KR20220145935A - Catalyst for ammonia oxidation, and method for producing the same - Google Patents

Abstract

The present invention relates to a catalyst for ammonia oxidation and a method for producing the same, wherein an active material including Pt, V_2O_5 and WO_3 is supported in a TiO_2 carrier. The catalyst of the present invention may comprise 0.1 to 3 wt% of Pt, 2 to 3 wt% of V, and 1 to 2 wt% of W, based on 100 wt% of the TiO_2 carrier in atom-based content. Accordingly, an excellent conversion rate of ammonia and selectivity of nitrogen can be ensured, even within a range of a temperature of less than 400℃.

Description

Catalyst for ammonia oxidation, and method for producing the same

The present invention relates to a catalyst for oxidation of ammonia and a method for preparing the same, and more particularly, to a catalyst for oxidation of ammonia for an SCR catalyst system and a method for preparing the same for application to an SCR catalyst system.

Nitrogen oxide mainly refers to NO and NO ₂ and is denoted as NOx. NO is a colorless, odorless gas that is easily converted to yellowish-brown NO ₂ in the atmosphere. It also causes acid rain, and produces various oxidizing agents such as O ₃ , HCHO, and PAN (peroxyacetyl nitrate) to cause secondary pollution and photochemical smog. N ₂ O is the second most emitted component after CO ₂ and CH ₄ , one of the representative greenhouse gases, and its global warming effect is 310 times higher than that of CO ₂ molecules.

Accordingly, various technologies for removing nitrogen oxides have been developed. Among them, selective catalytic reduction (SCR) is the only technology that can remove more than 90% of nitrogen oxides emitted from fixed sources.

In SCR, a reducing agent (ammonia-based: ammonia, ammonia water, urea/non-ammonia-based: HC, CO, H ₂ ) is injected into the exhaust gas and mixed with air or steam in advance, and then this mixed gas is mixed with the upper part of the reactor operated at 250 ~ 450 ℃. It is a method of decomposing nitrogen oxides into nitrogen and water by passing them through a catalyst layer. In particular, ammonia SCR is the most widely used because of its high reactivity with nitrogen oxides.

Theoretically, when NH ₃ :NOx = 1:1, ammonia slip does not occur in the SCR reaction, but in the case of the rear end of the SCR of an automobile, ammonia slip occurs irregularly due to a change in temperature conditions depending on the engine load. . Therefore, in order to control such ammonia slip, an ammonia oxidation catalyst (AOC) is applied and operated.

However, in the case of the noble metal-based AOC currently used, it shows a high ammonia removal efficiency, but has a disadvantage in that the nitrogen selectivity is too low. If the nitrogen selectivity of AOC is low, ammonia is oxidized and NOx is regenerated and discharged to the outside.

Accordingly, it is still necessary to develop an AOC having excellent nitrogen selectivity so that NOx is not regenerated while showing excellent ammonia oxidation performance.

On the other hand, as a similar prior literature thereto, Republic of Korea Patent Publication No. 10-0785523 is presented.

Republic of Korea Patent Publication No. 10-0785523 (2007.12.06)

In order to solve the above problems, an object of the present invention is to provide a catalyst for ammonia oxidation having excellent nitrogen selectivity so that NOx is not regenerated while showing excellent ammonia oxidation performance and a method for preparing the same.

However, the above purpose is illustrative, and the technical spirit of the present invention is not limited thereto.

One aspect of the present invention for achieving the above object relates to a catalyst characterized in that an active material comprising Pt, V ₂ O ₅ and WO ₃ is supported on a TiO ₂ carrier, wherein the catalyst is a TiO ₂ carrier by weight of 100 It relates to a catalyst for the oxidation of ammonia comprising 0.1 to 3% by weight of Pt, 2 to 3% by weight of V and 1 to 2% by weight of W in an atomic basis relative to %, more preferably, the catalyst for oxidation of ammonia is TiO ₂ It may include 0.2 to 0.5% by weight of Pt, 2.5 to 3% by weight of V, and 1 to 2% by weight of W with respect to 100% by weight of the carrier.

