JPH1099690A - Deodorization catalyst and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide odor adsorption capability at ordinary temperature and enable odor components to be oxidation-decomposed by heating after adsorption by using a manganese-based oxide having decomposition activity of odor components, a carbon substance and zeolite with high adsorptivity. SOLUTION: The manganese-based oxide has the CuO:MnO radio of 2:1-1:10 and zeolite is ZSM-5 or β-zeolite and a carbon substance is graphite or activated carbon and the like. In this case if the carbon substance is not used, adsorptivity capacity of odor components decreases by about 70-80 percent compared with the case using the same. The mixture wt. ratio of the manganese-based oxide to the carbon substance is 10-20 and the mixture wt. ratio of the manganese- based oxide to the zeorite is 1:2-3. The manganese-based oxide is mixed with the carbon substance or with the zeolite and the carbon substance, pressure- formed and pulverized. The pulverized products are mixed with the zeolite or the manganese-based oxide and are formed to be the deodorization catalysts. Furthermore, heating the products by microwaves improves the decomposition activity of the manganese-based oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a deodorizing catalyst and a method for producing the same. More specifically, the present invention relates to a deodorizing catalyst for removing odorous substances from the atmosphere by alternately switching a catalyst temperature between a low temperature and a high temperature over time, and a method for producing the same.

[0002]

2. Description of the Related Art With the development of industry, the necessity of measures for preventing environmental pollution has long been called out, but in recent years the demand for more comfortable living environments has been increasing, and advanced There is a need for new environmental purification technology. In this environmental purification technology, in particular, the deodorization technology occupies an important position.

[0003] Deodorizing devices used in deodorizing technology include:
For example, an apparatus using activated carbon, ozone and an odor decomposition catalyst is known. In an apparatus using activated carbon, for example, the odor is contacted with the activated carbon by diffusing or circulating the odor into the micropores on the surface of the activated carbon formed into a honeycomb shape, and the odor component is physically adsorbed to the micropores to perform deodorization. I have.

In an apparatus using ozone, the odor component is decomposed by the oxidizing ability of ozone to perform deodorization, and the remaining odor component not decomposed by ozone is adsorbed by manganese oxide or the like to perform deodorization. ing. However, activated carbon deodorizes by adsorbing odor components, so the amount of adsorption increases as the use time elapses,
Eventually, the adsorption was saturated and the deodorizing effect was lost, and it was necessary to replace it, and the maintenance was troublesome. When left without replacement, this activated carbon becomes a source of odor. The odor decomposition catalyst has a very low decomposition rate at room temperature, and its deodorizing effect is mostly due to adsorption, and the deodorizing effect is reduced as in the case of the activated carbon.

On the other hand, an apparatus using ozone has a problem that the structure of the apparatus itself is complicated and the cost is high. In order to solve the above problem, for example, in Japanese Patent Application Laid-Open No. Hei 7-227420, the odor is adsorbed and deodorized by coating the surface of a substrate formed of a microwave-absorbing heat-generating inorganic material with an adsorption oxidation catalyst. It is described that a deodorizing element that has been adsorbed and deodorized is heated by microwaves to regenerate the deodorizing performance. That is, in this deodorizing element, the microwave-absorbing heat-generating inorganic material does not have catalytic activity, and the adsorption and oxidative decomposition of the odor component is performed by the adsorption oxidation catalyst.

[0006]

In the deodorizing element described in the above publication, ferrite is used as a microwave absorbing and heat-generating inorganic material. The adsorption oxidation catalyst is composed of an adsorbent and an oxidation catalyst, and a mixture of at least one of manganese oxide, zeolite, silica, and alumina is used as the adsorbent, and a platinum group metal element is used as the oxidation catalyst. ing.

However, the inventors of the present invention have found that when a mixture of manganese oxide and at least one of zeolite, silica and alumina is used as a deodorizing catalyst, its adsorbing power is reduced. Therefore, further improvement of the attraction force is desired.

