JP2005342606A - Filter, and apparatus and method for purifying exhaust gas from internal-combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a filter the volume of which is not decreased or the exhaust gas flow passage (cell) of which is not clogged due to the ash to be generated by burning a particulate matter in exhaust gas accumulated in the filter and consequently the pressure loss of which is not increased and a catalyst-coated layer is not deactivated. <P>SOLUTION: This filter is used for purifying the particulate matter-containing exhaust gas discharged from an internal-combustion engine. A particle of an ash capturing material is dispersed/incorporated in the catalyst-coated layer formed on the surface of an internal partition wall of a cell of this filter or on the surface of a ceramic particle forming the internal partition wall. In each of this apparatus and this method for purifying exhaust gas from the internal-combustion engine, this filter is used. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a filter for removing and purifying harmful components such as carbon monoxide and nitride oxide, or particulate matter in exhaust gas discharged from an internal combustion engine such as a gasoline engine or a diesel engine, and its The present invention relates to an exhaust gas purification apparatus using a filter and an exhaust gas purification method performed using this apparatus, and in particular, ash contained in the particulate matter is confined in a specific location in the filter and does not cause pressure loss. A filter that can be removed is proposed.

  In recent years, internal combustion engines mounted on automobiles, construction machines, etc. have been purifying exhaust gas by purifying harmful gas components such as nitrogen oxides (NOx) and hydrocarbons (HC) contained in the exhaust gas. It is normal. For diesel engines, in addition to nitrogen oxides (NOx) and hydrocarbons (HC), so-called particulate matter (PM) such as TDI (soot) and SOF (Soluble Organic Fraction) is reduced. It is necessary.

  Under such circumstances, various exhaust gas purifying apparatuses for internal combustion engines have been proposed. For example, as an example of such an exhaust gas purification device, there is one in which a particulate filter for collecting particulate matter contained in the exhaust gas is provided in the exhaust gas passage of the device. When a predetermined amount of particulate matter is collected, the filter raises the temperature of the filter by increasing the exhaust temperature of the engine or heating it with a heater, and the collected particulate matter It is intended to burn and remove.

  However, in such a filter, after the particulate matter is burned and removed, the exhaust flow path and pore diameter in the filter are blocked by aggregation of an inorganic compound called ash generated as unburned matter, and the pressure of the exhaust There was a problem that the loss increased.

As used herein, ash means that various additives and impurities contained in the fuel and lubricating oil of the internal combustion engine are combined in the combustion chamber of the internal combustion engine or on the filter to form various compounds. Is produced by agglomeration of the compound in the filter. For example, fuels and lubricating oils for internal combustion engines contain components such as sulfur, phosphorus, calcium, and magnesium, and the components contained in the lubricating oil and the components contained in the mixture are combined in the combustion chamber. , Calcium sulfate (CaSO ₄ ), calcium phosphate (Ca ₃ (PO ₄ ) ₂ ), magnesium sulfate (MgSO ₄ ), and other compounds are formed, and these compounds aggregate together with cocoon (C) to form particulate matter. It will be shaped. That is, since sulfur has a characteristic that it is easily absorbed by soot, sulfur absorbed together with soot is combined with calcium and magnesium in the exhaust gas on the filter, so that calcium sulfate (CaSO ₄ ) and magnesium sulfate (MgSO ₄ ) and the like are produced, and these compounds aggregate as ash.

  As such an ash component, in addition, a technology that lowers the regeneration temperature by mixing an additive containing cerium, iron or the like in a fossil fuel and promoting an oxidation reaction by the additive (inorganic compound) (for example, The compound resulting from the additive used in Patent Documents 1 to 3 is also ash.

  In general, these ash separate from the particulate matter during filter regeneration. The separated ash is less reactive and accumulates in the exhaust gas flow path (cell) in the filter. At this time, the ash has a characteristic of attracting and stacking with other ashes. As a result, the pores in the filter partition walls (cell filtration walls) are clogged, resulting in a problem that the pressure loss increases and the filter characteristics are hindered.

  In order to solve such problems, conventionally, ceramic particles are attached to the surface of the filter by an organic binder or a metal binder, or a technique of ashing off the filter by vibrating the filter (see, for example, Patent Documents 4 and 5). Therefore, a technique (for example, refer to Patent Document 6) that sifts ash together with ceramic particles has been proposed.

  However, in these conventional techniques, the screened ash is accumulated in the longitudinal direction of the through-holes from the vicinity of the sealing portion of the honeycomb structure, so that the filtration area decreases as it is used. There was a problem that the life of the filter was shortened.

  In addition, in order to prevent ash from accumulating in the honeycomb structure, a technique has been proposed in which a cleaning gas is introduced from the opposite direction and the cleaned ash is recovered outside the honeycomb structure. When trying to form a simple system, there is a problem that it becomes extremely complicated.

As another conventional technique, a technique is also proposed in which a collecting material carrying a metal having an electronegativity equal to or lower than a predetermined component contained in a fuel and / or lubricating oil of an internal combustion engine is proposed. (For example, refer to Patent Document 7).
In this prior art, the collector has a metal having an electronegativity equal to or lower than that of a predetermined component contained in the lubricating oil, preferably a metal having an electronegativity lower than that of the predetermined component and a high ionization tendency. Therefore, it is used that the component to be coupled is not the predetermined component but binds to the metal having a low electronegativity.

Furthermore, a technique has been proposed in which a basic metal is supported in the upstream region to form phosphates and sulfates, thereby preventing ash formation with a downstream filter (see, for example, Patent Document 8).
In this technique, for example, potassium sulfate has a lower degree of aggregation than calcium sulfate, so that it can be easily decomposed and removed by using a high-temperature treatment or a reducing atmosphere.

  Further, as another conventional technique, a technique of bonding ceramic particles (silicon carbide or the like) with vitreous is known (see, for example, Patent Documents 9 to 11). However, these techniques are to join ceramic particles with glass for the purpose of producing a filter, not to incorporate ash, and in such a case, the filter itself is melted by glass melting at the joint. However, there was a problem of being destroyed.

