JP2000000471A - Waste gas treating catalyst, waste gas treatment and treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waste gas treating catalyst, a method of treating waste gas, and a waste gas treating device for particularly making harmless individually or simultaneously nitrogen oxides and chlorinated aromatic compounds such as dioxins contained in waste gas with respect to a technique of purifying waste gas discharged from various kinds of incinerators such as a municipal refuse incinerator, an industrial waste incinerator and a sludge incinerator. SOLUTION: This catalyst is the one consisting of a carrier consisting of single or compound oxide containing at least one or more kinds of elements selected from the group consisting of titanium(Ti), silicon(Si), aluminum(Al), zirconium(Zr), phosphor(P), and boron(B) and an active compound consisting of at least one kind of oxide of oxides of vanadium(V), tungsten(W), molybdenum(Mo), niobium(Nb), and tantalum(Ta) and is the one for decomposing harmful material in waste gas at 150-250 deg.C. The waste gas treating device using this catalyst is constituted of a dust collector 12 for removing smoke in waste gas 11 discharged from an incineration furnace and a catalytic device 13 for removing harmful material such as dioxins and highly condensed aromatic hydrocarbon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an incinerator for municipal waste,
Regarding technology for purifying exhaust gas discharged from various incinerators such as industrial waste incinerators and sludge incinerators, particularly, chlorinated aromatic compounds such as nitrogen oxides and dioxins contained in exhaust gas individually or The present invention relates to an exhaust gas treatment catalyst, an exhaust gas treatment method, and a treatment apparatus for detoxification at the same time.

[0002]

2. Description of the Related Art Exhaust gas discharged from various incinerators, such as municipal waste incinerators, industrial waste incinerators, and sludge incinerators, depends on the type of incineration target and the incineration conditions. , Nitrogen oxides, dioxins and P
Hazardous substances such as harmful chlorinated aromatic compounds represented by CBs and highly condensed aromatic hydrocarbons may be contained, causing damage to the human body, animals and plants as environmental hormones, and destroying the natural environment. As a serious social problem. For this reason, various methods for removing organic chlorine compounds such as dioxin have been proposed, such as activated carbon adsorption, thermal decomposition, and catalytic cracking. Among them, catalytic cracking using a catalyst includes ash treatment and wastewater treatment. It is considered that this is the most efficient removal method because it becomes unnecessary.

[0003] However, the catalyst in the catalytic cracking method proposed hitherto has a problem that a large amount of catalyst is required due to its low activity. Further, in order to decompose dioxins with a predetermined amount of catalyst, it is necessary to heat exhaust gas to a high temperature, and the cost required for heating becomes enormous. Further, there is a problem that the durability of the catalyst is lacked due to dusts containing nitrogen oxides, sulfur oxides, and heavy metals contained in the combustion exhaust gas. For example, an example of a conventionally proposed catalyst is a denitration catalyst using vanadium (V) oxide as an active metal and titanium (Ti) oxide as a carrier. In this case, the Ti oxide has a role of adsorbing ammonia, and the V oxide has a role of oxidizing the adsorbed ammonia with nitrogen oxide. If this denitration catalyst is used as it is as a catalyst for decomposing organic chlorine compounds such as dioxin, it cannot be said at present that it is necessarily a high-performance catalyst in terms of catalytic activity and durability, and has the above-mentioned problems. .

Conventionally, attempts have been made to adsorb and remove dioxins simultaneously with the removal of dust from exhaust gas. For example, when dioxins are removed together with dust using a dust remover (eg, a bag filter). Is
Since dioxins are adsorbed on the filter of the dust removing device, it is necessary to separately perform secondary treatment on the filter adsorbing the dioxins, which is troublesome. Similarly, when toxic substances including dioxins are melted at a high temperature, secondary processing of the melt is required,
There is a problem that the number of processing steps increases separately.

Further, dioxins are thermally decomposed at high temperatures in an incinerator, but when they pass through a gas cooling device and are dust-removed by a dust remover, they are regenerated in a low-temperature region of 400 ° C. or less. This may be a problem.

For this reason, it has been conventionally proposed to treat at a high temperature (300 to 500 ° C.) using platinum or the like as a catalyst (Japanese Patent Publication No. 4-63288). As described above, dioxins are regenerated, and decomposition treatment at lower temperature is desired.

In view of the above problems, the present invention improves the decomposition activity of harmful substances such as dioxins and highly condensed aromatic hydrocarbons in a low temperature range (especially 200 ° C. or lower), and reliably removes harmful substances in exhaust gas. An object of the present invention is to provide an exhaust gas treatment catalyst that decomposes, an exhaust gas treatment method, and a treatment apparatus.

[0008]

Means for Solving the Problems In view of the above problems, the present inventors have intensively studied to develop an inexpensive catalyst having high activity and excellent durability. As a result, the present inventors first analyzed the decomposition mechanism of an organic chlorine compound such as dioxin by a catalyst using various spectroscopic methods or the like, and elucidated the following catalyst mechanism.

[0009]

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[0010]

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[0011]

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[0012]

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Based on the above catalyst decomposition mechanism, it is considered that the conditions for a highly active and high performance catalyst must satisfy the following requirements. High specific surface area substance that easily adsorbs dioxin Solid acid substance that can cleave the OC, C-Cl bond of dioxin Oxidizing substance that oxidizes the cleaved intermediate product As a result of further study, from the viewpoint of improving the performance of organochlorine compounds using a carrier that forms a large amount of the specific surface area of the oxide and the amount of solid acid,
As a method for increasing the specific surface area and the amount of solid acid, it has been found that the above problems can be solved by converting an oxide such as Ti into a complex oxide. The present invention has been completed from such a viewpoint.

Based on such findings, the invention of the catalyst for treating exhaust gas according to claim 1 of the present invention relates to titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), B ( A carrier comprising a single or complex oxide containing at least one element selected from boron, and an oxide of vanadium (V), tungsten (W), molybdenum (Mo), niobium (Nd) or tantalum (Ta) And a catalyst comprising an active component comprising at least one kind of oxides, and decomposes harmful substances in exhaust gas at 150 to 250 ° C.

[0015] The invention of claim 2 is that the composite oxide of titanium is titanium and silicon, titanium and aluminum,
It is a composite oxide of at least one of titanium and zirconium, titanium and phosphorus, or titanium and boron.

[0016] The invention of a third aspect of the present invention relates to an exhaust gas treatment method.
A harmful substance in the exhaust gas is brought into contact with the catalyst of claim 1 or 2 to decompose the harmful substance in the exhaust gas.

According to a fourth aspect of the present invention, in the third aspect, the harmful substance in the exhaust gas is at least one chlorinated aromatic substance selected from dioxins, polychlorinated biphenyls, chlorobenzenes, chlorophenol and chlorotoluene. It is a group III compound.

The invention of claim 5 is characterized in that, in claim 4, nitrogen oxides are selectively reduced and decomposed in the presence of ammonia.

An exhaust gas treatment device according to claim 6 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, and a dust removal device for removing dust in exhaust gas, and an exhaust gas treatment device downstream of the dust removal device. A catalyst device having the exhaust gas treating catalyst according to claim 1 or 2 provided.

[Claim 7] is characterized in that in claim 6, means for introducing a basic substance is provided in the catalyst device.

[Claim 8] is a method according to claim 6 or 7, wherein the temperature of the exhaust gas introduced into the catalyst device is 150 to 2;
The temperature is set to 50 ° C.

Since the catalyst of the present invention uses a Ti-based composite oxide as a carrier, the specific surface area and the amount of solid acid can be greatly increased, and a large amount of catalyst is required for decomposing the organic chlorine compound. In addition, costs required for heating and the like can be reduced. Further, the catalyst of the present invention is excellent in durability against dusts containing sulfur oxides, heavy metals and the like contained in the combustion exhaust gas.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described, but the present invention is not limited thereto.

