents, metal materials such as aluminum, and composite materials. Among these, water-resistant paper materials or porous ceramics that are resistant to deterioration even after repeated washing and heating and drying are preferred, and water-resistant paper materials that can be easily formed into various shapes and dimensions are even more preferred. Highly water-permeable inorganic paper is also ideal because it can efficiently remove moisture even when the plane perpendicular to the thickness direction of the filter member 1 forms a low angle with the horizontal. The molded product may be an extrusion molded product, and in this case, it may be molded from only the adsorbent or a mixture of the adsorbent and a resin component. The shape of the filter member 1 is also not limited, and it can be formed into any three-dimensional shape, such as a rectangular parallelepiped, cube, or cylinder, taking into account ease of washing and ventilation drying.

[0029] Furthermore, in consideration of drying properties during ventilation drying, it is preferable that the thickness of the filter member 1 be made as short as possible without impairing adsorption performance due to insufficient length of the through-holes (i.e., the adsorption path through which air containing odorous components passes). For example, when the filter member 1 is formed to have a rectangular parallelepiped appearance, the thickness of the filter member 1 is preferably equal to or less than the length of the short side in the plane perpendicular to the thickness direction. When the filter member 1 is made of paper, it is preferable that the thickness of the paper after molding the filter member 1 is 1 mm or less.

[0030] As described above, a deodorizing filter including such a filter member 1 further includes a holder that can hold the filter member 1 so that the surface orthogonal to the thickness direction of the filter member 1 forms an angle with the horizontal plane (i.e., the plane orthogonal to the vertical direction) HP when the deodorizing filter is installed on the installation target. The holder that holds the filter member 1 in this way may be configured as part of the installation target, and it is sufficient that the filter member 1 is held so that the surface orthogonal to the thickness direction of the filter member 1 forms an angle with the horizontal plane HP when the filter is installed on the installation target.

[0031] The angle θ formed by the plane perpendicular to the thickness direction of the filter member 1 with respect to the horizontal plane HP is preferably 5° or greater, and more preferably 10° or greater. More specifically, for example, when the filter member 1 is formed to have a rectangular parallelepiped appearance, the angle can be determined as follows. That is, when the vertical direction (the short-side direction in the illustrated example) is the axial direction, the angle θ can be determined within a range that achieves the desired effect based on the angle between the upper end of the lowermost side and the lower end of the uppermost side, of the side surfaces facing each other in the horizontal direction (the longitudinal direction in the illustrated example) (see FIG. 3 ). The angle θ is preferably set to be equal to or greater than this angle. In other words, the following relationship is preferably established between the angle θ formed by the plane perpendicular to the thickness direction of the filter member 1 with respect to the horizontal plane HP, the thickness T of the filter member 1, and the horizontal length W of the filter member 1: θ≧Arctan(T / W) ·····(1)

[0032] In addition, the upper limit of the angle θ formed by the surface orthogonal to the thickness direction of the filter member 1 with respect to the horizontal plane HP can be appropriately determined so that the space when installed on the installation target does not become too large in consideration of the thickness of the filter member 1. For example, assuming that the filter member 1 is held so that the surface orthogonal to the thickness direction of the filter member 1 is perpendicular to the horizontal plane HP, in that case, the length of the perpendicular line dropped vertically from the uppermost part of the filter member 1 to the horizontal plane HP is set as h0, and when the filter member 1 is held so that the surface orthogonal to the thickness direction of the filter member 1 forms an angle θ with respect to the horizontal plane HP, if the length of the perpendicular line dropped vertically from the uppermost part of the filter member 1 to the horizontal plane HP is set as h, it is preferable that the filter member 1 is held so that the relationship h < h0 holds. More specifically, when the filter member 1 is formed to have a rectangular parallelepiped or cubic appearance, the height of the uppermost part of the filter member 1 with respect to the horizontal plane HP, that is, the length of the perpendicular line dropped vertically from the uppermost part of the filter member 1 to the horizontal plane HP (hereinafter referred to as "installation height") H is preferably set to an angle shorter than the lateral length W of the filter member 1. In other words, the following relationship preferably holds among the angle θ formed by the surface orthogonal to the thickness direction of the filter member 1 with respect to the horizontal plane HP, the thickness T of the filter member 1, and the lateral length W of the filter member 1. θ < Arcsin((W 2 - T 2 ) / (W 2 + T 2 )) ·····(2)

[0033] The installation height H when the filter member 1 is erected vertically is equal to the lateral length W of the filter member 1. Therefore, if the filter member 1 is held at an angle θ exceeding the upper limit defined by the above formula (2), due to the thickness of the filter member 1, its installation height H becomes larger than when the filter member 1 is erected vertically, and it takes up space in the height direction by that amount. Therefore, by defining the upper limit of the angle θ by the above formula (2), such problems can be effectively avoided.