In one aspect, the ammonia oxidation catalyst may have an ammonia conversion rate of 80% or more and a nitrogen selectivity of 80% or more in a temperature range of 330 to 380°C.

In one aspect, the ammonia oxidation catalyst may have an ammonia conversion rate of 95% or more and a nitrogen selectivity of 90% or more at 350°C.

In one aspect, the catalyst for ammonia oxidation may have a carbon monoxide conversion of 80% or more in a temperature range of 330 to 380°C.

In addition, another aspect of the present invention comprises the steps of: a) preparing a catalyst precursor by supporting an active material precursor including a platinum precursor, a vanadium precursor and a tungsten precursor on a TiO ₂ carrier in a co-impregnation method; and b) drying and calcining the catalyst precursor to prepare a catalyst, wherein the catalyst contains 0.1 to 3 wt% of Pt, ₂ to 3 wt% of V, and It relates to a method for preparing a catalyst for oxidation of ammonia comprising 1 to 2% by weight of W.

In addition, another aspect of the present invention is an SCR catalyst; and a catalyst for oxidation of ammonia coated on a predetermined region of one end of the SCR catalyst.

In the catalyst for ammonia oxidation according to the present invention, an active material including Pt, V ₂ O ₅ and WO ₃ is supported on a TiO ₂ carrier, and 0.1 to 3 wt% of Pt in an atomic basis based on 100 wt% of the TiO ₂ carrier, By including 2 to 3% by weight of V and 1 to 2% by weight of W, it is possible to secure excellent ammonia oxidation performance and nitrogen selectivity.

Specifically, the catalyst for ammonia oxidation according to the present invention may have an ammonia conversion rate of 80% or more and a nitrogen selectivity of 80% or more in a temperature range of 330 to 380° C., in particular, Pt _0.3 V ₃ W ₂ /TiO ₂ or Pt _0.3 In the case of V ₃ W ₁ /TiO ₂ , the ammonia conversion rate may be 90% or more and the nitrogen selectivity may be 80% or more in the temperature range of 330 to 380°C, and the ammonia conversion rate at 350°C is 95% or more and the nitrogen selectivity is 95 % or more.

1 is an example 1 (Pt _0.3 V ₃ W ₂ /TiO ₂ ) of the catalyst prepared in ammonia conversion, carbon monoxide conversion, and nitrogen oxide production evaluation data.
2 is an evaluation data of ammonia conversion rate, carbon monoxide conversion rate and nitrogen oxide production amount of a catalyst (Pt _0.3 /SCR) directly supporting Pt on a commercial catalyst.
3 is prepared in Example 1 (Pt _0.3 V ₃ W ₂ /TiO ₂ ), Example 2 (Pt ₃ V ₃ W ₂ /TiO ₂ ) and Comparative Example 1 (Pt _0.03 V ₃ W ₂ /TiO ₂ ), respectively These are the evaluation data of the ammonia conversion rate, carbon monoxide conversion rate, and nitrogen oxide production amount of the catalyst.
4 and 5 are Example 1 (Pt _0.3 V ₃ W ₂ /TiO ₂ ), Example 3 (Pt _0.3 V ₂ W ₂ /TiO ₂ ), Comparative Example 2 (Pt _0.3 W ₂ /TiO ₂ ), Comparative Examples 3 (Pt _0.3 V ₁ W ₂ /TiO ₂ ) and Comparative Example 4 (Pt _0.3 V ₄ W ₂ /TiO ₂ ) are evaluation data of the ammonia conversion rate, carbon monoxide conversion rate, and nitrogen oxide production amount of the catalysts, respectively.
6 and 7 are Example 1 (Pt _0.3 V ₃ W ₂ /TiO ₂ ), Example 4 (Pt _0.3 V ₃ W ₁ /TiO ₂ ), Comparative Example 5 (Pt _0.3 V ₃ /TiO ₂ ), Comparative Examples 6 (Pt _0.3 V ₃ W _0.5 /TiO ₂ ) and Comparative Example 7 (Pt _0.3 V ₃ W ₃ /TiO ₂ ) are evaluation data of the ammonia conversion rate, carbon monoxide conversion rate, and nitrogen oxide production amount of the catalysts respectively prepared.

