JPH10290921A - Deodorizing catalyst filter and deodorizing device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deodorizing catalyst filter having high deodorizing efficiency against a malodorous gas and excellent in durability and a deodorizing device using this filter and having high deodorizing efficiency. SOLUTION: A fibers ceramic structural sheet arranged in the inside of a ventillation port of a PTC ceramic structural body 1 having a lot of the ventillation ports is made into a fibrous ceramic structural body 2 with corrugation molding, this fibrous ceramic structural body 2 is made into a deodorizing catalyst filter having at least one kind of deodorizing catalyst and this filter is assembled between a fibrous pre-filter and a fan for sucking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deodorizing catalyst filter using a catalyst for deodorizing and purifying odors and exhaust gas (odors from toilets, garbage, etc.) discharged from homes and factories, and a deodorizing filter using the same. About the vessel.

[0002]

2. Description of the Related Art In recent years, with the modernization of buildings, the spread of air conditioning and heating, and the advancement of technology, as airtightness in rooms and automobiles has advanced, trace amounts of materials such as body odors, bad breath, and building materials that have not been noticed before have been generated. Often, the odor is also sensitive, and the harmful effect of causing discomfort to humans has frequently occurred. At the same time, environmental issues have become social issues, and in order to realize a comfortable and affluent living environment, it has become increasingly important to secure a more comfortable and safe air quality environment. There is a strong demand for a living environment free of odors on both sides. In addition, many women especially feel a strong dislike of the smell of the toilet after using it, and there are many demands for improvement in this respect.

[0003] In order to solve these problems,
Various deodorizing techniques and deodorizing devices have been developed mainly for toilet deodorizers, and are widely used. For example, most home deodorizers that are widely used at home use a physical adsorption method or an ozone oxidation method.

A deodorizer using the physical adsorption method is of a type in which an odor molecule is adsorbed on activated carbon or the like to deodorize. Further, the deodorizer using the ozone oxidation method is of a type that decomposes odor molecules using ozone and an ozone decomposition catalyst. As industrial deodorizers, there are those that use a catalytic oxidation method in addition to those of such a type. The deodorizer based on the catalytic oxidation method has a configuration in which a deodorizing catalyst is heated by an external heater or the like to activate the catalyst and decompose odor molecules.

[0005] In recent years, development of a deodorizing catalyst element or a deodorizing filter by coating a surface of a heater material with a deodorizing catalyst in order to enhance catalytic activity has already been made. For example, JP-A-7-185264 discloses a heater in which a catalyst is supported on a SiC honeycomb heater, and JP-A-8-150323 discloses a heater in which an intermediate layer is formed on the surface of a ceramic heater and then the catalyst is supported. A deodorizing device is disclosed.

[0006]

However, at present, various conventional deodorizers have the following problems.

[0007] In the deodorizer by the physical adsorption method, since the odor molecules are adsorbed on activated carbon and the like and deodorized, the service life is relatively short, which limits the application. Have been.

[0008] The deodorizer by the ozone oxidation method first degrades odor molecules using ozone and an ozone decomposition catalyst which are harmful to the human body, and thus lacks safety. Further, since an ozone generator (ozonizer) is required, the size of the apparatus tends to be large, and there is a great obstacle in terms of cost.
In addition, since the generation of ozone is hindered when the humidity is high, the deodorizing ability tends to fluctuate depending on the humidity, so that the use environment in which the device can be installed is limited.

In a deodorizer which decomposes odor molecules by activating the catalyst by heating the deodorizing catalyst with an external heater or the like, a heater for heating the catalyst is installed. The amount of heat required requires economic obstacles. Since it takes time to heat the catalyst until the catalyst is sufficiently activated, the deodorizing ability is reduced in the initial period of use, which also affects usability. Further, since the high temperature is applied, SOx and NOx are generated, which deteriorates the environment. Further, since the control unit of the heater tends to be complicated, there is a problem that the shape of the entire apparatus becomes large.

On the other hand, heaters with a deodorizing catalyst and a deodorizer using the same described in JP-A-7-185264 and JP-A-8-150323 have been developed to solve the above problems. It is.

