KR20130143146A - Flow-through metal fiber substrate structure for catalyst coating to purify the harmful emission gas and purification apparatus having the same - Google Patents

Abstract

The present invention relates to an air-permeable metal fiber media for catalyst coating for purifying emission gas comprising a first media member having a plurality of openings for the permeation of harmful emission gas formed, and arranged in a lengthwise direction; and a second media member stacked on the top or bottom of the first media member and composed of a porous material to corrugate. The first media member and the second media member are arranged on top of each other and wound to form a spiral. Accordingly the performance of purification is relatively increased by increasing a contact area between the harmful emission gas and the media while preventing the increase of back pressure.

Description

GLOW-THROUGH METAL FIBER SUBSTRATE STRUCTURE FOR CATALYST COATING TO PURIFY THE HARMFUL EMISSION GAS AND PURIFICATION APPARATUS HAVING THE SAME}

The present invention relates to a gas-permeable metal fiber carrier for catalyst coating for the purification of harmful exhaust gases, and more particularly, is provided to allow the harmful exhaust gas to be purified to flow to various parts between the carrier structures. The present invention relates to a gas-permeable metal fiber carrier for coating a catalyst for the purification of harmful exhaust gases, which can prevent the back pressure rise and minimize the volume while increasing the purification efficiency according to the increase of the contact area.

Exhaust from vehicles is composed of particulate matter (PM), hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx), etc. in addition to water and carbon dioxide. It narrows and causes lung diseases.

Devices such as Diesel Oxidation Catalyst (DOC), Selective Catalytic Reduction (SCR), Three Way Catalyst (TWC) or Diesel Particulate Filter (DPF) are used to treat these harmful exhausts. Carriers are employed.

Here, it is preferable that the carrier is designed so that the contact area with the noxious exhaust gas is widened in order to ensure the highest purification (lower) efficiency as possible.

However, in order to secure high purification efficiency of the exhaust gas, it is preferable that the contact area be widened. However, the back pressure may increase due to an increase in the substrate volume and an increase in the cell density.

Gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to the present invention is derived to solve the above-mentioned problems, and aims to solve the following problems.

In one aspect, an object of the present invention is to provide a gas-permeable metal fiber carrier for coating a catalyst for the purification of harmful emissions, which can increase the contact area of the harmful emissions and the carrier while preventing back pressure rise.

In addition, an aspect of the present invention is to provide a gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions, which may increase the purification efficiency with increasing contact area.

In addition, an object of the present invention is to provide a gas-permeable metal fiber carrier for coating a catalyst for the purification of harmful emissions, in which the amount of catalyst added to the carrier can be relatively reduced by increasing the contact area.

The solution to the problem of the present invention is not limited to those mentioned above, and other solutions not mentioned can be clearly understood by those skilled in the art from the following description.

Gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention is formed with a plurality of openings through which the harmful emissions can pass, the first carrier member and the longitudinally arranged It is laminated on the upper side or the lower side of the first carrier member, and includes a second carrier member that is porous and formed irregularities, wherein the first carrier member and the second carrier member are provided to be wound in a stacked state to form a spiral shape do.

The first carrier member or the second carrier member may be a wire mesh or a metal fiber in a gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention. It can be formed into).

In addition, the unevenness of the second carrier member in the gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention may be formed in a wavy pattern.

In addition, the gas-permeable metal fiber carrier for catalyst coating for purifying harmful exhaust gas according to an embodiment of the present invention may be formed larger than the opening of the second carrier member having a porous size of the first carrier member. have.

In addition, the gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention may be wound while the second carrier member is stacked on the first carrier member to form a cylindrical shape. have.

In addition, the harmful exhaust gas introduced through the cylindrical side surface of the gas-permeable metal fiber carrier for catalyst coating for purifying the harmful exhaust gas according to an embodiment of the present invention is porous with the first carrier member having a plurality of openings. It may be provided to flow between the second carrier member.

In addition, a catalyst may be added to at least one of the first carrier member and the second carrier member in the gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention.

In addition, the catalyst in the gas permeable metal fiber carrier for catalyst coating for the purification of harmful emissions according to an embodiment of the present invention is platinum (Pt, platinum), palladium (Pd, Palladium), rhodium (Rh, rhodium), Alumina (Al 2 O 3, Alumina) zeolite (zeolite) or vanadium (V, vanadium) may be provided including one or more.