[0008]

Here, if the odor component can be oxidized and decomposed by heating after the adsorption of the odor component, the deodorizing catalyst can be regenerated. Therefore, a deodorizing catalyst which has an adsorbing power at room temperature and can be regenerated by heating has been desired. The conditions required for the deodorizing catalyst include a large amount of adsorption at room temperature, a high oxidative decomposition activity during heating, and heat resistance, and the inventors of the present invention for a deodorizing catalyst satisfying these conditions include: It has been found that a deodorizing catalyst satisfying the above conditions can be obtained by using a carbon material together with a manganese-based oxide having an odor component decomposing activity and a highly adsorptive zeolite.

Thus, according to the present invention, there is provided a deodorizing catalyst characterized by containing a manganese-based oxide, a carbon material and zeolite. Further, according to the present invention, a manganese-based oxide and a carbon material, or a zeolite and a carbon material are mixed, pressure-formed and pulverized to obtain a pulverized product, and the pulverized product is mixed with zeolite or a manganese-based oxide. There is provided a method for producing a deodorizing catalyst, which comprises forming a deodorizing catalyst by molding.

[0010]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a manganese-based oxidation
MnO, MnO_TwoAnd Mn_TwoO _ThreeOxidation of
Gangan, copper oxide, iron oxide and nickel oxide
Of at least one selected metal oxide and manganese oxide
A composite oxide is exemplified. In addition, copper oxide (iron oxide and acid
Is the same for nickel oxide)
Is also good. These manganese-based oxides may be used alone or in combination.
They may be used in combination. Particularly preferred manganese acids
Are CuO: MnO = 2: 1 to 1:10, Fe_TwoO
_Three: MnO = 5: 1 to 1: 5.

Next, as the zeolite, ZSM-5,
Cu-ZSM-5, Pt-ZSM-5, β-zeolite, molecular sieves 3A, 4A and 13X, mordenite and the like. These zeolites may be used alone or in combination. Particularly preferred zeolites are ZSM-5, β-zeolite. Next, examples of the carbon substance include graphite, activated carbon, and carbon black. These carbon substances may be used alone or in combination. Here, when comparing the adsorption power of the odor component when the carbon material is not used and when it is used, it is reduced by about 70 to 80% when the carbon substance is used and when it is not used. Further, when the surface area of the deodorizing catalyst when not used was measured, it was found that the surface area was reduced by about 70 to 80% from the surface area calculated from solely the zeolite and the manganese-based oxide constituting the catalyst. Although the effect of this reduction is not clear, it is considered that the manganese-based oxide and the zeolite may cause some reaction to fill the pores of the zeolite. Thus, it has been found that by adding a carbon substance as in the present invention, it is possible to provide a deodorizing catalyst in which the surface area does not decrease and therefore the adsorption power does not decrease.

The mixing ratio (weight ratio) of the manganese-based oxide and the carbon material is preferably 50 to 5: 1, and 10 to 20:
1 is particularly preferred. Here, when the ratio of the manganese-based oxide is larger than 50: 1, the surface area decreases, which is not preferable. When the ratio of the manganese-based oxide is smaller than 5: 1, sufficient oxidation activity cannot be obtained. Not preferred.

The mixing ratio (weight ratio) of the manganese-based oxide and the zeolite is preferably 1: 1 to 5 and more preferably 1: 2 to 3
Is particularly preferred. Here, when the ratio of the manganese-based oxide is larger than 1: 1, the adsorptive power decreases, which is not preferable. When the ratio of the manganese-based oxide is smaller than 1: 5, sufficient oxidation activity cannot be obtained. It is not preferable. Furthermore, the deodorizing catalyst of the present invention is obtained by mixing a manganese-based oxide and a carbon material or a zeolite and a carbon material, press-molding and pulverizing to obtain a pulverized product, and mixing the zeolite or the manganese-based oxide with the pulverized product. It is preferably manufactured by molding. The reason why the manganese-based oxide or zeolite is preliminarily mixed with the carbon material is to prevent a decrease in the adsorbing power due to the direct contact between the manganese-based oxide and the zeolite. In addition, what was manufactured by previously mixing a manganese-based oxide and a carbon material is more preferable.