Hereinafter, a catalyst for ammonia oxidation and a method for preparing the same according to the present invention will be described in detail. The drawings introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Accordingly, the present invention is not limited to the drawings presented below and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. At this time, if there is no other definition in the technical terms and scientific terms used, it has the meaning commonly understood by those of ordinary skill in the art to which this invention belongs, and the gist of the present invention in the following description and accompanying drawings Descriptions of known functions and configurations that may be unnecessarily obscure will be omitted.

SCR is a method of decomposing nitrogen oxides into nitrogen and water by injecting a reducing agent such as ammonia into the exhaust gas, mixing it with air or steam in advance, and passing this mixed gas through a catalyst layer from the top of a reactor operated at 250 to 450°C.

Theoretically, when NH ₃ :NOx = 1:1, ammonia slip does not occur in the SCR reaction, but in the case of the rear end of the SCR of an automobile, ammonia slip occurs irregularly due to a change in temperature conditions depending on the engine load. . Therefore, in order to control such ammonia slip, an ammonia oxidation catalyst (AOC) is applied and operated.

However, in the case of the noble metal-based AOC currently used, it shows a high ammonia removal efficiency, but has a disadvantage in that the nitrogen selectivity is too low. If the nitrogen selectivity of AOC is low, ammonia is oxidized and NOx is regenerated and discharged to the outside.

Therefore, after repeated research to develop a catalyst for ammonia oxidation that can simultaneously secure excellent ammonia oxidation performance and nitrogen selectivity, TiO ₂ carrier is loaded with active materials including Pt, V ₂ O ₅ and WO ₃ in an appropriate ratio. It has been found that the above object can be achieved when doing so, and thus the present invention has been completed.

Specifically, one aspect of the present invention is a catalyst characterized in that an active material including Pt, V ₂ O ₅ and WO ₃ is supported on a TiO ₂ carrier, wherein the catalyst is TiO ₂ atomic basis with respect to 100 wt% of the carrier. It relates to a catalyst for ammonia oxidation comprising 0.1 to 3% by weight of Pt, 2 to 3% by weight of V, and 1 to 2% by weight of W as a content, and more particularly, ammonia oxidation for SCR catalyst system for application to SCR catalyst system to provide a catalyst for

As such, in the catalyst for ammonia oxidation according to the present invention, an active material including Pt, V ₂ O ₅ and WO ₃ is supported on a TiO ₂ support, and 0.1 to 3 weight of Pt in an atomic basis based on 100 wt% of the TiO ₂ support %, V 2 to 3 wt % and W 1 to 2 wt %, more preferably Pt 0.2 to 0.5 wt %, V 2.5 to 3 wt % and W 1 to 2 wt %, in an atomic basis relative to 100 wt % of the TiO ₂ carrier %, it is possible to secure excellent ammonia oxidation performance and nitrogen selectivity.

On the other hand, on an atomic basis, when the content of Pt is less than 0.1 wt%, the ammonia oxidation performance may be remarkably reduced at a low temperature of 350 °C or less, and when the content of Pt is more than 3 wt%, ammonia oxidation performance at a low temperature Silver is remarkably high, but nitrogen selectivity may be lowered. Therefore, Pt is preferably supported in an amount of 0.1 to 3% by weight, more preferably 0.2 to 0.3% by weight.

In addition, as an atomic-based content, when the content of V is less than 2% by weight, ammonia oxidation performance is significantly increased, but the nitrogen selectivity is greatly reduced, and when the content of V is more than 3% by weight, ammonia at a low temperature of 350 ° C. or less The conversion rate and carbon monoxide conversion rate may be lowered, and nitrogen selectivity in a temperature range of 330 to 380°C may be poor.

