KR102161131B1 - Antimony / titania carrier and its production method, catalyst for removal of harmful gaseous substances using the carrier, and production method thereof - Google Patents

Abstract

The present invention relates to an antimony/titania carrier and a method for producing the same, a catalyst for removing gaseous harmful substances using the carrier, and a method for producing the same. The carrier includes 0.3 to 5 parts by weight of antimony (Sb) based on 100 parts by weight of titania (TiO ₂ ), and has a bonding structure of Sb _x TiO _y . According to the present invention, when an antimony/titania carrier is first prepared under certain conditions and a reduction catalyst or an acid source catalyst is prepared by supporting an active metal on the antimony/titania carrier, the SbxTiOy bond structure is induced in the antimony/titania carrier, resulting in reducing properties and the electrophilic becomes excellent, and thus form a further denitration VxSbyO structure ₄ in the manufacture catalysts for the reduction of the vanadium as main active metals by a non-stoichiometric species, V ³⁺ and V ⁴⁺ species, in the case of Sb in the form of Sb ^{5 +} By inducing formation, oxygen transfer ability and oxygen storage ability to easily move and transfer oxygen in the gaseous phase to the catalyst grid are improved, low temperature reduction efficiency is improved, and thermal stability can be secured by suppressing the aggregation phenomenon of vanadium. In addition, when producing an oxidation catalyst using platinum as a major active metal, the oxygen mobility and oxygen storage capacity of the catalyst may be improved, thereby improving the oxidation capacity.

Description

Antimony/titania carrier and its manufacturing method, catalyst for removing gaseous harmful substances using the carrier, and its manufacturing method {ANTIMONY / TITANIA CARRIER AND ITS PRODUCTION METHOD, CATALYST FOR REMOVAL OF HARMFUL GASEOUS SUBSTANCES USING THE CARRIER, AND PRODUCTION METHOD THEREOF}

The present invention relates to a catalyst for removing harmful gaseous substances discharged from various sources, a method for manufacturing the same, a carrier used in manufacturing such a catalyst, and a method for manufacturing the same. In this case, the catalyst includes an oxidation catalyst and a reduction catalyst.

The emission of gaseous hazardous substances is increasing with recent industrial and living environment changes. Among gaseous hazardous substances, nitrogen oxides such as NO, NO ₂ , N ₂ O, NH ₃ are emitted from various emission sources such as automobiles and ships as mobile pollution sources, incinerators as fixed pollution sources, power plants and industrial boilers, and carbon monoxide as another gaseous hazardous substance. Or, organic compounds such as VOC are discharged to the atmosphere in various chemical processes. Since these gaseous hazardous substances adversely affect the environment such as global warming, obstruction of visible distance, fine dust, and acid rain, and are harmful to the human body, various methods are known to remove them. Among them, the method of removing using a catalyst is economical and It is widely applied because it is excellent in terms of technical stability.

First, in the case of nitrogen oxides among gaseous harmful substances, selective catalytic reduction (SCR) is the most widely used as a technology to remove nitrogen oxides using a catalyst. SCR is classified into ammonia-based SCR (ammonia water, ammonia, urea) and non-ammonia-based SCR (H ₂ , CO, HC) depending on the type of reducing agent, and reducing agents are used according to the characteristics of each process. Specifically, in the SCR, a reducing agent is injected into the exhaust gas at the front end of the reactor, mixed in the form of air or steam, and then the mixed gas is passed through the catalyst layer from the top of the reactor at an operating temperature, so that the reducing agent reacts selectively with nitrogen oxides to the human body and environment. It is a method of decomposing into water and ginso, which is harmless. The distinguishing feature of this SCR technology from other catalytic decomposition processes is that it uses a reducing agent and selectively reacts with nitrogen oxides. Among the reducing agents, the reducing agent most widely applied to SCR is NH ₃ and is widely applied because it has high reactivity with NOx, and in this case, the SCR reaction reacts according to the following Scheme 1. Due to such high reactivity and selectivity, it is most often used as the best available control technology (BACT). In addition, among the SCR reaction mechanisms, one of the reactions to have excellent activity at low temperature and high space velocity is the rapid reoxidation mechanism of O ₂ , which reacts as shown in Scheme 2. It is reported that the reaction rate proceeds faster than in Scheme 1, and the better the mobility of oxygen, the faster the SCR reaction proceeds.

Scheme 1

4NO + 4NH ₃ + O ₂ → 4N ₂ + 6H ₂ O

Scheme 2

2V ⁴⁺ -OH ⁺ → H ₂ O + V ³⁺ + V ⁵⁺ = O

O ₂ + 2V ³⁺ → 2V ⁵⁺ = O

The above reaction proceeds on an SCR catalyst for denitrification, and vanadium/titania (V ₂ ) using titania dioxide as a support and vanadium (V) as an active metal as a generally commercialized SCR catalyst up to now. O ₅ /TiO ₂ ) catalyst, and recently, a metal serving as a co-catalyst is added to the vanadium/titania catalyst to improve the activity and durability of the catalyst. However, in the case of such a catalyst, in order to exhibit excellent activity, a large space required for catalyst installation and a temperature of 300 ^o C or higher, which is a temperature for optimal activity, are artificially raised, but since there is a problem that causes a lot of energy loss, it is below 300 ^o C There is a need for a catalyst that can exhibit high activity at low temperatures. In addition, there is a need for a catalyst having thermal stability against deterioration of the catalyst occurring at 350 to 400 ^o C, or temporarily over 400 ^o C, in the case of gas discharged at a relatively high temperature. In addition, the activity of the catalyst gradually decreases according to the poisoning phenomenon on the catalyst surface by trace metal and SO ₂ generated during combustion, and thus durability is also required. Therefore, in order to exhibit an economic effect, it is necessary to develop a catalyst having excellent activity and excellent durability at a high space velocity.

An example of a conventional catalyst for selectively removing nitrogen oxides and a method of manufacturing the same is disclosed in Korean Patent Registration No. 10-0671978 and Non-Patent Document 1 (Applied Catalysis B Environmental, 78, pp. 301-309, 2008). . According to these prior art groups, various metals (M) and vanadium (V) such as Se, Sb, Cu, S, B, Bi, Pb and P are supported on a carrier in the form of MO _x -V ₂ O ₅ /TiO ₂ Thus, a catalyst was prepared, and antimony (Sb) was selected among them, and it is disclosed that the optimum denitration efficiency at a low temperature is displayed. In addition, since the adsorption amount of SO ₂ is small, it is disclosed that the formation of ABS (Ammonium bi sulfate; NH ₄ HSO ₄ ) salt produced by acting as a catalyst poison in a low temperature state containing SO ₂ is suppressed, and thus it can be used at a low temperature. However, these prior art groups do not disclose structural characteristics that appear by first binding antimony (Sb) to titania in the vanadium-based catalyst according to the present invention to be described later, and the effect of the combination of vanadium and antimony on the denitration efficiency.