However, since the catalyst and the heater material react with each other to cause a different phase or to deteriorate the electric resistance of the heater, the heater and the catalyst adversely affect each other. The characteristics are degraded and the deodorizing ability is attenuated. In order to avoid such a decrease in the deodorizing ability, it has been proposed to provide an intermediate layer between the heater and the catalyst, which is made of an inorganic material having the same thermal expansion coefficient as the material. However, at this stage, it is extremely difficult to specify what kind of material should be selected as the intermediate layer to achieve optimization, and a design with a high safety factor taking into account deterioration due to reaction with the heater, etc. There is a need to.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and provides a deodorizing catalyst filter having high deodorizing efficiency for malodorous gas and excellent in durability, and a deodorizer using the filter and having high deodorizing efficiency. The purpose is to provide.

[0013]

A deodorizing catalyst filter according to the present invention comprises a PTC ceramic structure having a large number of vents and a fibrous ceramic sheet disposed in the vents of the PTC ceramic structure. A fibrous ceramic structure formed by a gas processing method, and a structure in which the fibrous ceramic structure has at least one type of deodorizing catalyst. A container having an outlet, a fibrous pre-filter disposed downstream of the gas inlet, and a suction fan disposed downstream of the pre-filter; and further comprising the deodorizing catalyst filter. This is a configuration provided between the fibrous prefilter and the fan.

[0014] Thus, there is no adverse effect between the heater material and the catalyst, and a compact structure, a constant temperature can be quickly applied to the deodorizing catalyst filter to improve the deodorizing characteristics. The deodorizer having a high deodorizing efficiency can be provided by increasing the size.

[0015]

DETAILED DESCRIPTION OF THE INVENTION A deodorizing filter according to claim 1 of the present invention comprises a PTC ceramic structure having a large number of vents, and a fibrous ceramic sheet disposed in the vents of the PTC ceramic structure. And a fibrous ceramic structure formed by a corrugating method, and the fibrous ceramic structure has at least one kind of deodorizing catalyst.

In such a structure, a PTC ceramic honeycomb, which is a thermistor material having a positive characteristic, is used as a skeleton of the filter, and a fibrous ceramic structure is used as a carrier for the actual catalyst powder. As a result, there is no contact between the heater member and the catalyst. And PTC
Since ceramic is used for the skeleton, a certain temperature can be quickly applied to the deodorizing catalyst filter with a compact structure due to the characteristics of the PTC ceramic. further,
The fibrous honeycomb structure itself can easily carry many catalysts because of its large surface area, and has a large contact area with a malodorous gas, thereby improving the deodorizing efficiency.

The invention according to claim 2 is characterized in that γ-alumina,
Silica, aluminum silicate salt containing zeolite, titania, zirconia, etc. at least one kind of carrier powder on the surface of one or more types of catalytically active components are supported on the surface, since the carrier powder has a high specific surface area Has the effect that it can carry many catalytically active components.

The invention according to claim 3 is characterized in that oxides such as Mn, Cu, Fe, Zr, Pt, Pd,
It has a structure that supports metals such as Ag and Au, and can respond widely to S-based odors, N-based odors, and other odors due to the chemical nature of the oxidation promoting action of these oxides and metals. it can.

According to a fourth aspect of the present invention, there is provided a deodorizer comprising: a container having a gas inlet and a gas outlet; and a fibrous prefilter disposed in the container downstream of the gas inlet. A deodorizing catalyst filter according to claim 1 disposed downstream of the pre-filter, and a fan disposed downstream of the deodorizing catalyst filter. In this deodorizer, since the deodorizing catalyst filter according to any one of claims 1 to 3 of the present application is used, it is possible to efficiently decompose and remove odors emitted from homes.

In the deodorizing catalyst filter of the present invention,
The PTC ceramic structure of the deodorizing catalyst filter is PT
A step of mixing a methylcellulose-based thickener, an organic plasticizer, and water with the C ceramic powder, a step of kneading the mixture using a kneader, and a step of forming the mixture using a vacuum extruder after kneading. And firing at about 1300 ° C. after drying to obtain a PTC honeycomb structure.