In addition, as an atomic-based content, when the content of W is less than 1 wt% or more than 2 wt%, the nitrogen selectivity may not be good.

As a specific example, the catalyst for ammonia oxidation according to the present invention may have an ammonia conversion rate of 80% or more and a nitrogen selectivity of 80% or more in a temperature range of 330 to 380°C, and an ammonia conversion rate of 95% or more at 350°C and The nitrogen selectivity may be greater than or equal to 90%.

In particular, Pt _0.3 V ₃ W ₂ /TiO ₂ or Pt _0.3 V comprising 0.2 to 0.5% by weight of Pt, 2.5 to 3% by weight of V, and 1 to 2% by weight of W, based on 100% by weight of TiO ₂ carrier In the case of ₃ W ₁ /TiO ₂ catalyst, the ammonia conversion rate may be 90% or more and the nitrogen selectivity may be 80% or more in the temperature region of 330 to 380 ° C., the ammonia conversion rate at 350 ° C. may be 95% or more and the nitrogen selectivity 95 % or more, and the carbon monoxide conversion rate at 350°C may be 90% or more, so that not only ammonia but also carbon monoxide removal effect is very excellent, it can be used as a catalyst for ammonia and carbon monoxide removal.

In addition, another aspect of the present invention relates to a method for preparing the above-described catalyst for oxidation of ammonia, specifically a) TiO ₂ Co-impregnating an active material precursor including a platinum precursor, a vanadium precursor and a tungsten precursor on a carrier (co- preparing a catalyst precursor by supporting it in an impregnation) method; and b) drying and calcining the catalyst precursor to prepare a catalyst, wherein the catalyst contains 0.1 to 3 wt% of Pt, ₂ to 3 wt% of V, and W may include 1 to 2% by weight.

First, a) TiO ₂ A catalyst precursor may be prepared by supporting an active material precursor including a platinum precursor, a vanadium precursor, and a tungsten precursor on a support in a co-impregnation method.

At this time, the content on an atomic basis based on 100 wt% of the TiO ₂ carrier is 0.1 to 3 wt% of Pt, 2 to 3 wt% of V, and 1 to 2 wt% of W, more preferably on an atomic basis based on 100 wt% of the TiO ₂ carrier. After weighing the addition amount of each precursor so as to be 0.2 to 0.5 wt% of Pt, 2.5 to 3 wt% of V, and 1 to 2 wt% of W as a content, an active material precursor aqueous solution is prepared by mixing with distilled water, and then added to the active material precursor aqueous solution A catalyst precursor may be prepared by mixing the TiO ₂ carrier and stirring it in a slurry state.

In an example of the present invention, the platinum precursor, vanadium precursor and tungsten precursor may be used without particular limitation as long as they are commonly used in the art, and specifically, for example, as a platinum precursor, tetraaminepalladium dinitrate [Pt] (NH ₃ ) ₄ ](NO ₃ ) ₂ ) and the like may be used, and ammonium metavanadate (NH ₄ VO ₃ ) may be used as a vanadium precursor, and ammonium paratungstate ((NH ₄ ) ₁₀ as a tungsten precursor. H ₂ (W ₂ O ₇ ) ₆ ) and the like may be used, but the present invention is not limited thereto.

In addition, the distilled water is sufficient enough to dissolve the active material precursor, and when the amount of distilled water is too large, it is difficult to fully support the active material precursor on the TiO ₂ carrier, and it takes a lot of time to remove moisture during drying. . In addition, if too little amount of distilled water is used, perfect mixing may not be achieved during stirring in a slurry state. Therefore, it is preferable to use an appropriate amount of distilled water.