On the other hand, the harmful exhaust gas purification apparatus, such as an internal combustion engine having a gas permeable metal fiber carrier for the catalyst coating for the purification of harmful exhaust gas according to an embodiment of the present invention purification of harmful emissions according to an embodiment of the present invention A gas permeable metal fiber carrier for the catalyst coating and an inlet and an outlet are formed for the catalyst coating, and an exhaust part for accommodating the gas permeable metal fiber carrier for the catalyst coating for purification of the harmful exhaust gas.

Gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention has at least some of the following effects.

Gas permeable metal fiber carrier for catalyst coating for the purification of harmful emissions according to an embodiment of the present invention can minimize the carrier volume by providing a contact area between the harmful emissions and the carrier while preventing back pressure rise. It has an effect.

In addition, the gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention has an effect of relatively increasing the purification efficiency as the contact area of the hazardous emissions and the carrier increases.

In addition, the gas-permeable metal fiber carrier for catalyst coating for purifying harmful exhaust gas according to an embodiment of the present invention has an effect of relatively reducing the amount of catalyst added to the carrier by increasing the contact area and the initial purification efficiency. have.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is a perspective view of a gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention.
2 (a) and 2 (b) is a state in which the first carrier member and the second carrier member of the gas permeable metal fiber carrier for the catalyst coating for purification of harmful emissions according to an embodiment of the present invention is disposed Figure is shown.
3 is a view illustrating a process of flowing harmful emissions through the gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention.
4 is a view illustrating a temperature distribution result according to a flow of a harmful exhaust gas in a conventional gas-transparent metal fiber carrier for catalyst coating and a conventional carrier for purification of harmful emissions according to an embodiment of the present invention.
5 is a view showing a harmful exhaust gas purification apparatus having a gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention.
Figure 6 (a) to Figure 6 (c) shows the weight per unit area of the metal fiber in the second carrier member of the gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions according to an embodiment of the present invention Drawing.

As used herein, the singular forms "a", "an," "an," "include," "include," and the like are to be construed as including plural referents unless the context clearly dictates otherwise. Means the presence of, or a combination of, one or more other features, numbers, steps, operations, components, parts, or combinations thereof, And the like.

Hereinafter, with reference to the drawings will be described in detail with respect to the gas-permeable metal fiber carrier 100 for the catalyst coating for the purification of harmful emissions, and the harmful emission gas purification apparatus 300 having the same.

1 and 2, the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention and the harmful emission gas purification apparatus 300 including the hazardous emission A plurality of openings 111 through which gas can pass are formed, and include a first carrier member 110 arranged in the longitudinal direction.

In addition, the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention and the harmful emission gas purification apparatus 300 having the same are provided in the first carrier member 110. The second carrier member 120 is stacked on the upper side or the lower side and provided as the porous 121 to form the unevenness 122.

In addition, the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention and the hazardous emission gas purification apparatus 300 including the first carrier member and the second carrier are provided. The carrier members are wound in a stacked state to form a spiral shape.

On the other hand, the gas permeable metal fiber carrier for catalyst coating 100 and the harmful exhaust gas purification apparatus 300 having the same for the purification of harmful emissions according to an embodiment of the present invention is a variety of devices that emit harmful emissions, That is, it can be used for the purification device of harmful exhaust gas generated and emitted from various internal combustion engines, etc., and applied to diesel engines or gasoline engines of vehicles, construction machines, generators, ships, trains, motorcycles, etc., to which the internal combustion engines are used. Can be.

In addition, the longitudinal direction used in the specification of the present invention is harmful in the gas permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions based on the XY plane, and the harmful emission gas purification apparatus 300 having the same. The direction perpendicular to the direction in which the exhaust gas is transmitted.

Hereinafter, each configuration will be described in detail.

Referring to FIG. 2, the first carrier member 110 is provided with a plurality of openings 111 through which noxious exhaust gas can pass, and is arranged in the longitudinal direction.

Here, the first carrier member 110 may be formed of a wire mesh or a metal fiber.

Referring to FIG. 2, the second carrier member 120 is stacked on the upper side or the lower side of the first carrier member 110, is provided with a porous 121, and the unevenness 122 is formed, and the first carrier member ( In a state of being laminated on 110, it is provided to be wound from one side.

That is, in a state where the first carrier member 110 and the second carrier member 120 are arranged as shown in FIG. 2, the first carrier member 110 and the second carrier member 120 When the first carrier member 110 and the second carrier member 120 are wound from one side in a state in which the first carrier member 110 and the second carrier member 120 are in contact with each other, the first carrier member 110 as shown in FIG. And a gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful exhaust gas wound in a spiral manner in which the second carrier member 120 is spirally formed.

In addition, the first carrier member 110 and the second carrier member 120 are provided to support the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention. The support 130 may be installed on the outer portion wound in a spiral shape.