[0034] Here, the above formula (2) is derived as follows: As shown in Fig. 4, if the length of the diagonal line of the side surface of the filter member 1 along the horizontal direction is F and the angle between the diagonal line and the long side along the horizontal direction is θ0, the relationship between these and the installation height H is as follows: H=F sin(θ+θ0) (3) Therefore, when the installation height H is shorter than the lateral length W of the filter member 1, the following equation is established. sin(θ+θ0) <W / F ·····(4) The above formula (4) θ+θ0 <Arcsin(W / F) ·····(5) and solving this for θ one by one, we get θ <Arcsin(W / F)-θ0·····(6) θ <Arcsin(W / F)-Arcsin(T / F) ·····(7) θ <Arcsin((W / F)(1-(T / F) 2 ) 1 / 2 -(T / F)(1-(W / F) 2 ) 1 / 2 ) (8) θ <Arcsin((W / F)((F 2 -T 2 ) / F 2 ) 1 / 2 -(T / F)((F 2 -W 2 ) / F 2 ) 1 / 2 ) ·····(9) This becomes: and, F 2 =W 2 +T 2 ·····(10) Since the following relationship holds, the above formula (9) can be rearranged to derive the above formula (2).

[0035] In this embodiment, the holder is not limited to a specific configuration as long as it is configured to hold the filter member 1 as described above. For example, when a deodorizing filter is to be replaceably installed in an installation target, the deodorizing filter may be configured to be detachable in a cartridge format depending on the structure of the installation location of the installation target. A movable mechanism may be provided that rotates the filter member 1 around an axis during ventilation drying, so that the filter member 1 is held as described above.

[0036] Furthermore, when the holder contacts the bottom surface of the filter member 1, the bottom surface is not closed, and can be formed with through holes, for example, to prevent the drainage of water removed from the filter member 1 from being impaired. A lattice-like, net-like, hollow, or other structure can be used to allow water removed from the filter member 1 to drip down the holder, and drainage can be improved by adjusting the spacing and shape of the lattice. It is desirable that the surface of such a holder be smooth and easy for water to slide off. [Example]

[0037] The present invention will be described in more detail below with reference to specific examples.

[0038] First, an impregnation liquid for impregnating mesoporous silica as an adsorbent onto a filter member was prepared as follows.

[0039] (Impregnation solution 1) 50 parts by mass of a slurry (concentration 20%) of mesoporous silica (manufactured by Sigma-Aldrich Corporation; MCM-41 type (hexagonal); product number 643645) and 50 parts by mass of a silica binder were mixed to prepare impregnation solution 1, in which the mass ratio of mesoporous silica to silica-based binder components was 50:50.

[0040] (Impregnation solution 2) Hexadecyltrimethylammonium chloride as a surfactant, copper chloride dihydrate as a copper salt, and aluminum chloride hexahydrate as an aluminum salt were added to water as a solvent and stirred at 100°C for 1 hour. After the solution was cooled to room temperature, tetraethoxysilane as a silica source was added to the solution in which micelles had formed and stirred. Next, sodium hydroxide was added as a condensation catalyst and stirred. The amounts of each compound added per mole of tetraethoxysilane were as follows: Surfactant (hexadecyltrimethylammonium chloride): 0.225 mol Copper chloride dihydrate: 0.0204 mol Aluminum chloride hexahydrate: 0.0482 mol Water: 125 moles Sodium hydroxide: 0.325 mol Next, the micelles in the solution were collected as a precursor, thoroughly dried, and then calcined to remove the organic components, producing mesoporous silica (Cu2Al2) containing 2 wt% Cu and 2 wt% Al. Impregnation liquid 2 was prepared in the same manner as impregnation liquid 1, except that the mesoporous silica thus prepared was used.