In addition, other examples of catalysts for selectively removing nitrogen oxides are disclosed in Korean Patent No. 10-1284214 and Non-Patent Document 2 (Applied Catalysis B Environmental, 142, pp. 705-717, 2013). According to these conventional techniques, a study was conducted on the durability and activity enhancement of sulfur by adding cerium (Ce) to the Sb-V ₂ O ₅ /TiO ₂ catalyst by content. In this case, according to Non-Patent Document 2, the catalyst was prepared by first supporting cerium (Ce) in titania (TiO ₂ ) and then simultaneously supporting vanadium (V) and antimony (Sb), and cerium (Ce) is appropriate It has been reported that the addition of cerium (Ce) increases the acid point, increases the adsorption amount, and increases the oxygen mobility. However, even in these prior art groups, the role of antimony (Sb) according to the present invention, which will be described later, only discloses a portion of suppression of adsorption of SO _{2, and} the effect of antimony (Sb) on the activity in a vanadium/titania-based catalyst Not disclosed.

In addition, another example of a conventional method for selectively controlling nitrogen oxides is disclosed in Non-Patent Document 3 (Catalysis Communications, 93, pp. 33-36, 2017). According to Non-Patent Document 3, the effect of SO _{2 was} evaluated on the V ₂ O ₅ -Sb ₂ O ₃ /TiO ₂ and V ₂ O ₅ -WO ₃ /TiO ₂ catalysts. In this document, the V ₂ O ₅ -Sb ₂ O ₃ /TiO ₂ catalyst was prepared by simultaneously supporting vanadium (V) and antimony (Sb) in titania (TiO ₂ ). As a result, antimony (Sb) the catalyst is the SO ₂ absorption is suppressed, ABS by inhibiting the oxidation to SO ₃ in SO _2; is created _{(Ammonium bi sulfate NH 4 HSO 4} ) the salt is suppressed and resistance to SO ₂ Is reported to be enhanced. However, even in the case of Non-Patent Document 3, the structural characteristics of the antimony (Sb) according to the present invention to be described later on the catalyst and the resulting denitrification effect are not disclosed.

In addition, among an example of a method for selectively controlling nitrogen oxide in the related art, the most recent document is disclosed in Non-Patent Document 4 (Applied Catalysis A General, 549, pp. 310-319, 2018). According to this, the final catalyst was prepared by additionally supporting antimony (Sb) and niobium (Nb) on the VW/Ti catalyst, and the effect of ABS was studied to evaluate the SO ₂ durability of the catalyst. Among them, it was confirmed that the adsorption of SO ₂ on the catalyst was reduced through XPS, IR pattern and TG analysis for the V/W/Ti catalyst to which antimony (Sb) was added, and it was reported that durability for SO ₂ was improved through this. . However, in this Non-Patent Document 4, the structural characteristics of the addition of antimony (Sb) according to the present invention to be described later on the V/W/TiO ₂ catalyst, or the role of antimony (Sb) on the catalyst, are not mentioned. . In addition, in the case of Non-Patent Document 4, there is no particular limitation or reference to the method of adding the catalyst and the method of preparing the catalyst when preparing a catalyst using antimony.

In addition, another example of a conventional manufacturing method for selectively controlling nitrogen oxides is disclosed in Korean Patent Application Laid-Open No. 10-2017-0126837. According to this, tungsten was used as a cocatalyst in V ₂ O ₅ /TiO ₂ , and Ti-PILC and titania were mixed as a support to prepare it. In addition, in the case of tungsten, the total weight of the catalyst was 0.01 to 15% by weight, and in the case of the preparation example, 3% by weight was supported with WO ₃ . However, it is a catalyst prepared by differently preparing titania as a support from a vanadium/tungsten/titania catalyst, and as a cocatalyst, cerium (Ce), sulfur dioxide (SO ₂ ), iron (Fe), molybdenum (Mo), yttrium (Y) and Lanthans were used.

According to the prior art related to the SCR catalyst described above, there is a trend in the development of a technology for enhancing activity and durability by adding various cocatalysts to control gaseous nitrogen oxides. Among them, studies on antimony (Sb) have been conducted so far, but only the effects of suppression of adsorption of SO ₂ and poisoning on durability have been studied, and structural characteristics and antimony of the antimony/titania carrier according to the present invention described later It does not disclose the effect on the vanadium-based catalyst. On the other hand, in accordance with the recently strengthened environmental regulations, it is necessary to develop a more excellent catalyst, and ultimately, a manufacturing method that can show the optimum efficiency of a vanadium/titania-based catalyst through the properties of antimony that can improve durability and denitrification efficiency. It is a necessary situation.

Next, in the case of carbon monoxide among the gaseous hazardous substances, a method of removing using an oxidation catalyst is widely used as a technology for removing using a catalyst. In the case of an oxidation catalyst, it is a technology that converts carbon monoxide injected onto the catalyst into carbon dioxide that is harmless to the human body by reacting with oxygen in the atmosphere as shown in Scheme 3 below. These oxidation catalysts use heat as an energy source to react with carbon monoxide and oxygen to remove carbon dioxide.At this time, the reaction temperature is different depending on the performance of the catalyst, and a catalyst capable of oxidizing carbon monoxide to carbon dioxide at a low temperature is an excellent catalyst. I can.

Scheme 3

2CO + O ₂ → CO ₂

On the other hand, in the case of various chemical processes involving carbon monoxide, heat energy is artificially injected and removed to treat exhaust gas, and economic losses are incurred due to high reaction temperatures. In addition, energy facilities such as power plants have a problem of acting as a poison of the catalyst due to SO _{2 that} is inevitably generated during combustion. Therefore, the development of an oxidation catalyst capable of oxidizing carbon monoxide at a lower temperature than before and a catalyst technology having resistance to SO ₂ as a poisonous substance are required.

An example of a conventional catalyst for removing carbon monoxide and a method for manufacturing the same is disclosed in Korean Patent No. 10-0998325 and Korean Patent No. 10-1319064. Korean Patent No. 10-0998325 and Korean Patent No. 10-1319064 disclose platinum/titania catalysts and palladium/titania catalysts, respectively, as catalysts for removing carbon monoxide, and the patents are generally used titania A process of supporting platinum and palladium as active metals on a carrier is disclosed.

In addition, non-patent document 5 (Catal. Sci. Technol., 2018, 8, 782) discloses a catalyst in which antimony (Sb) is used to remove carbon monoxide. According to the non-patent document 5, the content of removing carbon monoxide using antimony, tin oxide, and platinum is disclosed. However, in the case of Non-Patent Document 5, there is a problem in that the carbon monoxide removal rate is somewhat low as tin oxide is used.

According to the prior art related to the oxidation catalyst, catalysts using various active metals including platinum are disclosed to control gaseous carbon monoxide, but structural features and antimony oxidation catalysts of the antimony/titania carrier according to the present invention described below It does not disclose the effect on the.