In addition to the above-mentioned PM (particulate matter), some of these filters carry a catalyst for oxidative decomposition of hydrocarbon (HC), carbon monoxide (CO), or nitrided oxide (NOx). .
As such a catalyst-carrying filter, for example, a catalyst coat layer carrying alumina is formed on the surface of a partition wall (filter wall) of a honeycomb filter using cordierite or the like, and further, Pt, A material on which a catalytic active component made of a noble metal such as Pd or Rh is supported is well known (Patent Document 12).
As a carrier used for such a catalyst, a fine powder obtained by adding an inorganic binder to γ-alumina, mixing and pulverizing it is used as a slurry, and this slurry is sprayed uniformly on the wall surface of a cordierite honeycomb carrier. Some are made of coated (so-called wash-coated) alumina.

The catalyst coat layer made of alumina is formed of a thin film that uniformly covers the partition wall surface in the cell.
However, the alumina coated with the wash coat on the partition wall has a problem that the pressure loss is remarkably increased because the pore diameter and the porosity are small, easily affected by the ash described above, and the air flow resistance is large.
JP-A-8-218849 JP 2000-167329 A Japanese Patent Laid-Open No. 2001-98925 Japanese Utility Model Publication No. 4-129824 JP-A-8-28247 Japanese Patent Laid-Open No. 10-33923 JP 2001-12229 A JP 2002-371824 A JP 61-26550 A JP-A-8-165171 JP 2001-199777 A Japanese Patent Laid-Open No. 5-68892

About the prior art shown in patent documents 1-12, as mentioned above, it is the actual situation that has various problems which still need a solution.
Therefore, an object of the present invention is to reduce the filter volume or block the exhaust gas flow path (cell) due to the ash generated by the combustion of particulate matter in the exhaust gas being accumulated in the filter. It is an object of the present invention to propose a filter that does not cause problems of increase in pressure loss and deactivation of a catalyst coat layer.
Another object of the present invention is to provide a filter that can not only eliminate maintenance such as replacement with a new product after a certain period of use or removal for ash removal, but also extend the service life with a simple configuration. It is to propose.
Still another object of the present invention is to propose an exhaust gas purification device and an exhaust gas purification method using the filter.

  Inventors, in research aimed at realizing the above objective, ash trapping material particles soften at the filter regeneration temperature (250-800 ° C) and behave like glass components that melt and fluidize. At the same time, they have found that they have the property of attracting each other with ash and depositing. Therefore, removal of ash accompanied by such a deposition phenomenon is not a method of physically peeling and removing as in the prior art, that is, a filter while suppressing a decrease in filter volume and blockage of an exhaust gas passage. It has been found that this is possible by the method of depositing at a specific location inside.

(1) That is, the present invention is a filter for purifying particulate matter-containing exhaust gas discharged from an internal combustion engine, and in the catalyst coat layer formed on the inner partition wall surface of the filter, A filter characterized by containing dispersed ash trapping material particles is proposed.
(2) The present invention is also a filter for purifying particulate matter-containing exhaust gas discharged from an internal combustion engine, and each ceramic particle forming a partition partitioning each cell of the filter. The present invention proposes a filter characterized in that ash trapping material particles are dispersed and contained in the catalyst coat layer coated on the surface.
(3) The present invention is also equipped with a filter for collecting particulate matter contained in the exhaust gas and reducing and removing nitrogen oxides and carbon monoxide in the exhaust gas passage of the internal combustion engine. In the exhaust gas purifying apparatus for an internal combustion engine constructed as described above, an exhaust gas purifying apparatus for an internal combustion engine is proposed in which the filters described in (1) and (2) above are used as the filter.
(4) The present invention further relates to a method for collecting particulate matter in exhaust gas containing particulate matter discharged from an internal combustion engine with a filter, and to capture ash in a catalyst coat layer provided in the cell of the filter. An exhaust gas purifying method for an internal combustion engine, characterized in that the ash contained in the particulate matter is captured by the material particles and confined in the filter to be removed.

  In the present invention, the ash capturing material particles are a glassy material or a low melting point inorganic compound-based flux material, the ash capturing material particles are a low melting point glass, and the catalyst coat layer is an integral type. Alternatively, it is provided on the partition wall surface of the exhaust gas inflow side cell of the aggregate-type honeycomb structure or the laminated honeycomb structure, and the catalyst coat layer is made of alumina supporting the catalyst. Further, the catalyst coat layer is provided with a concentration gradient by increasing the content of ash trapping material particles dispersed and contained downstream from the upstream side along the axial direction of the exhaust gas inflow side cell. Can be used as means for solving the above problems.

  According to the present invention, the ash trapping material particles are dispersed and contained in the catalyst coat layer in the filter, that is, each cell on the exhaust gas inflow side, preferably the catalyst coat layer on the cell end (downstream side end) side. In addition to purifying NOx, HC, and CO in exhaust gas, ash generated by softening or melting during regeneration (for example, around 550 ° C) that burns and removes particulate matter, that is, combustion of particulate matter Ashes separated and produced as unburned products by the above are sequentially adsorbed to the ash trapping material particles in the catalyst coat layer and fixedly deposited there, thereby reducing the filter volume (filtering area) or blocking the exhaust passage. It is possible to provide a long-life filter that minimizes the pressure and does not cause a significant pressure loss.

In addition, according to the exhaust gas purification apparatus of the present invention, it is not necessary to perform maintenance such as replacement with a new one after a certain period of use or removal for ash removal, and the structure is simple, thus realizing low cost. can do.
Furthermore, according to the method of the present invention, in addition to suppressing the generation of NOx, HC, CO, etc., ash can be removed, and higher purification of the internal combustion engine exhaust gas is possible.

  The present invention oxidizes and removes NOx, HC, CO, etc. contained in exhaust gas exhausted from an internal combustion engine, and at the same time, particularly a filter capable of collecting and removing particulate matter in the exhaust gas and mounting the same In the exhaust gas purifying apparatus for an internal combustion engine, the ash that is easily softened or further melted at the regeneration temperature of the filter and separated during the regeneration of the filter and remains as unburned product is generated in the filter, particularly in the exhaust gas. It is characterized in that it is trapped (captured) in the catalyst coat layer provided on the surface of the partition wall in each cell on the inflow side or the surface of each ceramic particle in the partition wall itself.

  Therefore, in the present invention, in the catalyst coating layer, an ash trapping material particle, that is, a material that softens or at least partially generates a liquid phase at a filter regeneration temperature (250 ° C. to 800 ° C.). It is dispersed and contained.