In addition, the support 130 may have a circular cross section and may be formed of a metal material.

Here, when the second carrier member 120 is stacked on the first carrier member 110, the second carrier member 120 is formed with an unevenness 122, so that the second carrier member ( A space may be formed between the uneven portion 122 of the 120 and the first carrier member 110.

Then, the harmful exhaust gas to be purified is provided to be flowable through the space formed between the uneven 122 and the first carrier member 110 of the second carrier member 120 (see Fig. 3).

In addition, the second carrier member 120 may be provided in a porous structure 121 to allow harmful emissions to pass therethrough. Through this, as described below, the harmful exhaust gas to be purified may flow between the second carrier member 120 and the first carrier member 110.

Here, the second carrier member 120 may be formed of a wire mesh or a metal fiber. Preferably, in the case of the first carrier member 110, a wire mesh is formed. ), And the second carrier member 120 may be formed of metal fiber.

On the other hand, the second carrier member 120 is formed with an unevenness 122, as shown in Figure 2, the unevenness 122 of the second carrier member 120 may be formed in a wavy pattern. .

The opening 111 of the first carrier member 110 may have a larger size than the hole of the second carrier member 120 formed of the porous body 121.

Referring to FIG. 2, the first carrier member 110 is disposed in the longitudinal direction, and the second carrier member 120 is stacked above or below the first carrier member 110.

Here, when the second carrier member 120 is rotated from one side in a state in which the second carrier member is stacked on the first carrier member 110, as shown in FIG. The flowable metal fiber carrier 100 may be formed.

Referring to FIG. 3, the harmful exhaust gas flowing through the cylindrical side surface flows between the first carrier member 110 having the plurality of openings 111 and the second carrier member 120 of the porous 121. It may be arranged to.

Here, as shown in Figure 3, the harmful exhaust gas flowing through the uneven 122 of the second carrier member 120 of the cylindrical side is filtered while contacting the second carrier member 120, the first 2 may move upwards or downwards through the opening 111 of the first carrier member 110 in contact with the carrier member 120 (see arrow 3 in FIG. 3), and the harmful exhaust gas may have unevenness 122 formed therein. The second carrier member 120 may be in contact with the other carrier member 120.

That is, the gas-permeable metal fiber carrier 100 for catalyst coating for purifying harmful exhaust gas according to an embodiment of the present invention has a property of flowing through a wall, and thus the contact area may be increased.

In the case of the conventional carrier (P), the opening corresponding to the first carrier member 110 of the gas permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention is an opening 111. ) Is provided as a flat member that is not formed, since the harmful exhaust gas to be purified does not pass through the flat member and flows only in a straight direction through the unevenness of the uneven member corresponding to the second carrier member 120. The contact area became narrow.

In order to solve the problem of narrowing the contact area, when the pores of the porous 121 of the uneven member are narrowed, the cell density increases and the back pressure due to the exhaust resistance increases.

However, since the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention has a plurality of openings 111 formed in the first carrier member 110, purification The target harmful emissions include a plurality of openings 111 formed in the first carrier member 110 as well as a linear movement in the direction in which the hazardous emissions are moved through the unevenness 122 formed in the second carrier member 120. ) Can move upward or downward, ie flow through the wall.

As a result, the second carrier member 120 of the first introduced portion as well as the second carrier member 120 formed on the upper side and the lower side can be contacted, so that a reaction in which the harmful exhaust gas contacts the carrier is relatively higher than that of the conventional carrier. Will increase.

In other words, the first carrier member 110 and the second carrier member 120 is laminated harmfully introduced through the side of the gas permeable metal fiber carrier 100 for the catalyst coating for purification of the harmful exhaust gas is rolled back The exhaust gas flows through the wall while passing through the upper and lower sides as well as the uneven portion 122 of the second carrier member 120 first introduced into the second carrier member 120, thereby allowing contact with various parts of the second carrier member 120.

From this, since the contact area can be sufficiently increased without increasing the holes formed by the second carrier member 120 and the first carrier member 110, the harmful exhaust gas and the carrier can be prevented while increasing the back pressure. The effect of relatively increasing the purification efficiency by increasing the contact area of can be recognized.

4 is harmful from the gas-permeable metal fiber carrier 100 (see FIG. 4 (a)) and the conventional carrier (see FIG. 4 (b)) for catalyst coating for purification of harmful emissions according to an embodiment of the present invention. A diagram illustrating a temperature distribution result according to exhaust gas flow.

That is, after introducing the harmful exhaust gas heated to 400 ℃ through one side of the center of the carrier, the temperature distribution of the entire carrier imaged by the thermal imaging camera on the opposite side is shown.

