KR102457079B1 - Simultaneous removal system of complex harmful substances - Google Patents

Abstract

Simultaneous removal apparatus, method and system for carbon monoxide (CO) and nitrogen oxides (NO _X ) according to the present invention are carbon monoxide (CO) and nitrogen oxides (NO _X ) at a high conversion rate in a wide temperature range from low to high temperatures. CO ₂ ) or nitrogen (N ₂ ) has the effect of being converted.

Description

Simultaneous removal system of complex harmful substances

The present invention relates to a system for simultaneous removal of carbon monoxide and nitrogen oxides.

Liquefied natural gas (LNG) power generation, which is responsible for the peak load of domestic electricity supply, is expected to steadily increase the capacity of liquefied natural gas power generation facilities by 2030 according to the energy transition policy to eco-friendly power generation to reduce fine dust. to be. Although the level of fine dust emission from liquefied natural gas power generation is 1/8 of that of coal power generation, the amount of nitrogen oxides (NO _x ) emitted during the combustion process of liquefied natural gas is still being applied with additional reduction facilities to satisfy the level of environmental regulations. . The most common flue gas denitrification technology for reducing nitrogen oxide emissions is to use ammonia (NH ₃ ) or urea (CH ₄ N ₂ O) as a reducing agent to convert nitrogen oxides (NO _x ) harmless to human body nitrogen (N ₂ ) in the presence of a metal oxide catalyst. ) and water (H ₂ O), which is a selective catalytic reduction (SCR) method.

However, according to a 2019 survey on the emission of hazardous air pollutants from five power generation companies, large amounts of carbon monoxide (~2,000 ppm), nitrogen dioxide (~70 ppm) and nitrogen monoxide (~80 ppm) was found to be excreted as it is. A high concentration of carbon monoxide is a toxic gas that causes suffocation, and nitrogen dioxide over 10 ppm causes yellow smoke, which is a factor that threatens the health of nearby residents around liquefied natural gas power plants.

At the initial stage of starting liquefied natural gas power generation, it is difficult to reduce a large amount of nitrogen dioxide (NO ₂ ), which is a visible soot-causing substance, as the SCR operation is inappropriate due to the low exhaust gas temperature. Therefore, the ethanol reducing agent injection method (Yellow Plume Elimination System, YPES) is applied to suppress the generation of yellow smoke, but this simply converts nitrogen dioxide (NO ₂ ) into nitrogen monoxide (NO) to suppress the generation of yellow smoke, and the converted high concentration Nitric oxide (NO) is discharged as it is. Therefore, there is a limit to satisfy the tightened nitrogen oxide (NO _X ) emission regulation, and there is a problem of generating additional air pollutants such as formaldehyde, a carcinogen, when ethanol is sprayed.

In particular, there are no carbon monoxide emission reduction facilities in domestic power plants because carbon monoxide (CO), which is emitted in large quantities at the beginning of operation, is not subject to reduction as unregulated air pollutants in domestic power plants, unlike overseas. However, after the recent issue of high-concentration unregulated air pollutants has become an issue, the demand for carbon monoxide (CO) emission reduction facilities along with nitrogen oxides is increasing. However, it is difficult to apply additional carbon monoxide (CO) reduction facilities due to the spatial restrictions inside the Heat Recovery Steam Generator (HRGS) of the current liquefied natural gas power plant, and there is no reduction technology that can be applied when constructing a new power plant. situation.

As such, in order to preemptively respond to the strengthened emission regulations, it is essential to develop advanced technologies that can efficiently and effectively remove a large amount of harmful air pollutants, particularly carbon monoxide (CO) and nitrogen oxides (NO _X ) at the same time.

Furthermore, it is required to develop a catalyst system capable of simultaneously reducing and removing air pollutants including carbon monoxide (CO) and nitrogen oxides (NO _X ) effectively from a low temperature (160°C) to a high temperature (400°C).

Korean Patent Registration No. 10-1091705 (2011.12.02)

An object of the present invention is to provide an apparatus, method and system capable of simultaneously reducing and removing gases including carbon monoxide (CO) and nitrogen oxides (NO _X ).

Another object of the present invention is a device capable of converting carbon monoxide (CO) and nitrogen oxide (NO _X ) into carbon dioxide (CO ₂ ) and nitrogen (N ₂ ) at a high conversion rate in a wide temperature range from low temperature to high temperature, a method and provide the system.

Simultaneous removal apparatus for carbon monoxide and nitrogen oxides according to the present invention, a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is introduced, and converted to carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by the first catalyst a first reaction unit to be; And ammonia (NH ₃ ) is introduced, a fluid containing nitrogen monoxide (NO) is introduced from the first reaction unit, and the nitrogen monoxide (NO) is reacted with the ammonia (NH ₃ ) by a second catalyst A second reaction unit that is converted into nitrogen (N ₂ ) and water (H ₂ O); includes, wherein the first catalyst includes a support on which an active metal including a platinum group transition metal is supported. and the second catalyst is any one selected from Gd, V, Mn, Co, Ni, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu A nitrogen oxide reduction catalyst comprising a support on which an active metal containing one or more is supported, wherein the support of the first catalyst and the support of the second catalyst are each independently aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide , including any one or two or more selected from cerium oxide, silicon oxide and carbon.

In one embodiment of the present invention, in the first catalyst, the platinum group transition metal of the active metal may include Pt, and the support may include aluminum oxide and titanium oxide.

In an example of the present invention, in the second catalyst, the active metal may include Gd and V, and the support may include titanium oxide.

In an example of the present invention, the support of the first catalyst or the support of the second catalyst may have a BET specific surface area of 100 m ² /g or more.

In an example of the present invention, the fluid of the first reaction unit may be a complex harmful gas discharged from a liquefied natural gas power generation system.

An internal combustion power generation system according to the present invention includes the device for simultaneously removing carbon monoxide and nitrogen oxides, and includes: an internal combustion engine in which fuel and air are introduced and combusted to drive a gas turbine; a power generation engine converting kinetic energy of the gas turbine into electrical energy; and the device through which the combustion gas discharged from the internal combustion engine flows into the first reaction unit.

The liquefied natural gas power generation system according to the present invention includes the internal combustion power generation system, wherein the fuel is supplied from liquefied natural gas, and the combustion gas is a complex harmful gas containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ). .

The method for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention is a first in which a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is converted into carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by a first catalyst A second reaction step and a fluid containing nitrogen monoxide (NO) that has passed through the first reaction step is converted into nitrogen (N ₂ ) and water (H ₂ O) by reacting with ammonia (NH ₃ ) by a second catalyst A reaction step, wherein the first catalyst is a carbon monoxide-nitrogen dioxide reduction catalyst including a support on which an active metal including a platinum group transition metal is supported, and the second catalyst is Gd, V, Mn, Co, Ni, La , Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and nitrogen oxide comprising a support on which an active metal containing any one or two or more selected from Lu It is a reduction catalyst, and the support of the first catalyst and the support of the second catalyst are each independently selected from aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, cerium oxide, silicon oxide, and carbon. do.

In one embodiment of the present invention, in the first catalyst, the platinum group transition metal of the active metal may include Pt, and the support may include aluminum oxide and titanium oxide.

In an example of the present invention, in the first reaction step, carbon monoxide (CO) conversion and nitrogen dioxide (NO ₂ ) conversion at 125° C. to 175° C. may all be 90% or more.

In an example of the present invention, in the first reaction step, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) may be converted into carbon dioxide (CO ₂ ) or nitrogen monoxide (NO) at 200° C. or less, and 300° C. or less In carbon monoxide (CO) can be converted to carbon dioxide (CO ₂ ).

In an example of the present invention, in the second catalyst, the active metal may include gadolinium and vanadium, and the support may include titanium oxide.