  Such an ash capturing material is a vitreous material that preferably changes from a solid phase to a liquid phase in the regeneration temperature range of the filter, or at least softens to generate fluidity, preferably phosphate glass or calcium sulfate glass. It is preferable to use low melting point glass particles such as low melting point inorganic compound flux material particles.

Examples of the phosphate glass include P ₂ O ₃ —BaO (glass transition temperature: 377 ° C.), P ₂ O ₃ —ZnO (glass transition temperature: 366 ° C.), P ₂ O ₃ —BaO—BaF ₂ (glass transition). Temperature: 366 ° C.) or the like.
Examples of calcium sulfate glass include CaSO ₄ —NaCl (minimum liquidus temperature: 726 ° C.), CaSO ₄ —KCl (minimum liquidus temperature: 687 ° C.), and CaSO ₄ —NaCl—KCl (minimum liquidus temperature: 605). ° C) or the like.

As the low melting point inorganic compound-based flux material, it is preferable to use a sulfate-based flux or an alkali chloride-containing sulfate-based flux (hereinafter referred to as “chloride-containing flux”). Examples of the sulfate flux include Li ₂ SO ₄ -0.5Na ₂ SO ₄ + 0.5K ₂ SO ₄ (minimum melting temperature: 521 ° C), Na ₂ SO ₄ -ZnSO ₄ (minimum melting temperature: 456 ° C), and the like. Can be used. The chloride-containing flux includes Li ₂ SO ₄ —K ₂ SO ₄ —NaCl (minimum melting temperature: 432 ° C.), Li ₂ SO ₄ —NaCl (minimum melting temperature: 499 ° C.), Li ₂ SO ₄ -NaCl-KCl (minimum melting temperature: 426 ° C.) or the like can be used.

Hereinafter, a filter according to the present invention and an exhaust gas purification apparatus for an internal combustion engine using the filter will be specifically described with reference to the drawings.
Here, an embodiment in which the filter according to the present invention is a honeycomb structure and the exhaust gas purifying apparatus according to the present invention is applied to a vehicle diesel engine will be described.

  The filter according to the present invention uses a honeycomb structure in which a large number of cells (through holes) are arranged in parallel in the longitudinal direction with partition walls (filtration walls) therebetween. This is because with such a structure, the filtration area per volume of the filter can be increased, and particulates can be efficiently and thinly collected.

  As such a honeycomb structure, a plurality of honeycomb structures made of a columnar porous ceramic member in which a large number of cells are arranged in parallel in the longitudinal direction with a partition wall therebetween are bound and integrated through a sealing material layer. An aggregate (hereinafter referred to as an “aggregate-type honeycomb structure”), or a honeycomb structure (hereinafter, referred to as an “integrated honeycomb structure”) composed of a single porous ceramic member. A plate-like (sheet-like) porous ceramic member is laminated in the thickness direction and stacked, and a columnar honeycomb structure (hereinafter referred to as this) in which cell holes are continuously arranged in the longitudinal direction with a partition wall therebetween. Is referred to as a “laminated honeycomb structure”).

FIG. 1 is a perspective view schematically showing an example of an aggregate-type honeycomb structure that is an example of the honeycomb structure, and FIG. 2A is a porous diagram of the aggregate-type honeycomb structure shown in FIG. It is a perspective view of a ceramic member (unit), and the same figure (b) is an AA line arrow sectional view of a porous ceramic member shown in (a).
In the honeycomb structure 10 shown in FIG. 1, a prismatic porous ceramic member (unit) 20 shown in FIG. 2 is combined through a sealing material layer 14 to form a cylindrical ceramic block 15. A sealing material layer 13 is provided on the outer periphery of the ceramic block 15. The prismatic porous ceramic member 20 is provided with a large number of cells (through holes) 21 along the longitudinal direction thereof.

  For example, when the honeycomb structure 10 shown in FIG. 1 is used as a filter for collecting the particulate matter in the exhaust gas, the porous ceramic member 20 is made of these as shown in FIG. It is necessary that either one of the openings at both ends of the cell 21 has a structure sealed with a sealing material (plug) 22.

  That is, to use this honeycomb structure 10 as a filter, one (exhaust gas inflow side) cell 21 of the ceramic block 15 is sealed at its downstream end (cell end) by the sealing material 22. In the adjacent (exhaust gas outflow side) cell 21, the upstream end is sealed with the sealing material 22, and so-called these adjacent cells 21 are alternately sealed on the exhaust gas inflow side and the exhaust gas outflow side. It has a structured.

  In such a filter, as shown in FIG. 2B, the exhaust gas that has flowed into the exhaust gas inflow side cell 21a passes through the partition wall 23 that separates the cells 21a, and is on the exhaust gas outflow side. After moving to the cell 21b, it flows out, and the partition wall 23 separating the cells 21a and 21b functions as a particle collecting filter.

  Fig. 3 (a) is a perspective view schematically showing another embodiment of the honeycomb structure, that is, a specific example of the integrated honeycomb structure, and Fig. 3 (b) is a view taken along the line B-B of Fig. 3 (a). It is sectional drawing. As shown in this figure, the integrated honeycomb structure 30 includes a columnar ceramic made of a single columnar porous ceramic member in which a large number of cells 31a and 31b are provided along a longitudinal direction with a partition wall 33 therebetween. It is formed by the block 35.

  In the honeycomb structure 30, the downstream end is sealed with the sealing material 32 at the end of the exhaust gas inflow side cell 31a, and the upstream end is the sealing material at the end of the exhaust gas outflow side cell 31b. 32, when the exhaust gas flowing into one cell 31a passes through the partition wall 33 separating these cells 31a and then flows out from the other cell 31b, the partition wall 33 collects particles. It functions as a filter.

  Examples of the material of the honeycomb structure described above include, for example, oxide ceramics such as cordierite, alumina, silica, mullite, zirconia, and yttria, carbide ceramics such as silicon carbide, zirconium carbide, titanium carbide, tantalum carbide, and tungsten carbide, aluminum nitride Further, nitride ceramics such as silicon nitride, boron nitride, and titanium nitride, aluminum titanate, a composite of the above ceramic and silicon, and the like can be used.