Korean Patent Registration No. 10-0671978 Korean Patent Registration No. 10-1284214 Republic of Korea Patent Publication No. 10-2017-0126837 Korean Patent Registration No. 10-0998325 Korean Patent Registration No. 10-1319064

Applied Catalysis B Environmental, 78, pp. 301-309, 2008 Applied Catalysis B Environmental, 142, pp. 705-717, 2013 Catalysis Communication, 93, 33-36, 2017 Applied Catalysis A General, 549, pp. 310-319, 2018 Catal. Sci. Technol., 2018, 8, 782

It is an object of the present invention to provide a catalyst having excellent low-temperature activity and thermal stability, effectively suppressing catalyst poisoning, and excellent gaseous hazardous substance removal efficiency, and a method for producing the same. In this case, the catalyst includes a reduction catalyst that reduces and removes harmful gas using vanadium or the like as an active metal, and an oxidation catalyst that oxidizes and removes harmful gas using platinum as an active metal. Another object of the present invention is to provide an antimony/titania carrier having excellent reducing properties and electrophilicity, which can be advantageously applied to the catalyst, and a method for preparing the same.

In the process of researching and developing a catalyst related to the above problem, the present inventors have found that when an antimony/titania carrier is first prepared under specific conditions, a SbxTiOy bond structure between antimony and titania is induced, and thus reducing properties and electrophilicity are excellent. . In addition, the present inventors further formed a VxSbyO ₄ structure when preparing a reduction catalyst for denitrification using vanadium as a major active metal using such an antimony/titania carrier, so that non-stoichiometric species V ³⁺ and V ⁴⁺ species, Sb, Sb ⁵ By inducing formation in the form of ⁺ , the oxygen transfer ability and oxygen storage ability to easily move and transfer oxygen in the gaseous phase to the catalytic lattice are improved, thereby improving the low-temperature reduction efficiency and also suppressing the aggregation phenomenon of vanadium for thermal stability. While discovering that this can be secured, it was found that the oxidation capacity was improved by improving the oxygen mobility and oxygen storage capacity of the catalyst when preparing an oxidation catalyst containing platinum as the main active metal using the antimony/titania support. Reached. The gist of the present invention based on the recognition and knowledge on the above-described problem is as follows.

(1) Titania (TiO ₂ ) Antimony (Sb) 0.3 to 5 parts by weight based on 100 parts by weight, antimony/tinatia carrier, characterized in that it has a bonding structure of Sb _x TiO _y .

(2), titania (TiO ₂₎ antimony, antimony, characterized in that (Sb) the step of supporting the antimony precursor on the titania (TiO ₂₎ such that an amount of 0.3 to 5 parts by weight is produced by baking at 500 ~ 650 ℃ based on 100 parts by weight of / Method for producing titania carrier.

(3) The antimony precursor is antimony chloride (SbCl ₃ ,), antimony acetate ((CH ₃ CO ₂ ) ₃ Sb), antimony nitrate (2Sb ₂ O ₃ N ₂ O ₅ ) ), antimony sol (antimony sol: Sb ₂ O ₄ ), the antimony/tinatia carrier manufacturing method of (2), characterized in that any one of.

(4) A reduction catalyst comprising 0.3 to 4 parts by weight of vanadium (V) with respect to 100 parts by weight of the antimony/titania carrier according to (1), and having a bonding structure of VxSbyO4.

(6) A reduction catalyst manufacturing method, characterized in that it is prepared by sintering at 400 to 500°C by supporting a vanadium precursor so that 0.3 to 4 parts by weight of vanadium (V) per 100 parts by weight of the antimony/titania carrier according to (1) above. .

(7) The method for producing the reduction catalyst of (6), wherein the vanadium precursor is a soluble compound.

(10) An oxidation catalyst comprising 0.1 to 3 parts by weight of platinum (Pt) based on 100 parts by weight of the antimony/titania carrier according to (1).

(11) An oxidation catalyst manufacturing method, characterized in that it is prepared by sintering at 400 ^o C by supporting a platinum precursor so that 0.1 to 3 parts by weight of platinum (Pt) per 100 parts by weight of the antimony/titania carrier according to (1).

(12) The method for producing the oxidation catalyst of (11), wherein the platinum precursor is a soluble compound.

According to the present invention, when an antimony/titania carrier is first prepared under certain conditions and a reduction catalyst or an acid source catalyst is prepared by supporting an active metal on the antimony/titania carrier, the SbxTiOy bond structure is induced in the antimony/titania carrier, resulting in reducing properties and the electrophilic becomes excellent, and thus form a further denitration VxSbyO structure ₄ in the manufacture catalysts for the reduction of the vanadium as main active metals by a non-stoichiometric species, V ³⁺ and V ⁴⁺ species, in the case of Sb in the form of Sb ^{5 +} By inducing formation, oxygen transfer ability and oxygen storage ability to easily move and transfer oxygen in the gaseous phase to the catalyst grid are improved, low temperature reduction efficiency is improved, and thermal stability can be secured by suppressing the aggregation phenomenon of vanadium. In addition, when producing an oxidation catalyst using platinum as a major active metal, the oxygen mobility and oxygen storage capacity of the catalyst may be improved, thereby improving the oxidation capacity.

1 is a graph of XRD (X-ray diffraction) analysis results for Preparation Example 1 and Comparative Example 1 of the present invention.
2 is a graph of the results of pL spectroscopy analysis for Preparation Example 1 and Comparative Example 1 of the present invention.
3 is a graph of the results of H ₂ -TPR (H ₂ Temperature Programmed Reduction) analysis for Preparation Example 1 and Comparative Example 1 and Comparative Preparation Example 5 of the present invention.
Figure 4 (a) is a graph showing the nitrogen oxide removal rate according to the firing temperature in Preparation Example 2 of the present invention.
Figure 4 (b) is a graph of the H ₂ -TPR (H ₂ Temperature Programmed Reduction) analysis result for confirming the change in reduction characteristics according to the firing temperature in Preparation Example 2 of the present invention.
5 is a graph of XRD analysis results for Preparation Example 2 and Comparative Preparation Example 3 and Comparative Preparation Example 4 of the present invention.
6 is a graph of TPR (Temperature Programmed Reduction) analysis results for Preparation Examples 1 and 2 of the present invention and Comparative Preparation Example 3 and Comparative Preparation Example 4. FIG.
Figure 7 (a) is a graph of the analysis result of XPS (X-ray photoelectron spectroscopy) for Preparation Example 3 and Comparative Preparation Example 1 of the present invention.
7 (b) is a graph of the results of XPS (X-ray photoelectron spectroscopy) analysis for Preparation Example 3 and Comparative Preparation Example 1 of the present invention.
Figure 8 is a graph of the results of TPRO (H ₂ Temperature Programmed Reduction and Oxidation) analysis for Preparation Example 3 and Comparative Preparation Example 1 of the present invention.
9 (a) is a graph of DRFTs analysis results for Preparation Example 2 and Comparative Preparation Example 3 of the present invention.
Figure 9 (b) is a graph of the IR-DRIFTs analysis results for Preparation Example 2 and Comparative Preparation Example 3 of the present invention.
11 is a graph of Raman spectroscopy analysis results for Preparation Example 2, Comparative Preparation Example 3 and Comparative Preparation Example 4 of the present invention.
15 is a graph showing carbon monoxide conversion rates for Preparation Example 9 and Comparative Preparation Example 6 of the present invention.
16 is a graph showing the carbon monoxide conversion rate over time for Preparation Example 9 and Comparative Preparation Example 6 of the present invention.