Referring to FIG. 4, in the case of the gas-permeable metal fiber carrier 100 (see FIG. 4 (a)) for catalyst coating for purification of harmful emissions according to an embodiment of the present invention, the harmful substances heated in the center of the carrier Even when the exhaust gas is injected, the heated harmful exhaust gas moves between the first carrier member 110 and the second carrier member 120 to flow evenly with respect to the entire carrier, so that the temperature is evenly distributed throughout the carrier cross section. Show results.

However, as described above, in the case of the conventional carrier P having a configuration corresponding to the first carrier member 110 as a flat member having no opening 111 formed therein, the harmful exhaust gas heated at the center of the carrier is applied. When spraying, the heated harmful exhaust gas moves only through the passage formed in the center of the carrier, so that the center of the carrier has a relatively high temperature distribution, whereas the outside of the carrier has a relatively low temperature distribution (see FIG. 4 (b)). .

That is, as a result of the experiment of FIG. 4, since the gas-permeable metal fiber carrier for catalyst coating 100 for purifying harmful emissions according to an embodiment of the present invention flows harmful substances into various parts of the upper side or the lower side, It can be seen that the area in which the harmful exhaust gas contacts the carrier is relatively increased compared to the carrier of.

Meanwhile, a catalyst may be added to at least one of the first carrier member 110 or the second carrier member 120.

That is, at least one of the first carrier member 110 or the second carrier member 120 is coated with a catalyst and thus discharges harmful substances passing through the first carrier member 110 or the second carrier member 120. It may be provided to oxidize and reduce harmful carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx) and the like into carbon dioxide (CO2), water (H2O), nitrogen (N2), and the like, which are harmless to the human body.

Here, in order to actively contact the harmful exhaust gas with the catalyst, a method of increasing the surface area of the first carrier member 110 or the second carrier member 120 coated with the catalyst may be considered.

That is, when the surface area of the first carrier member 110 or the second carrier member 120 is increased, the coating area of the catalyst is correspondingly increased, and the contact area of the hazardous emission gas is also increased, so that the harmful emission gas purification rate is increased. Can be increased.

In the case of the second carrier member 120 in the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention, a metal fiber may be disposed on one side of a mesh. As shown in FIG. 6, the surface area may be adjusted by adjusting the amount of metal fibers disposed on the mesh.

)인 경우, 제2담체부재(120)는 대략 174(

)의 평균공극크기(Mean Pore Size)를 가지게 되고, 도 6(b)에서와 같이, 단위 면적당 중량이 250(

)인 경우, 제2담체부재(120)는 대략 151(

)의 평균공극크기를 가지며, 도 6(c)에서와 같이, 단위 면적당 중량이 350(

)인 경우, 제2담체부재(120)는 대략 136(

)의 평균공극크기를 가진다.That is, as shown in Fig. 6 (a), the weight per unit area is 150 (

), The second carrier member 120 is approximately 174 (

It has an average pore size of), and as shown in Figure 6 (b), the weight per unit area is 250 (

), The second carrier member 120 is approximately 151 (

It has an average pore size of), as shown in Figure 6 (c), the weight per unit area is 350 (

), The second carrier member 120 is approximately 136 (

Average pore size

Here, since the average pore size decreases as the weight of the metal fiber per unit area increases, the area where the harmful exhaust gas contacts the metal fiber increases.

In addition, since the average pore size increases as the weight of the metal fiber per unit area decreases, the area where the harmful exhaust gas contacts the metal fiber decreases.

That is, it is possible to control the degree of purification of harmful emissions through the control of the metal fiber weight or the layer of the metal fiber.

The catalyst may include one or more of platinum (Pt, platinum), palladium (Pd, Palladium), rhodium (Rh, rhodium), alumina (Al2O3, Alumina) zeolite or vanadium (V, vanadium). Can be.

In addition, the gas-permeable metal fiber carrier for catalyst coating for purifying harmful exhaust gas according to an embodiment of the present invention has an amount of catalyst added to the carrier because the area in which the hazardous exhaust gas contacts the carrier is relatively increased. This has a relatively reduced effect.

On the other hand, gas permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions according to an embodiment of the present invention and the harmful emission gas purification apparatus 300 having the same is DOC ( Diesel Oxidation Catalyst (SCR), Selective catalytic reduction (SCR), Three Way Catalyst (TWC) or Diesel Particulate Filter (DPF).

In particular, in the case of TWC (Three Way Catalyst), it is possible to reduce carbon monoxide (CO), hydrocarbon (HC), nitrogen oxides (NOx) by the catalytic reaction, and in the case of SCR (Selective catalytic reduction), NOx) can be reduced.