  In particular, when the honeycomb structure is an aggregate-type honeycomb structure as shown in FIG. 1, among the ceramics, the heat resistance is high, the mechanical characteristics and the chemical stability are excellent, and the heat conduction is performed. It is desirable to use silicon carbide having a high rate.

  On the other hand, when the honeycomb structure is an integral honeycomb structure as shown in FIG. 3, it is preferable to use an oxide ceramic such as cordierite. This is because it can be manufactured at low cost, has a relatively low coefficient of thermal expansion, is rarely destroyed during use, and is not oxidized.

  In the honeycomb structure shown in FIGS. 1 and 3, the shape of the ceramic block is a columnar shape. However, in the present invention, the ceramic block is not limited to a columnar shape as long as it is a columnar shape. It may have a shape such as a prism.

  The porosity of the ceramic block is preferably about 20 to 80%. The reason is that when the porosity is less than 20%, clogging occurs immediately when the honeycomb structure is used as a honeycomb filter. On the other hand, when the porosity exceeds 80%, the strength of the ceramic block decreases. This is because it is easily destroyed. The porosity can be measured by a conventionally known method such as a mercury intrusion method, an Archimedes method, or a measurement using a scanning electron microscope (SEM).

  The average pore diameter of the ceramic block is preferably about 5 to 100 μm. The reason is that when the average pore diameter is less than 5 μm, when the honeycomb structure is used as a filter, the particulates are easily clogged. On the other hand, when the average pore diameter exceeds 100 μm, the particulates are pores. This is because the particulates cannot be collected and cannot function as a filter.

  When the honeycomb structure forming the filter according to the present invention is the aggregate type honeycomb structure shown in FIG. 1, the sealing material layers 13 and 14 are provided between the porous ceramic members 20 or the outer periphery of the ceramic block 15. It arrange | positions so that these may be enclosed in a part. The sealing material layer 14 interposed between the porous ceramic members 20 functions as an adhesive that binds the plurality of porous ceramic members 20 together, while the sealing material layer 13 formed on the outer peripheral portion of the ceramic block 15. When the honeycomb structure is used as a filter, it functions to prevent the exhaust gas from leaking from the outer periphery of the ceramic block 15 when the honeycomb structure 10 is installed in the exhaust passage of the internal combustion engine.

  Next, FIG. 4 is a perspective view of a laminated honeycomb structure which is another embodiment of the filter according to the present invention, FIG. 4 (a) is a perspective view, and FIG. It is CC sectional view taken on the line of the porous ceramic member shown in FIG.

This type of filter is a laminate formed by laminating plate-like sheets (thickness of about 0.1 to 20 mm) in the thickness direction, that is, in the longitudinal direction of the filter, and through holes for cells in the longitudinal direction. Are overlapped to form a cell 41 to form a honeycomb structure.
Here, the term “stacked so that the cell through holes are overlapped” means that the through holes formed in adjacent sheet-like materials communicate with each other to form the cell 41.

  The sheet-like material is preferably made of ceramic, metal or the like, but in the present invention, it is preferably mainly made of inorganic fibers. When the sheet-like material is made of inorganic fibers, it can be easily produced by a papermaking method or the like, and a honeycomb structure made of a laminated body can be manufactured by laminating them. In addition, this laminated body may adhere | attach with an inorganic adhesive material etc., and what was simply laminated | stacked physically may be sufficient. When manufacturing such a laminated body, it is good also as a honeycomb structure by inserting directly in the casing (metal cylindrical body) with which it mounts to an exhaust pipe, and making it laminate | stack by applying a pressure.

In the honeycomb structure 40, a large number of cells 41a, in which one end portion of the cells, that is, the downstream end on the exhaust gas inflow side is sealed, are arranged in parallel in the longitudinal direction with the partition wall 43 therebetween, and serve as a filter. A functioning cylindrical shape.
That is, as shown in FIG. 4B, the end of the cell corresponding to the inlet side or the outlet side of the exhaust gas is sealed, and the exhaust gas flowing into one cell 41a After passing through the partition wall 43 separating the cells, it flows out from the other cell 41b and functions as a filter.

In this honeycomb structure 40, the thickness of the partition walls separating the cells 41a and 41b is preferably in the range of 0.2 to 10.0 mm, and more preferably in the range of 0.3 to 6.0 mm. The density of the cells in the cross section perpendicular to the longitudinal direction of the honeycomb structure is preferably 0.16 / cm ² (1.0 / in ² ) to 62 / cm ² (400 / in ² ), A range of about 0.62 pieces / cm ² (4.0 pieces / in ² ) to 31 pieces / cm ² (200 pieces / in ² ) is more desirable.

  Examples of the material of the inorganic fiber include oxide ceramics such as silica-alumina, mullite, alumina, and silica, nitride ceramics such as aluminum nitride, silicon nitride, boron nitride, and titanium nitride, silicon carbide, zirconium carbide, and titanium carbide. Further, carbide ceramics such as tantalum carbide and tungsten carbide can be used. These may be used alone or in combination of two or more.

  In addition, this inorganic fiber may carry | support the catalyst which consists of noble metals, such as platinum, palladium, and rhodium. Further, in addition to the noble metal, an alkali metal (element periodic table group 1), an alkaline earth metal (element periodic table group 2), a rare earth element (element periodic table group 3), or a transition metal element may be added.

The fiber length of the inorganic fiber is desirably 0.1 mm to 100 mm, and more desirably 0.5 mm to 50 mm. Further, the fiber diameter of the inorganic fiber is preferably 1 μm to 30 μm, and more preferably 2 μm to 10 μm.
In addition to the inorganic fibers, the honeycomb structure 40 is made of inorganic glass such as silicate glass, alkali silicate glass, borosilicate glass, alumina sol, silica sol for bonding these inorganic fibers to maintain a certain shape. In addition, a binder such as titania sol may be included.

  The honeycomb structure 40 may include a small amount of inorganic particles and metal particles. As the inorganic particles, for example, carbides, nitrides, oxides and the like can be used. Specifically, inorganic powders made of silicon carbide, silicon nitride, boron nitride, alumina, silica, zirconia, titania, etc. Can be used.

