KR102742636B1 - SCR catalyst using single-step hexagonal boron nitride with improved thermal stability and method for synthesizing the same - Google Patents

Abstract

The present invention relates to an SCR catalyst utilizing hexagonal boron nitride with improved thermal stability and a method for producing the same, and more particularly, to the simultaneous production of porous surface modification and catalyst material synthesis by utilizing two-step heat treatment temperatures.
If the catalyst utilizing the transition metal of the present invention is utilized in other fields together with h-BN, it is possible to manufacture a highly active catalyst by maintaining excellent performance and phase stability compared to existing catalysts by increasing the active site through improving the surface properties of the catalyst and dispersing the catalytically active material. In addition, the present invention is a technology related to an SCR catalyst, and is a technology applicable to exhaust gas treatment facilities in various industrial fields such as fixed sources (power plants, incinerators) and mobile sources (automobiles, ships) of various pollution sources. In the future, if the detailed variables for the manufacturing process for pilot scale and the enhancement of performance and properties are improved, it can be applied to various industries such as petrochemicals in addition to the atmospheric environment.

Description

Selective catalytic reduction (SCR) catalyst using single-step hexagonal boron nitride with improved thermal stability and method for synthesizing the same {SCR catalyst using single-step hexagonal boron nitride with improved thermal stability and method for synthesizing the same}

The present invention relates to an SCR catalyst utilizing hexagonal boron nitride with improved thermal stability and a method for producing the same, and more particularly, to the simultaneous production of porous surface modification and catalyst material synthesis by utilizing two-step heat treatment temperatures.

As attention has recently been focused on the atmospheric environment, various regulations (such as EURO6, Tier III, and special measures for fine dust) on gaseous pollutants emitted from fixed and mobile sources are being strengthened. Accordingly, various technologies are being studied to satisfy regulations. Nitrogen oxides (NO _x ), one of the well-known air pollutants, are very harmful to the human body in themselves, but are also the main cause of fine dust, smog, and acid rain. There are various technologies to remove nitrogen oxides, but SCR (Selective Catalytic Reduction) is the most efficient and representative one. SCR technology is a technology that uses reducing agents, NH ₃ and urea, to change nitrogen oxides (NO _x ) into nitrogen and water vapor, which are harmless to the human body. Currently, SCR catalysts applied to various pollutants use _{V2O5 - WO3} as a catalytic active material based on a _TiO2 support, but there is a problem of reduced efficiency in thermodynamic and economic aspects because they are used in a high temperature range of 300~380℃.

Republic of Korea Patent No. 10-2216948

In order to solve the above problems, the present invention aims to provide a single step synthesis of an SCR catalyst having a wide temperature range and improved thermal stability.

In addition, the present invention aims to provide an SCR catalyst including hexagonal boron nitride synthesized in the single step.

In order to achieve the above purpose, the present invention comprises a first step of preparing solution 1 by dissolving precursor 1 including catalytically active material 1 in a solvent, and preparing solution 2 by dissolving precursor 2 including catalytically active material 2 in a solvent;

A second step of preparing solution 3 by dispersing hexagonal boron nitride as a support in a solvent;

Step 3: preparing solution 4 by dispersing titanium dioxide, a commercial carrier, in a solvent;

A fourth step of mixing the above solutions 1 and 2 into solution 3 to create a mixed solution, and mixing the mixed solution with solution 4;

A fifth step of catalytic etching the surface of hexagonal boron nitride by heat treatment at 250 to 400°C; and

A method for synthesizing a selective catalytic reduction (SCR) catalyst utilizing single step hexagonal boron nitride is provided, including a sixth step of generating an oxide including catalytically active materials 1 and 2 by heat treatment at 330 to 470°C.

In order to achieve the other objects described above, the present invention provides an SCR catalyst having a wide temperature range manufactured by the catalyst synthesis method described above.