In an example of the present invention, in the second reaction step, the nitrogen monoxide (NO) conversion rate at 200° C. or higher may be 90% or more.

In an example of the present invention, the conversion temperature of the first reaction step and the second reaction step may be 100 to 400 ℃.

In an example of the present invention, the first catalyst or the second catalyst is prepared by adding a support to an aqueous active metal precursor solution to prepare a slurry, and calcining the slurry to prepare a catalyst comprising a support on which an active metal is supported. It can be prepared including the step of obtaining.

In an example of the present invention, the support of the first catalyst or the support of the second catalyst may have a BET specific surface area of 100 m ² /g or more.

In an example of the present invention, the fluid of the first reaction step may be a complex harmful gas discharged from a liquefied natural gas power generation system.

The internal combustion power generation method according to the present invention includes a method for simultaneously removing carbon monoxide and nitrogen oxides, comprising: a combustion step of burning fuel to drive a gas turbine; a power generation step of converting kinetic energy of the gas turbine into electrical energy; and a simultaneous removal step of removing carbon monoxide and nitrogen oxides by using the combustion gas generated by the combustion as the fluid of the first reaction step.

The liquefied natural gas power generation method according to the present invention includes the internal combustion power generation method, wherein the fuel is supplied from liquefied natural gas, and the combustion gas is a complex harmful gas containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ). .

Simultaneous removal apparatus, method and system for carbon monoxide (CO) and nitrogen oxides (NO _X ) according to the present invention are carbon monoxide (CO) and nitrogen oxides (NO _X ) at a high conversion rate in a wide temperature range from low to high temperatures. CO ₂ ) or nitrogen (N ₂ ) has the effect of being converted.

1 schematically compares and shows the concept of a technology for simultaneously reducing carbon monoxide and nitrogen oxides according to the present invention with a conventional SCR process.
Figure 2 shows a conceptual diagram of the process of the simultaneous reduction technology of carbon monoxide and nitrogen oxides according to the present invention.
3 is an evaluation result of the conversion rate of carbon monoxide and nitrogen dioxide for each temperature for the first catalyst of Example.
4 is an evaluation result for each temperature under the evaluation condition 1) for the second catalyst of Examples and Comparative Examples.
5 is an evaluation result under evaluation condition 2) for the second catalyst of Examples and Comparative Examples.
6 is an evaluation result for each time under evaluation condition 2) for the second catalyst of Examples and Comparative Examples.
7 is an evaluation result for each time under evaluation condition 3) of the second catalyst of Example 4.
8 is an evaluation result for each time under evaluation condition 4) of the second catalyst of Example 4.

Hereinafter, a system for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention will be described in detail with reference to the accompanying drawings.

The drawings described in this specification are provided as examples in order to sufficiently convey the spirit of the present invention to those skilled in the art. Therefore, the present invention is not limited to the drawings presented and may be embodied in other forms, and the drawings may be exaggerated to clarify the spirit of the present invention.

Unless otherwise defined in technical terms and scientific terms used in this specification, those of ordinary skill in the art to which this invention belongs have the meanings commonly understood, and in the following description and accompanying drawings, the subject matter of the present invention Descriptions of known functions and configurations that may unnecessarily obscure will be omitted.

A singular form of a term used herein may be construed to include a plural form as well unless otherwise indicated.

Unless otherwise specified, the unit of % used in the present specification means % by weight unless otherwise specified.

The present invention relates to a technology capable of simultaneously reducing and removing carbon monoxide and nitrogen oxides. At the initial stage of operation during natural liquefied gas power generation, incomplete combustion of a gas turbine releases nitrogen oxides along with a large amount of carbon monoxide, so carbon monoxide and nitrogen oxides removal is essential. However, until now, only focused on the removal of nitrogen oxides, the technology capable of effectively removing carbon monoxide and nitrogen oxides at the same time has not been studied in depth.

Specifically, referring to FIG. 1 , in the conventional selective catalytic reduction (SCR) technology, it was practically difficult to reduce and remove nitrogen oxides at a low temperature of 200° C. or less. Carbon monoxide emitted along with nitrogen oxides was impossible to remove. At a time when the demand for carbon monoxide emission reduction is increasing recently, the removal of carbon monoxide is essential, so the conventional SCR technology has a clear limit.

Accordingly, the present invention reduces and removes carbon monoxide by oxidizing carbon monoxide to carbon dioxide, and at the same time reduces nitrogen dioxide to nitrogen monoxide and a second reaction process of reducing the reduced nitrogen monoxide to nitrogen and water. By sequentially performing, It provides a technology that can efficiently and effectively reduce and remove nitrogen oxides (NO, NO ₂ ) together with carbon monoxide at a low temperature.

Specifically, through a system in which the first reaction process and the second reaction process in which specific catalysts are applied to a multi-stage reaction, respectively, are combined, a technology that can efficiently and effectively remove carbon monoxide (CO) and nitrogen oxides (NO _X ) at the same time to provide. In the present invention, in order to simultaneously remove both carbon monoxide (CO) and nitrogen oxides (NO _X ) at a high conversion rate, a primary reaction with a first catalyst to be described later reduces and removes carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) at the same time After the first reaction, nitrogen monoxide (NO) converted from nitrogen dioxide (NO ₂ ) by the first reaction is converted into nitrogen (N ₂ ) and water (H ₂ O) by performing a second reaction with a second catalyst By doing so, carbon monoxide (CO) and nitrogen oxides (NO _X ) are simultaneously efficiently and effectively removed at a low temperature.

Referring to FIG. 2 , in the first reaction process, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are reacted to generate nitrogen monoxide (NO), and carbon monoxide (CO) reacts with oxygen (O ₂ ) to react with carbon dioxide (CO ₂ ) ) is created. Therefore, in the first reaction process, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are reduced and removed at the same time, and nitrogen monoxide (NO) generated in the first reaction process is ammonia (NH ₃ ) and reaction in the second process of the second stage. to produce nitrogen (N ₂ ) and water (H ₂ O). As such, by continuously performing the first reaction process and the second reaction process, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are finally carbon dioxide (CO ₂ ) and at a low temperature of 300 ° C. or less, preferably 200 ° C. or less. It is converted with high efficiency to nitrogen (N ₂ ) and water (H ₂ O). At this time, the finally discharged gas is carbon dioxide (CO ₂ ), nitrogen (N ₂ ) and water (H ₂ O), so it is eco-friendly, and nitrogen monoxide (NO) also reacts with the removal of carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) to be removed Therefore, in addition to the aspect that can reduce carbon monoxide (CO) and nitrogen oxides (NO _X ) at the same time, nitrogen dioxide (NO ₂ ) and nitrogen monoxide (NO), which are nitrogen oxides, both can be reduced and removed from the side, which is a very desirable exhaust gas (CO, NO _X ) reduction technology.

Hereinafter, an apparatus for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention will be described in detail.

Simultaneous removal apparatus for carbon monoxide and nitrogen oxides according to the present invention, a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is introduced, and converted to carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by the first catalyst a first reaction unit to be; And ammonia (NH ₃ ) is introduced, a fluid containing nitrogen monoxide (NO) is introduced from the first reaction unit, and the nitrogen monoxide (NO) is reacted with the ammonia (NH ₃ ) by a second catalyst and a second reaction unit that is converted into nitrogen (N ₂ ) and water (H ₂ O). Here, the first catalyst is a carbon monoxide-nitrogen dioxide reduction catalyst including a support on which an active metal including a platinum group transition metal is supported, and the second catalyst is Gd, V, Mn, Co, Ni, La, Ce, Pr, It is a nitrogen oxide reduction catalyst comprising a support on which an active metal containing any one or two or more selected from Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu is supported. In addition, the support of the first catalyst and the support of the second catalyst are each independently aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), magnesium oxide (MgO), zirconium oxide (ZrO ₂ ), cerium oxide ( CeO ₂ ), silicon oxide (SiO ₂ ), and includes any one or two or more selected from carbon (C).