In addition, heat may be applied with stirring in order to evaporate the distilled water more quickly. As a specific example, heat may be applied to the slurry in a hot water method. That is, the water outside the reactor can be heated by using the electric heater, and the heated water becomes a heat conduction medium to heat the slurry inside the reactor. The temperature of the water outside the reactor can be maintained at a constant temperature through the interlocking of the thermocouple and the electric heater. Specifically, for example, the temperature of the outside water is preferably maintained at 70 to 90°C.

Next, b) drying and calcining the catalyst precursor may be performed to prepare a catalyst.

The drying is to remove residual moisture, and it is preferable to dry it for more than one day using a dryer. Specifically, the drying may be performed in an electric heater capable of maintaining a constant temperature, such as furnace equipment, in an air atmosphere. In addition, the drying is preferably carried out at a temperature at which residual moisture can be sufficiently removed, for example, it is preferably carried out at 100 to 120 ℃.

Thereafter, the sintering may be performed under an air atmosphere with respect to the catalyst precursor on which the drying process has been completed. Firing may also be performed in an electric heater capable of maintaining a constant temperature, such as furnace equipment. Specifically, for example, the sintering may be performed in an air atmosphere at a temperature of 300 to 550° C. for 0.5 to 6 hours, preferably 2 to 6 hours. can be performed while In addition, the heating rate while reaching the calcination temperature may affect the catalyst properties depending on the rate, so an appropriate rate is required, and it is preferable to raise the temperature at a rate of 1 to 10°C/min.

In addition, another aspect of the present invention relates to an SCR catalyst system utilizing the above-described catalyst for oxidation of ammonia, specifically, the SCR catalyst; and a catalyst for oxidation of ammonia coated on a predetermined region of one end of the SCR catalyst.

At this time, the SCR catalyst is not particularly limited as long as it is used in the SCR catalyst system, and specifically, it may be, for example, a honeycomb structure or a plate structure, but is not limited thereto.

Hereinafter, a catalyst for ammonia oxidation and a method for preparing the same according to the present invention will be described in more detail through Examples. However, the following examples are only a reference for describing the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

Also, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of effectively describing particular embodiments only and is not intended to limit the invention. In addition, the unit of additives not specifically described in the specification may be weight %.

[Example 1]

Platinum precursor ([Pt(NH ₃ ) ₄ ](NO ₃ ) ₂ ), vanadium precursor (NH ₄ VO ₃ ) on TiO ₂ carrier (Commercial TiO ₂ , NANO, anatase) through co-impregnation method And a tungsten precursor ((NH ₄ ) ₁₀ H ₂ (W ₂ O ₇ ) ₆ ) was supported. At this time, the content of platinum atoms, vanadium atoms and tungsten atoms in the catalyst finally obtained after calcination is 0.3% by weight of Pt, 3% by weight of V, and 2% by weight of W based on 100% by weight of the TiO ₂ carrier, respectively, on an atomic basis. Each precursor was supported.

Thereafter, the catalyst for ammonia oxidation was prepared by drying at 120° C. for 6 hours and then calcining at 550° C. for 6 hours in an air atmosphere.

[Examples 2 to 4, Comparative Examples 1 to 7]

All processes were carried out in the same manner as in Preparation Example 1 except that the contents of platinum atoms, vanadium atoms and tungsten atoms in the catalyst were changed as described in Table 1 below.

(weight%) TiO ₂ carrier Pt V W Example 1 Pt _0.3 V ₃ W ₂ /TiO ₂ 100 0.3 3 2 Example 2 Pt ₃ V ₃ W ₂ /TiO ₂ 3 Comparative Example 1 Pt _0.03 V ₃ W ₂ /TiO ₂ 0.03 Example 3 Pt _0.3 V ₂ W ₂ /TiO ₂ 100 0.3 2 2 Comparative Example 2 Pt _0.3 W ₂ /TiO ₂ 0 Comparative Example 3 Pt _0.3 V ₁ W ₂ /TiO ₂ One Comparative Example 4 Pt _0.3 V ₄ W ₂ /TiO ₂ 4 Example 4 Pt _0.3 V ₃ W ₁ /TiO ₂ 100 0.3 3 One Comparative Example 5 Pt _0.3 V ₃ /TiO ₂ 0 Comparative Example 6 Pt _0.3 V ₃ W _0.5 /TiO ₂ 0.5 Comparative Example 7 Pt _0.3 V ₃ W ₃ /TiO ₂ 3

[Characteristic evaluation method]

The catalyst in powder form prepared above was molded into pellets of 30-40 mesh (425 to 600 μm), and the properties of the catalyst were evaluated according to the following conditions.