If the catalyst utilizing the transition metal of the present invention is utilized in other fields as well as h-BN, it is possible to manufacture a highly active catalyst by maintaining excellent performance and phase stability compared to existing catalysts by increasing the active site through improvement of the surface properties of the catalyst and dispersion of the catalytically active material. In addition, oxides utilizing the transition metal (VOx, WOx, MnOx, CeOx, CoOx) In the case of h-BN, surface modification of the porous surface is possible and it can be used as a catalyst. Therefore, it can be used regardless of the field as long as the material condition of using a transition metal is met.

In addition, the present invention is a technology related to SCR catalysts, and is a technology applicable to exhaust gas treatment facilities in various industrial fields such as fixed sources (power plants, incinerators) and mobile sources (automobiles, ships) of various pollution sources. In the future, if detailed variables for manufacturing processes for pilot scale and performance and property enhancement are improved, it can be applied to various industries such as petrochemicals in addition to the atmospheric environment.

FIG. 1 is a graph showing the measurement of denitrification efficiency using samples obtained after heat treatment by supporting 1 wt% V + 5 wt% W on various forms of h-BN and TiO2 according to one embodiment of the present invention.
FIG. 2 is an image showing the results of TEM, STEM, and EDS analysis of a single step V1W5/BN-TiO ₂ according to one embodiment of the present invention.
FIG. 3 is a graph showing the thermal stability of single step V1W5/BN-TiO ₂ (Example 1) and 2step VW/BN-TiO ₂ (Comparative Example 2) according to one embodiment of the present invention.
Figure 4 is a schematic diagram showing an improvement of a two-step synthesis into a single step according to one embodiment of the present invention.
FIG. 5 is a schematic diagram of a method for synthesizing a denitrification catalyst using single-step hexagonal boron nitride and heat treatment conditions according to one embodiment of the present invention.

The present invention is described in more detail below.

The development of a new catalyst composition is difficult to commercialize immediately because it is accompanied by modifications to the production line and application system line for actual field application, which is difficult in terms of time and economy. Since the SCR catalyst continuously heats the exhaust gas in order to enhance the reactivity, it is an environment easily exposed to heat. Accordingly, when a large amount of catalytic active material is used, phase change and agglomeration phenomenon due to decreased thermal stability occur relatively easily. In other words, the phase change of the main catalyst material and particle agglomeration have a negative effect on the surface properties such as the specific surface area and the decrease in the catalytic acid site, which reduces the catalytic efficiency. To solve these problems, a third material, h-BN (hexagonal boron nitride), is utilized to ensure the thermal stability of the active material, thereby preventing phase change, and at the same time, surface modification of h-BN by a catalytic material is also performed simultaneously to induce the surface into a porous structure, and the catalytic material remains in the pores thus created and is immediately stabilized as an oxide and utilized as a catalyst, which suppresses aggregation and increases dispersibility, and through this, a synergistic effect is obtained in which the catalytic material has dispersibility and stability due to surface modification of h-BN by the catalytic material and the surface-modified h-BN in this way. In addition, although the surface modification of the porous structure of h-BN and the synthesis of a catalyst using porous h-BN (porous h-BN, pBN) are generally separate processes and are performed in two steps (2 steps), the technology of the present invention combines the surface modification of the porous structure and the synthesis of a catalyst using it into a single step through control in the heat treatment step, thereby shortening the process time, and the performance of the synthesized catalyst is similar to that of a catalyst synthesized through the 2-step process.

Boron nitride is a material with various structures (hexagonal, cubic, and wurtzite) and has various properties such as high thermal stability. Among them, the hexagonal structure is a 2D material in a plate shape. h-BN has a high melting point of 2970℃ and is a stable material that maintains its properties up to 1000℃ in air, and research is being conducted in various fields recently. Using these properties, h-BN is utilized as a support for catalytically active materials to improve the efficiency and properties of SCR catalysts through surface modification by suppressing phase change and aggregation and enhancing dispersibility.