Further, the fibrous ceramic structure is formed by a process of preparing a ceramic sheet mainly made of inorganic fibers such as alumina, alumina-silica, silica and the like and an inorganic binder such as clay using a papermaking method, A corrugating process is performed in the same manner as making a corrugated cardboard to form a corrugated sheet, and a flat plate and a corrugated plate are flattened to a corrugated plate and a step of obtaining a molded body by stacking the molded body at a temperature at which the inorganic binder is sintered. Obtained by a heat treatment step.

The deodorizing catalyst is a step of adding at least one kind of carrier powder such as alumina, silica, zeolite containing aluminum silicate salt, titania, zirconia and the like to water and dispersing and mixing; and adding Mn, Cu, Z
adding a predetermined amount of nitrate, hydrochloride, sulfate or the like such as r, Fe, or Pt, Pd, Ag, Au, etc., and dispersing;
It is obtained by a step of drying the water and a step of heat treatment at 350 ° C. to 550 ° C. after drying.

Further, the deodorizing catalyst is dispersed in water, an appropriate amount of the dispersion is poured into the opening of the fibrous ceramic structure, and the fibrous ceramic structure supporting the deodorizing catalyst is obtained by drying. Then, after forming an ohmic electrode on the PTC ceramic structure, the fibrous ceramic structure is placed in the opening of the PTC ceramic structure, thereby obtaining a deodorizing catalyst filter as a final product.

In the present invention, it is desirable to select a carrier powder having a large specific surface area, and it is possible to widely and uniformly disperse and support a catalytically active component such as Mn or Cu by the end of the selected carrier powder. it can. Also,
The catalytically active component is passed through a liquid phase in order to obtain an ultrafine particle layer, that is, dissolved in water using a catalytically active component, such as a nitric acid compound, as a starting material, and then carried on a carrier powder. Then, by making the catalytically active component ultrafine, the specific surface area of the powder itself increases, and the catalytic activity can be further increased. Mn, Cu, Fe, and Zr are particularly excellent at decomposing and removing sulfur-based malodorous gas even at a relatively low temperature, and Ag and Au are particularly excellent at removing nitrogen-based malodorous gas at a relatively low temperature. Excellent, Pt etc. can decompose and remove both odorous gases at 500 ° C or higher.

Furthermore, in the deodorizing catalyst filter of the present invention, if a fibrous ceramic structure is used as an actual catalyst carrier, since the fibrous ceramic structure has a fiber skeleton, the porosity and the structure of the structure itself can be reduced. The surface area can be increased. As a result, the catalyst can be easily impregnated and supported, and since a large amount can be uniformly supported, a high-performance deodorizing catalyst filter can be obtained by supporting the deodorizing catalyst on such a fibrous ceramic structure. Can be.

Here, the material composition of the PTC ceramic used for the PTC ceramic structure is substantially the same as that used for the PTC thermistor. That is, barium titanate (BaO.TiO ₂ ) is generally used as a main material, and an oxide of a rare earth element such as yttrium oxide (Y ₂ O ₃ ) is added thereto. A solid solution in which a part of Ba) is partially substituted with strontium (Sr) or lead (Pb) to form a solid solution is used.

The amount of the additive to be added to barium titanate is selected depending on the purpose of use of the PTC ceramic structure, but the amount of Y ₂ O ₃ is usually 0.1 to 0.3 mol.
%. When the addition amount of Y ₂ O ₃ is in such a range, the rate of change in the specific resistance of the PTC structure can be significantly improved. Further, by adding Sr, Tc (Curie point temperature) can be lowered (120 to −30 ° C.), and by adding Pb, Tc can be raised (120 to 250 ° C.).
° C).

In the case where the catalyst is directly supported on the PTC ceramic structure, when the temperature rises, the catalyst becomes active and the movement of the electrons becomes active, so that the PTC characteristic (the insulation resistance sharply increases at the Curie temperature and the current cannot pass) , As a result, the characteristic that the temperature becomes constant) disappears.
Not preferred. In order to prevent this, as described in the related art, it is possible to cope with the problem by providing an intermediate layer. However, not only is the selection and formation technique of the intermediate layer difficult, but also the catalyst and the PTC material are required. The properties may be adversely affected.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is an overall perspective view of a deodorizing catalyst filter according to Embodiment 1 of the present invention, FIG. 2 is an enlarged view of a main part of a portion A in FIG. 1, and FIG. 3 is a fine structure of a ceramic sheet of FIG. FIG. 4 and FIG. 4 are schematic diagrams of the flow-type experimental device.