The invention of the catalyst for treating exhaust gas of the present invention relates to titanium (Ti), silicon (Si) and aluminum (A).
l), a support made of a single or composite oxide containing at least one or more elements selected from Zr (zirconium), P (phosphorus), and B (boron), and vanadium (V), tungsten (W), molybdenum ( Mo), niobium (N
d) or a catalyst comprising an active component comprising at least one oxide of tantalum (Ta) oxide;
It decomposes harmful substances in exhaust gas at 150 to 250 ° C.

Here, it is particularly preferable to use titanium as the carrier, and a titanium composite oxide is used as the carrier.
A catalyst for decomposing an organic chlorine compound in which at least one oxide of vanadium, tungsten or molybdenum oxide is supported as an active metal species has good catalytic activity.

In the present invention, in order to increase the specific surface area and the amount of solid acid of the decomposition catalyst, it is preferable to use a composite oxide-formed Ti oxide. Examples of the metal forming the composite oxide of Ti include silicon (Si) and aluminum (A
1), zirconium (Zr), phosphorus (P), boron (B) and the like. That is, a composite oxide such as Ti and Si, Ti and Al, Ti and Zr, Ti and P, and Ti and B can be used. Since any of these composite oxides hardly forms a sulfate, a stable structure can be maintained, and the specific surface area and the amount of solid acid can be increased.

Also, Ti and Si + Al, Ti and Si + Z
r, Ti and Si + P, Ti and Si + B, Ti and Al +
P, Ti and Al + B, Ti and Zr + P, Ti and Zr +
A ternary composite oxide such as B, Ti and P + B can be used.

The composition of the carrier in the case of the composite oxide is not particularly limited.
It is preferable that 30 to 5 parts by weight of an oxide such as silicon (Si), aluminum (Al), zirconium (Zr), phosphorus (P), and boron (B) is added to 0 to 95 parts by weight.

The reason why the specific surface area and the amount of solid acid increase due to the formation of the complex oxide is that a complex oxide in which another element having a different charge is inserted into stable tetravalent Ti has a new solid acid point due to charge compensation. Further, it is considered that since the particle diameter of the particles becomes smaller when the composite oxide is used, a higher specific surface area can be achieved.

The raw material of the element when forming the composite oxide may be any metal salt such as chloride, sulfate and nitrate. In the state of an aqueous solution, an aqueous alkali solution such as ammonia or sodium carbonate is added dropwise. Let it sink. Further, a composite hydroxide can be obtained by hydrolysis or the like using each of the metal alkoxide raw materials. The composite hydroxide cake formed by coprecipitation, hydrolysis, or the like is washed, dried, and calcined at a temperature in the range of 200 to 650 ° C. to obtain a composite oxide.

In the catalyst of the present invention, the composite oxide is used as a carrier.
Vanadium (V), Tungsten (W), Moly
Buden (Mo), niobium (Nb) or tantalum (Ta)
And at least these oxides as active metal oxides
Are also used by carrying one or more. All of the above oxides are oxidized
Dioxin that has the ability to adsorb and cleave _TwoMa
Can be oxidatively decomposed. In addition, any oxide
Also has excellent durability against sulfur compounds and heavy metals
Having. In particular, V oxide has excellent oxidation ability.

Although the components and the composition ratio of the catalyst composition according to the present invention are not particularly limited, a typical example is that the catalyst component is 5 parts per 100 parts by weight of a support made of a kind of oxide or composite oxide. In a one-component system such as vanadium oxide,
20 parts by weight are preferred. Similarly, in a binary system, vanadium pentoxide is 1 to 10 parts by weight and tungsten trioxide is 2 to 10 parts by weight.
25 parts by weight, 1-10 parts by weight of vanadium pentoxide and 2-25 parts by weight of molybdenum trioxide, 1-10 parts by weight of vanadium pentoxide and 0.5-5 parts by weight of niobium pentoxide Formulation is preferred. Similarly, in a ternary system, vanadium pentoxide is 1 to 10 parts by weight and tungsten trioxide is 1 to 10 parts by weight.
20 parts by weight and 1 to 20 parts by weight of molybdenum trioxide, 1 to 10 parts by weight of vanadium pentoxide, 1 to 10 parts by weight of tungsten trioxide and 0.5 to 5 parts by weight of niobium pentoxide. preferable. Similarly, in the quaternary system, 1-10 parts by weight of vanadium pentoxide and 1-2 parts by weight of tungsten trioxide are used.
It is preferable to use a mixture of 0 parts by weight, 1 to 20 parts by weight of molybdenum trioxide and 0.5 to 5 parts by weight of niobium pentoxide.
The metal oxide can be used alone, or an inorganic substance or the like can be added thereto, or can be used by being supported on a base material.

The catalyst used for the exhaust gas treatment may have any shape integrally molded, such as a pellet, a plate, a cylinder, a corrugate, and a honeycomb. Note that it is naturally preferable to increase the contact area with the gas,
The flow back pressure of the exhaust gas is undesirably increased depending on the degree of the packing density of the powder catalyst. As a countermeasure, it is particularly preferable to use, for example, a honeycomb-shaped molded product obtained by compressing a powder to a predetermined density without excessively reducing its specific surface area. In addition, when the bag filter contains a catalyst component to perform both dust removal and catalyst decomposition, a method of coating the bag filter with a powder component of the catalyst can be adopted.

The invention of the above catalyst for treating exhaust gas comprises titanium (Ti), silicon (Si), aluminum (Al),
A support made of a single or composite oxide containing at least one element selected from Zr (zirconium), P (phosphorus), and B (boron); vanadium (V), tungsten (W), molybdenum (Mo), A catalyst comprising an active component comprising at least one oxide of niobium (Nd) or tantalum (Ta) oxide;
In a temperature range of 50 ° C., harmful substances in exhaust gas can be decomposed.

Here, the harmful substances in the exhaust gas to be decomposed by the catalyst of the present invention include, in addition to nitrogen oxides, harmful chlorinated aromatic compounds represented by dioxins and PCBs, and aromatic compounds having a high degree of condensation. The term refers to harmful substances such as hydrocarbons and gaseous organic compounds, but is not limited to harmful substances (or environmental hormones) in exhaust gas that can be decomposed by the oxidation catalyst of the present invention.

Here, the above dioxins are a general term for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).
It is said to be generated in trace amounts during the combustion of chlorine compounds and certain organic chlorine compounds, and is a chemically colorless crystal. There are 75 types of PCDDs and 135 types of PCDFs, depending on the number of chlorines, from monochloride to octachloride. Of these, dibenzo-p-dioxin tetrachloride (T ₄ CDD) is the most common. It is known to be highly toxic. In addition, as harmful chlorinated aromatic compounds, in addition to dioxins, various organic chlorine compounds (for example, aromatic compounds such as phenol and benzene (for example, chlorobenzenes, chlorophenol and chlorotoluene) ), Chlorinated alkyl compounds, etc.) and must be removed from the exhaust gas.

PCBs (polychlorinated biphenyls)
Is a generic term for compounds in which several chlorine atoms are added to biphenyl, and there are isomers depending on the number and positions of substitution of chlorine, and 2,6-dichlorobiphenyl, 2,2′-dichlorobiphenyl, 2,3,5 -Trichlorobiphenyl and the like are typical, are known to be highly toxic, and may generate dioxins when incinerated, and must be removed from exhaust gas.

[0038] Highly condensed aromatic hydrocarbons are a general term for polynuclear aromatic compounds, which may contain one or more OH groups, are recognized as carcinogenic substances, and need to be removed from exhaust gas. .

In many manufacturing processes, exhaust gas containing, for example, gaseous organic compounds such as formaldehyde, benzene or phenol in addition to dust may be generated. These organic compounds are also environmental pollutants and significantly impair human health and need to be removed from the exhaust gas.

The nitrogen oxides to be treated in the present invention usually mean NO and NO ₂ , and also a mixture thereof.
It is also called NOx. However, the NOx often contains various oxidation numbers and unstable nitrogen oxides in addition to the above. Accordingly, x is not particularly limited, but is usually a value of 1 to 2. It becomes nitric acid, nitrous acid, etc. in rainwater or NO, or NO is said to be one of the main causes of photochemical smog, and is a harmful compound to the human body.