As said metal particle, metal silicon, aluminum, iron, titanium etc. can be used, for example. These may be used alone or in combination of two or more.
The apparent density of the honeycomb structure ^is desirably ^{0.05g / cm 3 ~1.00g / cm 3} , and more desirably at ^{0.10g / cm 3 ~0.50g / cm 3} .

  Moreover, the porosity of the honeycomb structure is preferably 60% to 98%, and more preferably 80% to 95%.

  As described above, the catalyst is supported in the cells of the honeycomb structure, that is, on the surface of the partition walls or in the interior, so that the filter using the honeycomb structure collects and removes particulate matter in the exhaust gas, In addition to functioning as a filter that can perform a regeneration process, it can function as a catalytic converter for purifying CO, HC, NOx, and the like contained in exhaust gas.

  Next, a characteristic structure in the present invention is that the filter is regenerated on the cell walls, that is, the partition walls 23, 33, and 43 that separate the cells 21, 31, 41 of the honeycomb structure 10, 20, 30, 40. At the time of application, a catalyst coat layer 100 carrying a catalyst such as Pt for promoting the combustion of particulate matter is provided. That is, by providing the honeycomb structure with a catalyst coat layer 100 supporting a catalyst such as a noble metal such as Pt, Rh, Pd or an alloy thereof, a combustion apparatus such as a heat engine such as an internal combustion engine or a boiler. It is possible to purify HC, CO, NOx and the like in the exhaust gas discharged from the exhaust gas, and at the same time, contribute to the promotion of combustion of the particulate matter described above.

In addition, a more characteristic configuration in the present invention is that an ash trapping material particle (particle diameter: 0.1 μm to 100 μm) for adsorbing and removing ash separated and generated from the particulate matter during the regeneration treatment in the catalyst coat layer Is dispersed.
As described above, when the ash capturing material particles are dispersed and contained in the catalyst coat layer, the ash that has been detached from the soot at the time of the regeneration treatment and softened or partially melted is heated in the coat layer. Ash trapping material particles (also at least in a softened state) attract each other, deposit around them and are trapped and deposited there, so that the ash generated during the regeneration process is placed in a specific location within the filter cell. Can be trapped and removed.

  That is, in the filter according to the present invention, what is important is that the honeycomb structure of the aggregate-type honeycomb structure 10, the integral-type honeycomb structure 30, or the laminated honeycomb structure 40 as described above, In the catalyst coat layer 100 formed on the surface of the partition walls of the exhaust gas inflow side cells 21a, 31a, 41a or on the respective surfaces of the constituent particles in the partition walls, preferably in the catalyst coat layer located on the downstream side thereof, The ash capturing material particles made of a glassy material such as a low-melting glass or a low-melting-point inorganic compound-based flux material are dispersedly contained.

  The low-melting glass is a phosphate glass that is softened or at least partially melted at a temperature at which particulates collected during the regeneration treatment can be burned and removed, that is, at a filter regeneration temperature (250 to 800 ° C.). It is preferable to use an inorganic compound that vitrifies, such as calcium sulfate-based glass, and the low melting-point inorganic compound-based flux material is a sulfate-based material that softens or at least partially melts within the above temperature range. It is preferable to use a flux or a chloride-containing flux. These materials may be used in combination of two or more.

  When the ash capturing material particles are dispersed and contained in the catalyst coat layer 100, the detailed mechanism that can capture and collect the ash separated from the particulate matter has not been completely elucidated so far. I think that it is as follows. That is, when the particulate matter (particulate) is combusted during the regeneration of the filter, the ash component left as an unburned product is blown away by the exhaust gas. The ash thus blown is softened and becomes a partially molten fluidized state and vitrifies. The glassy ash flying in such a fluidized state attracts and separates all of the separated ash scavenger particles (heated and softened as well) already in the catalyst coat layer in an attempt to attract and bond with each other. Softened ash will accumulate around these ash trapping material particles. The softened glass or flux produced in this way is densely accumulated only on that part and sticks to it, which causes the ash to be deposited locally at the trapping material in the filter. Therefore, clogging is minimized, and even when the filter is used for a long time, the filtration area is not reduced and pressure loss is not caused.

In the present invention, the ash trapping material particles dispersed and contained in the catalyst coat layer 100 have a higher content on the cell end portion side on the exhaust gas outflow side than in the upstream side into which the exhaust gas flows in at a high concentration. It is preferable to provide a concentration gradient.
This is because, when ash is trapped in the partition wall, new ash is adsorbed on the ash trap layer and fills the pores of the partition wall, increasing the resistance when exhaust gas flows in and increasing pressure loss. Because it will do.

    Therefore, the ash capturing material particles are desirably dispersed and contained in the catalyst coat layer on the side closer to the downstream side of the partition walls. The reason for this is that when the separated ash is trapped near the outflow side end of the exhaust gas inflow side cell, the ash accumulates in the vicinity of the downstream end, so that the filtration area can be reduced. This is because it can be minimized.

  Hereinafter, a method for manufacturing the aggregated honeycomb structure 10 and the integral honeycomb structure 30 forming the filter according to the present invention will be briefly described.

  For example, when the honeycomb structure is an integrated honeycomb structure 30 formed as a single ceramic block as shown in FIG. 3, first, any one of the above ceramic particles is mainly used. Extrusion molding is performed using a raw material paste as a component, and a ceramic molded body having substantially the same shape as the honeycomb structure 30 shown in FIG. 3 is produced.

  As the raw material paste to be used, it is desirable that the porosity of the manufactured ceramic block is 20 to 80%. For example, ceramic particle powder having a large average particle size and ceramic particles having a small average particle size It is more preferable to add a binder such as methyl cellulose or carboxymethyl cellulose to a mixed powder consisting of and an organic solvent such as benzene and a dispersion medium such as methanol.

  Next, the mixed powder, binder, and dispersion medium liquid composed of the ceramic powder and the like are mixed with an attritor or the like and sufficiently kneaded with a kneader or the like to obtain a raw material paste, and then the raw material paste is extruded to form the ceramic. A molded body is produced. The raw material paste may be added with a molding aid such as ethylene glycol, dextrin, and fatty acid soap, or a pore-forming agent such as spherical acrylic particles and graphite, if necessary.