The first reaction unit simultaneously converts carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) into carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) under the first catalyst, respectively. Specifically, a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is introduced into the first reaction unit, and in this case, the fluid is a combustion gas of liquefied natural gas. That is, the combustion gas is generated by the combustion of natural gas in a liquefied natural gas power generation system, which includes carbon monoxide (CO) and nitrogen oxides (NO ₂ , NO). Therefore, when the combustion gas is discharged into the atmosphere as it is, since it causes serious environmental pollution, it is necessary to reduce and remove carbon monoxide (CO) and nitrogen oxides (NO ₂ , NO) in the combustion gas. In particular, in the present invention, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are respectively converted into carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) under the first catalyst in the first reaction unit, and at this time, are simultaneously converted in one reaction space Accordingly, the reaction can be carried out in a relatively simple and small facility space.

Therefore, the first catalyst plays a very important role in the present invention to simultaneously remove carbon monoxide (CO) and nitrogen dioxide (NO ₂ ). The first catalyst is a catalyst for simultaneously reducing carbon monoxide and nitrogen dioxide including a support on which an active metal including a platinum group transition metal is supported, and the platinum group transition metal is ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os). ), any one or two or more selected from iridium (Ir) and platinum (Pt). As a preferred example, in the first catalyst, in reducing and removing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) at the same time, each conversion rate at the same time in a wider temperature range is 90% or more, preferably close to 100% In this aspect, the platinum group transition metal may include platinum (Pt).

In the first reaction unit, carbon monoxide (CO) reacts with oxygen (O ₂ ) under a first catalyst, and nitrogen dioxide (NO ₂ ) reacts with carbon monoxide (CO) in combustion gas to respectively carbon dioxide (CO ₂ ) and nitrogen monoxide ( converted to NO). Oxygen (O ₂ ) is normally included as air in the fluid flowing into the first reaction unit, that is, exhaust gas, and thus reacts to generate carbon dioxide (CO ₂ ).

In the first catalyst, the support is aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), magnesium oxide (MgO), zirconium oxide (ZrO ₂ ), cerium oxide (CeO ₂ ), silicon oxide (SiO ₂ ) and any one or two or more selected from carbon (C). As a preferred example, in the first catalyst, the support includes at least one selected from aluminum oxide and titanium oxide, so that each conversion rate is at least 90%, preferably close to 100% at the same time in a wider temperature range good in terms of In particular, when the support includes both aluminum oxide and titanium oxide, both carbon monoxide (CO) conversion and nitrogen dioxide (NO ₂ ) conversion at the same time in a wider temperature range are 90% or more, preferably close to 100%. desirable.

Therefore, as a very preferred example, when the active metal of the first catalyst includes platinum (Pt), and the support of the first catalyst includes aluminum oxide and titanium oxide, carbon monoxide (CO) conversion rate at the same time in a very wide temperature range And nitrogen dioxide (NO ₂ ) It is very preferable in terms of making it possible to make both the conversion rates close to 100%.

As described above, in the device for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention, in the first reaction step, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are removed, and in particular, carbon monoxide (CO) conversion rate and nitrogen dioxide in a specific temperature range The (NO ₂ ) conversion is remarkably high.

Specifically, the reaction temperature in the first reaction part may be 100 to 400 ℃, preferably 100 to 300 ℃, more preferably 100 to 200 ℃. As a preferred example, in the first reaction step, the carbon monoxide (CO) conversion and the nitrogen dioxide (NO ₂ ) conversion at 120 ° C. to 180 ° C., preferably 125 ° C. to 175 ° C. are all 90% or more, preferably 100%. can be close Also as a preferred example, in the first reaction step, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) at 200° C. or less may be converted into carbon dioxide (CO ₂ ) or nitrogen monoxide (NO), and at 300° C. or less, carbon monoxide ( CO) can be converted to carbon dioxide (CO ₂ ).

In the apparatus according to an embodiment of the present invention, carbon dioxide (CO ₂ ) converted from carbon monoxide (CO) in the first reaction unit may be included in the fluid as it is and may be introduced into the second reaction unit, but with the first reaction unit and It may further include a carbon dioxide discharge line communicating with the carbon dioxide (CO ₂ ) is discharged to the outside of the second reaction unit. In this case, carbon dioxide (CO ₂ ) generated in the first reaction unit may be discharged to a separate discharge line, or a portion may be discharged through the second reaction unit.

The second reaction unit converts nitrogen monoxide (NO) discharged from the first reaction unit into nitrogen (N ₂ ) and water (H ₂ O) under a second catalyst. The second catalyst may be any one capable of converting nitrogen monoxide (NO) into nitrogen (N ₂ ). As nitrogen monoxide (NO) reacts with ammonia (NH ₃ ) by the second catalyst to generate nitrogen (N ₂ ), the apparatus may further include an ammonia supply line communicating with the second reaction unit. In addition, nitrogen monoxide (NO) reacts with oxygen (O ₂ ) together with ammonia (NH ₃ ), or reacts with nitrogen dioxide (NO ₂ ) together with ammonia (NH ₃ ) to be converted into nitrogen (N ₂ ). The apparatus may further include a second air supply line communicating with the second reaction unit. When converted to nitrogen (N ₂ ) by reacting with nitrogen dioxide (NO ₂ ) with ammonia (NH ₃ ), unreacted nitrogen dioxide (NO ₂ ) or nitrogen monoxide (NO) and oxygen (O ₂ ) in the first reaction unit Nitrogen dioxide (NO ₂ ) produced by the reaction may be used.

The device according to an embodiment of the present invention may further include a sensor unit for measuring a nitrogen oxide conversion rate or measuring a carbon monoxide conversion rate.

As described, the second catalyst is capable of converting nitrogen monoxide (NO) into nitrogen (N ₂ ), Gd, V, Mn, Co, Ni, La, Ce, Pr, Nd, Pm, Sm, Eu , Gd, Tb, Dy, Ho, Er, Tm, Yb and is a nitrogen oxide reduction catalyst comprising a support on which an active metal containing any one or two or more selected from Lu. As a preferred example, the active metal of the second catalyst may include Gd and V in terms of achieving excellent catalytic performance even in a low-temperature region and having improved durability and heat resistance compared to the prior art.

In the second catalyst, the support is aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), magnesium oxide (MgO), zirconium oxide (ZrO ₂ ), cerium oxide (CeO ₂ ), silicon oxide (SiO ₂ ) and any one or two or more selected from carbon (C). As a preferred example, in the second catalyst, it may be preferable that the support includes titanium oxide in terms of not only realizing excellent catalytic performance even in a low temperature region, but also having improved durability and heat resistance compared to the prior art.

In this way, nitrogen oxides can be selectively removed at a high conversion rate through the second catalyst in the second reaction unit, and the reaction temperature in the second reaction unit is 100 to 400 °C, preferably 100 to 300 °C, more Preferably it may be 100 to 200 ℃.

Hereinafter, preferred examples of the second catalyst will be described in detail, and the first catalyst will also be described in detail.

As described above, the second catalyst may preferably use titanium oxide as a support (support), and Gd and V are supported in the support, for example, gadolinium-vanadate-supported nitrogen in the support. It may be more preferable that it is a catalyst for oxide reduction. Specifically, the second catalyst may be one represented by the following formula (1), which has the use and function of the low-temperature SCR catalyst.

[Formula 1]

Gd-VO _X /TiO ₂

(In Formula 1, Gd is gadolinium)

The second catalyst according to an embodiment of the present invention may have a nitrogen oxide conversion rate of 50% or more even at a temperature of 250° C. or less. This effect may be the highest value among SCR catalysts based on V-containing catalysts known to date.