[0041] (Impregnation solution 3) Hexadecyltrimethylammonium chloride as a surfactant, copper chloride dihydrate as a copper salt, and iron chloride hexahydrate as an iron salt were added to water as a solvent and stirred at room temperature for 30 minutes. Tetraethoxysilane as a silica source was then added to the solution in which micelles had formed and stirred. Sodium hydroxide was then added as a condensation catalyst and stirred. The amounts of each compound added per mole of tetraethoxysilane were as follows: Surfactant (hexadecyltrimethylammonium chloride): 0.225 mol Copper chloride dihydrate: 0.1202 mol Iron chloride hexahydrate: 0.0683 mol Water: 125 moles Sodium hydroxide: 0.8 mol The resulting precipitate was then collected by filtration, dried at 50°C for 24 hours, and then calcined at 500°C for 20 hours to produce mesoporous silica (Cu10Fe5) containing 10 wt% Cu and 5 wt% Fe. Impregnation liquid 3 was prepared in the same manner as impregnation liquid 1, except that the mesoporous silica thus prepared was used.

[0042] Next, filter elements formed into a corrugated honeycomb structure using inorganic paper or filter elements with an array of square cells using ABS resin were fabricated as follows. These were submerged in the impregnation solution, pulled out, and then air-dried to obtain samples impregnated with mesoporous silica. The total amount of mesoporous silica and silica-based binder impregnated was 1 g. The filter elements fabricated from ABS resin were treated with the impregnation solution after their surfaces had been hydrophilized using a persulfate solution.

[0043] Filter #120v Cell count: 120 cells / inch 2 The base sheet was fabricated so that the direction in which each through-hole penetrated (grain direction) was inclined at 10° with respect to the thickness direction. The base sheet was arranged as shown in FIG. Filter #120s Cell count: 120 cells / inch 2 The base sheet was fabricated so that the direction in which each through-hole penetrated (grain direction) was perpendicular to a plane perpendicular to the thickness direction. The base sheet was arranged as shown in FIG. Filter #200v Cell count: 200 cells / inch 2 The base sheet was fabricated so that the direction in which each through-hole penetrated (grain direction) was inclined at 10° with respect to the thickness direction. The base sheet was arranged as shown in FIG. Filter #200s Cell count: 200 cells / inch 2 The base sheet was fabricated so that the direction in which each through-hole penetrated (grain direction) was perpendicular to a plane perpendicular to the thickness direction. The base sheet was arranged as shown in FIG. ABS filter For comparison, a filter was created using a 3D printer with an ABS resin base material. The filter wall was approximately 1 mm thick and had an array of 26 uniformly sized rectangular cells arranged vertically and 10 horizontally.

[0044] Each filter member was fabricated to have a rectangular parallelepiped appearance, with dimensions of length L x width W x thickness T being 27 mm x 66 mm x 11 mm.

[0045] Next, the following experiments were carried out. In all experiments, the drying process was carried out in a room temperature of 20°C, 50% RH atmosphere, and in a windless environment.

[0046] [Experiment 1] A predetermined number of samples were prepared by impregnating mesoporous silica onto filter #120v using impregnation solution 1. The samples were dried at 100°C for 1 hour, then allowed to absorb moisture for 1 hour at 20°C and 50% RH, followed by weight measurement. This was the initial weight. Next, the samples were immersed in a 300 mL container containing 200 mL of pure water (approximately 25°C) for 40 seconds, with the surface of the through-holes parallel to the water surface. After removing the samples with the surface of the through-holes parallel to the water surface, the sample was held so that the surface perpendicular to the thickness direction was at an angle of 0° (Comparative Example 1), 10° (Example 1), or 20° (Example 2) relative to the horizontal plane, with the vertical direction as the axial direction. The weight change of the samples over time was measured for each sample. The samples were held by placing them on two fishing lines stretched in a V-shape at the desired angle. Based on the measurement results, the ratio of the moisture content after 3 minutes of drying to the moisture content immediately after removal was calculated. The results are shown in Table 1. As Comparative Examples 2-1, 2-2, and 3, a filter ABS and a commercially available ceramic filter (length L x width W x thickness T: 27 mm x 66 mm x 11 mm, number of cells: 110 cells / inch) were used. 2 ) was also subjected to similar experiments.