  Next, the ceramic molded body is dried using a microwave dryer, a hot air dryer, a dielectric dryer, a vacuum dryer, a vacuum dryer, a freeze dryer or the like to obtain a ceramic dried body, and then a predetermined cell. One end of the substrate is filled with a paste as a sealing material, and a sealing process is performed to seal the cells.

  Next, the ceramic dry body filled with the sealing material paste is heated to about 150 to 700 ° C., and the binder contained in the ceramic dry body is removed to perform a degreasing process to obtain a ceramic degreased body. Thereafter, the ceramic degreased body is heated to about 1400-2100 ° C. to produce a ceramic porous body.

  The thus manufactured honeycomb structure has a structure in which the exhaust gas inflow side cell is filled with a sealing material and sealed, and is suitably used as the above-described honeycomb filter for exhaust gas purification. be able to.

Thereafter, each of the partition walls has a Pt for purifying the combustion of particulate matter and purifying CO, NC, NOx, etc. in the exhaust gas when the honeycomb filter is subjected to regeneration treatment on the surface or in the partition walls. At the same time as supporting a catalyst such as a catalyst coat layer formed by dispersing and containing ash trapping material particles. As a method of forming this catalyst coat layer,
(1) As a method of coating the partition wall surface, the alumina particles are adjusted by adjusting the alumina slurry to have a relatively large viscosity or by flowing a slurry having a larger particle diameter of alumina used in the alumina slurry into the cell. It is formed by adhering to the partition wall surface.
(2) As a method of coating the surface of each particle in the partition wall, an alumina slurry having a relatively low viscosity is prepared, or a slurry in which the particle diameter of alumina used for the alumina slurry is reduced, for example, by adjusting the pressure. It is poured so as to permeate until it forms, or it is formed using a sol-gel method.

  Next, when the honeycomb structure is an aggregated honeycomb structure 10 in which a plurality of porous ceramic members are bundled through a sealing material layer as shown in FIG. Extrusion molding is performed using the above-described raw material paste mainly composed of ceramic particles and silicon, and a generated shape having a shape like the porous ceramic member 20 shown in FIG. 2 is produced. The raw material paste may be the same as the raw material paste described in the above-described integrated honeycomb structure 30, but preferably uses silicon carbide as the main material.

  Next, the generated shaped body is dried using a microwave dryer or the like to form a dried body, and then a sealing material paste that becomes a sealing material at the end of the cell on the exhaust gas inflow side of the dried body Is sealed, and the outlet side of the cell is sealed. Further, the upstream end of the exhaust gas outflow side cell adjacent to the exhaust gas inflow side is similarly sealed with a sealing material.

  Next, the dried body that has been subjected to the sealing process alternately as described above is subjected to a degreasing process under the same conditions as those of the integrated honeycomb structure 30 described above, and then fired to obtain a plurality of cells. Can produce a porous ceramic member having a partition wall in parallel in the longitudinal direction.

  And the process of apply | coating and laminating | sealing the sealing material paste used as a sealing material layer with uniform thickness on the side surface of the porous ceramic member 20 is repeated, and the laminated body of the rectangular ceramic porous ceramic member 20 of a predetermined | prescribed magnitude | size is obtained. Make it.

  Next, the laminated body of the porous ceramic member 20 is heated to dry and solidify the sealing material paste layer 51 to form the sealing material layer 14, and then, for example, the outer peripheral portion of FIG. The ceramic block 15 is produced by cutting into a shape as shown in FIG.

  Furthermore, the sealing material layer 13 is formed on the outer periphery of the ceramic block 15 by using the sealing material paste, thereby manufacturing a honeycomb structure in which a plurality of porous ceramic members are bound through the sealing material layer. be able to.

  The aggregated honeycomb structure 10 manufactured in this way is such that the end of a predetermined cell of a ceramic block (porous ceramic member) is filled with a sealing material and sealed, and the exhaust gas purification described above is performed. It can be suitably used as a honeycomb filter.

Thereafter, each of the partition walls has a Pt for purifying the combustion of particulate matter and purifying CO, NC, NOx, etc. in the exhaust gas when the honeycomb filter is subjected to regeneration treatment on the surface or in the partition walls. At the same time as supporting a catalyst such as a catalyst coat layer formed by dispersing and containing ash trapping material particles. As a method of forming this catalyst coat layer,
(1) As a method of coating the partition wall surface, the alumina particles are adjusted by adjusting the alumina slurry to have a relatively large viscosity or by flowing a slurry having a larger particle diameter of alumina used in the alumina slurry into the cell. It is formed by adhering to the partition wall surface.
(2) As a method of coating the surface of each particle in the partition wall, an alumina slurry having a relatively low viscosity is prepared, or a slurry in which the particle diameter of alumina used for the alumina slurry is reduced, for example, by adjusting the pressure. It is poured so as to permeate until it forms, or it is formed using a sol-gel method.

  Next, a method for manufacturing a laminated honeycomb structure will be described with reference to FIG.

(1) An inorganic fiber such as an alumina fiber is dispersed at a rate of 5 to 100 g with respect to 1 liter of water. In addition, an inorganic binder such as silica sol is 10 to 40 parts by weight with respect to 100 parts by weight of the inorganic fiber, such as acrylic latex. An organic binder is added at a ratio of 1 to 10 parts by weight, and if necessary, a coagulant such as aluminum sulfate and a flocculant such as polyacrylamide are added in a small amount, and the slurry for papermaking is prepared by sufficiently stirring.

(3) The slurry obtained in the above (1) is made with a perforated mesh in which holes having a predetermined shape are formed in a checkered pattern at predetermined intervals, and the obtained slurry has a temperature of about 100 to 200 ° C. Is dried to obtain a papermaking sheet 40a having a predetermined thickness as shown in FIG. The thickness of the papermaking sheet 40a is preferably 0.1 to 20 mm. In addition, in order to seal an edge part in a checkered pattern, the papermaking sheet 40b for both ends is obtained by similarly making paper using a mesh. If several sheets of paper are used at both ends, a honeycomb structure functioning as a filter can be obtained without requiring a step of closing predetermined cells at both ends after cells are formed.