That is, by using the catalyst according to the present invention, the above-mentioned harmful substances such as nitrogen oxides, dioxins, and highly condensed aromatic hydrocarbons and gaseous organic compounds are catalytically reduced. Alternatively, it can be decomposed and detoxified. Here, dioxins in the exhaust gas of the above harmful substances, precursors of dioxins, PCB
Chlorinated aromatic compounds such as, high degree of condensation aromatic hydrocarbons,
Detoxification treatment is performed by oxidative decomposition of the oxidation catalyst of the present invention.

As for nitrogen oxides, a basic substance (for example, ammonia or the like) is present on the upstream side of the apparatus filled with the catalyst of the present invention, and detoxification treatment is performed by a reduction reaction.

FIG. 1 is a schematic diagram of an exhaust gas purifying apparatus using the above catalyst. As shown in FIG.
A dust removal device 12 for removing dust in exhaust gas 11 discharged from various incinerators such as a municipal waste incinerator, an industrial waste incinerator, and a sludge incinerator; a nitrogen oxide, a dioxin, and a highly condensed aromatic hydrocarbon A catalyst device 13 having the above-mentioned exhaust gas treatment catalyst for removing harmful substances such as
And a chimney 14 for discharging the removed exhaust gas to the outside. In the dust removal device 12, dust and solid dioxins in the exhaust gas can be collected,
This prevents deterioration of the catalyst device 13 and clogging of the catalyst.

The following shows the concentrations of nitrogen oxides and chlorinated aromatic compounds in the exhaust gas. The concentration of nitrogen oxides in the exhaust gas is 200 to 50 ppm by volume. The concentration of chlorinated aromatic compounds of dioxins in the exhaust gas is several tens mg to several μg / Nm ³ . In the present invention, the contact condition between the exhaust gas 11 and the catalyst is 20 to 2 Nm ³ / h / kg-catalyst (contact time: 4 to 0.4 seconds). The exhaust gas treatment temperature is 2
50-150 ° C. In this exhaust gas treatment temperature range,
Dioxins are not generated by resynthesis of the precursor of dioxins, which is a preferable treatment temperature.

Further, a dust removing device (eg, a bag filter)
Even when the exhaust gas is cooled to a low temperature when the treatment is performed in step 12, if the temperature is around 150 ° C., it becomes possible to treat the harmful substances in the exhaust gas without reheating. It should be noted that, in order to perform efficient collection in the dust removing device 12, even if cooling is performed using a cooling device on the upstream side of the dust removing device 12, even if reheating is performed before entering the catalytic device. It is preferable to limit the temperature to 250 ° C. where the regeneration rate of dioxins is low.

In the apparatus for purifying exhaust gas from an incinerator according to the present invention, the denitration and the removal of dioxins are carried out by one catalytic device 1.
3 can be performed simultaneously. In that case, ammonia may be introduced into the catalyst device 13 through an injection nozzle 15 for injecting, for example, ammonia as a basic substance.

The object to be treated according to the present invention includes, in particular, exhaust gas such as municipal waste and industrial waste. Such combustion exhaust gas usually contains dioxins represented by tetrachlorodibenzodioxin and pentachlorodibenzofuran in an amount of 1 to 100 ng TEQ / Nm ³ . Further, the exhaust gas contains a large amount of various organic chlorine compounds which are precursors of these dioxins. Regarding the emission of dioxin, the emission concentration is 0.1 ng TEQ /
The standard is set at Nm ³ or less, but these criteria can be satisfied by applying the catalyst of the present invention.

The conditions for removing organic chlorine compounds containing dioxins and the like in exhaust gas such as municipal waste and industrial waste using the catalyst of the present invention are preferably at a temperature of 100 to 25.
0 ° C., GHSV 1000 to 20000 h ⁻¹ , oxygen concentration 0.
It may be in the range of 1 to 21%, and it is also possible to add ammonia to simultaneously remove nitrogen oxides from exhaust gas.

[0049]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention.

Example 1 Titanyl sulfate (TiO ₄ )
The aqueous solution and the aqueous colloidal silica solution are mixed with TiO.
₂ : The mixture was mixed so that SiO ₂ = 90: 10, and the mixed aqueous solution was heated to 70 ° C. In the heated mixed aqueous solution,
An aqueous ammonia solution was dropped until pH = 7 to form a coprecipitate slurry. This slurry was stirred and aged at 70 ° C. for 2 hours, and then filtered and washed to obtain a cake. Next, the cake was dried at 100 ° C. and baked at 500 ° C. for 5 hours to obtain a TiO ₂ .SiO ₂ composite oxide. This composite oxide is referred to as composite oxide 1.
Ammonium paratungstate and ammonium metavanadate were dissolved in a methylamine aqueous solution such that WO ₃ was 8 parts by weight and V ₂ O ₅ was 5 parts by weight with respect to 100 parts by weight of the composite oxide 1, It was dropped on the Jo of the composite oxide by repeated kneading and drying WO ₃ and V ₂ O
₅ was carried. This sample was calcined at 500 ° C. for 5 hours to obtain a powder catalyst 1. 3 parts by weight of glass fiber as a binder, 3 parts by weight of kaolin, 3 parts by weight of cellulose acetate as an organic plasticizer, and aqueous ammonia were added to 100 parts by weight of the powder catalyst 1 and kneaded. The kneaded product was extruded to obtain an integrated honeycomb molded product having a pitch of 5.0 mm (wall thickness: 1.0 mm). The formed article was dried and fired at 500 ° C. for 5 hours to remove the organic plasticizer, thereby obtaining a honeycomb catalyst 1.

Example 2 In the preparation method of Example 1,
And instead of colloidal silica, aluminum sulfate or
The weight ratio of zirconium oxychloride to Ti
O_Two: Al_TwoO_Three= 90: 10, TiO_Two: ZrO_Two=
90:10, and added in the same manner as in the above composite oxide 1.
A composite oxide was obtained by the method. Complex oxidation of these composite oxides
Objects 2 and 3. Further, in the method of the first embodiment,
Ammonium titanyl sulfate aqueous solution without adding idal silica
To obtain a titanium hydroxide slurry.
Was. The slurry was washed with water and filtered to obtain a cake. The
Orthophosphoric acid or boric acid aqueous solution in weight ratio to the cake,
Each TiO_Two: P_TwoO_Five= 95: 5, TiO_Two: B
_TwoO _Three= 95: 5, kneading and drying.
The firing was performed at 500 ° C. for 5 hours. These composite oxides
Are composite oxides 4 and 5. The resulting composite oxide 2,
In the same manner as in Example 1 using 3, 4, and 5,
Powder catalysts 2, 3, 4 and 5 were obtained, and
Honeycomb catalysts 2, 3, 4, and 5 were obtained by the method.

Example 3 In the method for preparing a honeycomb catalyst of Example 1, the amount of colloidal silica added was TiO ₂ : SiO ₂ = 95: 5, 80:20, 60: 4 by weight ratio.
0, and composite oxides 6, 7, and 8 were obtained in the same manner as in Example 1. Powder catalysts 6, 7, and 8 were obtained from the obtained composite oxide in the same manner as in Example 1, and honeycomb catalysts 6, 7, and 8 were further obtained.

Example 4 In the method for preparing a honeycomb catalyst of Example 1, titanium tetrachloride was used instead of titanyl sulfate, and silane tetrachloride was used instead of colloidal silica, and TiO ₂ : SiO ₂ was used in a weight ratio. = 90:10 and mixed oxide 9 in the same manner as in Example 1.
I got In the method for preparing the honeycomb catalyst of Example 1, isopropoxytitanium was used instead of titanyl sulfate, and ethoxysilane was used instead of colloidal silica, and the weight ratio was TiO ₂ : SiO ₂ = 90: 10. And weighed. This mixed solution was heated to 80 ° C. and dropped into water heated to 80 ° C. to perform hydrolysis, thereby obtaining a precipitate slurry. This slurry was stirred and aged for 2 hours, washed and filtered to obtain a composite oxide 10 in the same manner as in Example 1. Using the composite oxides 9 and 10, powder catalysts 9 and 10 were obtained in the same manner as in Example 1, and honeycomb catalysts 9 and 10 were obtained.