[0047] [Table 1]

[0048] These results confirmed that by holding a permeable filter at an angle to the horizontal, it is possible to efficiently remove water trapped inside the cell. It was also confirmed that drainage was poor at an angle of 0°, regardless of the filter material.

[0049] [Experiment 2] A predetermined number of samples were prepared by impregnating mesoporous silica onto filter #120s using impregnation solution 1. The samples were dried at 100°C for 1 hour, then allowed to absorb moisture for 1 hour at 20°C and 50% RH, followed by weight measurement. This was the initial weight. Next, the samples were immersed in a 300 mL container containing 200 mL of pure water (approximately 25°C) for 40 seconds, with the surface of the through-holes parallel to the water surface. After removing the samples with the surface of the through-holes parallel to the water surface, the samples were held so that the surface perpendicular to the thickness direction was at an angle of 0° (Comparative Example 4), 10° (Example 3), or 20° (Example 4) relative to the horizontal plane, with the vertical direction as the axial direction. The weight change of the samples over time was measured for each sample. The samples were held by placing them on two fishing lines stretched in a V-shape at the desired angle. Based on the measurement results, the ratio of the moisture content after 3 minutes of drying to the moisture content immediately after removal was calculated. The results are shown in Table 2. Similar experiments were also carried out on the filters #200v and #200s as Comparative Example 5, Example 5, Comparative Example 6, and Example 6.

[0050] [Table 2]

[0051] Comparing Experiment 1 and Experiment 2, it was confirmed that the filter was more effective in removing water when the base sheet was arranged parallel to the inclination direction. Furthermore, this effect was demonstrated regardless of the cell size.

[0052] [Experiment 3] A predetermined number of samples were prepared by impregnating mesoporous silica onto filter #120s using impregnation solution 1. The samples were dried at 100°C for 1 hour, then allowed to absorb moisture for 1 hour at 20°C and 50% RH, after which their weights were measured. This was the initial weight. Next, the samples were immersed in a 300 mL container containing 200 mL of pure water (approximately 25°C) for 40 seconds, with the through-hole surface parallel to the water surface. The samples were then removed with the through-hole surface parallel to the water surface. The surface perpendicular to the thickness direction was then held at an angle of 40° (Example 7) or 60° (Example 8) relative to the horizontal, and the weight change over time was measured. The samples were held in place using a holder made of fishing line stretched in a grid pattern (5 mm × 5 mm squares). Based on the measurement results, the ratio of the moisture content after 3 minutes of drying to the moisture content immediately after removal was calculated. The results are shown in Table 3. In Examples 9 and 10, a commercially available ceramic filter (length L x width W x thickness T: 27 mm x 66 mm x 11 mm, number of cells: 110 cells / inch) was used. 2 ) was also subjected to similar tests.

[0053] [Table 3]

[0054] The results of Experiment 3 showed that if a permeable filter is used, drainage is good even when the filter is tilted at a high angle and the through-holes are tilted from the vertical direction to the horizontal plane.

[0055] [Experiment 4] A predetermined number of samples were prepared by impregnating mesoporous silica onto filter #120v using impregnation solution 1. The samples were dried at 100°C for 1 hour, then allowed to absorb moisture at 20°C and 50% RH for 1 hour, and then weighed. This was the initial weight. Next, the samples were immersed in a 300 mL container containing 200 mL of pure water (approximately 25°C) for 40 seconds, with the through-hole surface parallel to the water surface. The samples were removed with the through-hole surface parallel to the water surface, and then held so that the surface perpendicular to the thickness direction was at an angle of 0° (Comparative Example 7) or 60° (Example 11) relative to the horizontal. The samples were held by fixing the outer periphery with an acrylic plate. The number of cells not blocked by water was counted over time, and the opening ratio was calculated from the ratio to the total number of cells. The results are shown in Table 4. Similar experiments were also performed on #120s as Comparative Example 8 and Example 12.

[0056] [Table 4]

[0057] The results of Experiment 4 confirmed that the filter of the present invention can remove moisture more efficiently through the meshes of the filter in a shorter time by installing the filter on the target so that the base sheet is arranged parallel to the tilt direction. Furthermore, it was confirmed that regardless of the direction of the base sheet, it is difficult to remove moisture through the meshes of the filter at an angle of 0°.