(3) As shown in FIG. 5 (b), using a cylindrical casing 42 having a holding metal fitting on one side, first, several sheets of papermaking sheets 40b for both ends are stacked in the casing 43. Then, a predetermined number of internal papermaking sheets 40a are laminated. And finally, several sheets of paper-making sheet 40b for both ends are laminated, and further pressed, and then the other side of the sheet is installed and fixed with a restraining metal fitting to complete the honeycomb structure up to canning. Make it. In this step, it is necessary to stack the papermaking sheets 40a and 40b so that the cells overlap.

  Each of the partition wall surfaces of the honeycomb structure thus obtained or the surface of the ceramic particles constituting the partition walls is uniformly or individually coated with an alumina thin film as a catalyst coating layer at a predetermined thickness, and A catalytic active component such as Pt or Pd (hereinafter simply referred to as “active component”) is supported on the catalyst coating surface made of this alumina thin film and the like, and at the same time, the ash capturing material particles are dispersed and contained.

Thereafter, each of the partition walls has a Pt for purifying the combustion of particulate matter and purifying CO, NC, NOx, etc. in the exhaust gas when the honeycomb filter is subjected to regeneration treatment on the surface or in the partition walls. At the same time as supporting a catalyst such as a catalyst coat layer formed by dispersing and containing ash trapping material particles. As a method of forming this catalyst coat layer,
(1) As a method of coating the partition wall surface, the alumina particles are adjusted by adjusting the alumina slurry to have a relatively large viscosity or by flowing a slurry having a larger particle diameter of alumina used in the alumina slurry into the cell. It is formed by adhering to the partition wall surface.
(2) As a method of coating the surface of each particle in the partition wall, an alumina slurry having a relatively low viscosity is prepared, or a slurry in which the particle diameter of alumina used for the alumina slurry is reduced, for example, by adjusting the pressure. It is poured so as to permeate until it forms, or it is formed using a sol-gel method.

In the present invention, the catalyst coat layer 100 containing the catalyst and the ash trapping material particles, which is the most characteristic configuration, is a layer in which the surface of the partition wall or the surface of each ceramic particle constituting the partition wall is coated with an alumina film or the like. It is.
FIG. 6 is an example in which an alumina layer is formed on the partition wall by a wash coat method, and the figure shows a state in which an alumina film is individually coated on each surface of each ceramic particle constituting the partition wall. Shows things.

  Thus, the catalyst coat layer 100 (alumina film), which is a characteristic configuration of the filter according to the present invention, is formed of an alumina film on the surface of the partition wall facing the exhaust gas inflow side which is an exhaust gas filtration wall. The surface of each ceramic particle constituting the partition wall is individually coated with an alumina film. In particular, in the latter case, the pores exist as they are without closing the pores of the partition walls themselves, that is, the gaps formed between the particles (especially when they are formed on the downstream side). small.

The alumina film constituting the substrate portion of the catalyst coat layer 100, that is, the crystal structure of the alumina film is at least one of γ-Al ₂ O ₃ , δ-Al ₂ O ₃ , and θ-Al ₂ O _3. It contains. The Bet specific surface area of alumina based on alumina is preferably 50 to 800 m ² / g.

  Pt, Rh, Pd, Ce, Cu, V, Fe, Au, Ag, or the like is used as an active component to be supported in the catalyst coat layer 100 made of an alumina film. Various methods are conceivable for supporting these active components on the alumina-supported film, and impregnation methods such as evaporation to dryness, equilibrium adsorption, incipient wetness, or spray can be applied.

  FIG. 7 is a cross-sectional view showing an example of an exhaust gas purifying device for a vehicle in which the above-described honeycomb structure, that is, a filter of the present invention provided with a catalyst coat layer is installed. In this figure, an exhaust gas purification apparatus 600 mainly includes a honeycomb filter 60 according to the present invention, a casing 630 that covers the outside of the honeycomb filter 60, and a holding seal disposed between the honeycomb filter 60 and the casing 630. It is composed of a material 620 and heating means 610 provided on the exhaust gas inflow side of the honeycomb filter 60.

  An exhaust introduction pipe 640 connected to an internal combustion engine such as an engine is connected to an end portion of the casing 630 where exhaust gas is introduced, and the other end portion of the casing 630 is connected to the outside. A discharge pipe 650 is connected.

  In such an exhaust gas purification device 600, exhaust gas discharged from an internal combustion engine such as an engine is introduced into the casing 630 through the introduction pipe exhaust pipe 640, passes through the partition walls from the cells of the honeycomb filter 60, and passes through the partition walls. After collecting the particulates and purifying the exhaust gas, the particulates are discharged to the outside through the discharge pipe 650.

  When a large amount of particulates accumulates on the partition walls of the honeycomb filter 60 and the pressure loss increases, the regeneration process of the honeycomb filter 60 is performed. In the regeneration process, the gas heated using the heating means 610 is caused to flow into the cells of the honeycomb filter 60 to heat the honeycomb filter 60, and the particulate matter deposited on the partition walls is burned and removed by the heating. .

  The regeneration of the filter means that the collected particulate matter is burned, but the regeneration method may be a method in which the honeycomb structure is heated by heating means provided on the exhaust gas inflow side. Well, by supporting the oxidation catalyst on the honeycomb structure and utilizing the heat generated by the oxidation of hydrocarbons in the exhaust gas by this oxidation catalyst, regeneration is performed in parallel with the purification of the exhaust gas. There may be.

  In general, in a diesel engine, the exhaust gas has a relatively high oxygen concentration. Therefore, the regeneration treatment of the exhaust gas purification device for the diesel engine has a relatively high oxygen concentration or has an oxygen storage effect such as rare earth elements. Usually, the reaction is carried out in an excess oxygen atmosphere due to the action of the catalyst. Accordingly, when the regeneration temperature exceeds 800 ° C., the vitreous material or flux material for trapping ash is melted and easily flows from the filter which is a porous body. On the other hand, if it is less than 250 ° C., the glass or flux does not melt, so that it does not function to take in and fix the ash.

  In preparing the filter according to the present invention, the vitreous material or the inorganic compound-based flux material is melted and reduced in viscosity in a temperature range of 250 ° C. to 800 ° C., and the possibility as a material enabling ash trapping is investigated. The above tests were conducted in advance, and 11 types (Test Examples 1 to 11) as applicable glassy materials and 5 types (Test Examples 12 to 16) as inorganic compound-based flux materials were selected. The results are shown in Table 1.