In addition, the h-BN undergoes catalytic etching by the transition metal, which causes the h-BN to have a porous structure on the surface, and when the transition metal is positioned in these pores, it has high dispersibility. In the case of a catalyst utilizing a transition metal, the dispersibility is improved and the thermal phase is stabilized to suppress the agglomeration phenomenon by the h-BN surface-modified into a porous structure through the application of the 2D material, h-BN. As a result, even though the same h-BN was used, the effect and performance can be confirmed by comparing the catalyst heat-treated including 300 to 400℃ where catalytic etching occurs with the catalyst that does not include this heat treatment step, and it can be confirmed that it exhibits performance similar to or superior to that of the catalyst using the porous h-BN that was previously manufactured. Through the present invention, surface modification of h-BN using a catalytic material and utilization of the catalyst can be performed in a single process, so that surface modification and catalyst synthesis are possible in a single step.

If the catalyst utilizing the transition metal of the present invention is utilized in other fields as well as h-BN, it is possible to manufacture a highly active catalyst by maintaining excellent performance and phase stability compared to existing catalysts by increasing the active site through improvement of the surface properties of the catalyst and dispersion of the catalytically active material. In addition, oxides utilizing the transition metal (VOx, WOx, MnOx, CeOx, CoOx) In the case of h-BN, surface modification of the porous surface is possible and it can be used as a catalyst. Therefore, it is a technology with a high possibility of being used regardless of the field as long as the material condition of using a transition metal is met.

A first step of preparing solution 1 by dissolving precursor 1 containing catalytically active substance 1 in a solvent, and preparing solution 2 by dissolving precursor 2 containing catalytically active substance 2 in a solvent;

According to one aspect of the present invention, there is provided a method of producing a catalyst, comprising: a first step of dissolving precursor 1 including catalytically active material 1 in a solvent to prepare solution 1, and dissolving precursor 2 including catalytically active material 2 in a solvent to prepare solution 2; a second step of dispersing hexagonal boron nitride as a support in a solvent to prepare solution 3; a third step of dispersing titanium dioxide as a commercial carrier in a solvent to prepare solution 4; a fourth step of mixing solution 1 and solution 2 in solution 3 to prepare a mixed solution, and mixing the mixed solution with solution 4; a fifth step of performing a heat treatment at 250 to 400°C to perform catalytic etching on the surface of hexagonal boron nitride; The present invention provides a method for synthesizing a selective catalytic reduction (SCR) catalyst using single step hexagonal boron nitride, including a sixth step of generating an oxide including catalytically active materials 1 and 2 by heat treatment at 330 to 470°C.

At this time, it is preferable that the solvent is ethanol.

The above single step can also be expressed as a one step, 1step SCR catalyst synthesis method.

In the fifth step, the surface of the hexagonal boron nitride may further include a porous structure through catalytic etching. The temperatures of the fifth and sixth steps are preferably different by 30 to 100°C, more preferably different by 30 to 70°C, and most preferably different by 40 to 60°C. Preferably, the temperature of the fifth step is 310 to 410°C, and the temperature of the sixth step is 340 to 460°C, and more preferably, the temperature of the fifth step is 330 to 380°C, and the temperature of the sixth step is 370 to 440°C. If the temperatures of the fifth and sixth steps are different by 40 to 60°C, there is no significant problem. At the temperature of the fifth step, surface modification into a porous material is promoted through catalytic etching, and in the sixth step, heat treatment is performed at a higher temperature than that of the fifth step to complete the synthesis of the catalytic material. The one-step process shortens the process time and process compared to the conventional two-step process, and since porous surface modification and synthesis of catalyst material are possible with a single synthesis method, it also improves the economic aspect. The SCR catalyst synthesized in this way shows high denitrification efficiency at low and high temperatures, and has a very wide usable temperature range of 200 to 450°C. In addition, the denitrification efficiency shows an efficiency of 94.1 to 99.9% at 220 to 400°C among this temperature range.