For example, the second catalyst according to an embodiment of the present invention may implement a nitrogen oxide conversion rate of 60% or more, or 70% or more, or 80% or more at a temperature of 180°C. In addition, the second catalyst can implement a nitrogen oxide conversion rate of 90% or more at a temperature of 180 ° C., and this effect is a surprisingly remarkable level with an improved effect of 180% or more compared to a commercial catalyst (V/W/TiO ₂ ) corresponds to

For example, the low temperature may be in the range of 250 °C or less, specifically 150 to 250 °C, more specifically 160 to 250 °C, most specifically 180 to 250 °C range.

In the second catalyst according to an embodiment of the present invention, the carrier may have porosity, and specifically may be an anatase type.

The second catalyst according to an embodiment of the present invention realizes high catalytic activity without requiring a high-temperature heat treatment step. In addition, since a high-temperature process is not required, when the carrier is titanium oxide (TiO ₂ ), it is possible to exclude a decrease in the effect due to a phase change thereof.

When the support (carrier) of the first catalyst or the support (carrier) of the second catalyst is titanium oxide, the BET specific surface area may be 100 m ² /g or more. For example, the surface area of the titanium oxide carrier may be 100 m ² /g or more, specifically 250 to 800 m ² /g, and more specifically 300 to 500 m ² /g.

For example, when the support (carrier) of the first catalyst or the support (carrier) of the second catalyst is titanium oxide, the pore size thereof is specifically 0.01 to 20 nm, more specifically 1 to 10 nm. can

When the support (carrier) of the first catalyst or the support (carrier) of the second catalyst is titanium oxide, its total pore volume may be 1.0 cm ³ /g or less, specifically 0.9 cm ³ /g or less, More specifically, it may be in the range of 0.1 to 0.6 cm ³ /g, most specifically 0.3 to 0.5 cm ³ /g.

For example, when the support (carrier) of the first catalyst or the support (carrier) of the second catalyst is titanium oxide, its average particle diameter (D ₅₀ ) may be 0.1 to 100 nm, specifically 1 to 50 nm, and more Specifically, it may have a range of 5 to 20 nm.

The specific characteristics of the above-described support (carrier) are only described as preferred examples, and the present invention is not limited thereto.

The second catalyst according to an embodiment of the present invention may include 9 to 20% by weight of gadolinium-vanadate based on the total weight, specifically 9.5 to 15% by weight, more specifically 10 to 15% by weight It may be included in the % range.

In addition, the second catalyst including gadolinium-vanadate in the above-described weight % range may include 5 to 200 parts by weight of gadolinium based on 100 parts by weight of vanadium. As such, the second catalyst may preferably contain gadolinium in a weight ratio equal to or less than that of vanadium, and in this case, it is more advantageous in conversion to nitrogen oxides.

As a specific example, the second catalyst may contain 5 to 180 moles of gadolinium based on 100 parts by weight of vanadium.

As a specific example, the second catalyst may contain 5 to 150 moles of gadolinium based on 100 parts by weight of vanadium.

In the following examples, the second catalyst contains the gadolinium-vanadate in an amount of 10% by weight based on the total weight, but when vanadium and gadolinium are included in a 9:1 weight ratio, 9V-1.0Gd/TiO ₂ It may be expressed as .

In addition, in the first catalyst or the second catalyst according to an embodiment of the present invention, when the support is titanium oxide, it may be more preferable that the BET specific surface area of the titanium oxide support is controlled through calcination. Specifically, the BET specific surface area after firing relative to the initial BET specific surface area (BET ₁ /BET ₀ ) may be at a level of 0.1 to 0.5. In this case, the BET ₀ is the initial BET specific surface area, and BET ₁ is the BET specific surface area after firing.

As described above, the second catalyst according to an embodiment of the present invention may be substantially composed of Gd-VO _X /TiO ₂ . Accordingly, it is possible to realize more stable catalytic performance and realize stable catalytic performance even under severe conditions. At this time, the harsh conditions may be 1) the presence of moisture, 2) the presence of sulfur dioxide, 3) use for 10 hours or more, 4) repeated temperature change, and 5) a combination thereof.

Hereinafter, a method for preparing the first catalyst and the second catalyst will be described in detail.

The method for preparing the first catalyst or the second catalyst includes the steps of dissolving an active metal precursor to prepare a mixed solution; preparing a slurry by adding a carrier to the mixed solution; and drying and calcining the slurry to prepare a catalyst in which an active metal is supported on the carrier.

First, an active metal precursor is dissolved to prepare a mixed solution. In this case, when two or more kinds of active metal precursors are used, the respective precursor solutions may be mixed and dissolved at once regardless of the order, or may be mixed after preparing each precursor solution. As a preferred example, in the case of a catalyst on which gadolinium-vanadate is supported, after preparing a vanadium precursor solution, the gadolinium precursor may be added and dissolved.

For example, the active metal precursor may be dissolved in an aqueous solution.

When preparing the active metal precursor solution, for example, oxalic acid may be added together to adjust the solubility and pH of the vanadium precursor. By controlling the amount of oxalic acid used, the structure of the active site of the catalyst and the ratio of active lattice oxygen or surface adsorbed oxygen species are different to activate the final catalyst. can increase The amount of the oxalic acid used is not particularly limited, and may be used in an amount of 100 to 200 parts by weight, specifically 110 to 180 parts by weight, and more specifically 120 to 150 parts by weight based on 100 parts by weight of the precursor.

As the active metal precursor, a known active metal precursor may be used. Platinum precursors include, for example, chloroplatinic acid (H ₂ PtCl ₆ ), potassium tetrachloroplatinate (K ₂ PtCl ₄ ), chloroplatinic acid hydrate (H ₂ PtCl ₆ ·xH ₂ O), platinum chloride (Platinum). chloride), platinum acetylacetonate (Platinum acetylacetonate, Pt(C ₅ H ₇ O ₂ ) ₂ )), platinum bromide and platinum diamine dichloride (Pt(NH ₃ ) ₂ Cl ₂ ) Any one selected from Or it may include two or more. Taking vanadium precursor as an example, NH ₄ VO ₃ , NaVO ₃ , VCl ₂ , VCl ₃ , VBr ₃ , VO(C ₅ H ₇ O ₂ ) ₂ , VO(OC ₂ H ₅ ) ₃ , VC ₁₀ H ₁₀ Cl ₂ , VC1 ₈ H ₁₄ I, VOCl ₃ , VOF ₃ , VO(OCH(CH ₃ ) ₂ ) ₃ , V(C5H ₇ O ₂ ) ₃ , VOSO ₄ , V(C ₅ H ₅ ) ₂ and V(C ₅ H ₅ ) ) may be one or a mixture of two or more selected from ₂ and the like. In addition, a hydrate thereof or a solvate thereof may also be an aspect of the second catalyst according to the present invention. Taking the gadolinium precursor as an example, GdCl ₃ , GdF ₃ , Gd(NO ₃ ) ₃ , Gd(CH ₃ CO ₂ ) ₃ , Gd(C ₅ H ₇ O ₂ ) ₃ , Gd ₂ (SO ₄ ) ₃ , Gd( It may be one or a mixture of two or more selected from C ₅ H ₇ O ₂ ) ₃ and Gd(OH) ₃ . In addition, a hydrate thereof or a solvate thereof may also be an aspect of the present invention. Of course, the above-described vanadium precursor and gadolinium precursor may be appropriately adjusted according to the weight ratio of gadolinium and vanadate in the desired catalyst for reducing nitrogen oxides.

As a specific example, taking the gadolinium-vanadate-supported second catalyst as an example, the mixed solution may include 0.01 to 0.4 moles of the gadolinium precursor based on 1 mole of the vanadium precursor. Specifically, the gadolinium precursor may be included in the range of 0.015 to 0.38 moles, more specifically 0.015 to 0.35 moles.