In these figures, 1 is a PTC ceramic structure, 2 is a fibrous ceramic structure, 3 is a fibrous ceramic sheet, 4 is a deodorizing catalyst, 5 is a ceramic fiber,
Reference numeral 6 denotes an inorganic binder, 7 denotes a reaction tube, 8 denotes a deodorizing catalyst filter, 9 denotes an inlet of the reaction tube, 10 denotes a gas before processing, 11 denotes an outlet of the reaction tube, and 12 denotes a processing gas.

In the deodorizer having the above-described components, a method for producing the deodorizing catalyst 4, the fibrous ceramic structure 2, and the PTC ceramic structure 1, which contribute most to deodorization, will be described below in order.

(1) Method for producing deodorizing catalyst 4 Manganese nitrate hexahydrate and copper nitrate trihydrate were added to 30 g of γ-alumina, and Mn ₂ O ₃ and C
It was added so that the total amount was 10 parts by weight in terms of uO. At this time, the ratio of Mn ₂ O ₃ and CuO is CuO / (M
(n ₂ O ₃ + CuO) = 50 Wt%. Next, 50 g of water was added to the mixture, and the mixture was rotated and mixed in a 1-liter alumina pot containing zirconia balls of 10 mm in diameter. And take out the mixture into a magnetic crucible,
In an electric furnace, the heating rate at which water does not boil (for example, 50 ° C /
h) and heat-treated at 350 ° C. for 1 hour. Thereby, denitration was performed, and a Mn-Cu-based oxide deodorizing catalyst 4 having Mn ₂ O ₃ and CuO supported on the surface of γ-alumina was obtained.

Although the catalyst was mainly made of Mn-Cu, Fe, Pt and the like can be made in the same manner instead, and can be used for the deodorizing catalyst filter of the present invention. The same applies to the carrier powder, and any of titania, silica, zirconia, aluminum silicate, etc. may be used.However, it is more effective to use a carrier powder having a high acidity to decompose and remove alkaline malodorous gas. The lower the acidity, the more effective the decomposition and removal of acidic malodorous gases.

(2) Production method of fibrous ceramic structure 2 1000 g of 50% alumina-50% silica fiber and 1000 g of sericite clay were put into 600 liters of water and mixed. 100 to 200 g of pulp was added thereto, and 1 to 5 parts by weight (based on solid content) of an organic bond such as vinyl acetate was added to the total amount of fibers, pulp, and clay and mixed. Next, 3 to 7 parts by weight of aluminum chloride is added to the solid content as an inorganic coagulant, and 0.5 to 5 parts by weight of a polymer coagulant such as polyacrylamide is added to the solid content to cause coagulation. Was. This was paper-made using a fourdrinier machine to produce a ceramic sheet having a width of 350 mm, a thickness of 0.5 mm, and a length of 25 m. The sheet is formed into a corrugated sheet by a corrugation method, and a flat sheet and a corrugated sheet are stacked with a flat sheet to a corrugated sheet to form a molded article.
Heat treated at 50 ° C, width 45mm x length 5mm x depth 40
mm of fibrous ceramic structure 2 was obtained. The porosity of the material of the honeycomb structure 2 was about 80%.

As another production method, as in the production of the deodorizing catalyst 3, 10 g of (catalyst component / γ-alumina) = 10 parts by weight and 10 g of catalyst powder of CuO / (Mn ₂ O ₃ + CuO) = 50 Wt% are used. It was dispersed in 100 g of water to prepare a catalyst slurry. This catalyst slurry was injected into the opening of the structure using a syringe to carry the catalyst. Thereafter, drying was performed to obtain a fibrous ceramic structure 2 supporting a deodorizing catalyst. At this time, the supported amount of the catalyst was about 0.04 g / cc.