Hereinafter, the present invention will be described in detail. The present invention basically relates to an antimony/titania carrier and a method for producing the same, and relates to a reduction catalyst and an oxidation catalyst carrying an active metal on the antimony/titania carrier, which will be sequentially described below.

The antimony/titania carrier is prepared by supporting an antimony (Sb) precursor on titania (TiO ₂ ) and firing at a predetermined temperature, and the resulting carrier has a bonding structure of Sb _x TiO _y .

When the antimony precursor is supported on the titania, it is preferable to quantify the amount of antimony (Sb) to include 0.3 to 5 parts by weight based on 100 parts by weight of titania (TiO ₂ ). If the antimony content is less than 0.3 parts by weight, it is not preferable because the amount of the bond structure of SbxTiOy is too small, and if it exceeds 5 parts by weight, it is preferable because the micropores of titania (TiO ₂ ) can be blocked by the addition of an excessive amount of antimony (Sb). Not.

Antimony (Sb) precursor material is antimony chloride (antimony chloride: SbCl ₃ ,), antimony acetate ((CH ₃ CO ₂ ) ₃ Sb), antimony nitrate (2Sb ₂ O ₃ N ₂ O ₅ )), antimony sol (Sb ₂ O ₄ ) It may be selected from any one of.

The firing temperature for preparing the antimony/titania carrier is preferably performed at 500 to 650°C. If the firing temperature is less than 500°C, it is not preferable because it cannot form the SbxTiOy structure, and if it exceeds 650°C, it is not preferable because it may cause agglomeration of the material due to high thermal energy.

The antimony/titania carrier has excellent reducibility and electrophilicity by having a bonding structure of Sb _x TiO _y , and accordingly, an antimony/titania carrier having a special bonding structure of Sb _x TiO _y is first prepared and then this carrier The physical properties of the catalyst are improved by supporting the active metal on the catalyst to prepare the desired final reduction catalyst or oxidation catalyst.

First, the reduction catalyst may be, for example, a catalyst for removing nitrogen oxides using vanadium (V) as a major active metal. Such a reduction catalyst can be prepared by supporting a vanadium precursor on a previously prepared antimony/titania carrier and firing at a predetermined temperature, and the resulting reduction catalyst is characterized in that it has a bonding structure of VxSbyO4.

When the vanadium precursor is supported on the antimony/titania carrier, it is preferable to quantify so that 0.3 to 4 parts by weight of vanadium (V) is carried out with respect to 100 parts by weight of the antimony/titania carrier. If the vanadium content is less than 0.3 parts by weight, the amount of the active metal site is too small, which is not preferable, and if it exceeds 4 parts by weight, it is not preferable because the micropores of the antimony/titania (Sb/TiO ₂ ) carrier can be blocked.

The vanadium precursor material is not particularly limited as long as it is a soluble compound including, for example, ammonium metavanadate (NH ₄ VO ₃ ). As a precursor material, the term'dissolvable compound' refers to a compound capable of being ionized and supported by being highly dispersed in a carrier as the precursor is easily dissolved in distilled water.

The firing temperature for preparing the reduction catalyst is preferably performed at 400 to 500°C. If the sintering temperature is less than 400°C, it is not preferable because the VSbO ₄ structure cannot be formed, and if it is higher than 500°C, agglomeration of the catalyst may occur due to high temperature, which is not preferable.

The mechanism of action for improving the physical properties of the reduction catalyst by the antimony/titania carrier having the binding structure of Sb _x TiO _y in the reduction catalyst is as described above, as described above, the SbxTiOy bond structure is induced in the antimony/titania carrier, resulting in reducing properties and electrophiles. becoming is excellent, thereby further form a denitration VxSbyO structure ₄ in the manufacture catalysts for the reduction of the vanadium as main active metals by a non-stoichiometric species in the case of V ³⁺ and V ⁴⁺ species, Sb generated in the form of Sb ^{5 +} By inducing gaseous oxygen to the catalyst lattice, oxygen transfer capacity and oxygen storage capacity are increased, so that the SCR reaction cycle is accelerated, so that the efficiency of removing harmful gases at low temperatures is excellent, and vanadium aggregation occurs. By suppressing the thermal stability, even when the catalyst is exposed to high temperature, it is possible to ensure thermal stability.

Next, the oxidation catalyst may be, for example, a catalyst for removing carbon monoxide using platinum (Pt) as a major active metal. Like the reduction catalyst, this oxidation catalyst can be prepared by supporting a platinum precursor on a pre-prepared antimony/titania support and calcining at a predetermined temperature, thereby improving the oxygen mobility and oxygen storage capacity of the catalyst, thereby increasing the oxidation capacity. It can be improved.

When the platinum precursor is supported on the antimony/titania carrier, it is preferable to quantify so that 0.1 to 3 parts by weight of platinum (Pt) is carried out with respect to 100 parts by weight of the antimony/titania carrier. If the vanadium content is less than 0.1 parts by weight, the amount of the active metal is too small and the activity is low, which is not preferable, and if it exceeds 3 parts by weight, it is not preferable considering the economics due to the use of an excessive amount of precious metal.

Examples of the platinum precursor material include platinum chloride (PtCl ₄ ), tetra-amine platinum nitrate (Pt(NH ₃ ) ₄ (NO ₃ ) ₂ ), and hydroxyl platinum ((NH ₂ -CH ₂ CH ₂ -OH. 2Pt(OH) ₆ ) or platinum hydroxide (Pt(OH) ₂ ) is not particularly limited as long as it is a soluble compound.

The firing temperature for preparing the oxidation catalyst is preferably performed at 400°C. If the calcination temperature is less than 400° C., the bond between platinum and the antimony/titania carrier is not sufficiently formed, which is not preferable. If the calcination temperature is higher than 400° C., agglomeration of the catalyst may be caused, which is not preferable.

The mechanism of action for improving the physical properties of the oxidation catalyst by the antimony/titania carrier having the binding structure of Sb _x TiO _y in the oxidation catalyst is, as described above, the SbxTiOy bond structure is induced in the antimony/titania carrier, resulting in reducing and electrophilic As a result, the oxygen transfer capability and oxygen storage capability that can easily move and transfer gaseous oxygen to the catalyst lattice can be improved when producing an oxidation catalyst using platinum as a major active metal.