Next, a carrier is added to the mixed solution to prepare a slurry.

When the support (carrier) of the first catalyst or the support (carrier) of the second catalyst is titanium oxide, the support may preferably have a BET specific surface area of 100 m ² /g or more. In addition, in order to improve resistance to sulfur dioxide, the titanium oxide carrier may be further subjected to a calcination step before use. Through the step of calcining before use, the BET specific surface area of the titanium oxide carrier may be controlled so as to satisfy the following Relational Equation 1.

[Relational Expression 1]

0.1 ≤ BET ₁ /BET ₀ ≤ 0.5

(In Relation 1, BET ₀ is the initial BET specific surface area, and BET ₁ is the BET specific surface area after firing)

For example, BET ₁ /BET ₀ is preferably in the range of 0.2 to 0.45, or in the range of 0.3 to 0.4.

In addition, the step of preparing the slurry is not limited as long as it is a general dispersion condition selected from stirrer dispersion, homogenizer dispersion, ultra-high pressure dispersion and ultrasonic dispersion, and may preferably be a dispersion condition including ultrasonic dispersion.

For example, the calcining step is not limited as long as it is a normal condition, and may preferably be performed at 300 to 700° C., and more preferably at 300 to 500° C. In addition, the calcination may be performed for 1 hour to 24 hours.

Next, through the steps of drying and calcining the slurry, it is possible to prepare a catalyst in which an active metal is supported on a carrier. For example, the drying method is not particularly limited, and may be, for example, heating at 90 to 150° C. for 5 to 24 hours to remove the solvent. For example, the firing method is also not particularly limited, and for example, it may be a step of heating and firing in a closed heating space such as an oven. The firing may be performed, for example, in an air atmosphere, but is not limited thereto. For example, the sintering may be performed at a temperature of 300 to 700° C., and if the temperature range is satisfied, there is no stoichiometric disadvantage. In addition, the calcination is preferably performed for 1 hour to 24 hours.

In the method for preparing the first catalyst or the second catalyst according to an embodiment of the present invention, for example, the active metal of the second catalyst is gadolinium-vanadate, gadolinium:vanadium is 0.01:1 to 1:1 by weight. may be included as That is, the weight ratio of gadolinium to vanadium may be equal to or less than the equivalent level, and when such a weight ratio is satisfied, it is possible to give more advantages to the reduction of nitrogen oxides. However, it goes without saying that the gadolinium precursor and the vanadium precursor may be used under various conditions and compositions to satisfy the above-described gadolinium:vanadium weight ratio.

In addition, the first catalyst or the second catalyst described above may be a low-temperature SCR catalyst. In this case, the low-temperature SCR catalyst may exhibit high SCR performance even at low temperatures, but should not be interpreted as indicating SCR performance only at low temperatures. That is, stable SCR performance can be exhibited even during a normal high-temperature process.

As such, selective reduction may be performed through the first catalyst or the second catalyst. In a specific embodiment, selective reduction is possible at the low temperature, and the low temperature may satisfy 250° C. or less. Specifically, it may be in the range of 150 to 250 °C, more specifically 160 to 250 °C, and most specifically 180 to 250 °C.

In the case of the second catalyst, the conversion rate of nitrogen oxides according to the selective reduction may be 50% or more. As an example, the nitrogen oxide conversion according to the selective reduction may implement a nitrogen oxide conversion rate of 60% or more, or 70% or more, or 80% or more, or 90% or more at a temperature of 180°C.

As described above, it is possible to simultaneously reduce and remove carbon monoxide and nitrogen dioxide through the apparatus for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention, which can be applied to an internal combustion power generation system.

An internal combustion power generation system according to the present invention includes the device for simultaneously removing carbon monoxide and nitrogen oxides, and includes: an internal combustion engine in which fuel and air are introduced and combusted to drive a gas turbine; a power generation engine converting kinetic energy of the gas turbine into electrical energy; and the device through which the combustion gas discharged from the internal combustion engine flows into the first reaction unit.

The internal combustion power generation system according to the present invention may preferably be a liquefied natural gas power generation system. In liquefied natural gas power generation, at the beginning of operation, nitrogen dioxide (~70 ppm) and nitrogen monoxide (~80 ppm) are discharged together with a large amount of carbon monoxide (~2,000 ppm) due to incomplete combustion of the gas turbine, so the device according to the present invention When applied to liquefied natural gas power generation, it is environmentally and economically very advantageous by effectively removing carbon monoxide and nitrogen dioxide.

That is, the liquefied natural gas power generation system according to the present invention may include the internal combustion power generation system, the fuel is supplied from liquefied natural gas, and the combustion gas includes carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) It may be a complex harmful gas. Here, the fluid of the first reaction unit may be a complex harmful gas discharged from a liquefied natural gas power generation system.

In addition, the present invention provides a method for simultaneously removing carbon monoxide and nitrogen oxides, which has the same technical idea as the above-described apparatus.

The method for simultaneously removing carbon monoxide and nitrogen oxides according to the present invention is a first in which a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is converted into carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by a first catalyst A second reaction step and a fluid containing nitrogen monoxide (NO) that has passed through the first reaction step is converted into nitrogen (N ₂ ) and water (H ₂ O) by reacting with ammonia (NH ₃ ) by a second catalyst A reaction step, wherein the first catalyst is a carbon monoxide-nitrogen dioxide reduction catalyst including a support on which an active metal including a platinum group transition metal is supported, and the second catalyst is Gd, V, Mn, Co, Ni, La , Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and nitrogen oxide comprising a support on which an active metal containing any one or two or more selected from Lu It is a reduction catalyst, and the support of the first catalyst and the support of the second catalyst are each independently selected from aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, cerium oxide, silicon oxide, and carbon. do. As a specific example, the fluid of the first reaction step may be a complex harmful gas discharged from a liquefied natural gas power generation system.

As described above, in the apparatus and method for simultaneous removal of carbon monoxide and nitrogen oxides according to the present invention, in the first reaction step, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are removed in a specific temperature range, and carbon monoxide (CO) conversion rate and nitrogen dioxide (NO ₂ ) conversion rate is significantly high. As a preferred example, in the first reaction step, carbon monoxide (CO) conversion and nitrogen dioxide (NO ₂ ) conversion at 125° C. to 175° C. may all be 90% or more. Also as a preferred example, in the first reaction step, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) at 200° C. or less may be converted into carbon dioxide (CO ₂ ) or nitrogen monoxide (NO), and at 300° C. or less, carbon monoxide ( CO) can be converted to carbon dioxide (CO ₂ ).

As a preferred example, in the second reaction step, the nitrogen monoxide (NO) conversion at 200° C. or higher may be 90% or higher.

Also as a preferred example, the conversion temperature of the first reaction step and the second reaction step may be 100 to 400 ℃.

The internal combustion power generation method according to the present invention includes a method for simultaneously removing carbon monoxide and nitrogen oxides, comprising: a combustion step of burning fuel to drive a gas turbine; a power generation step of converting kinetic energy of the gas turbine into electrical energy; and a simultaneous removal step of removing carbon monoxide and nitrogen oxides by using the combustion gas generated by the combustion as the fluid of the first reaction step. In addition, the liquefied natural gas power generation method according to the present invention includes the internal combustion power generation method, wherein the fuel is supplied from liquefied natural gas, and the combustion gas is a complex harmful gas comprising carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) to be.

Hereinafter, the present invention will be described in detail by way of Examples, but these are for describing the present invention in more detail, and the scope of the present invention is not limited by the Examples below.