The deodorizing catalyst of the present invention can be formed into a powder, a pellet, a tablet, or a honeycomb according to the purpose of use. Also, when molding,
Known binders and the like may be added as long as the function of the deodorizing catalyst is not hindered. As described above, the deodorizing catalyst of the present invention is a manganese-based oxide having an odor component decomposing activity,
It is composed of zeolite having a high adsorptivity for odor components and a carbon material for improving the properties of both. Further, in the present invention,
By applying microwaves to the deodorizing catalyst, the deodorizing catalyst is heated, and as a result, the manganese-based oxide whose temperature has been increased has an improved decomposition activity. , The adsorption power is restored. Here, the microwave is not particularly limited, but is preferably applied periodically during the deodorization or after the deodorization catalyst is saturated with the odor component. When applying during deodorization, for example, frequency 1 to 10 GHz, output 100 to 10
The microwave of 00 W may be applied at intervals of 0.1 to 1 minute for 5 to 50 minutes. When the voltage is applied after saturation, for example, a microwave having a frequency of 1 to 10 GHz and an output of 100 to 1000 W may be applied.

Next, according to the production method of the present invention, a manganese-based oxide and a carbon material or a zeolite and a carbon material are mixed, pressure-formed and pulverized to obtain a pulverized product. Are mixed and molded to obtain a deodorizing catalyst. Here, the first and second pressure moldings are preferably performed under a pressure of 40 to 100 MPa. Known methods can be used for the pressure molding method and the pulverization method.

The deodorizing catalyst of the present invention can be used for a known household or commercial deodorizer. Here, FIG. 1 illustrates an example of an air purifier using the deodorizing catalyst of the present invention. In FIG. 1, 1 is a deodorizing catalyst, 2 is a ceramic holder, 3 is a magnetron, 4 is an intake port, 5 is a dust filter (pre-filter), 6 is a fan, 7 is a control circuit, 8 is a key input section, and 9 is a key input section. The outlet 10 indicates the air flow.

In the apparatus shown in FIG. 1, for example, when the fan 6 rotates, air flows from the intake port 4 to the exhaust port 9 via the dust filter 5 and the deodorizing catalyst 1. Here, large dust is removed from the air entering through the intake port 4 by the dust removal filter 5, and thereafter, the odor component is removed by passing through the deodorizing catalyst 1, and the air is discharged. When the user feels an odor, a signal is input to the key input unit 8 according to the degree of the odor. The magnetron 3
Operates to heat the deodorizing catalyst 1 and the performance of the catalyst is restored.

The control circuit 7 of the air purifier is configured, for example, as shown in FIG. That is, A /
A signal is sent to the CPU via the D converter, and at the same time, a signal is sent from the key input unit to the CPU. This signal is
By performing the operation in U, a control signal is sent to the magnetron via the amplifier. The magnetron performs an input based on the control signal sent thereto, and the deodorizing catalyst 1
Will be heated.

Here, in the CPU of the control circuit, a control signal is sent to the magnetron in a procedure as shown in the flowcharts of FIGS. 3 and 4, for example. FIG. 3 shows that the process returns to the start when there is no input in the key input unit, and ends when there is no input after a lapse of a predetermined time. In FIG. 4, when a weak to strong signal is input, a control signal is sent to the magnetron according to the procedure shown in the flowchart. That is, when input is made, the magnetron is turned on and off a predetermined number of times. When the temperature of the deodorizing catalyst reaches a predetermined temperature and when the magnetron is turned on a predetermined number of times, the input to the magnetron ends. FIG. 4 shows a case where a strong input is made,
When the medium and weak inputs are made, the times of the medium and weak magnetrons ON and OFF are set to t21 and t22, respectively.
Assuming that t31 and t32 are set, the ON time may be set so as to have a relationship of t11>t21> t31.