(3) Manufacturing method of PTC ceramic structure 1 Tc = 150 ° C. material made of barium titanate as a main raw material
For 10 kg of TC ceramic powder, methylcellulose
10 parts by weight of an organic thickener, 1 part by weight of an organic plasticizer,
25 to 30 parts by weight of water was added and dry mixed. Then
After kneading the compound mixed with the kneader with a three-stage roller, a honeycomb-shaped formed body was obtained using a vacuum extruder. This molded body was fired under the conditions of 1300 ° C.-1h, and 50 m in width.
A PTC ceramic structure 1 of mx 35 mm in length x 40 mm in depth was obtained. The size of the opening of the vent of the PTC ceramic structure 1 is 46 mm wide × 6 mm long × 40 depth.
mm. Then, an Ag paste is applied to both end surfaces of the PTC ceramic structure 1 where the holes are opened,
The final product was obtained by baking silver. When a direct current was passed through the PTC ceramic structure 1, the time required for the temperature to rise to about 150 ° C. was within 10 seconds.

The deodorizing characteristics of the deodorizing catalyst filter of the present invention including the components produced as described above were measured. The measuring method will be described with reference to FIG.

In this measurement method, the deodorizing catalyst filter 8 prepared in the above-described manner was set in the reaction tube 7, and the gas 10 before treatment (CH ₃ SH gas diluted to 15 ppm with air) was passed through the inlet 9 of the reaction tube 7. This is to measure the deodorizing ability while flowing and leaving the reaction tube outlet 11 through the deodorizing catalyst filter 8. One hour after the start of the experiment,
The concentration of the processing gas 12 from the outlet 11 of the reaction tube 7 was measured using a gas chromatograph.

As an experimental condition, the space velocity is SV = 250.
00 (1 / H) and SV = 50000 (1 / H) were set, and the reaction temperature was controlled to be maintained at 150 ° C. by applying a direct current to the deodorizing catalyst filter 8 directly. . As a result, 99.9% or more was obtained as the deodorization efficiency (= (gas concentration before treatment−gas concentration after treatment) / gas concentration before treatment × 100%). In addition, there was no abnormality in the deodorizing efficiency and PTC characteristics at all even after the continuous deodorizing test for 10 hours.

The space velocity varies depending on the target gas and the use conditions. However, a high space velocity increases the amount of gas to be treated, so that a lower space velocity is generally more advantageous for a catalyst. However, the deodorizing catalyst filter 8 according to the present invention can be used even at a space velocity of several hundred thousand by providing means for increasing the number of openings of the fibrous ceramic structure 2 or increasing the amount of catalyst carried. .

(Embodiment 2) FIG. 5 is a schematic cross-sectional view of a deodorizer using the deodorizing catalyst filter 8 manufactured in Embodiment 1 of the present invention.

In the figure, reference numeral 13 denotes a deodorizer according to the present embodiment, 14 denotes a box-shaped container made of metal, synthetic resin, or wood, etc., 14a denotes a gas inlet port opened in the container 14, 14b Is a gas outlet formed in the container 14 in communication with the gas inlet 14a, and 15 is the container 1
4, a fibrous pre-filter formed in a substantially rectangular parallelepiped shape having a vertical width of 50 mm, a horizontal width of 50 mm, and a depth of 2 to 3 mm, which is disposed at a distance of approximately 10 mm from the gas inlet 14a. The deodorizing catalyst filter 16 according to the first embodiment of the present invention, which is disposed approximately 10 mm away from the filter 15, is a suction filter disposed approximately 30 mm away from the deodorizing catalyst filter 8 in the container 14. Fan 17 is a deodorizing catalyst filter 8 and a fan 16
Is a control unit, 18 is an odor component contained in the air, and 19 is an odorless component contained in the purified gas purified by the deodorizer 13 and discharged from the gas discharge port 14b.

In such a configuration, the deodorizing catalyst filter 8 is heated and maintained at about 150 ° C. by energizing after a switch (not shown) provided at a predetermined portion of the deodorizer 13 is input. In addition, although not shown, around the deodorizing catalyst filter 8, a width of 45 mm, a width of 60 mm,
It is assumed that a fibrous heat insulating material formed in a substantially rectangular parallelepiped shape having a depth of 40 mm is wound.