A catalyst is largely composed of a catalytically active substance that exhibits catalytic activity, a cocatalyst that improves catalytic activity or extends the life of the catalyst, and a carrier that supports the catalytically active substance and cocatalyst and provides a high surface area to increase the reaction area, i.e., a support. The conditions that the support, which plays a very important role in the use of the catalyst, must have are that it must have a large surface area and contact area due to its application characteristics, and the heat capacity and thermal expansion coefficient of the material must be low. In addition, the operating temperature, strength, and oxidation resistance must be high, and the coating properties and compatibility of the support and the catalyst must be good.

The catalytically active material is preferably a transition metal oxide and may include at least one of oxides of Mn, Ce, Co, Zr, V, and W. VOx, WOx, MnOx, CeOx, CoOx It can be, and can include one or more of MnO, MnO ₂ , Mn ₂ O ₃ , Mn ₃ O ₄ , CeO ₂ , Co ₃ O ₄ , ZrO ₂ , V ₂ O ₅ , and WO ₃ . In the present invention, it is preferable that the catalytically active material 1 and the catalytically active material 2 are synthesized at a mass ratio of 1:1 to 10. More preferably, they are synthesized at a mass ratio of 1:1 to 7.

The precursor may be Ammonium metavanadata (AMV) or Vanadium chloride for VOx, Ammonium metatungstate (AMT) or Tungsten sulfide for WOx, Manganese nitrate hydrate, Manganese acetate dihydrate or Manganese chloride for MnOx, Cerium nitrate hydrate, Cerium acetate hydrate or Cerium chloride for CeOx, Cobalt nitrate hydrate, Cobalt acetylacetonate or Cobalt chloride hexahydrate for CoOx, etc. used in the SCR catalyst containing hexagonal boron nitride.

Any commercial carrier can be used, titanium oxide TiO ₂ is preferred, aluminum oxide Al ₂ O ₃ or silicon oxide SiO ₂ can also be used. TiO ₂ can be used in solid powder form, and hexagonal boron nitride powder is prepared as solutions in different ethanol solvents to prepare four solutions, and then the solutions are combined to synthesize. First, solutions 1, 2, and 3 are mixed, and solution 4 is mixed with the mixed solution. At this time, solutions 1 and 2 are stirred until completely dissolved, and in order to disperse solutions 3 and 4, these solutions can be ultrasonically dispersed for 1 to 2 hours.

According to another aspect of the present invention, a selective catalytic reduction (SCR) catalyst manufactured by the synthetic method of the present invention is provided.

Selective Catalytic Reduction (SCR) is a method of purifying exhaust gas by contacting it with an SCR catalyst. With the help of the SCR catalyst, nitrogen oxides (NOx) in the exhaust gas are converted into nitrogen and water, which are harmless to the human body, and then discharged. At this time, ammonia (NH3) or urea is used as a reducing agent, and the reducing agent is sprayed onto the catalyst heated to a high temperature to selectively reduce only nitrogen oxides in the exhaust gas.

There are various types of SCR catalysts, such as metal oxide, zeolite, alkaline earth metal, and rare earth catalysts, but a monolithic honeycomb extruded catalyst in which sulfated TiO ₂ is used as a carrier and catalytically active materials such as WO ₃ , V ₂ O ₅ , and MoO ₃ are combined has been commercialized. However, these honeycomb monolithic catalysts are expensive due to the utilization of TiO ₂ used as a carrier and catalytically active materials such as WO ₃ and V ₂ O ₅ , and compared to other carrier materials, there is a problem in that the cost of producing the catalyst is high due to the poor formability.

It is preferable that the SCR catalyst of the present invention exhibits NOx removal activity at a temperature of 200 to 450° C. More preferably, the temperature range may be 220 to 420° C. In addition, within the above range, the NOx conversion rate may be 90.0 to 99.9%, and more preferably, the NOx conversion rate may be 94.0 to 99.8%.