The reduction catalyst and oxidation catalyst according to the present invention prepared as described above are provided in the form of powder, or are formed by themselves in various bulk shapes such as honeycomb, slate, or pellet, or are provided by forming a plate or fiber made of metal or ceramic. , Can be used by coating the surface of a filter or honeycomb structure.

Hereinafter, the present invention will be described in more detail based on preferred embodiments and experimental examples of the present invention. However, the technical idea of the present invention is not limited or limited thereto, and may be modified and variously implemented by those skilled in the art.

Method of measuring harmful gas removal ability by catalyst

In the following examples and experimental examples, the ability to remove harmful gases by the reduction catalyst and the oxidation catalyst according to the present invention was performed in the following manner.

Measurement of the nitrogen oxide removal ability by the reduction catalyst was performed by calculating the conversion rate of gaseous nitrogen oxide according to Equation 1 below. The concentration of NO discharged from the rear end of the catalyst layer was measured with a non-dispersive infrared gas analyzer (ZKJ-2, Fuji Electric Co.), and in the case of N ₂ O, it was measured and calculated with Ultramat6 (Siemens Co.), and ammonia. The concentration of was measured with a detection tube (3M, 3La, 3L, GASTEC Co.).

The measurement of carbon monoxide removal ability by the oxidation catalyst was performed by calculating the conversion rate of gaseous carbon monoxide according to Equation 2 below. The concentrations of CO and CO ₂ discharged from the rear end of the catalyst layer were measured and calculated with a non-dispersive infrared gas analyzer (ZKJ-2, Fuji Electric Co.).

Manufacturing example One

First, an antimony precursor selected from any one of antimony acetate ((CH ₃ CO ₂ ) ₃ Sb: a brand name of Aldrich Chemical Co.), and an antimony oxide ((Sb ₂ O ₅ : a brand name of Alfa Aesar Co.)) is titania 100% by weight. It is quantified so as to be 2 parts by weight and dissolved in distilled water at room temperature. After that, an antimony aqueous solution is added to the prepared titania and mixed to form a slurry, dried using a vacuum rotary evaporator, and then placed in fine pores. In order to completely remove the residual impurities contained, it was sufficiently dried in a dryer at 103 ^o C for more than 24 hours. After that, the temperature was raised to 300 to 800 ^o C at intervals of 100 ^o C at a heating rate of 10 ^o C/min in a square furnace. Then, it is calcined in an air atmosphere for 4 hours to prepare an antimony/titania carrier.

Manufacturing example 2

Using ammonium metavanadate (NH ₄ VO ₃ : Aldrich Chemical Co.) as a precursor of vanadium, vanadium was quantified to 2 parts by weight based on 100 parts by weight of the antimony/titania carrier prepared according to Preparation Example 1, and then added to distilled water at room temperature. Dissolve. Thereafter, an aqueous vanadium solution was added to and mixed with the prepared antimony/titania carrier, prepared in a slurry form, dried using a vacuum rotary evaporator, and then at 103 ^° C to completely remove residual impurities contained in the micropores. It was sufficiently dried for 24 hours or more in a dryer. Thereafter, the temperature was raised to a temperature of 500 ^o C at a temperature rising rate of 10 ^o C/min in a square furnace, and then fired in an air atmosphere for 4 hours to prepare a vanadium/antimony/titania reduction catalyst.

Manufacturing example 3

When the vanadium precursor in Preparation Example 2 is supported on the prepared antimony/titania carrier, antimony prepared tungsten using ammonium metatungsten (NH ₄ ) ₆ (H ₂ W ₁₂ O ₄₀ : Aldrich Chemical Co.) as a tungsten precursor is used. / A vanadium-tungsten/antimony/titania reduction catalyst was prepared in the same manner as in Preparation Example 2, except that it was quantitatively dissolved and prepared in an aqueous solution state with respect to 100 parts by weight of the titania carrier, and supported together with an aqueous vanadium solution. Was prepared.

Manufacturing example 4

A vanadium-tungsten/antimony/titania catalyst was prepared in the same manner as in Preparation Example 3, except that 3 parts by weight of tungsten was made based on 100 parts by weight of the prepared antimony/titania carrier in Preparation Example 3.

Manufacturing example 9

Platinum hydroxide (Pt(OH) ₂ ) was quantified as a platinum precursor so as to be 1 part by weight based on 100 parts by weight of the antimony/titania carrier prepared according to Preparation Example 1, and dissolved in distilled water at room temperature. After turning on the platinum aqueous solution in ready-antimony / titania carrier and then a solution prepared in the form slurry (Slurry) was dried using a vacuum rotary evaporator to completely remove the residual impurities contained in the fine pores of 103 ^o C It was sufficiently dried for 24 hours or more in a dryer. Thereafter, the temperature was raised to 400 ^o C at a temperature raising rate of 10 ^o C/min in a square furnace, and then fired in an air atmosphere for 4 hours to prepare platinum/antimony/titania.

Comparative Production Example One

In Preparation Example 3, a vanadium/titania catalyst was prepared in the same manner as in Preparation Example 3, except that the carrier was used as titania instead of antimony/titania.

Comparative Production Example 2

A vanadium-tungsten/titania catalyst was prepared in the same manner as in Comparative Preparation Example 1, except that an aqueous solution was prepared by quantifying tungsten to be 5 parts by weight based on 100 parts by weight of titania.

Comparative Production Example 3

A vanadium-antimony/titania catalyst was prepared in the same manner as in Comparative Preparation Example 1, except that an aqueous solution was prepared by quantifying antimony instead of tungsten to be 2 parts by weight based on 100 parts by weight of titania.

Comparative Production Example 4

A vanadium/titania catalyst was prepared in the same manner as in Preparation Example 2, except that the carrier was used as titania instead of antimony/titania in Preparation Example 2.

Comparative Production Example 5

The titania carrier was heated to a temperature of 500 ^o C at a temperature rising rate of 10 ^o C/min in a square furnace, and then calcined in an air atmosphere for 4 hours to prepare.

Comparative Production Example 6

A platinum/titania catalyst was prepared in the same manner as in Preparation Example 9, except that the carrier was used as titania instead of antimony/titania in Preparation Example 9.