<Preparation of the first catalyst>

9.9 g of aluminum oxide (Al ₂ O ₃ ) powder having an average particle diameter of 170 μm as a support is added to 100 mL of distilled water in which 0.49 mmol of chloroplatinic acid (H ₂ PtCl ₆ ), an active metal precursor, is dissolved, ultrasonically dispersed for 30 minutes, and 2 hours while stirring to prepare a slurry.

Thereafter, the slurry was evaporated at 65°C using a rotary evaporator under conditions of 60°C and 65 mmHg, and then dried in a drying oven at 110°C for 24 hours to obtain a catalyst. The dried catalyst was heated to 400° C. at a temperature increase rate of 10° C./min, and calcined in an air atmosphere for 4 hours to prepare a platinum-supported aluminum oxide catalyst (Pt/Al ₂ O ₃ ).

The prepared catalyst was measured for carbon monoxide (CO) conversion and nitrogen dioxide (NO ₂ ) conversion through a fixed-bed continuous quartz tube test apparatus, and the results are shown in FIG. 3 .

In Example 1, a catalyst (Pt/TiO ₂ ) was prepared in the same manner as in Example 1, except that titanium oxide (TiO ₂ ) was used instead of aluminum oxide (Al ₂ O ₃ ) as a support. And the conversion rate and nitrogen dioxide (NO ₂ ) conversion of the catalyst were measured in the same manner as in Example 1, and the results are shown in FIG. 3 .

In Example 1, the same as in Example 1, except that a mixture (1:1 weight ratio) of aluminum oxide (Al ₂ O ₃ ) and titanium oxide (TiO ₂ ) was used instead of aluminum oxide (Al ₂ O ₃ ) as a support. A catalyst (Pt/Al ₂ O ₃ +TiO ₂ ) was prepared by the method. And the conversion rate and nitrogen dioxide (NO ₂ ) conversion of the catalyst were measured in the same manner as in Example 1, and the results are shown in FIG. 3 .

<Evaluation of the performance of the first catalyst>

The evaluation of the nitrogen oxide conversion rates of the second catalysts of Examples 1 to 3 was performed through a fixed-bed continuous quartz tube reactor. Specifically, the catalyst was used as a sample having a uniform size (diameter) of 300 to 425 μm using a 40-50 mesh sieving mesh. The flow rate was controlled using MFC (Mass Flow Controller, MKS Co.) from each cylinder with nitrogen, oxygen, carbon monoxide, and nitrogen dioxide supplied to the reactor. In addition, water supply was injected at a rate of 0.07cc/min using a solvent delivery pump. The flow rate of the reaction gas introduced into the reactor was 1,000 cc/min, and the concentration was set to 1,505 ppm CO, 100 ppm NO ₂ , 3.0 vol% O ₂ , 6.0 vol% H ₂ O, and the remaining amount of N ₂ . The catalyst charged in the reactor had a space velocity of 120,000 hr ^-1 and the corresponding catalyst volume was 0.5 cc.

In addition, analyzers and detection tubes were used to measure the concentrations of reactants and products. First, the carbon monoxide concentration was measured using a non-dispersive infrared gas analyzer (PG-250, HORIBA Co.) as a carbon monoxide measurement method. In order to remove moisture from the reaction gas before flowing into the analyzer, it was removed using a moisture trap in the cooling chiller. In the case of nitrogen dioxide, it was measured using a detection tube (9L, Gastec Co.) at the rear end of the reactor. After reaching a steady state at the reaction starting temperature of each reaction gas through the above method, the concentration change was measured at the rear end of the reactor by continuing until the concentration of the product became constant. All result data were measured after maintaining a steady state for 60 minutes at each reaction temperature. And the conversion rate of carbon monoxide (CO) was calculated using Equation 1 below, and the result is shown in FIG. 3 .

[Equation 1]

CO Conversion(%)={(C _CO,in -C _CO,out )/C _NO,in }×100

NO ₂ Conversion(%)={(C _NO2,in -C _NO2,out )/C _NO2,in }×100

(In Equation 2, C _CO,in is the CO concentration before the reaction, C _CO,out is the CO concentration after the reaction, C _NO2,in is the NO ₂ concentration before the reaction, C _NO2,out is the NO ₂ concentration after the reaction to be)

In Figure 3, Example 1 (Pt / Al ₂ O ₃ ) At 190 ° C. or more, the CO conversion rate is 90% or more, and at 180 ° C. or less, the NO ₂ conversion rate is 90% or more, CO and NO ₂ 90% conversion rate It can be seen that in order to simultaneously reduce the temperature, it is necessary to control the operation at each temperature. On the other hand, in Example 2 (Pt/TiO ₂ ), the CO conversion rate is 90% or more at 110 ° C. or more, and the NO ₂ conversion rate is 90% or more at 140 ° C. or less, and CO and NO ₂ in the temperature range of 110 to 140 ° C. 90 It can be seen that the % conversion can be simultaneously reduced. In particular, Example 3 (Pt/Al ₂ O ₃ +TiO ₂ ) has a CO conversion rate close to 100% at 120° C. or higher, and a NO ₂ conversion rate close to 100% at 180° C. or lower. It can be seen that a remarkable effect of reducing CO and NO ₂ at a 100% conversion rate at the same time in a wide temperature range is realized.

<Preparation of the second catalyst>

In 100 mL of distilled water in which 18 mmol of NH ₄ VO ₃ was dissolved, 0.64 mmol of Gd(NO ₃ ) ₃ .6H ₂ O was added to prepare a mixed solution, followed by stirring for 1 hour. At this time, when the NH ₄ VO ₃ was dissolved in distilled water, oxalic acid was mixed in a 1:1 molar ratio and used. After the stirring was completed, 9.0 g of anatase TiO ₂ powder (BET specific surface area 350 m ² /g) having an average particle diameter of 7.5 nm was added to the mixed solution, ultrasonically dispersed for 30 minutes, and stirred for 2 hours to prepare a slurry .

Thereafter, moisture was evaporated from the slurry using a rotary evaporator under conditions of 60° C. and 65 mmHg, and then dried in a drying oven at 120° C. for 24 hours to obtain a catalyst. The dried catalyst was heated to 400° C. at a temperature increase rate of 5° C./min, and calcined in an air atmosphere for 4 hours to prepare a catalyst (9V-0.5Gd/TiO ₂ ).

The prepared catalyst was specified by performing elemental analysis through inductively coupled plasma mass spectrometry (ICP-MS) analysis, and the results are shown in Table 1 below.

In Example 4, Gd(NO ₃ ) ₃ .6H ₂ O was used at 0.32 mmol, and TiO ₂ powder was used at 9.05 g, except for using the catalyst (9V-0.5Gd/TiO ₂ ) in the same manner as in Example 4 ) was prepared. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

In Example 4, Gd(NO ₃ ) ₃ .6H ₂ O was used at 1.91 mmol, and TiO ₂ powder was used at 8.80 g, except for using the catalyst (9V-3.0Gd/TiO ₂ ) in the same manner as in Example 4 ) was prepared. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

In Example 4, Gd(NO ₃ ) ₃ .6H ₂ O was used at 3.18 mmol, and TiO ₂ powder was used at 8.60 g, except that 8.60 g of the catalyst (9V-5.0Gd/TiO ₂ ) was used in the same manner as in Example 4 ) was prepared. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

In Example 4, Gd(NO ₃ ) ₃ .6H ₂ O was used at 6.37 mmol, and TiO ₂ powder was used at 8.10 g, except for using the catalyst (9V-10.0Gd/TiO ₂ ) in the same manner as in Example 4 ) was prepared. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

In Example 4, NH ₄ VO ₃ was used at 4 mmol, Gd(NO ₃ ) ₃ .6H ₂ O was used at 0.26 mmol, TiO ₂ powder was used at 3.76 g, and anatase (BET specific surface area 350 m) ² / g) _In the same manner as in Example ₄ , _the catalyst ( 5V-1.0Gd/TiO _2,400 ) was prepared. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

To 170 mL of distilled water in which 2.3 mmol of NH ₄ VO ₃ was dissolved, 1.15 mmol of Mn(NO ₃ ) ₂ .6H ₂ O of distilled water was added to prepare a mixed solution, followed by stirring for 1 hour. After the stirring was completed, 6 g of anatase TiO ₂ powder was added to the mixed solution, stirred for 24 hours, and then dehydrated. After dehydration, the obtained solid was calcined at 500° C. for 5 hours to prepare a catalyst. The prepared catalyst includes TiO ₂ having an anatase phase as a support, and MnV ₂ O ₆ as an active site in the support.