[Example 5] In the method for preparing a honeycomb catalyst of Example 1, 8 parts by weight of MoO ₃ was used instead of ammonium paratungstate with respect to 100 parts by weight of the composite oxide 1 using ammonium molybdate. To obtain a powder catalyst 11 and a honeycomb catalyst 11 in the same manner as in Example 1.

Comparative Example 1 A comparative oxide 1, a comparative powder catalyst 1, and a comparative honeycomb catalyst were prepared in the same manner as in Example 1 except that colloidal silica was not added in the method for preparing the honeycomb catalyst 1 of Example 1. 1 was obtained.

[Catalyst Performance Evaluation Test] Measurement of specific surface area and solid acid content as physical property values of powdered catalysts 1 to 11 obtained in Examples 1 to 5 and comparative powdered catalyst 1 obtained in Comparative Example 1. Was done. The method for measuring the specific surface area and the amount of the solid acid is shown below. [Specific surface area measuring method] BET one-point adsorption method (nitrogen gas adsorption method). The measurement conditions are described below. Sample amount: 0.1 g Pretreatment condition: Purging under nitrogen atmosphere at 200 ° C for 2 hours Adsorption temperature: -196 ° C Desorption temperature: Room temperature Detector: Thermal conductivity detector (TCD) [Solid acid content measurement method] Pyridine adsorption By the thermal desorption method.
The measurement conditions are described below. Sample amount: 0.0125 g Pretreatment conditions: purged at 450 ° C. for 30 minutes in a helium atmosphere Adsorption temperature: 150 ° C. (pulse adsorption of 0.2 μl of pyridine repeatedly) Desorption conditions: 150 ° C. → 800 ° C. (heating rate: 30)
° C / min) Detector: Flame ion detector (FID) Table 1 below shows the measurement results.

[0057]

[Table 1]

Example 6 In the preparation method of Example 1, colloidal silica and aluminum sulfate were used in a weight ratio of TiO ₂ : SiO ₂ : Al ₂ O ₃ = 80:
The mixture was added in a ratio of 10:10, and a composite oxide composed of TiO ₂ , SiO _2, and Al ₂ O ₃ was obtained in the same manner as in the case of the composite oxide 1. This composite oxide is
It is assumed to be 12. V ₂ O ₅ (5% by weight) and WO were obtained in the same manner as in Example 1 using the obtained composite oxide 12.
₃ (8% by weight) was obtained, and a honeycomb catalyst 12 was obtained in the same manner as in Example 1.

Example 7 In the preparation method of Example 6, zirconium oxychloride was used in place of aluminum sulfate in a weight ratio of TiO ₂ : SiO ₂ : ZrO _2.
= 80: 10: 10, and the same operation was performed to obtain a honeycomb catalyst 13.

Example 8 In the preparation method of Example 6, zirconium oxychloride was used instead of colloidal silica in a weight ratio of TiO ₂ : Al ₂ O ₃ : ZrO.
₂ = 80: 10: 10, and the same operation was performed to obtain a honeycomb catalyst 14.

Example 9 In the preparation method of Example 6, orthophosphoric acid was replaced by aluminum phosphate in a weight ratio of TiO ₂ : SiO ₂ : P ₂ O ₅ = 85: 1.
0: 5, and the same operation was carried out.
I got

Example 10 In the preparation method of Example 6, boric acid was replaced by aluminum sulfate in a weight ratio of TiO ₂ : SiO ₂ : B ₂ O ₃ = 85: 10: 5.
And the same operation was performed to obtain a honeycomb catalyst 16.

Example 11 In the preparation method of Example 6, orthophosphoric acid was used instead of colloidal silica in a weight ratio of TiO ₂ : Al ₂ O ₃ : P ₂ O ₅ = 85:
Honeycomb catalyst was added in a ratio of 10: 5 and operated in the same manner.
17 was obtained.

Example 12 In the preparation method of Example 6, boric acid was used in place of colloidal silica in a weight ratio of TiO ₂ : Al ₂ O ₃ : B ₂ O ₃ = 85: 10:
5 and the same operation was carried out to obtain a honeycomb catalyst 18.

[Examples 13 and 14] In the preparation methods of Examples 11 and 12, zirconium oxychloride was used in a weight ratio of TiO ₂ : ZrO ₂ : P instead of aluminum sulfate.
₂ O ₅ = 85: 10: 5 ratio, TiO ₂ : ZrO ₂ :
B ₂ O ₃ was added at a ratio of 85: 10: 5, and the same operation was performed to obtain honeycomb catalysts 19 and 20.

Example 15 In the preparation method of Example 9, boric acid was added in place of colloidal silica by weight ratio.
TiO ₂ : P ₂ O ₅ : B ₂ O ₃ = 90: 5: 5 respectively
And the same operation was performed to obtain a honeycomb catalyst 21.

Example 16 1 of Complex Oxide 1 of Example 1
5 parts by weight of V ₂ O ₅ , N by using niobium oxide instead of ammonium paratungstate
The catalyst was supported so that b ₂ O ₅ became 1% by weight, and the same operation as in the example was carried out to obtain a honeycomb catalyst 22.

Example 17 1 of composite oxide 1 of Example 1
Further, ammonium molybdate is further added to ₅ parts by weight of V ₂ O ₅ , WO ₃ is 5% by weight, M
The catalyst was supported so that oO ₃ became 5% by weight, and the same operation as in Example 1 was performed to obtain a honeycomb catalyst 23.

Example 18 1 of Complex Oxide 1 of Example 1
With respect to 00 parts by weight, niobium oxide was added to V ₂
A honeycomb catalyst 24 was obtained in the same manner as in Example 1 by supporting O ₅ at 5% by weight, WO ₃ at 5% by weight, and Nb ₂ O ₅ at 1% by weight.

Example 19 1 of composite oxide 1 of Example 1
With respect to 00 parts by weight, ammonium molybdate and niobium oxide were used in place of ammonium paratungstate, and V ₂ O ₅ was 5% by weight, MoO ₃ was 5% by weight, Nb
₂ O ₅ is supported at 1% by weight, and the honeycomb catalyst 25
I got

[Example 20] 1 of composite oxide 1 of Example 1
Further, ammonium molybdate and niobium oxide were added to ₅ parts by weight of V ₂ O ₅ and WO ₃
5% by weight, 5% by weight of MoO ₃ and 1% by weight of Nb ₂ O ₅ , and a honeycomb catalyst 26 was obtained in the same manner as in Example 1.

[Evaluation of Catalytic Activity] Using the honeycomb catalysts 1 to 26 obtained in Examples 1 to 5 and the comparative honeycomb catalyst 1 obtained in Comparative Example 1, a catalytic decomposition test of dioxin using actual exhaust gas was performed. . The test conditions and the composition of the actual exhaust gas are shown below. Temperature: 200 ° C. Gas amount: 152 Nm ³ / h Catalyst shape: 150 mm × 150 mm × 750 mm (1
6.9 L) GHSV: 9000 h ^-1 Superficial velocity: 3.3 m / s [Gas composition] Inlet dioxin concentration: 5 ng-TEQ / m ³ NH ₂ O: 20% O ₂ : 10% N ₂ : Balance The dioxin concentration before and after the catalyst was indicated by a TEQ value, and the analysis was performed using a mass spectrometer after exhaust gas was suctioned and subjected to various concentration steps. The dioxin concentrations at the inlet and the outlet of the catalytic reactor were measured, and from the following formula (1), dioxins (polychlorinated dibenzo-p-
The decomposition rates (η) of dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured. The test conditions and test results are shown in "Table 2" and "Table 3".