Preparation Examples 1 to 9 and Comparative Preparation Examples 1 to 6 of the present invention are summarized in Table 1 below. In Table 1, “%” is based on weight.

division ingredient Antimony/titania
Firing temperature content Manufacturing Example 1 Antimony/titania 300 ^o C Antimony: 2% 400 ^o C Antimony: 2% 500 ^o C Antimony: 2% 600 ^o C Antimony: 2% 700 ^o C Antimony: 2% 800 ^o C Antimony: 2% Manufacturing Example 2 Vanadium/antimony/titania 300 ^o C Vanadium: 2%, antimony 2% 400 ^o C 500 ^o C 600 ^o C 700 ^o C 800 ^o C Manufacturing Example 3 Vanadium-tungsten/antimony/titania 600 ^o C Vanadium: 2%, Tungsten: 1%,
2% antimony Manufacturing Example 4 Vanadium-tungsten/antimony/titania Vanadium: 2%, Tungsten: 3%,
2% antimony Manufacturing Example 9 Platinum/antimony/titania 600 ^o C Platinum: 1%, antimony 2% Comparative Production Example 1 Vanadium-tungsten/ titania - Vanadium: 2%, Tungsten: 1% Comparative Production Example 2 Vanadium-tungsten/ titania Vanadium: 2%, Tungsten: 5% Comparative Production Example 3 Vanadium-antimony/ titania Vanadium: 2%, Antimony: 2% Comparative Production Example 4 Vanadium/titania - Vanadium: 2% Comparative Production Example 5 Titania 600 ^o C Commercial titania Comparative Production Example 6 Platinum/Titania Platinum: 1% Comparative Example 1 Titania - Commercial titania

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Experimental example One

In order to confirm the reducing properties and electrophilic properties of the antimony/titania carrier, XPS analysis was performed on the antimony/titania carrier prepared according to the firing temperature according to Preparation Example 1. In this case, by checking the structure and oxidation state formed when antimony and titania are bonded during the preparation of the antimony/titania carrier, an antimony/titania carrier having optimum reducing properties and electrophilicity can be prepared. Table 2 below shows the firing temperatures of Preparation Example 1, and shows the ratio of the trivalent species among the total oxidation values of antimony. From the results below, it can be determined that the ratio of the trivalent species of antimony increases when antimony is combined with titania and SbxTiOy, which is an unstable structure, when heat treatment at a temperature of 500 to 600 oC when preparing a carrier. For example, when combined with SbxTiOy, electron mobility and reducibility can be improved as it exists in an unstable structure.

Antimony/titania carrier Sb ^{3 +} /Total (%) Preparation Example 1-300 37.77 Preparation Example 1-400 45.76 Preparation Example 1-500 53.84 Manufacturing Example 1-600 57.56 Manufacturing Example 1-700 47.92

Experimental Example 2

XRD (X-Ray Diffraction) analysis was performed to confirm the binding of antimony and titania of the antimony/titania carrier, and the results are shown in FIG. 1 . Analysis was shown for Comparative Example 1 in the form of initial TiO _{2 and} Preparation Example 1 to which antimony was added. In Comparative Example 1, the anatase peak intensity of titania was observed to be very high. This result means that the used titania crystal has a high degree of crystallinity in the anatase structure. On the other hand, in the case of Preparation Example 1, it was found that the anatase peak intensity of titania decreased as the SbxTiOy structure mentioned above was generated as antimony was added. These results are the results observed to be lower than the anatase peak intensity of Preparation Example 1 compared to Comparative Example 1 as antimony combined with titania to generate the SbxTiOy structure and the anatase structure shape decreased.

Experimental Example 3

In order to determine how the addition of antimony and active metal to the antimony/titania carrier affects electron mobility, pL spectroscopy analysis was performed and the results are shown in FIG. 2 . Analysis was shown for Comparative Example 1 in the form of initial TiO _{2 and} Preparation Example 1 to which antimony was added. The intensity of the pL signal has a low intensity as oxygen vacancy is formed while electrons are easily transferred. As a result of the analysis, it was confirmed that when antimony was added compared to the initial titania, a very large decrease in intensity appeared. That is, when antimony is added during the preparation of the carrier, excellent electron mobility is imparted to facilitate the movement of gaseous oxygen to the lattice in the catalyst. In the case of PL spectroscopy analysis, the decrease in intensity indicates excellent electron mobility, and the excellent electron mobility means that oxygen transfer is easier.

Experimental Example 4

In order to check the reducing properties of the antimony/titania carrier, Comparative Example 1, which is commercialized titania (TiO ₂ ), and Preparation Example 1-600 in which antimony and titania were combined by heat treatment at 600 ^o C, as a comparative example, the same as the antimony supporting temperature. H ₂ -TPR (H ₂ Temperature Programmed Reduction) analysis was performed on Comparative Preparation Example 5 heat-treated at 600 ^o C. By using oxygen species inside the catalyst, the reaction of nitrogen oxides, ammonia, and oxygen to be sent to nitrogen can be carried out. By measuring the amount of hydrogen consumed by injecting hydrogen gas while raising the temperature of the catalyst, the amount of oxygen in the catalyst is measured. The quantities can be compared indirectly. That is, the hydrogen consumption area means the amount of oxygen in the catalyst. Specifically, 2920 Autochem (Micromeritics) was used, and H ₂ -TPR analysis was performed using TCD (Thermal Conductivity Detector) as a detector for measuring concentration. The order of the analysis is to fill the pulverized 0.3g catalyst to less than 100 um, and then first, heat 50 cc/min of 5 vol.% O ₂ /He to 10°C/min, and flow it at 400°C for 30 minutes to remove the impurities on the surface. Removed. After continuing to lower the temperature to room temperature, 5 vol.% H ₂ /Ar was injected for 1 hour to make the catalyst a reducing atmosphere. Then, while raising the temperature at 10° C./min, the amount of hydrogen consumption was measured to 700 ^° C.

Looking at the results shown in FIG. 3, in the case of Comparative Example 1, the hydrogen reduction peak was observed at 500 to 600 ^o C, and in Comparative Preparation Example 5 subjected to heat treatment, not only the oxygen species in the catalyst decreased, but also the reduction peak moved to a high temperature. I could confirm. However, in the case of Preparation Example 1-600 in which antimony was supported, it was confirmed that not only the oxygen species in the catalyst increased, but also the reduction peak was shifted to a low temperature, which was confirmed that the reduction property was improved, which makes it easier to consume hydrogen of the catalyst. .

Experimental Example 5

When preparing a vanadium/antimony/titania catalyst, an effect of improving the oxygen storage capacity and reducing property of the carrier may be obtained through the combination of antimony/titania before the vanadium is supported. Therefore, in order to check the optimum binding conditions of antimony/titania in the temperature range of 300 ^o C or less, the calcination temperature of antimony/titania was prepared in a 100 ^o C gradient from 300 ^o C to 800 ^o C, and then vanadium was prepared. The nitrogen oxide removal rate of the supported catalyst was measured and shown in Fig. 4(a) . The catalyst was prepared as in Preparation Example 2, but the calcination temperature of antimony/titania was added to the rear end and indicated as Preparation Example 2- (calcination temperature), and the catalyst name was indicated with the number after the Example as the calcination temperature. Concentration of 800 ppm, NOx / ammonia in this case, nitrogen oxide is 1: was a 1 and an oxygen content of 10%, water 6 vol%, a space velocity is 180,000 h ^- was determined by keeping a ^1. Among them, as a result of comparing the denitrification efficiency based on 250 ^o C, which shows a large difference in activity, the catalyst prepared in Preparation Example 2-600 showed the best denitrification efficiency, and the catalyst prepared in Preparation Example 2-600 was 84.57%. It showed the best activity at 250 ^o C. To confirm this activity enhancement caused is shown in FIG. 4 (b) to perform a H ₂ -TPR analyzed to determine the redox properties of the catalyst. It was confirmed that the higher the heat treatment temperature of antimony/titania, the more the reduction peak of hydrogen moved to the lower temperature. As the heat treatment temperature increased, it was confirmed that the reduction property increased as the antimony/titania bond became stronger. However, at a temperature of 600 ^o C or higher, the specific surface area is rather reduced by heat treatment at a high temperature as shown in Table 3 below, thereby reducing the nitrogen oxide removal rate. For reference, the calculation results of the nitrogen oxide removal rate are shown in Table 4 below.