The SCR catalyst of the present invention preferably contains 0.1 to 5 wt% of a catalytically active material 1, 1 to 10 wt% of a catalytically active material 2, 5 to 15 wt% of hexagonal boron nitride, and 80 to 90 wt% of TiO _2. The diameter of the SCR catalyst of the present invention is preferably 10 nm to 10 μm, and more preferably, the diameter may be 10 nm to 1 μm. At this time, the thickness of the SCR catalyst is preferably 1 to 200 nm, and more preferably 30 to 100 nm.

In this specification, when a part is said to "include" a certain component, this does not mean that other components are excluded, unless otherwise specifically stated, but that other components may be included. In addition, the terminology used in this specification is for the purpose of describing embodiments, and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated in the phrase.

In this document, the expressions "A or B," "at least one of A and/or B," or "one or more of A or/and B" can include all possible combinations of the listed items. For example, "A or B," "at least one of A and B," or "at least one of A or B" can all refer to (1) including at least one A, (2) including at least one B, or (3) including both at least one A and at least one B.

Hereinafter, the present invention will be described in more detail by way of preferred embodiments. However, it will be apparent to those skilled in the art that these embodiments are intended to explain the present invention more specifically and that the scope of the present invention is not limited thereby.

<Example>

Example 1 - Synthesis of single step V1W5/BN-TiO ₂ (350-400℃)

Catalytically active materials (Vandaium, Tungsten), TiO ₂ powder, and h-BN powder were prepared as solutions using different ethanol solvents. Solution 1 was prepared by dissolving the precursors, Ammonium metavanadata (AMV), NH ₄ VO _{3 ,} in ethanol. Solution 2 was prepared by dissolving the precursors, Ammonium metatungstate (AMT), (NH ₄ ) ₆ H ₂ W ₁₂ O ₄₀ , in ethanol.

Additional support, h-BN powder, was dispersed in ethanol to prepare solution 3. Commercial support, TiO ₂ powder, was dispersed in ethanol to prepare solution 4. Both solutions 1 and 2 were string-treated until completely dissolved. Ultrasonication was performed for 1 h to disperse both solutions 3 and 4. Each dissolved and dispersed solution 1-4 was reacted and supported at 70°C for 2 h, and then at room temperature (RT) for 2 h. Solutions 1 and 2 were poured into 3, combined, and maintained at 70°C for 2 h. The combined solution of solutions 1, 2, and 3 was combined into solution 4, and maintained at room temperature for 2 h. The combined solution of solutions 1, 2, 3, and 4 was stirred while drying in an oil bath at 78°C to evaporate the ethanol.

The porous structure was induced through catalytic etching on the h-BN surface by heat treatment at 350°C in air atmosphere. The VW/BN-TiO ₂ (350-400°C) catalyst was synthesized by thermal stabilization of vanadium (V) and tungsten (W) through heat treatment at 400°C in air atmosphere to form oxides.

Example 2

(1) Denitrification efficiency evaluation experiment

Fixed bed was utilized to evaluate the denitrification efficiency. 0.5 ml of the synthesized catalyst was installed in a 1/2 inch reactor. After that, the gas concentration was adjusted to 300 ppm NO, NH3, SO2 and 5% O2 using MFC in the bypass state so that the gas did not pass through the sample, and N2 was used as the balanced gas to maintain the total flow rate at 500 sccm. When the gas concentration was stabilized, the gas was passed through the reactor equipped with the sample, and the denitrification efficiency of the synthesized catalyst was evaluated while increasing the temperature from 200 to 400℃.

(2) Method for calculating airspeed

item black eye unit Total flow, Total flow 500 sccm Volume of Catalyst, Synthetic catalyst usage 0.5 ml

Based on Table 1 above, the airspeed (space velocity, GHSV: Gas Hourly Space Velocity) was calculated as follows.