[0073]

Decomposition rate (η) = (1−DXN concentration at outlet / DXN concentration at inlet) × 100 (1)

[0074]

[Table 2]

[0075]

[Table 3]

From these results, it was found that by bringing the actual exhaust gas into contact with the developed catalyst, the dioxin concentration at the catalyst outlet could be 0.1 ng-TEQ / m ³ N or less in any case.

[0077]

As described above, according to claim 1 of the present invention, titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), and B ( (B), a support made of a single or composite oxide containing at least one element selected from the group consisting of vanadium (V), tungsten (W), and molybdenum (M
o), a catalyst comprising an active component comprising at least one oxide of oxides of niobium (Nd) and tantalum (Ta), which decomposes harmful substances in exhaust gas at 150 to 250 ° C. Also, the decomposition and denitration rates of dioxins are good.

According to a second aspect of the present invention, in the first aspect, the composite oxide of titanium is at least one of titanium and silicon, titanium and aluminum, titanium and zirconium, titanium and phosphorus, or titanium and boron. Since it is one kind of composite oxide, the amount of solid acid increases,
A synergistic effect is exhibited by the composite oxide, and decomposition of dioxins and the like becomes possible.

According to the invention of claim 3, the harmful substance in the exhaust gas is brought into contact with the catalyst of claim 1 or 2, so that the harmful substance in the exhaust gas can be decomposed.

The invention of claim 4 is characterized in that the harmful substances in the exhaust gas are particularly dioxins, polychlorinated biphenyls,
At least one chlorinated aromatic compound selected from chlorobenzenes, chlorophenol and chlorotoluene can be decomposed.

According to a fifth aspect of the present invention, in the fourth aspect, in the presence of ammonia, a nitrogen oxide can be further selectively reduced to perform a decomposition treatment.

The invention of claim 6 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, which is provided on a downstream side of the dust removal device for removing dust in the exhaust gas. The catalyst device having the catalyst for treating exhaust gas according to claim 1 or 2, wherein the amount of solid acid is increased so that dioxins in the exhaust gas, precursors of dioxins, chlorinated aromatic compounds such as PCBs, and highly condensed aromatics are contained. Oxidative decomposition of group hydrocarbons becomes possible.

According to the invention of claim 7, in claim 6, since means for introducing a basic substance is provided in the catalyst device, denitration becomes possible by addition of a basic gas.
Combined decomposition of both becomes possible.

The invention according to claim 8 is the invention according to claim 6 or 7, wherein the temperature of the exhaust gas introduced into the catalyst device is set to 150 ° C.
Since the temperature is set to ２５０250 ° C., harmful substances can be decomposed even at a low temperature.

Further, even if a catalyst device in which a catalyst for denitration and a catalyst for oxidative decomposition of a chlorinated aromatic compound and a high-condensation aromatic hydrocarbon are separated is arranged in parallel, the exhaust gas can be decomposed.

Further, by combining the catalyst device according to the present invention and the low-temperature dust removing device, it becomes possible to remove chlorinated aromatic compounds such as dioxins and high-condensation aromatic hydrocarbons in exhaust gas and to remove denitration. Dust, HC
It is possible to remove harmful substances such as l, SOx, and heavy metals at the same time.

As described above, according to the present invention, a catalyst using a Ti-based composite oxide as a carrier can greatly increase the specific surface area and the amount of solid acid, so that an organic chlorine compound such as dioxin can be easily produced. , And can be decomposed and removed efficiently.
And, by using the catalyst of the present invention, harmful organic chlorine compounds can be removed to a low concentration that does not cause environmental problems and the like,
It is of great industrial significance.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of an exhaust gas treatment device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Exhaust gas 12 Dust removing device 13 Catalytic device 14 Chimney 15 Ammonia injection nozzle

[Procedure amendment]

[Submission date] May 21, 1999 (1999.5.2
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

Based on such findings, the invention of the catalyst for treating exhaust gas according to claim 1 of the present invention relates to titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), B ( A carrier comprising a single or complex oxide containing at least one element selected from boron, and an oxide of vanadium (V), tungsten (W), molybdenum (Mo), niobium (Nd) or tantalum (Ta) in at least one such from the active ingredient an oxide Rutotomoni a specific surface area of 100 m ² / g or more of
A catalyst having a solid acid content of 0.36 mmol / g or more;
Decomposes harmful substances in exhaust gas at 150 to 250 ° C. Further, in claim 1, the specific surface area is 1
00 to 150 m ² / g, and the solid acid content is 0.36 to 0.45.
It is characterized in that it is a mmol / g catalyst .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

According to a third aspect of the present invention, in the first aspect, the carrier constituting the composite oxide is titanium (Ti) and ketone.
I (Si), Titanium (Ti) and Aluminum (A
l), titanium (Ti) and zirconium (Zr), titanium
(Ti) and phosphorus (P), titanium (Ti) and boron (B)
A binary composite oxide consisting of any one of
And features. [Claim 4] The invention according to claim 1
And titanium (Ti), silicon (Si) and aluminum
(Al), titanium (Ti), silicon (Si) and zircon
Nitride (Zr), titanium (Ti), silicon (Si) and
(P), titanium (Ti), silicon (Si) and boron
(B), titanium (Ti), aluminum (Al) and phosphorus
(P), titanium (Ti), aluminum (Al) and boro
(B), titanium (Ti), zirconium (Zr) and
(P), titanium (Ti), zirconium (Zr) and
Ron (B), Titanium (Ti), Phosphorus (P) and Boron
(B), a ternary composite oxide composed of any one of
It is characterized by being.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

[0016] The invention of a method for treating exhaust gas according to claim 5 is:
A harmful substance in the exhaust gas is brought into contact with the catalyst according to any one of claims 1 to 4 to decompose the harmful substance in the exhaust gas.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

The invention according to claim 6 is the invention according to claim 5, wherein the harmful substance in the exhaust gas is at least one chlorinated aromatic substance selected from dioxins, polychlorinated biphenyls, chlorobenzenes, chlorophenol and chlorotoluene. It is a group III compound.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

[0018] invention [Claim 7] The method of claim 6, in the presence of ammonia, characterized by decomposing nitrogen oxides selectively reduced to.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

An exhaust gas treatment device according to claim 8 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, and a dust removal device for removing dust and soot in the exhaust gas, and a downstream side of the dust removal device. A catalyst device comprising the exhaust gas treatment catalyst according to any one of claims 1 to 4 provided.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction contents]

[Claim 9 ] is characterized in that in claim 8 , a means for introducing a basic substance is provided in the catalyst device.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

A tenth aspect of the present invention is the method according to the eighth or ninth aspect, wherein the temperature of the exhaust gas introduced into the catalyst device is set to 150 to 2
The temperature is set to 50 ° C.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0077

[Correction method] Change

[Correction contents]

[0077]

As described above, according to claim 1 of the present invention, titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), and B ( (B), a support made of a single or composite oxide containing at least one element selected from the group consisting of vanadium (V), tungsten (W), and molybdenum (M
o), niobium (Nd) or tantalum (at least one of <br/> from the active ingredient consisting of oxides Rutotomoni of oxides of Ta), and a specific surface area of 100 m ² / g or more solid
A catalyst having an acid amount of 0.36 mmol / g or more;
Since the harmful substances in the exhaust gas are decomposed at 250 ° C., the decomposition and denitration rates of dioxins can be improved even at low temperatures.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0078

[Correction method] Change

[Correction contents]