division Temperature (℃): 250 Specific surface science Preparation Example 2-300 89.066 Preparation Example 2-400 88.467 Preparation Example 2-500 82.246 Preparation Example 2-600 73.407 Preparation Example 2-700 37.858

division Temperature (℃): 250 Nitrogen oxide removal rate (%) Preparation Example 2-300 57.125 Preparation Example 2-400 63.125 Preparation Example 2-500 71.5 Preparation Example 2-600 84.57 Preparation Example 2-700 74.375 Production Example 2-800 59.875

Experimental example 6

In order to confirm the structural features of vanadium/antimony/titania, an XRD analysis that can generally confirm the structure was performed, and the results are shown in FIG. 5 . In order to reliably observe the structural change, the contents of vanadium and antimony in Preparation Example 2, Comparative Preparation Example 3, and Comparative Preparation Example 4 were prepared so that the content of titania was 100 parts by weight of 10, followed by analysis. As a result, in the case of the catalyst in Comparative Preparation Example 4, it was confirmed that the peak of V ₂ O ₅ was largely observed by vanadium supported in an excessive amount. However, in the case of Preparation Example 2 and Comparative Preparation Example 3 to which antimony was added, it was confirmed that all of the V ₂ O ₅ peaks disappeared and a new rutile peak of VxSbyO ₄ types was generated. Among them, in the case of Preparation Example 2, it was confirmed that the structure of VxSbyO ₄ was further developed. In the resulting structure, vanadium disilver exists as V ³⁺ and V ⁴⁺ species, which are unstable oxidation states. The oxidation state of vanadium, which is unstable in the SCR reaction, enhances electron mobility, thereby enhancing the oxygen transfer ability that makes it easier to move oxygen in the lattice and gas phase in the catalyst. Excellent oxygen transfer power and electron mobility can have excellent denitrification efficiency.

Experimental example 7

H ₂ -TPR analysis was performed on Preparation Example 1 and Preparation Example 2, Comparative Preparation Example 3, and Comparative Preparation Example 4 in order to confirm the reduction characteristics of the catalyst according to the preparation method after vanadium was supported, and the results are shown in FIG . Indicated. In the case of the experimental method, it was carried out in the same manner as in Experimental Example 4. As a result, in the case of Comparative Production Example 4 in which vanadium was supported on commercialized titania, a reduction peak of vanadium was observed around 400 ^o C. In the case of Comparative Preparation Example 3, it was confirmed that the maximum reduction temperature of vanadium was not significantly changed as a catalyst in which vanadium and antimony were supported together, and a reduction peak of thymon was observed near 430 ^o C. However, in the case of Preparation Example 1 using antimony/titania as a carrier, it was confirmed that the reduction peaks of vanadium and antimony started from a lower temperature. Through this, it was confirmed that in the case of a catalyst prepared using an antimony/titania carrier, oxygen species in the catalyst can be used more easily.This affects the oxidation state of vanadium by antimony/titania, and thus the electron mobility of the catalyst. It was confirmed that it can further improve. This enhancement of electron mobility can improve the denitration efficiency by speeding up the reaction progress in the catalytic reaction.

Experimental example 8

In order to determine the oxidation state of the carrier presence of the antimony / titania-vanadium-based catalyst of vanadium-be subjected to the tungsten oxide / antimony / titania in Production Example 3, and vanadium / tungsten oxide / titania catalyst of comparative XPS analysis for Preparation 17 Shown in. In order to confirm the oxygen transport characteristics of the catalyst according to the addition of antimony, the oxygen species were separated by measuring V 2p and O 1s for the two catalysts, respectively, and are shown in FIGS. 7(a) and 7(b) , respectively . Done. As a result, O 1s oxygen species are largely divided into lattice oxygen species (Oβ) and surface chemical adsorption oxygen species (Oα).In general, the ratio of surface adsorption oxygen species (Oα), which is known to have excellent oxygen mobility, is greatly increased. I could confirm that. As shown in (b) of FIG. 7 showing the oxidation state of vanadium, in the case of the catalyst to which antimony was added, in the case of V 2p, the ratio of the trivalent and tetravalent species in which the oxidation state of vanadium was unstable was present at a higher ratio. . In addition, through the oxidation state of vanadium, that is, when vanadium and cocatalyst were added after antimony/titania was combined, the oxidation state of vanadium became unstable, and electron mobility was significantly increased. It is shown for each ratio in Table 5 below. As a result, in the case of Preparation Example 3 using antimony/titania as a carrier, the ratio of trivalent and tetravalent species, which are non-stoichiometric species of vanadium, was 58.8%, and in Comparative Preparation Example 1, which did not use antimony/titania as a carrier, it was 46.13%. It was confirmed that relatively small proportion of electrons in an unstable state of vanadium existed. As shown in relation to the oxidation state of antimony mentioned in Experimental Example 1, the more antimony in the antimony/titania phase exists as trivalent species, the better the denitrification efficiency, which is a stable form formed during initial catalyst production when vanadium is supported. It was confirmed that phosphorus vanadium pentavalent was reduced to further form vanadium trivalent and tetravalent species, which are non-stoichiometric species. Accordingly, it was confirmed that the antimony/titania carrier induces electrophilicity by affecting the oxidation state of vanadium and thus has a better denitrification efficiency.

V ³⁺ +V ⁴⁺ /Vtotal ratio Oα/( Oα+ Oβ) ratio Manufacturing Example 3 58.80 24.45 Comparative Production Example 1 46.13 18.29

Experimental Example 9

TPRO (Temperature Programmed Reduction and Oxidation) analysis was performed on the catalysts of Preparation Example 3 and Comparative Preparation Example 1 in order to confirm the reoxidation characteristics of oxygen according to the enhancement of electron mobility of the vanadium/antimony/titania catalyst, and FIG . The analysis results are shown. This analysis technique is an analysis technique for confirming the use capacity of oxygen by injecting oxygen from room temperature again on the reduced catalyst after the TPR analysis performed in Experimental Example 2. As a result of the analysis, in the case of Preparation Example 3 using antimony/titania as a carrier, it was confirmed that reoxidation began at around 164 ^o C, and in Comparative Preparation Example 1, reoxidation started at around 188 ^o C. As in Experimental Example 7, the mobility of oxygen increased due to the increase in electron mobility, and thus oxygen could be used at a lower temperature.The characteristics of the catalyst capable of using oxygen well were nitrogen oxides and ammonia in the SCR reaction mechanism. And by enhancing the reactivity of oxygen, it is possible to more easily send it to N ₂ , so that the nitrogen oxide removal rate can be increased.