[0058] [Deodorizing properties of adsorbent] <Odor test> Three types of samples were prepared, two of each, by impregnating mesoporous silica onto filter #120v using each of impregnation solutions 1 to 3, and then dried at 100°C for one hour. A gas containing 5 ppm ammonia and a gas containing 1 ppm hydrogen sulfide were passed through each sample, and the odor concentration was measured using a detector tube, and the time until the concentration reached the initial concentration was measured. The results are shown in Table 5 as the initial time. The speed of the odorous gas passing through the chamber was set to 1.0 m / sec. <Water washing regeneration test> After the odor test, the sample was removed and washed with water, and then held at room temperature for 1 minute so that the surface perpendicular to the filter thickness direction was at an angle of 60° to the horizontal. The moisture content at this time was 28% compared to immediately after washing, and the mesh penetration rate was 93%. The odor test was then carried out. The results are shown in Table 5 as the time after washing. As Reference Example 1, an initial, unused filter was washed with water and held at room temperature for 1 minute so that the surface perpendicular to the filter thickness direction was at an angle of 60° to the horizontal, and then the deodorization test was carried out.

[0059] [Table 5]

[0060] A comparison of the initial state with Reference Example 1 confirmed that the silica exhibited equivalent deodorizing performance against hydrogen sulfide and ammonia even in a water-containing state. The results of the odor test and the water-washing regeneration test confirmed that the most preferable filter member of the present invention is a filter impregnated with mesoporous silica containing 10 wt% Cu and 5 wt% Fe. Furthermore, it was confirmed that the filter exhibited excellent deodorizing properties because most of the pores were open, allowing ventilation even in a water-containing state immediately after washing.

[0061] The present invention has been described above by showing preferred embodiments, but it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. [Explanation of symbols]

[0062] 1 Filter member

Claims

1. A deodorizing filter that is installed in an installation object in a replaceable or non-replaceable manner, a filter member that is breathable along its thickness direction and includes a water-washable and reusable adsorbent; a holder that can hold the filter member so that a surface perpendicular to the thickness direction of the filter member forms an angle with respect to a horizontal plane when the filter member is installed on the installation target; A deodorizing filter comprising:

2. The filter member has 30 cells / inch ２ Over 600 cells / inch ２ 2. The deodorizing filter according to claim 1, having a plurality of through holes passing through the filter in the thickness direction, with the number of cells being the following:

3. 2. The deodorizing filter according to claim 1, wherein the filter member is held so that a surface perpendicular to the thickness direction of the filter member forms an angle of 5 degrees or more with respect to a horizontal plane.

4. The filter member is held so that the surface orthogonal to the thickness direction of the filter member is perpendicular to the horizontal plane, and in this case, the length of a perpendicular line drawn from the uppermost part of the filter member to the horizontal plane is defined as h ０ When the filter member is held so that a plane perpendicular to the thickness direction of the filter member forms an angle with respect to the horizontal plane, the length of a perpendicular line drawn from the uppermost part of the filter member to the horizontal plane is defined as h, and h<h ０ 2. The deodorizing filter according to claim 1, wherein the following relationship is satisfied:

5. 2. The deodorizing filter according to claim 1, wherein the filter member is formed so as to have a three-dimensional shape such as a rectangular parallelepiped or a cube.

6. When the vertical direction is the axial direction of the filter member, the angle θ formed by a plane perpendicular to the thickness direction of the filter member with respect to the horizontal plane, the thickness T of the filter member, and the length W of the filter member in the horizontal direction are such that: Arcsin((W ２ -T ２ ) / (W ２ +T ２ ))>θ≧Arctan(T / W) 6. The deodorizing filter according to claim 5, wherein the following relationship is satisfied:

7. 7. The deodorizing filter according to claim 1, wherein the water-washable and recyclable adsorbent is mesoporous silica doped with metal atoms.

8. A method for regenerating a deodorizing filter having a filter member including a water-washable regenerating adsorbent, The filter member is air permeable along the thickness direction, A method for regenerating a deodorizing filter, comprising washing the filter member with water and drying it while holding the filter member so that a surface perpendicular to the thickness direction of the filter member forms an angle with respect to a horizontal plane.

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