According to a third aspect of the present invention, in the first aspect, the carrier constituting the composite oxide is titanium (Ti).
And silicon (Si), titanium (Ti) and aluminum (A
l), titanium (Ti) and zirconium (Zr), titanium
(Ti) and phosphorus (P), titanium (Ti) and boron (B)
Is a two-component composite oxide consisting of any one of the following ,
Since the amount of the solid acid increases, a synergistic effect of the composite oxide is exhibited, and decomposition of dioxins and the like becomes possible. Further, according to the invention of claim 4, in claim 1,
The carrier constituting the composite oxide is titanium (Ti) and silicon
(Si) and aluminum (Al), titanium (Ti)
Silicon (Si), zirconium (Zr), titanium (T
i), silicon (Si), phosphorus (P), titanium (Ti)
Silicon (Si) and boron (B), titanium (Ti) and aluminum
Minium (Al) and phosphorus (P), titanium (Ti) and aluminum
Minium (Al) and boron (B), titanium (Ti) and di
Ruconium (Zr) and phosphorus (P), titanium (Ti) and di
Ruconium (Zr), boron (B), titanium (Ti)
One of phosphorus (P) and boron (B)
Since it is a component-based composite oxide and the amount of solid acid increases,
Synergistic effects of composite oxides are demonstrated, and dioxins
Can be decomposed.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0079

[Correction method] Change

[Correction contents]

According to the invention of claim 5 , since the harmful substance in the exhaust gas is brought into contact with the catalyst according to any one of claims 1 to 4, the harmful substance in the exhaust gas can be decomposed.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0080

[Correction method] Change

[Correction contents]

According to the invention of claim 6 , the harmful substances in the exhaust gas are particularly dioxins, polychlorinated biphenyls,
At least one chlorinated aromatic compound selected from chlorobenzenes, chlorophenol and chlorotoluene can be decomposed.

[Procedure amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0081

[Correction method] Change

[Correction contents]

[0081] invention [Claim 7], in claim 6, in the presence of ammonia, can be decomposed by further selective reduction of nitrogen oxides.

[Procedure amendment 15]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The invention of claim 8 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, which is provided on a downstream side of the dust removal device for removing dust in the exhaust gas. A catalyst device comprising the exhaust gas treatment catalyst according to any one of claims 1 to 4, wherein the amount of solid acid is increased to thereby increase the amount of dioxins, dioxin precursors, and chlorinated aromatic compounds such as PCBs in the exhaust gas. Thus, oxidative decomposition of aromatic hydrocarbons with a high degree of condensation becomes possible.

[Procedure amendment 16]

[Document name to be amended] Statement

[Correction target item name] 0083

[Correction method] Change

[Correction contents]

According to the ninth aspect of the present invention, since a means for introducing a basic substance is provided in the catalyst device in the eighth aspect , denitration becomes possible by addition of a basic gas.
Combined decomposition of both becomes possible.

[Procedure amendment 17]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The invention of claim 10 is the invention of claim 8 or 9
In the above, the temperature of the exhaust gas introduced into the catalyst device is adjusted to 15
Since the temperature is set to 0 to 250 ° C., it is possible to decompose harmful substances even at a low temperature. ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 20, 1999 (1999.9.2)
0)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

Based on such findings, the invention of the catalyst for treating exhaust gas according to claim 1 of the present invention provides titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), and B (phosphorus). a carrier comprising a double engagement oxide Ru is selected from boron), vanadium (V), tungsten (W), molybdenum (Mo), niobium (N b) or at least one kind of oxide out of oxides of tantalum (Ta) And a specific surface area of 100
m ² / g or more and a solid acid amount of 0.36 mmol / g or more, an exhaust gas treatment catalyst for decomposing harmful substances in exhaust gas at 150 to 250 ° C., wherein the composite oxide
Is composed of titanium (Ti) and silicon (Si)
Aluminum (Al), titanium (Ti) and silicon (S
i) and zirconium (Zr), titanium (Ti) and silicon
(Si) and phosphorus (P), titanium (Ti) and silicon (S
i) and boron (B), titanium (Ti) and aluminum
(Al) and phosphorus (P), titanium (Ti) and aluminum
(Al) and boron (B), titanium (Ti) and zirconium
(Zr) and phosphorus (P), titanium (Ti) and zirconium
(Zr) and boron (B), titanium (Ti) and phosphorus
(P) and boron (B)
It is a complex oxide .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Deleted

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

[0016] The invention of claim 2 is an exhaust gas treatment method,
A harmful substance in the exhaust gas is brought into contact with the catalyst of claim 1 to decompose the harmful substance in the exhaust gas.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

[0017] invention [Claim 3], according to claim 2, harmful substances dioxin in said exhaust gas, polychlorinated biphenyls, chlorobenzenes, at least one chlorinated aromatics selected from chlorophenol and chlorotoluene It is a group III compound.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

The invention according to claim 4 is characterized in that in claim 2 , nitrogen oxides are selectively reduced and decomposed in the presence of ammonia.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

An exhaust gas treatment device according to claim 5 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, and a dust removal device for removing dust in the exhaust gas, and an exhaust gas treatment device downstream of the dust removal device. A catalyst device having the exhaust gas treatment catalyst according to claim 1 provided.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction contents]

[Claim 6 ] is characterized in that in claim 5 , a means for introducing a basic substance is provided in the catalyst device.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

[Claim 7] is a method according to claim 5 or 6, wherein the temperature of the exhaust gas introduced into the catalyst device is 150 to 2;
The temperature is set to 50 ° C.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

The invention of the catalyst for treating exhaust gas of the present invention relates to titanium (Ti), silicon (Si) and aluminum (A).
l), a support made of a single or composite oxide containing at least one or more elements selected from Zr (zirconium), P (phosphorus), and B (boron), and vanadium (V), tungsten (W), molybdenum ( Mo), niobium (N
b ) or a catalyst comprising an active component comprising at least one oxide of oxides of tantalum (Ta);
It decomposes harmful substances in exhaust gas at 150 to 250 ° C.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction contents]

The invention of the above catalyst for treating exhaust gas comprises titanium (Ti), silicon (Si), aluminum (Al),
A support made of a single or composite oxide containing at least one element selected from Zr (zirconium), P (phosphorus), and B (boron); vanadium (V), tungsten (W), molybdenum (Mo), niobium (N b), or a catalyst comprising an active ingredient consisting of at least one oxide of an oxide of tantalum (Ta), 150-2
In a temperature range of 50 ° C., harmful substances in exhaust gas can be decomposed.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0050

[Correction method] Change

[Correction contents]

[ Reference Example 1] Titanyl sulfate (TiO ₄ )
The aqueous solution and the aqueous colloidal silica solution are mixed with TiO.
₂ : The mixture was mixed so that SiO ₂ = 90: 10, and the mixed aqueous solution was heated to 70 ° C. In the heated mixed aqueous solution,
An aqueous ammonia solution was dropped until pH = 7 to form a coprecipitate slurry. This slurry was stirred and aged at 70 ° C. for 2 hours, and then filtered and washed to obtain a cake. Next, the cake was dried at 100 ° C. and baked at 500 ° C. for 5 hours to obtain a TiO ₂ .SiO ₂ composite oxide. This composite oxide is referred to as composite oxide 1.
Ammonium paratungstate and ammonium metavanadate were dissolved in a methylamine aqueous solution such that WO ₃ was 8 parts by weight and V ₂ O ₅ was 5 parts by weight with respect to 100 parts by weight of the composite oxide 1, It was dropped on the Jo of the composite oxide by repeated kneading and drying WO ₃ and V ₂ O
₅ was carried. This sample was calcined at 500 ° C. for 5 hours to obtain a powder catalyst 1. 3 parts by weight of glass fiber as a binder, 3 parts by weight of kaolin, 3 parts by weight of cellulose acetate as an organic plasticizer, and aqueous ammonia were added to 100 parts by weight of the powder catalyst 1 and kneaded. The kneaded product was extruded to obtain an integrated honeycomb molded product having a pitch of 5.0 mm (wall thickness: 1.0 mm). The formed article was dried and fired at 500 ° C. for 5 hours to remove the organic plasticizer, thereby obtaining a honeycomb catalyst 1.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

[Reference example2]Reference exampleIn the preparation method 1
And instead of colloidal silica, aluminum sulfate or
The weight ratio of zirconium oxychloride to Ti
O_Two: Al_TwoO_Three= 90: 10, TiO_Two: ZrO_Two=
90:10, and added in the same manner as in the above composite oxide 1.
A composite oxide was obtained by the method. Complex oxidation of these composite oxides
Objects 2 and 3. Also,Reference exampleIn the first method, the roller
Ammonium titanyl sulfate aqueous solution without adding idal silica
To obtain a titanium hydroxide slurry.
Was. The slurry was washed with water and filtered to obtain a cake. The
Orthophosphoric acid or boric acid aqueous solution in weight ratio to the cake,
Each TiO_Two: P_TwoO_Five= 95: 5, TiO_Two: B
_TwoO _Three= 95: 5, kneading and drying.
The firing was performed at 500 ° C. for 5 hours. These composite oxides
Are composite oxides 4 and 5. The resulting composite oxide 2,
Using 3,4,5Reference examplePowder by the same method as in 1.
Powder catalysts 2, 3, 4, and 5,Reference exampleSame as 1
Honeycomb catalysts 2, 3, 4, and 5 were obtained by the method.