The shape of the container body 14 is not limited to the box shape described above, but may be formed in a cylindrical shape or the like. Although not shown, a door for replacing the pre-filter 15 may be provided on the peripheral wall of the container 14.

The operation of the deodorizer 13 is as follows.
First, when the switch unit is turned on, the control unit 17 detects this and applies a predetermined DC current to the deodorizing catalyst filter 8 and the fan 16. As a result, the fan 16 is driven to draw air outside the deodorizer 13 from the gas suction port 14a, and the drawn air collects large dust and cotton dust by the pre-filter 15.

Further, the inhaled air flows through the deodorizing catalyst filter 8, and at this time, the offensive odor component 18 contained in the air is decomposed and removed by the deodorizing catalyst filter 8. The air thus purified is discharged to the outside from the gas discharge port 14b by the fan 16.

The deodorizer 13 shown in FIG.
m, and the container was filled with air containing 60 ppm of hydrogen sulfide as a target gas to test the deodorizing performance. As a result, it was confirmed that 99% or more of hydrogen sulfide was decomposed within 1 minute after filling with air. Further, the same result was obtained when the gas in the container was changed to methyl mercaptan or the like.

[0048]

As apparent from the above, according to the present invention,
Since the fibrous ceramic structure supporting the deodorizing catalyst is installed in the opening of the PTC ceramic structure, the PTC
The catalyst can be efficiently activated without any adverse effects or deterioration caused by directly supporting the catalyst on the ceramic, and the deodorizing and deodorizing of the offensive odor component can be performed quickly and with high deodorizing efficiency. This makes it possible to effectively decompose and remove odors (such as odors in toilets and garbage) emitted from homes and factories.

Further, since no catalytic substance such as ozone is used and the catalytic activity is exhibited by the decomposing action of the catalyst itself and the exothermic effect of the PTC ceramics, the safety is very high.

Furthermore, since an ozonizer or the like is not used, the cost and size of the deodorizer can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a deodorizing catalyst filter according to Embodiment 1 of the present invention.

FIG. 2 is an enlarged view of a main part of part A in FIG.

FIG. 3 is a microstructure diagram of the ceramic sheet of FIG. 2;

FIG. 4 is a schematic diagram of a flow-type experimental device.

FIG. 5 is a schematic cross-sectional view of a deodorizer using the deodorizing catalyst filter manufactured in Embodiment 1 of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 PTC ceramic structure 2 Fibrous ceramic structure 3 Fibrous ceramic sheet 4 Deodorizing catalyst 5 Ceramic fiber 6 Inorganic binder 7 Reaction tube 8 Deodorizing catalyst filter 9 Reaction tube entrance 10 Gas before treatment 11 Reaction tube outlet 12 Processing gas 13 Deodorizer 14 Container body 14a Gas inlet 14b Gas outlet 15 Prefilter 16 Fan 17 Control unit 18 Odor component 19 Odorless component

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yukinori Ikeda 1006 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] A PTC ceramic structure having a plurality of vents, and a fibrous ceramic structure formed by corrugating a fibrous ceramic sheet disposed in the plurality of vents of the PTC ceramic structure. And a fibrous ceramic structure having at least one type of deodorizing catalyst. 2. The deodorizing catalyst comprises one or more types of catalytically active components supported on the surface of at least one type of carrier powder such as aluminum silicate containing γ-alumina, silica, zeolite, titania and zirconia. The deodorizing catalyst filter according to claim 1, wherein: 3. Mn, Cu, Fe, Z as catalytically active components
The deodorizing catalyst filter according to claim 2, wherein an oxide such as r or a metal such as Pt, Pd, Ag, or Au is supported. 4. A container having a gas inlet and a gas outlet, a fibrous pre-filter disposed downstream of the gas inlet, and a suction fan disposed downstream of the pre-filter. A deodorizer comprising the deodorizing catalyst filter according to any one of claims 1 to 3 between a fibrous prefilter and a fan.