[0020]

【Example】

Test Example First, the adsorption power of zeolite was measured using the apparatus shown in FIG. 5 and using a gas containing isoprene as a model of the odor component under the following conditions. In FIG. 5, 11 is an air supply means, 12 is a flow meter, 13 is isoprene, 14 is isoprene ice cooling means, 15 is a microwave control means, 16 is a microwave oven, 17 is a deodorizing catalyst, 18 is a thermocouple, and 19 is a thermocouple. A temperature indicator, 20 is an autosampler, 21 is a gas chromatograph. The properties of the zeolite used are shown in Table 1 below.

Gas composition: 45 ppm isoprene / air dilution Gas flow rate: 600 ml / min Zeolite: 100 mg Analyzer: FID gas chromatograph (manufactured by Shimadzu Corporation) Column: Polapack Q, 1M column 150C

[0022]

[Table 1]

FIG. 6 shows the amount of adsorption over time. Table 2
Shows the amount of adsorption for 60 minutes.

[0024]

[Table 2]

Next, a manganese-based oxide shown in Table 3 below was used as a catalyst for exhibiting oxidative decomposition activity by heating odor components.

[0026]

[Table 3]

The zeolite shown in Table 1 and the manganese oxide powder shown in Table 3 were mixed at a weight ratio of 2: 1 and formed into a 20 mm doublet with a hydraulic press forming machine. After crushing to the size, the amount of adsorption for 60 minutes was measured in the same manner as in the case of the zeolite. The results are shown in Table 4 below.

[0028]

[Table 4]

As is apparent from Table 4, the adsorption amount is ZSM.
8.3 ml / g at -5 / A, 1 at β-zeolite / A
0.3 ml / g, which is lower than the original adsorption amount of zeolite. Further, when the surface areas of ZSM-5 / A and β-zeolite / A were measured, 231 m ² / g and 2
It was found to be 32 m ² / g, which was smaller than that of the original zeolite.

Further, X of ZSM-5 and ZSM-5 / A
The RD (X-ray diffraction) pattern was measured and is shown in FIGS. 7 (a) and 7 (c). As can be seen from this figure, while the maximum strength of zeolite alone is about 3000 cps, when the manganese-based oxide is added, it is reduced to about 1000 cps. From these facts, it is considered that a direct reaction between the zeolite and the manganese-based oxide causes a certain reaction to fill the pores of the zeolite.

Example 1 From the above test examples, graphite was added by the following method to prevent contact between zeolite and manganese-based oxide.
A deodorizing catalyst was produced. (1) A method in which ZSM-5, manganese-based oxide A and graphite are mixed and molded at once (2) ZSM-5 and graphite are mixed and molded, then pulverized, and then mixed with manganese-based oxide A and molded. (3) A method in which manganese-based oxide A and graphite are mixed and molded, pulverized, mixed with ZSM-5, and molded. ZSM-5, manganese-based oxide, and graphite are mixed in a ratio of 2: 1: 0.2 (weight ratio) was used. In addition, graphite is fixed carbon 83% -volatile content 2% -ash content 15%.
The particle size was +150 mesh 2% or less, -325 mesh 80% or more, and bulk specific gravity 0.4q / cc was used. The amount of adsorption was measured in the same manner as in the above Test Example.

The adsorption amounts of the deodorizing catalysts obtained by the above methods (1) to (3) were 8.5 ml / g and 11.8, respectively.
ml / g and 12.3 ml / g. From this result, it was found that the adsorption power can be improved by adding graphite. In addition, the methods (2) and (3) in which the zeolite and the manganese-based oxide are not directly mixed can provide a deodorizing catalyst having a higher adsorptive power, and among them, it has been found that the method (3) is excellent.

It should be noted that the ZSM-5 / ZSM-5 /
A: The XRD pattern of graphite was measured, and FIG.
(B). As can be seen from this figure, the maximum intensity was about 1500 cps.

Example 2 Manganese oxide A and graphite were previously mixed, molded and pulverized at a ratio of 10: 1, and the pulverized material and zeolite (β-zeolite, Cu-ZSM-5 and ZSM-5) were mixed at a ratio of 2: 1. Except for mixing and molding, the attraction force was measured in the same manner as in Example 1 above. The results are shown in Table 5 below.