The air speed and the denitrification efficiency of the catalyst are inversely proportional. The catalytic denitrification evaluation method usually calculates the ratio of the reaction gas before and after contact with the catalyst by flowing the reaction gas to the catalyst. When the speed of the reaction gas is slow (when the air speed is low), the contact time with the catalyst increases, and accordingly, the reaction time with the catalyst increases, providing an environment in which more gas reacts. Therefore, the air speed and the denitrification efficiency are inversely proportional.

Comparative Example 1 - Synthesis of V1W5/TiO ₂ (400°C) - Catalyst without h-BN

AMV, AMT, and TiO ₂ were mixed with ethanol solvent to have a content of 1 wt% V + 5 wt% W and stirred at 70°C for 2 hours. After drying in an oil bath at 78°C, the mixture was calcined at 400°C for 5 hours at a heating rate of 5°C/min to synthesize V1W5/TiO ₂ (400).

Comparative Example 2 - Synthesis of V1W5/BN-TiO ₂ (400°C) - Catalyst using h-BN but without catalytic etching

Pristine h-BN, AMV, AMT, and TiO ₂ were mixed with ethanol solvent so that the content was 1 wt% V + 5 wt% W and the content ratio of pristine h-BN and TiO ₂ was 1:9, and stirred at 70°C for 2 hours. After drying in an oil bath at 78°C, V1W5/BN-TiO ₂ (400) was synthesized by calcining at 400°C for 5 hours at a heating rate of 5°C/min.

Comparative Example 3 - Synthesis of V1W5/p-BN-TiO ₂ (400°C) - Catalyst with porous effect achieved using porous h-BN

Pristine h-BN was mixed with cobalt precursor and ethanol solvent, stirred at 70°C for 30 minutes, and then the solvent was completely evaporated by evaporation. The heating rate was 5°C/min, and the mixture was calcined at 350°C for 3 hours. After catalyst etching, cobalt oxide, CoOx, was dissolved in an HCl aqueous solution and ionized. After removing all impurities through washing and filtration, the mixture was dried in an oven at 80°C to produce porous h-BN (p-BN).

p-BN, AMV, AMT, and TiO ₂ , which were manufactured to have a content of 1 wt% V + 5 wt% W, were mixed with ethanol solvent and stirred at 70°C for 2 hours. After drying at 78°C in an oil bath, they were calcined at 400°C for 5 hours to synthesize V1W5/p-BN-TiO ₂ (400°C).

pBN is an abbreviation for porous h-BN and was used for comparison with pristine h-BN and single step BN.

<Results and Evaluation>

Denitrification efficiency results

FIG. 1 is a graph showing the measurement of denitrification efficiency using samples obtained after heat treatment by supporting 1 wt% V + 5 wt% W on various forms of h-BN and TiO ₂ according to one embodiment of the present invention.

The numerical values of Fig. 1 are shown in Table 2 below.

NOx conversion (%) Temperature (℃) 200 220 240 250 280 300 350 400 Comparative Example 1 36.4 45.0 53.4 56.2 - 77.4 90.2 89.5 Comparative Example 2 60.8 80.7 93.9 - 99.4 98.8 97.2 90.8 Comparative Example 3 54.3 88.4 91.6 - 95.1 98.8 98.7 97.8 Example 1 75.9 94.1 99.1 99.8 99.8 99.0 98.1 95.9

The heat treatment of each catalyst is shown in Table 3 below.

Comparative Example 1 1 wt% V + 5 wt% W was supported on TiO ₂ and heat treated at 400°C Comparative Example 2 1 wt% V + 5 wt% W supported on BN and TiO ₂ and heat treated at 400°C Comparative Example 3 Heat treatment at 400°C when 1 wt% V + 5 wt% W is deposited on pBN and TiO ₂ Example 1 A single step catalyst was obtained by heat-treating samples at 350°C and 400°C when 1 wt% V + 5 wt% W was supported on BN and TiO _2.