[Procedure amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction contents]

Reference Example 3 In the method for preparing a honeycomb catalyst of Reference Example 1, the amount of colloidal silica added was TiO ₂ : SiO ₂ = 95: 5, 80:20, 60: 4 by weight ratio.
0, and composite oxides 6, 7, and 8 were obtained in the same manner as in Reference Example 1. Reference from the obtained composite oxide
In the same manner as in Example 1, powder catalysts 6, 7, and 8 were obtained, and further, honeycomb catalysts 6, 7, and 8 were obtained.

[Procedure amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0053

[Correction method] Change

[Correction contents]

Reference Example 4 In the method for preparing a honeycomb catalyst of Reference Example 1, titanium tetrachloride was used in place of titanyl sulfate, and silane tetrachloride was used in place of colloidal silica, and the weight ratio was TiO ₂ : SiO _2. = 90:10, and mixed oxide 9 in the same manner as in Reference Example 1.
I got In the method for preparing a honeycomb catalyst of Reference Example 1, isopropoxytitanium was used instead of titanyl sulfate, and ethoxysilane was used instead of colloidal silica, so that TiO ₂ : SiO ₂ = 90: 10 by weight. And weighed. This mixed solution was heated to 80 ° C. and dropped into water heated to 80 ° C. to perform hydrolysis, thereby obtaining a precipitate slurry. This slurry was stirred and aged for 2 hours, washed and filtered to obtain a composite oxide 10 in the same manner as in Reference Example 1. Powder catalysts 9 and 10 were obtained using the composite oxides 9 and 10 in the same manner as in Reference Example 1, and honeycomb catalysts 9 and 10 were obtained.

[Procedure amendment 16]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Change

[Correction contents]

[ Reference Example 5] In the method for preparing a honeycomb catalyst of Reference Example 1, 8 parts by weight of MoO ₃ was used instead of ammonium paratungstate with respect to 100 parts by weight of the composite oxide 1. To obtain a powder catalyst 11 and a honeycomb catalyst 11 in the same manner as in Reference Example 1.

[Procedure amendment 17]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction contents]

[0055] In Comparative Example 1 process for the preparation of honeycomb catalyst 1 in Example 1, without the addition of colloidal silica, ginseng
In the same manner as in Example 1 , Comparative Oxide 1, Comparative Powder Catalyst 1, and Comparative Honeycomb Catalyst 1 were obtained.

[Procedure amendment 18]

[Document name to be amended] Statement

[Correction target item name] 0056

[Correction method] Change

[Correction contents]

[Catalyst Performance Evaluation Test] Measurement of specific surface area and solid acid content as physical property values of powdered catalysts 1 to 11 obtained in Reference Examples 1 to 5 and Comparative Powdered Catalyst 1 obtained in Comparative Example 1. Was done. The method for measuring the specific surface area and the amount of the solid acid is shown below. [Specific surface area measuring method] BET one-point adsorption method (nitrogen gas adsorption method). The measurement conditions are described below. Sample amount: 0.1 g Pretreatment condition: Purging under nitrogen atmosphere at 200 ° C for 2 hours Adsorption temperature: -196 ° C Desorption temperature: Room temperature Detector: Thermal conductivity detector (TCD) [Solid acid content measurement method] Pyridine adsorption By the thermal desorption method.
The measurement conditions are described below. Sample amount: 0.0125 g Pretreatment conditions: purged at 450 ° C. for 30 minutes in a helium atmosphere Adsorption temperature: 150 ° C. (pulse adsorption of 0.2 μl of pyridine repeatedly) Desorption conditions: 150 ° C. → 800 ° C. (heating rate: 30)
° C / min) Detector: Flame ion detector (FID) Table 1 below shows the measurement results.

[Procedure amendment 19]

[Document name to be amended] Statement

[Correction target item name] 0058

[Correction method] Change

[Correction contents]

Example 6 In the preparation method of Reference Example 1 , colloidal silica and aluminum sulfate were added in a weight ratio of TiO ₂ : SiO ₂ : Al ₂ O ₃ = 80:
The mixture was added in a ratio of 10:10, and a composite oxide composed of TiO ₂ , SiO _2, and Al ₂ O ₃ was obtained in the same manner as in the case of the composite oxide 1. This composite oxide is
It is assumed to be 12. V ₂ O ₅ (5% by weight) and WO were obtained in the same manner as in Reference Example 1 using the obtained composite oxide 12.
₃ (8 wt%) to obtain a supported powder catalyst 12, further participation
A honeycomb catalyst 12 was obtained in the same manner as in Example 1 .

[Procedure amendment 20]

[Document name to be amended] Statement

[Correction target item name] 0067

[Correction method] Change

[Correction contents]

Example 16 1 of Composite Oxide 1 of Reference Example 1
5 parts by weight of V ₂ O ₅ , N by using niobium oxide instead of ammonium paratungstate
The catalyst was supported so that b ₂ O ₅ became 1% by weight, and the same operation as in the example was carried out to obtain a honeycomb catalyst 22.

[Procedure amendment 21]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

Example 17 1 of Composite Oxide 1 of Reference Example 1
Further, ammonium molybdate is further added to ₅ parts by weight of V ₂ O ₅ , WO ₃ is 5% by weight, M
The catalyst was supported so that the content of oO ₃ became 5% by weight, and the same procedure as in Reference Example 1 was carried out to obtain a honeycomb catalyst 23.

[Procedure amendment 22]

[Document name to be amended] Statement

[Correction target item name] 0069

[Correction method] Change

[Correction contents]

Example 18 1 of Composite Oxide 1 of Reference Example 1
With respect to 00 parts by weight, niobium oxide was added to V ₂
A honeycomb catalyst 24 was obtained by carrying out operation in the same manner as in Reference Example 1 by supporting O ₅ at 5% by weight, WO ₃ at 5% by weight, and Nb ₂ O ₅ at 1% by weight.

[Procedure amendment 23]

[Document name to be amended] Statement

[Correction target item name] 0070

[Correction method] Change

[Correction contents]

Example 19 1 of Composite Oxide 1 of Reference Example 1
With respect to 00 parts by weight, ammonium molybdate and niobium oxide were used in place of ammonium paratungstate, and V ₂ O ₅ was 5% by weight, MoO ₃ was 5% by weight, Nb
₂ O ₅ is supported at 1% by weight, and the honeycomb catalyst 25
I got

[Procedure amendment 24]

[Document name to be amended] Statement

[Correction target item name] 0071

[Correction method] Change

[Correction contents]

Example 20 1 of Composite Oxide 1 of Reference Example 1
Further, ammonium molybdate and niobium oxide were added to ₅ parts by weight of V ₂ O ₅ and WO ₃
And 5% by weight of MoO ₃ and 1% by weight of Nb ₂ O ₅ , and a honeycomb catalyst 26 was obtained in the same manner as in Reference Example 1.