In Example 10, a catalyst containing CoV ₂ O ₆ as an active point was prepared by using Co(NO ₃ ) ₂ .H ₂ O as a cobalt salt instead of Mn(NO ₃ ) ₂ .6H ₂ O as a manganese salt. Except that, a catalyst was prepared in the same manner as in Example 10.

In Example 10, a catalyst containing NiV ₂ O ₆ as an active point was prepared by using Ni(NO ₃ ) ₂ .6H ₂ O as a nickel salt instead of Mn(NO ₃ ) ₂ .6H ₂ O as a manganese salt. Except that, a catalyst was prepared in the same manner as in Example 10.

[Comparative Example 1]

Commercial V/W/TiO ₂ catalyst (Ceram, Austria) was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

[Comparative Example 2]

In Example 4, Ni(NO ₃ ) ₂ .6H ₂ O 8.52 mmol was used instead of Gd(NO ₃ ) ₃ .6H ₂ O 0.64 mmol, and TiO ₂ powder was used at 8.60 g, except that 8.60 g was used. A catalyst (9V-5.0Ni/TiO ₂ ) was prepared in the same manner. And the catalyst was specified by performing elemental analysis through mass spectrometry (ICP-MS) analysis in the same manner as in Example 4, and the results are shown in Table 1 below.

V (wt%) W or Gd or Ni (wt%) Comparative Example 1 (commercial V/W/TiO ₂ catalyst) 5.8 W 4.0 Comparative Example 2 (9V-5.0Ni/TiO ₂ ) 8.5 Ni 5.3 Example 1 (9V-1.0Gd/TiO ₂ ) 8.9 Gd 1.3 Example 2 (9V-0.5Gd/TiO ₂ ) 8.7 Gd 0.6 Example 3 (9V-3.0Gd/TiO ₂ ) 9.1 Gd 3.7 Example 4 (9V-5.0Gd/TiO ₂ ) 9.1 Gd 5.8 Example 5 (9V-10Gd/TiO ₂ ) 8.9 Gd 11.3 Example 6 (5V-1.0Gd/TiO _2,400 ) 5.0 Gd 1.0

<Evaluation of the performance of the second catalyst>

1. NO _X conversion rate

The evaluation of the nitrogen oxide conversion rates of the second catalysts of Examples 4 to 12, Comparative Examples 1 and 2 was performed using a quartz fixed-bed vertical reactor having a diameter of 3/8 inch, and each catalyst was subjected to a hydraulic press. After pelletizing, it was used after sieving with 40-50 mesh. The reaction gas supplied to the reactor was adjusted to the flow rate of the total reaction gas to 1,000 sccm so that the space velocity (SV) of 60,000h ^-1 by adjusting the flow rate of each reaction gas using a MFC (Mass flow controller). The reaction gas has a composition ratio of NO 500 ppm, NH ₃ 500 ppm, O ₂ 3 vol%, H ₂ O 6 vol%, and N ₂ remaining amount.

In the evaluation of catalyst performance, the temperature of the reaction gas flowing into the reactor was kept constant at 180° C. in order to prevent salt formation and moisture condensation by NO and NH ₃ in the reaction gas.

Among the reactants and products, the NO _X concentration was measured with a non-dispersive infrared gas analyzer (NDIR), and the product passed through a cooling trap to completely remove moisture and then flowed into the gas analyzer. Among the reactants, NO ₂ and unreacted NH ₃ concentration were measured using a detection tube.

For evaluation of catalyst performance, after the temperature of the catalyst bed in the reactor reached 300°C, the reaction temperature was decreased at 20°C intervals while flowing the reaction gas to 160°C. In addition, it was measured after maintaining the concentration of the product at each reaction temperature until it was constant, and the NO _X conversion rate was calculated through Equation 2 below.

[Equation 2]

NO _X Conversion(%)={(C _NO,in -C _NO,out )/C _NO,in }×100

(In Equation 2, C _NO,in is the NO concentration before the reaction, and C _NO,out is the NO concentration after the reaction)

2. Durability and performance evaluation

The catalytic performance and durability of the second catalysts of Examples 4 to 9, Comparative Examples 1 and 2 were evaluated by the following evaluation method.

Evaluation conditions 1) NO _X =500ppm, NH ₃ =500ppm, 3vol% O ₂ , 6vol% H ₂ O, space velocity 60,000 hr ^-1

Evaluation condition 2) Step by step evaluation while sequentially flowing or stopping the reaction gas in which SO ₂ =100 ppm exists in the condition of evaluation condition 1) (6 vol% H ₂ O and 100 ppm SO ₂ conditions -> 6vol% H ₂ O conditions -> dry conditions -> dry and 100 ppm SO ₂ conditions).

Evaluation condition 3) T=180℃, NO/NH ₃ = 1:1 (500ppm), 3vol% O ₂ , 6vol% H ₂ O and space velocity 60,000h ^-1

Evaluation condition 4) Repeated temperature change of 300℃ -> 140℃ -> 300℃ -> 140℃

In addition, the results are shown in Figs. 4 to 8 below.

As shown in FIG. 4 , it was confirmed that the nitrogen oxide reduction catalyst according to the present invention can realize a nitrogen oxide conversion rate of 98% or more even at a low temperature of 240° C. or less. Specifically, it was confirmed that all of Examples 4 to 9 implement a nitrogen oxide conversion rate of 50% or more at a temperature of 160°C or higher, and a nitrogen oxide conversion rate of 90% or more at a temperature near 200°C or higher. In addition, as a result of comparing the nitrogen oxide conversion rate at 180° C., Example 4 was confirmed to have an effect of more than 180 times improved compared to Comparative Example 1. In addition, when the V:Gd weight ratio is 9:1 (Example 4), the highest nitrogen oxide conversion rate is shown, and when the V:Gd weight ratio is 1:1 or more (Example 8), the nitrogen oxide conversion rate tends to be slightly lowered showed In addition, in the case of Comparative Example 2, in which nickel as a transition metal was used instead of gadolinium, a nitrogen oxide conversion rate at a significantly lower level than that of Comparative Example 1, a commercial catalyst, was shown.

In addition, the catalysts of Examples 10 to 12 were confirmed to have an effect of removing nitrogen oxides although the temperature was higher than that of the catalysts of Examples 4 to 9.

According to the results in the evaluation condition 1) for confirming the effect of improving the resistance to moisture, as shown in FIG. 5, in the case of Example 4, the performance degradation rate under the moisture condition compared to the nitrogen oxide conversion rate under the water-free condition was It was confirmed that the resistance to moisture was significantly improved as compared to Comparative Example 1 by about 8.2%. In addition, it was confirmed that the durability was excellent due to the resistance to SO ₂ as high as about 8% of the performance degradation rate even in the presence of 100 ppm of sulfur dioxide (SO ₂ ) in addition to moisture. On the other hand, in the case of Comparative Example 1, the resistance to moisture and SO ₂ was significantly lower than in Examples.

In addition, as a result of exposing each catalyst to evaluation condition 2), as shown in FIG. 6 , in the case of Example 4, it was confirmed that the conversion rate of nitrogen oxides, that is, excellent denitration efficiency, could be exhibited with a significant difference compared to Comparative Example 1. did.