Hereinafter, the operation and effects of the embodiment of the harmful exhaust gas purification apparatus 300 having the gas-permeable metal fiber carrier 100 for catalyst coating for purification of the harmful exhaust gas according to an embodiment of the present invention will be described.

First, referring to FIG. 5, in the harmful exhaust gas purification apparatus 300 including the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful exhaust gas according to an embodiment of the present invention, various vehicles are provided. Exhaust unit 200, etc. is connected to the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful exhaust gas according to an embodiment of the present invention, harmful emissions discharged through the exhaust unit 200 Gas is introduced into the gas-permeable metal fiber carrier 100 for catalyst coating for purification of the harmful exhaust gas.

Next, the gas-permeable metal fiber carrier for catalyst coating 100 for purifying the harmful exhaust gas has a first carrier member 110 having a plurality of openings 111 formed in a lengthwise direction, and provided with a porous body 121. The second carrier member 120 having the unevenness 122 formed thereon is stacked above or below the first carrier member 110, and the first carrier member 110 and the second carrier member 120 are stacked. In this state, it may be wound from one side to form a gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful exhaust gas in a cylindrical shape.

Next, the harmful exhaust gas flowing through the cylindrical side surface flows between the first carrier member 110 having the plurality of openings 111 and the second carrier member 120 of the porous 121, and thus harmful emissions. The gas comes into contact with various parts of the gas-permeable metal fiber carrier 100 for catalyst coating for purification of harmful emissions, thereby increasing the contact area between the harmful emissions and the carrier while preventing back pressure rise.

In addition, the noxious exhaust gas purifying apparatus 300 including the gas-permeable metal fiber carrier 100 for catalyst coating for the noxious exhaust gas purification according to an embodiment of the present invention increases the contact area of the noxious exhaust gas and the carrier. It can increase the efficiency of harmful emissions purification.

It is to be understood that within the scope of the technical idea included in the specification and drawings of the present invention, the description of the present invention, the present embodiment, and the drawings attached hereto are only a part of the technical idea included in the present invention, The present invention is not limited to the above-described embodiments, and various modifications and changes may be made without departing from the scope of the present invention.

100: gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions
110: first carrier member 111: opening
120: second carrier member 121: porous
122: unevenness 130: support portion
200:
300: Purifying device having a gas-permeable metal fiber carrier for catalyst coating for purification of harmful emissions

Claims (9)

A first carrier member having a plurality of openings through which harmful exhaust gas can pass, and arranged in a longitudinal direction; And
And a second carrier member stacked on an upper side or a lower side of the first carrier member and provided in a porous manner to form irregularities.
And the first carrier member and the second carrier member are wound in a stacked state to form a spiral shape. The method of claim 1,
The first carrier member or the second carrier member is a gas-permeable metal fiber carrier for coating the catalyst for the purification of harmful emissions, characterized in that formed of a wire mesh (Wire Mesh) or metal fiber (Metal Fiber). The method of claim 1,
The gas-permeable metal fiber carrier for catalyst coating for purification of harmful exhaust gases, characterized in that the irregularities of the second carrier member are formed in a wavy pattern. The method of claim 1,
The gas permeable metal fiber carrier for catalyst coating for the purification of harmful exhaust gases, characterized in that the opening size of the first carrier member is formed larger than the hole of the second carrier member formed porous. The method of claim 1,
The gas-permeable metal fiber carrier for coating a catalyst for the purification of noxious exhaust gases, characterized in that the second carrier member is wound in a state of being laminated on the first carrier member to form a cylindrical shape. The method of claim 5,
The harmful exhaust gas introduced through the cylindrical side surface is provided to flow between the first carrier member having a plurality of openings and the porous second carrier member. Ryu metal fiber carrier. The method of claim 1,
At least one of the first carrier member or the second carrier member is a gas permeable metal fiber carrier for coating the catalyst for the purification of harmful emissions, characterized in that the catalyst is added. The method of claim 7, wherein
The catalyst may include one or more of platinum (Pt, platinum), palladium (Pd, Palladium), rhodium (Rh, rhodium), alumina (Al2O3, Alumina) zeolite or vanadium (V, vanadium). Gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions. A gas permeable metal fiber carrier for catalyst coating for purifying the noxious exhaust gas according to any one of claims 1 to 8; And
An inlet and an outlet are formed, and an exhaust part for receiving a gas-permeable metal fiber carrier for catalyst coating for the purification of the harmful exhaust gas;
Purification device comprising a gas permeable metal fiber carrier for catalyst coating for purification of harmful emissions comprising a.

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