Experimental Example 10

In order to confirm that the electron mobility and oxygen reoxidation characteristics of the catalyst exhibit excellent denitrification efficiency at low temperatures, the SCR reaction was confirmed by injecting relatively low concentration of oxygen, and the results are shown in FIG. 9 . As for the analysis conditions, 1000 ppm of ammonia was pre-adsorbed at 250 ^o C, which is a relatively low temperature, and then 1000 ppm NO and 200 ppm O ₂ were injected to confirm the progress of the SCR reaction. In order to confirm the progress of the SCR reaction cycle according to the antimony/titania carrier manufacturing method, Preparation Example 2 and Comparative Preparation Example 3 were compared. The analysis result of Comparative Preparation Example 3 is shown in Fig. 9(a) , and the analysis result of Preparation Example 2 is shown in Fig. 9(b) . As a result, in the case of Preparation Example 2 using antimony/titania as a carrier, the SCR cycle was able to proceed quickly, and after about 3 minutes, all the adsorbed NH ₃ was reacted and NO species started to be adsorbed. However, in the case of Comparative Production Example 3 supported simultaneously with vanadium, it was not until about 7 minutes that all of the adsorbed NH ₃ reacted and NO species started to be adsorbed. That is, it was confirmed that the catalyst of Preparation Example 2 using antimony/titania as a carrier rapidly reacted with a trace amount of oxygen to exhibit excellent activity.

Experimental Example 12

Thermal stability was evaluated according to the addition of antimony to a vanadium/titania catalyst. The heat treatment was carried out under general air conditions for 10 hours at 600 ^o C for Comparative Preparation Example 4, which is a general vanadium-based catalyst, and Preparation Example 2 and Comparative Preparation Example 3 to which antimony was added to Raman to confirm the change in the crystal structure of vanadium. performing analysis is shown in Fig. First, the initial catalyst that was not heat-treated was called'Fresh', and the catalyst that was heat-treated at 600 ^o C for 10 hours was called'Aging' catalyst. As a result, in the case of Comparative Production Example 4, which is a catalyst to which antimony was not added, it was confirmed that the form of V ₂ O ₅ of the crystalline species, which is a clustered form of vanadium, was greatly developed after heat treatment. However, in the case of the catalysts of Preparation Example 2 and Comparative Preparation 3 to which antimony was added, it was confirmed that the structure of vanadium did not change significantly even after the antimony was added, and this was the formation of ₄ types of VxSbyO, which is a binding species of vanadium and antimony, between vanadiums. It was confirmed that the formation of crystalline V ₂ O ₅ was suppressed by suppressing the aggregation phenomenon. Through this, in general, when a vanadium-based catalyst is applied, a phenomenon in which the activity of the catalyst is deteriorated due to exposure to high heat occurs. It is believed that the deteriorated shape of vanadium can be suppressed through the addition of antimony.

Experimental Example 16

In order to evaluate the activity according to the addition of a cocatalyst in the production of a platinum/antimony/titania catalyst for removing gaseous carbon monoxide according to the present invention, carbon monoxide in the reaction temperature range of 100 to 300 ^o C for Preparation Example 9 and Comparative Preparation Example 6 The removal rate was measured. In this case, the concentration of carbon monoxide is 10,000 ppm, the oxygen concentration is 15%, and the moisture content is 8 vol. %, and the space velocity was measured while maintaining at 160,000 h ^{- 1} . Fig. 15 shows the experimental results. As a result, Preparation Example 9 exhibited an efficiency of 100% based on 150 ^o C, and exhibited an efficiency of 85% based on 100 ^o C, but 150 ^o C in Comparative Preparation 6 without using an antimony/titania carrier. It showed 98% of the standard, and showed an efficiency of 66% based on 100 ^o C. Through this, it was confirmed that the catalyst prepared through the antimony/titania carrier exhibited excellent activity up to a low temperature. It was confirmed that the catalyst prepared through the antimony/titania carrier increased the oxygen mobility of platinum, thereby increasing the carbon monoxide removal efficiency.

Experimental Example 17

For Preparation Example 9 and Comparative Preparation Example 6 using an antimony/titania carrier, durability tests for SO ₂ were performed with a catalyst prepared through platinum and platinum/antimony/titania. In this case, the concentration of carbon monoxide was 10,000 ppm, the oxygen concentration was 15%, and the moisture content was 8 vol.%, and the SO ₂ concentration was 500 ppm and the space velocity was maintained at 160,000 h ^{- 1} . Fig. 16 shows the experimental results. As a result, in the case of Preparation Example 9, the initial efficiency was maintained, but in the case of Comparative Preparation Example 6, it was confirmed that it fell to 20% compared to the initial efficiency in 30 minutes. Accordingly, in the case of Preparation Example 9, it was confirmed that the durability against SO ₂ was significantly increased, and it was determined that the catalyst life could be extended with excellent durability in treating carbon monoxide in a gas phase containing a sulfur component.

Claims (12)

Titania (TiO ₂ ) Antimony (Sb) based on 100 parts by weight of antimony (Sb) is supported in titania (TiO ₂ ) to contain an antimony precursor in an amount of 0.3 to 5 parts by weight and calcined at 550 to 650°C. delete The method of claim 1, wherein the antimony precursor is antimony chloride (SbCl ₃ ,), antimony acetate ((CH ₃ CO ₂ ) ₃ Sb), antimony nitrate (2Sb ₂ O ₃ N ₂ O ₅ )), antimony sol (Sb ₂ O ₄ ), characterized in that any one of antimony / tinatia carrier. A reduction catalyst comprising 0.3 to 4 parts by weight of vanadium (V) based on 100 parts by weight of the antimony/titania carrier according to claim ₁ , and having a bonding structure of VSbO ₄ . delete A method for producing a reduction catalyst, characterized in that it is prepared by sintering at 400 to 500°C by supporting a vanadium precursor so as to be 0.3 to 4 parts by weight of vanadium (V) based on 100 parts by weight of the antimony/titania carrier according to claim 1. delete delete delete An oxidation catalyst comprising 0.1 to 3 parts by weight of platinum (Pt) based on 100 parts by weight of the antimony/titania carrier according to claim 1. A method for producing an oxidation catalyst, characterized in that it is prepared by sintering at 400 ^o C by supporting a platinum precursor to 0.1 to 3 parts by weight of platinum (Pt) based on 100 parts by weight of the antimony/titania carrier according to claim 1. delete

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