[Procedure amendment 25]

[Document name to be amended] Statement

[Correction target item name] 0072

[Correction method] Change

[Correction contents]

[Evaluation of Catalytic Activity] A dioxin catalytic decomposition test was performed using actual exhaust gas using the above- obtained honeycomb catalysts 1 to 26 and the comparative honeycomb catalyst 1 obtained in Comparative Example 1. The test conditions and the composition of the actual exhaust gas are shown below. Temperature: 200 ° C. Gas amount: 152 Nm ³ / h Catalyst shape: 150 mm × 150 mm × 750 mm (1
6.9 L) GHSV: 9000 h ^-1 Superficial velocity: 3.3 m / s [Gas composition] Inlet dioxin concentration: 5 ng-TEQ / m ³ NH ₂ O: 20% O ₂ : 10% N ₂ : Balance The dioxin concentration before and after the catalyst was indicated by a TEQ value, and the analysis was performed using a mass spectrometer after exhaust gas was suctioned and subjected to various concentration steps. The dioxin concentrations at the inlet and the outlet of the catalytic reactor were measured, and from the following formula (1), dioxins (polychlorinated dibenzo-p-
The decomposition rates (η) of dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured. The test conditions and test results are shown in "Table 2" and "Table 3".

[Procedure amendment 26]

[Document name to be amended] Statement

[Correction target item name] 0077

[Correction method] Change

[Correction contents]

[0077]

As described above, according to claim 1 of the present invention, titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), B ( a carrier comprising a double engagement oxide Ru is selected from boron), vanadium (V), tungsten (W), molybdenum (Mo), niobium (N b) or at least one kind of oxide out of oxides of tantalum (Ta) A catalyst having a specific surface area of 100 m ² / g or more and a solid acid amount of 0.36 mmol / g or more,
An exhaust gas treatment catalyst for decomposing harmful substances in exhaust gas at 150 to 250 ° C., wherein the carrier comprises the composite oxide
But titanium (Ti), silicon (Si) and aluminum
(Al), titanium (Ti), silicon (Si) and zirconi
(Zr), titanium (Ti), silicon (Si) and phosphorus
(P), titanium (Ti), silicon (Si) and boron
(B), titanium (Ti), aluminum (Al) and phosphorus
(P), titanium (Ti), aluminum (Al) and boro
(B), titanium (Ti), zirconium (Zr) and
(P), titanium (Ti), zirconium (Zr) and
Ron (B), Titanium (Ti), Phosphorus (P) and Boron
(B), a ternary composite oxide composed of any one of
Since it is, the amount of the solid acid is increased, synergistic due composite oxide
The effect is exhibited, and the decomposition and denitration rate of dioxins etc. are reduced.
It will be good.

[Procedure amendment 27]

[Document name to be amended] Statement

[Correction target item name] 0078

[Correction method] Deleted

[Procedure amendment 28]

[Document name to be amended] Statement

[Correction target item name] 0079

[Correction method] Change

[Correction contents]

According to the second aspect of the present invention, the harmful substances in the exhaust gas are brought into contact with the catalyst of the first aspect, so that the harmful substances in the exhaust gas can be decomposed.

[Procedure amendment 29]

[Document name to be amended] Statement

[Correction target item name] 0080

[Correction method] Change

[Correction contents]

The invention according to claim 3 is characterized in that the harmful substances in the exhaust gas are particularly dioxins, polychlorinated biphenyls,
At least one chlorinated aromatic compound selected from chlorobenzenes, chlorophenol and chlorotoluene can be decomposed.

[Procedure amendment 30]

[Document name to be amended] Statement

[Correction target item name] 0081

[Correction method] Change

[Correction contents]

According to the invention of claim 4 , in the case of claim 2 , in the presence of ammonia, nitrogen oxides can be further selectively reduced to carry out decomposition treatment.

[Procedure amendment 31]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The invention of claim 5 is an exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, which is provided on a downstream side of the dust removal device for removing dust in the exhaust gas. Since the catalyst device having the catalyst for treating exhaust gas according to claim 1 is used, dioxins in the exhaust gas, precursors of dioxins, chlorinated aromatic compounds such as PCBs, and highly condensed aromatic carbons are increased by increasing the amount of solid acid. Oxidative decomposition of hydrogen becomes possible.

[Procedure amendment 32]

[Document name to be amended] Statement

[Correction target item name] 0083

[Correction method] Change

[Correction contents]

According to the invention of claim 6 , in claim 5 , since means for introducing a basic substance is provided in the catalyst device, denitration becomes possible by addition of a basic gas.
Combined decomposition of both becomes possible.

[Procedure amendment 33]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

[0084] invention [Claim 7], according to claim 5 or 6, 150 the temperature of the exhaust gas introduced into the catalytic converter
Since the temperature is set to ２５０250 ° C., harmful substances can be decomposed even at a low temperature.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01J 23/28 B01J 23/30 A 23/30 27/199 A 27/199 32/00 ZAB 32/00 ZAB B01D 53/36 G (72) Inventor Megumi Shida 1-8-1, Koura, Kanazawa-ku, Yokohama-shi, Kanagawa Prefecture Mitsubishi Heavy Industries, Ltd. Yokohama Research Laboratory (72) Inventor Shigeru Nojima 4-2-2 Kanon Shinmachi, Nishi-ku, Hiroshima, Hiroshima Prefecture No. Mitsubishi Heavy Industries, Ltd. Hiroshima Laboratory (72) Inventor Kozo Iida 4-22, Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture Mitsubishi Heavy Industries, Ltd. Hiroshima Laboratory F-term (reference) 2E191 BA00 BA12 BA13 BC01 BD12 BD13 4D048 AA06 AA11 AA17 AA30 AB02 AB03 AC04 BA03Y BA06Y BA07X BA07Y BA08Y BA09X BA24X BA24Y BA26X BA26Y BA27X BA27Y BA42X BA42Y 4G069 AA03 AA08 BA01A BA01B BA02A BA02B BA04A BA04B BA05A BA05B BA10B BA21B BA29B BB01A BB01B BB04B BB05B BB06A BB06B BB10C BB20C BC16A BC50A BC50B BC50C BC51A BC54A BC54B BC55A BC56A BC59A BC59C BC60A BC60B BD01B BD03A BD03B BD05A BD06B BD07A BD07B BE08B BE32B CA02 CA04 CA08 CA10 CA11 CA13 CA19 EA18 EC03Y FA02 FB06 FB09 FB30 FB57 FB67

Claims (8)

[Claims] 1. A single or composite oxide containing at least one element selected from titanium (Ti), silicon (Si), aluminum (Al), Zr (zirconium), P (phosphorus), and B (boron). And vanadium (V), tungsten (W), molybdenum (M
o) a catalyst comprising an active component comprising at least one oxide of oxides of niobium (Nd) or tantalum (Ta), and decomposing harmful substances in exhaust gas at 150 to 250 ° C. Exhaust gas treatment catalyst. 2. The composite oxide according to claim 1, wherein the composite oxide of titanium is at least one of titanium and silicon, titanium and aluminum, titanium and zirconium, titanium and phosphorus, or titanium and boron. A catalyst for decomposing organochlorine compounds, characterized in that: 3. An exhaust gas treatment method comprising contacting a harmful substance in an exhaust gas with the catalyst of claim 1 to decompose the harmful substance in the exhaust gas. 4. The method according to claim 3, wherein the harmful substance in the exhaust gas is at least one chlorinated aromatic compound selected from dioxins, polychlorinated biphenyls, chlorobenzenes, chlorophenol and chlorotoluene. Exhaust gas treatment method. 5. The exhaust gas treatment method according to claim 4, wherein nitrogen oxides are selectively reduced and decomposed in the presence of ammonia. 6. An exhaust gas treatment device for purifying exhaust gas discharged from an incinerator, comprising: a dust removal device for removing dust in the exhaust gas; and a dust removal device provided downstream of the dust removal device.
An exhaust gas treatment device comprising: a catalyst device having the exhaust gas treatment catalyst according to the above. 7. The exhaust gas treatment apparatus according to claim 6, wherein a means for introducing a basic substance is provided in the catalyst device. 8. The exhaust gas according to claim 6, wherein the temperature of the exhaust gas introduced into the catalyst device is 150 to 250.
An exhaust gas treatment device characterized by a temperature of ° C.