In addition, as a result of exposing the catalyst to the evaluation condition 3), as shown in FIG. 7 , in the case of Example 4, it was confirmed that the denitration efficiency of 92% was maintained for 13 hours without degradation in the moisture condition.

In addition, as a result of exposing the catalyst to evaluation condition 4), as shown in FIG. 8, in the case of Example 4, it was confirmed that the denitration efficiency close to 100% was maintained for 13 hours even with repeated temperature changes.

In addition, when V:Gd was supported in a 5:1 weight ratio on a titanium oxide support whose BET specific surface area was controlled to be about 140 m ² /g by firing (Example 9), the resistance to moisture was obtained in Example 4 Although it appears large compared to that of SO ₂ at the same concentration (100 ppm), the performance degradation rate in the presence of about 2.8% was confirmed to have a very high SO ₂ resistance compared to Example 4.

From these results, the second catalyst according to the present invention is very suitable for a system for simultaneously removing carbon monoxide and nitrogen oxides in which the first reaction and the second reaction are sequentially performed with excellent conversion rate and durability of nitrogen oxide, of which V: Gd It was confirmed that, when supported in this 9:1 weight ratio (Example 4), the maximum effect could be exhibited.

Claims (19)

A first reaction unit in which a fluid containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is introduced, and converted into carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by a first catalyst; and
Ammonia (NH ₃ ) is introduced, a fluid containing nitrogen monoxide (NO) is introduced from the first reaction unit, and the nitrogen monoxide (NO) is reacted with the ammonia (NH ₃ ) by a second catalyst to nitrogen (N ₂ ) and a second reaction unit converted to water (H ₂ O);
The first catalyst is a carbon monoxide-nitrogen dioxide reduction catalyst including a support on which an active metal including a platinum group transition metal is supported,
The second catalyst is any one selected from Gd, V, Mn, Co, Ni, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, or It is a nitrogen oxide reduction catalyst comprising a support on which an active metal containing two or more is supported,
The support of the first catalyst and the support of the second catalyst are each independently selected from aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, cerium oxide, silicon oxide, and carbon monoxide comprising at least one or two or more of carbon and nitrogen. Simultaneous removal of oxides. ◈Claim 2 was abandoned when paying the registration fee.◈ According to claim 1,
In the first catalyst, the platinum group transition metal of the active metal includes Pt, and the support is a device for simultaneously removing carbon monoxide and nitrogen oxides including aluminum oxide and titanium oxide. ◈Claim 3 was abandoned when paying the registration fee.◈ According to claim 1,
In the second catalyst, the active metal includes Gd and V, and the support is a device for simultaneously removing carbon monoxide and nitrogen oxides including titanium oxide. ◈Claim 4 was abandoned when paying the registration fee.◈ According to claim 1,
The support of the first catalyst or the support of the second catalyst has a BET specific surface area of 100 m ² /g or more. According to claim 1,
The fluid of the first reaction unit is a simultaneous removal device of carbon monoxide and nitrogen oxides, which are complex harmful gases discharged from the liquefied natural gas power generation system. An internal combustion power generation system comprising the device for simultaneously removing carbon monoxide and nitrogen oxides according to any one of claims 1 to 5,
an internal combustion engine in which fuel and air are introduced and combusted to drive a gas turbine;
a power generation engine converting kinetic energy of the gas turbine into electrical energy; and
and the device through which the combustion gas discharged from the internal combustion engine flows into the first reaction unit. A liquefied natural gas power generation system comprising the internal combustion power generation system of claim 6,
The fuel is supplied from liquefied natural gas,
The combustion gas is a liquefied natural gas power generation system that is a complex harmful gas containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ). a first reaction step in which a fluid comprising carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) is converted to carbon dioxide (CO ₂ ) and nitrogen monoxide (NO) by a first catalyst; and
A second reaction step in which the fluid containing nitrogen monoxide (NO) that has passed through the first reaction step is converted to nitrogen (N ₂ ) and water (H ₂ O) by reacting with ammonia (NH ₃ ) by a second catalyst includes,
The first catalyst is a carbon monoxide-nitrogen dioxide reduction catalyst including a support on which an active metal including a platinum group transition metal is supported,
The second catalyst is any one selected from Gd, V, Mn, Co, Ni, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, or It is a nitrogen oxide reduction catalyst comprising a support on which an active metal containing two or more is supported,
The support of the first catalyst and the support of the second catalyst are each independently selected from aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, cerium oxide, silicon oxide, and carbon monoxide comprising at least one or two or more of carbon and nitrogen. Simultaneous removal of oxides. ◈Claim 9 was abandoned at the time of payment of the registration fee.◈ 9. The method of claim 8,
In the first catalyst, the platinum group transition metal of the active metal includes Pt, and the support includes aluminum oxide and titanium oxide. 10. The method of claim 9,
In the first reaction step, carbon monoxide (CO) conversion and nitrogen dioxide (NO ₂ ) conversion at 125° C. to 175° C. are both 90% or more. A method of simultaneously removing carbon monoxide and nitrogen oxides. ◈Claim 11 was abandoned when paying the registration fee.◈ 10. The method of claim 9,
In the first reaction step,
At 200 ° C. or less, carbon monoxide (CO) and nitrogen dioxide (NO ₂ ) are converted into carbon dioxide (CO ₂ ) or nitrogen monoxide (NO),
Simultaneous removal of carbon monoxide and nitrogen oxides in which carbon monoxide (CO) is converted to carbon dioxide (CO ₂ ) at 300° C. or less. ◈Claim 12 was abandoned when paying the registration fee.◈ 9. The method of claim 8,
In the second catalyst, the active metal includes gadolinium and vanadium, and the support is a method of simultaneously removing carbon monoxide and nitrogen oxides including titanium oxide. 13. The method of claim 12,
In the second reaction step, the nitrogen monoxide (NO) conversion rate at 200 ° C. or higher is a method of simultaneously removing carbon monoxide and nitrogen oxides of 90% or more. ◈Claim 14 was abandoned when paying the registration fee.◈ 9. The method of claim 8,
The conversion temperature of the first reaction step and the second reaction step is 100 to 400 ℃ Simultaneous removal of carbon monoxide and nitrogen oxides. ◈Claim 15 was abandoned when paying the registration fee.◈ 9. The method of claim 8,
The first catalyst or the second catalyst,
preparing a slurry by adding a support to an aqueous active metal precursor solution; and
Simultaneous removal of carbon monoxide and nitrogen oxides prepared including the step of calcining the slurry to obtain a catalyst comprising a support on which an active metal is supported. ◈Claim 16 has been abandoned at the time of payment of the registration fee.◈ 16. The method of claim 15,
The method for simultaneously removing carbon monoxide and nitrogen oxides, wherein the support of the first catalyst or the support of the second catalyst has a BET specific surface area of 100 m ² /g or more. 9. The method of claim 8,
The fluid of the first reaction step is a method of simultaneously removing carbon monoxide and nitrogen oxides, which are complex harmful gases discharged from a liquefied natural gas power generation system. An internal combustion power generation method comprising the method for simultaneously removing carbon monoxide and nitrogen oxides of claim 17,
a combustion step of burning fuel to drive a gas turbine;
a power generation step of converting kinetic energy of the gas turbine into electrical energy; and
and a simultaneous removal step of removing carbon monoxide and nitrogen oxides by using the combustion gas generated by the combustion as the fluid of the first reaction step. A liquefied natural gas power generation method comprising the internal combustion power generation method of claim 18,
The fuel is supplied from liquefied natural gas,
The combustion gas is a liquefied natural gas power generation method that is a complex harmful gas containing carbon monoxide (CO) and nitrogen dioxide (NO ₂ ).

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