1) Pretreatment: atmospheric atmosphere of 5% by volume O ₂ , 5% by volume H ₂ O and the balance N ₂ , 1 hour, 500° C.

2) Reaction conditions: 200 ppm NH ₃ , 500 ppm CO, 5 vol % O ₂ , 5 vol % H ₂ O and residual amount of N ₂ flue gas, total flow 500 sccm, gas flow rate (SV) 100,000 h ^-1 , temperature 200~500℃

1 and 3 to 7 show the results of characteristic evaluation of the catalyst for ammonia oxidation prepared in Examples and Comparative Examples according to the above conditions.

First, Figure 1 shows the performance of Pt _0.3 V ₃ W ₂ /TiO ₂ prepared according to Example 1, the ammonia oxidation performance gradually increases as the temperature increases, so that the NH ₃ conversion rate of 90% or more at 330 to 380 ° C. and It showed N ₂ selectivity of 80% or more, and the CO conversion rate was also excellent at 80% or more.

On the other hand, in the case of a catalyst (Pt _0.3 /SCR) supporting Pt directly on a commercial catalyst, as shown in FIG. 2 , the NH ₃ conversion rate and the CO conversion rate were very excellent, but the N ₂ selectivity was remarkably lowered and the regeneration of nitrogen oxides It was found that this was actively happening.

On the other hand, FIG. 3 is data for evaluating catalytic activity characteristics according to the amount of Pt supported, and when the amount of Pt supported increased, higher oxidation performance was shown at a low temperature, but at the same time, the N ₂ selectivity also shifted to a high temperature section. was able to confirm that

Figure 4 is a data evaluation of the catalytic activity characteristics according to the amount of V ₂ O ₅ (indicated by V atom-based content), when the amount of V ₂ O ₅ supported, NH ₃ and CO oxidation performance decreases, but N ₂ selection It was confirmed that the degree increased, and it was found that the N ₂ selectivity was significantly different depending on the loading amount of V ₂ O ₅ . On the other hand, as shown in FIG. 5 , it was confirmed that the nitrogen selectivity was lowered again when V was supported in an amount of more than 3 wt %.

6 is data for evaluating the catalytic activity characteristics according to the loading amount of WO ₃ (indicated content based on W atoms), and showed almost similar oxidation performance and N ₂ selectivity, except for W 0.5 wt% (Comparative Example 6), It was confirmed that the CO conversion rate was slightly lowered when W was not supported. In addition, it was confirmed that when W was supported in an amount of more than 2 wt %, the nitrogen selectivity was lowered again.

From these results, in order to achieve high nitrogen selectivity while ensuring excellent ammonia conversion and carbon monoxide conversion, 0.1 to 3 wt% of Pt, ₂ to 3 wt% of V, and 1 to W 1 to It has been confirmed that it is important to satisfy 2 wt%, particularly preferably 0.2 to 0.5 wt% of Pt, 2.5 to 3 wt% of V, and 1 to 2 wt% of W on an atomic basis.