[0035]

[Table 5]

From Table 5 above, it was possible to obtain a deodorizing catalyst having improved adsorption power and surface area as compared with the case where the original graphite was not contained. Here, since the surface area of graphite itself is small and the adsorptive power is low, it is considered that this improvement is due to the separation of zeolite and the manganese-based oxide by graphite.

[0037]

The deodorizing catalyst of the present invention is characterized by containing a manganese-based oxide, a carbon substance and a zeolite. For this reason, the odor component has an adsorption power at room temperature, and the odor component can be oxidized and decomposed by heating after the adsorption, so that a deodorization catalyst having a high adsorption power that can be easily regenerated can be obtained.

The deodorizing catalyst of the present invention is obtained by mixing a manganese-based oxide and a carbon material or a zeolite and a carbon material, press-forming and pulverizing to obtain a pulverized product, and mixing the zeolite or the manganese-based oxide with the pulverized product. Since the manganese-based oxide and the zeolite can be prevented from being in direct contact with each other by being molded and manufactured, a deodorizing catalyst having higher adsorption power can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an air purifier using the deodorizing catalyst of the present invention.

FIG. 2 is a configuration diagram of a control circuit of the air purifier of FIG.

FIG. 3 is a flowchart showing a procedure for sending a control signal to a magnetron.

FIG. 4 is a flowchart showing a procedure for sending a control signal to a magnetron.

FIG. 5 is a schematic configuration diagram of a device for estimating the amount of adsorption of a deodorizing catalyst.

FIG. 6 is a graph showing the amount of zeolite adsorbed over time.

FIG. 7 is an XRD pattern of ZSM-5, ZSM-5 / A / graphite and ZSM-5 / A.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Deodorizing catalyst 2 Ceramic holder 3 Magnetron 4 Intake port 5 Dust removal filter (pre-filter) 6 Fan 7 Control circuit 8 Key input section 9 Exhaust port 10 Air flow 11 Air supply means 12 Flow meter 13 Isoprene 14 Isoprene ice cooling means 15 Micro Wave control means 16 Microwave oven 17 Deodorizing catalyst 18 Thermocouple 19 Temperature indicator 20 Autosampler 21 Gas chromatograph

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takenori Hirano 1385-2 Kamisababuchi, Izumi-shi, Kagoshima Inside Kyushu Catalyst Research Co., Ltd.

Claims (8)

[Claims] 1. A deodorizing catalyst comprising a manganese-based oxide, a carbon material and zeolite. 2. The manganese-based oxide is at least one selected from manganese oxide or a composite oxide of manganese oxide and a metal oxide selected from copper oxide, iron oxide and nickel oxide.
The deodorizing catalyst according to claim 1, which is selected from species. 3. The deodorizing catalyst according to claim 1, wherein the carbon material is at least one selected from graphite, activated carbon, and carbon black. 4. The deodorizing catalyst according to claim 1, wherein the zeolite is at least one selected from ZSM-5 and β-zeolite. 5. A manganese-based oxide and a carbon material comprising:
The deodorizing catalyst according to any one of claims 1 to 4, which is contained in a weight ratio of 1 to 5: 1. 6. A manganese-based oxide and zeolite comprising:
The deodorizing catalyst according to any one of claims 1 to 5, which is contained in a weight ratio of 1 to 1: 5. 7. A deodorizing catalyst is obtained by mixing a manganese-based oxide and a carbon material or a zeolite and a carbon material, press-molding and pulverizing to obtain a pulverized product, mixing the zeolite or the manganese-based oxide with the pulverized product, The deodorizing catalyst according to any one of claims 1 to 6, which is obtained by molding. 8. A manganese-based oxide and a carbon material or a zeolite and a carbon material are mixed, pressure-molded and pulverized to obtain a pulverized product. The pulverized product is mixed with a zeolite or a manganese-based oxide, molded and deodorized. A method for producing a deodorizing catalyst, comprising obtaining a catalyst.