Referring to FIG. 1, Table 2, and Table 3, it was confirmed that the SCR catalyst characteristics were improved by applying h-BN when comparing Comparative Examples 1 and 2. It was confirmed that the efficiency increased by approximately 35.7%, from 45.0% to 80.7% at 240℃. When Comparative Examples 2 and 3 are compared, the effects of pristine h-BN and porous h-BN (2step) on the catalyst can be confirmed, and it was confirmed that the SCR catalyst characteristics were further improved when the porous structure was applied. It was confirmed that the efficiency increased by approximately 7.7%, from 80.7% to 88.4% at 240℃. Comparing Comparative Example 3 and Example 1, the effect of a single step can be confirmed, and the catalyst synthesized using pristine h-BN in a single step shows higher efficiency at low temperatures (based on 350) and similar values at high temperatures than the two-step catalyst using porous h-BN, confirming the effect of a single step.

Results of increased dispersion

FIG. 2 is an image showing the results of TEM, STEM, and EDS analysis of a single step V1W5/BN-TiO ₂ according to one embodiment of the present invention. Referring to FIG. 2, it can be seen that transition metals, vanadium (V) and tungsten (W), are evenly dispersed on h-BN.

Thermal stability results

FIG. 3 is a graph showing the thermal stability of single step V1W5/BN-TiO2 (Example 1) and 2step VW/BN-TiO ₂ (Comparative Example 2) according to one embodiment of the present invention.

Referring to Fig. 3, the thermal stability was evaluated by continuously exposing the synthesized catalyst to heat for 600 minutes (10 hours) through continuous measurement. In the case of the catalyst synthesized in a single step at 240°C, the catalytic efficiency due to deterioration decreased by only 2%, and considering that the catalyst using only the existing pristine h-BN had a 7% decrease, it was confirmed that the thermal stability was improved.

The foregoing has broadly described the features and technical advantages of the present invention so that the scope of the claims to be described later may be better understood. Those skilled in the art will appreciate that the present invention may be implemented in other specific forms without changing the technical idea or essential features thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the claims and their equivalents should be interpreted as being included in the scope of the present invention.

Claims (8)

A first step of preparing a vanadium solution (solution 1) by dissolving a vanadium (V) precursor in ethanol and a tungsten solution (solution 2) by dissolving a tungsten (W) precursor in ethanol;
A second step of preparing a hexagonal boron nitride solution (solution 3) by dispersing hexagonal boron nitride as a support in ethanol;
A third step of preparing a titanium dioxide solution (solution 4) by dispersing titanium dioxide, a commercial carrier, in ethanol;
A fourth step of mixing a mixed solution of the vanadium solution (solution 1) and the tungsten solution (solution 2) into a hexagonal boron nitride solution (solution 3) with the titanium dioxide solution (solution 4) and drying to evaporate ethanol;
A fifth step of obtaining a porous structure through catalytic etching on the surface of hexagonal boron nitride (BN)-titanium dioxide (TiO ₂ ) by heat treatment at 330 to 380° C; and
A method for synthesizing a catalyst for selective catalytic reduction (SCR) using a single step hexagonal boron nitride, comprising: a sixth step of synthesizing a catalyst (VW/BN-TiO ₂ ) supporting vanadium (V) and tungsten (W) on a hexagonal boron nitride (BN)-titanium dioxide (TiO ₂ ) support by heat treatment at 370 to 440°C;
In paragraph 1,
A method for synthesizing a selective catalytic reduction (SCR) catalyst using single step hexagonal boron nitride, characterized in that the temperatures of the fifth and sixth steps have a difference of 40 to 60°C.
In paragraph 1,
A method for synthesizing a selective catalytic reduction (SCR) catalyst using a single step hexagonal boron nitride, characterized in that the vanadium solution (solution 1) and the tungsten solution (solution 2) are synthesized in a mass ratio of 1:5.
A selective catalytic reduction (SCR) catalyst manufactured by a synthetic method according to any one of claims 1 to 3.
In paragraph 4,
The above catalyst is a selective catalytic reduction (SCR) catalyst characterized by exhibiting NOx removal activity at a temperature of 240 to 400°C.
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