On the other hand, NH ₃ conversion rate, CO conversion rate, N ₂ selectivity and nitrogen oxide (NOx = NO+N ₂ O+NO ₂ ) production amount at 350° C. among the above results are briefly shown in Table 2 below.

at 350℃ NH ₃ Conversion (%) CO conversion (%) N ₂ selectivity NOx production (ppm) Example 1 Pt _0.3 V ₃ W ₂ /TiO ₂ 99.4 92.2 97.5 13.3 Example 2 Pt ₃ V ₃ W ₂ /TiO ₂ 100 100 69.4 47.7 Comparative Example 1 Pt _0.03 V ₃ W ₂ /TiO ₂ 24.7 11.1 95.1 2.4 Example 3 Pt _0.3 V ₂ W ₂ /TiO ₂ 99.2 100 64.6 64.6 Comparative Example 2 Pt _0.3 W ₂ /TiO ₂ 99.3 100 0 198.6 Comparative Example 3 Pt _0.3 V ₁ W ₂ /TiO ₂ 100 100 2.0 189.7 Comparative Example 4 Pt _0.3 V ₄ W ₂ /TiO ₂ 100 83.9 62.7 74.6 Example 4 Pt _0.3 V ₃ W ₁ /TiO ₂ 98.7 100 97.9 4.1 Comparative Example 5 Pt _0.3 V ₃ /TiO ₂ 97.0 80.8 93.6 6.2 Comparative Example 6 Pt _0.3 V ₃ W _0.5 /TiO ₂ 100 100 51.4 78.6 Comparative Example 7 Pt _0.3 V ₃ W ₃ /TiO ₂ 100 100 86.8 14.6

As can be seen from Table 2, the catalyst satisfying the composition of Pt _0.3 V ₃ W ₂ /TiO ₂ or Pt _0.3 V ₃ W ₁ /TiO ₂ is particularly excellent in NH ₃ conversion rate, CO conversion rate and N ₂ selectivity. could check

Although the present invention has been described through the specific matters and limited examples as described above, these are only provided to help a more general understanding of the present invention, and the present invention is not limited to the above examples, and the present invention pertains to Various modifications and variations are possible from these descriptions by those of ordinary skill in the art.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and not only the claims to be described later, but also all those with equivalent or equivalent modifications to the claims will be said to belong to the scope of the spirit of the present invention. .

Claims (7)

A catalyst characterized in that an active material including Pt, V ₂ O ₅ and WO ₃ is supported on a TiO ₂ carrier,
The catalyst is TiO ₂ A catalyst for ammonia oxidation, comprising 0.1 to 3% by weight of Pt, 2 to 3% by weight of V, and 1 to 2% by weight of W based on atomic content based on 100% by weight of the TiO 2 carrier.
The method of claim 1,
The catalyst for ammonia oxidation is 0.2 to 0.5 wt% of Pt, 2.5 to 3 wt% of V, and 1 to 2 wt% of W, based on 100 wt% of the TiO ₂ carrier, in an atomic basis, the catalyst for ammonia oxidation.
The method of claim 1,
The catalyst for ammonia oxidation has an ammonia conversion rate of 80% or more and a nitrogen selectivity of 80% or more in a temperature range of 330 to 380° C., A catalyst for ammonia oxidation.
The method of claim 1,
The catalyst for ammonia oxidation has an ammonia conversion rate of 95% or more and a nitrogen selectivity of 90% or more at 350° C., the catalyst for ammonia oxidation.
The method of claim 1,
The catalyst for oxidation of ammonia has a carbon monoxide conversion of 80% or more in a temperature range of 330 to 380° C., the catalyst for ammonia oxidation.
a) preparing a catalyst precursor by supporting an active material precursor including a platinum precursor, a vanadium precursor, and a tungsten precursor on a TiO ₂ carrier in a co-impregnation method; and b) drying and calcining the catalyst precursor to prepare a catalyst;
includes,
The catalyst is TiO ₂ A method for producing a catalyst for ammonia oxidation, comprising 0.1 to 3% by weight of Pt, 2 to 3% by weight of V, and 1 to 2% by weight of W based on atomic content based on 100% by weight of the TiO 2 carrier.
SCR catalyst; and the catalyst for ammonia oxidation of any one of claims 1 to 5, which is coated on a predetermined region of one end of the SCR catalyst.

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