  The above test was conducted using a thermogravimetric / differential thermal analyzer (TG / DTA) (Seiko Electronics Co., Ltd., product name: TG / DTA220U). The minimum liquidus temperature, the minimum melting temperature, and the glass transition temperature of the material were determined, and the applicability was judged.

Examples in which the 16 types of ash capturing materials selected based on the test results are applied to an integral / aggregate / stacked honeycomb structure will be described in detail below. It is not limited to examples only.
The following Examples 1 to 24 are examples of an integral honeycomb structure, Examples 25 to 48 are examples of an aggregated honeycomb structure, and Examples 49 to 72 are stacked honeycomb structures. It is an example.

(1) Using a commercially available cordierite, a cylindrical porous ceramic member having a porosity of 45%, an average pore diameter of 20 μm, a diameter of 144 mm, and a length of 254 mm was produced. This was a honeycomb structure that functions as a honeycomb filter for exhaust gas purification.

(2) To the honeycomb structure, as an ash capturing material, P ₂ O ₃ glass as shown in Test Example 1 is made into a powder form having a diameter of about 5 μm using a ball mill, and this is mixed with an alumina slurry. And poured into the exhaust gas inflow side cell. Then, it dried and heated to the slurry adjustment temperature (400 degreeC) vicinity of each ash capture | acquisition material, and the catalyst coat layer containing this ash capture | acquisition material and a catalyst was created on the partition wall surface. Furthermore, a Pt complex whose concentration is adjusted with water is poured into the cell, dried and similarly heated to the vicinity of the slurry adjustment temperature of each ash trapping material, and the Pt catalyst is supported on the surface of the catalyst coat layer on the partition wall surface. It was.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 2 is treated with the ash capturing material by the same treatment as in Example 1 (2). The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 3 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of an ash capturing material, P ₂ O ₃ -based glass powder as shown in Test Example 4 is treated with the ash capturing material by the same process as in (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 5 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 6 is treated with the ash capturing material by the same treatment as in (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 7 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 8 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 9 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 10 is treated with the ash capturing material by the same process as in (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, P ₂ O ₃ glass powder as shown in Test Example 11 is treated with the ash capturing material by the same treatment as (2) of Example 1. The alumina slurry contained was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 12 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of an ash capturing material, CaSO ₄ glass powder as shown in Test Example 13 is treated with alumina containing an ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 14 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 15 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 16 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of an ash capturing material, CaSO ₄ glass powder as shown in Test Example 17 is treated with alumina containing an ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 18 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of the ash capturing material, CaSO ₄ glass powder as shown in Test Example 19 is treated with alumina containing the ash capturing material by the same treatment as in (2) of Example 1. The slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) As an example of an ash capturing material, flux A (sulfide-based flux) powder as shown in Test Example 20 is pulverized into this honeycomb structure by the same treatment as (2) of Example 1. The alumina slurry containing the material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) As an example of an ash trapping material, flux A (sulfide-based flux) powder as shown in Test Example 21 is ash trapped in this honeycomb structure by the same treatment as in (2) of Example 1. The alumina slurry containing the material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) In this honeycomb structure, as an example of the ash capturing material, a powder of flux B (chloride-containing flux) as shown in Test Example 22 is included in the ash capturing material by the same treatment as in Example 1. Alumina slurry was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) As an example of an ash capturing material, flux B (chloride-containing flux) powder as shown in Test Example 23 is ashed into the honeycomb structure by the same treatment as in Example 1 (2). An alumina slurry containing the trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure similar to (1) of Example 1 was used.
(2) To this honeycomb structure, as an example of an ash capturing material, powder of flux B (chloride-containing flux) as shown in Test Example 24 is treated with ash by the same treatment as (2) of Example 1. An alumina slurry containing the trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

Comparative Example 1

(1) A honeycomb structure was only manufactured in the same manner as in (1) of Example 1, and no ash trapping material was dispersed in the catalyst coat layer.

(1) 80% by weight of silicon carbide powder having an average particle size of 30 μm and 20% by weight of silicon carbide powder having an average particle size of 0.5 μm are wet-mixed, and 100 parts by weight of the obtained mixed powder is mixed with an organic binder ( 6 parts by weight of methylcellulose), 2.5 parts by weight of surfactant (oleic acid) and 24 parts by weight of water were added and kneaded to prepare a raw material paste.
Next, the raw material paste was filled in an extrusion molding machine, and a formed body having substantially the same shape as the porous ceramic member 30 shown in FIG. 23 was produced at an extrusion speed of 10 cm / min.
After the formed form is dried using a microwave dryer to form a ceramic dry body, one end of a predetermined through-hole is filled with a sealing material paste having the same composition as the formed form, and then the dryer is again connected. And degreased for 3 hours at 550 ° C. in an oxidizing atmosphere to obtain a ceramic degreased body.

  The ceramic degreased body is fired at 2150 ° C. for 2 hours under an atmospheric pressure of argon atmosphere to obtain a porosity of 45%, an average pore diameter of 10 μm, and a size of 34.3 mm × 34.3 mm × 254 mm. A porous ceramic member was produced.

(2) 30% by weight of alumina fiber having a fiber length of 0.2 mm, 21% by weight of silicon carbide particles having an average particle diameter of 0.6 μm, 15% by weight of silica sol, 5.6% by weight of carboxymethyl cellulose, and 28.4% by weight of water A plurality of the porous ceramic members are bound by the method described with reference to FIG. 5 using a heat-resistant sealing material paste containing, and then cut using a diamond cutter to form a cylindrical shape having a diameter of 144 mm. A ceramic block was prepared.
At this time, it adjusted so that the thickness of the sealing material layer which binds the said porous ceramic member might be set to 1.0 mm.

  Next, ceramic fiber made of alumina silicate as inorganic fiber (shot content: 3%, fiber length: 0.1 to 100 mm) 23.3% by weight, silicon carbide powder 30.2 having an average particle size of 0.3 μm as inorganic particles Mixing and kneading 7% by weight of silica sol (content of SiO2 in the sol: 30% by weight) as an inorganic binder, 0.5% by weight of carboxymethyl cellulose and 39% by weight of water as an organic binder, and preparing a sealing material paste did.

  A sealing material paste layer having a thickness of 1.0 mm was formed on the outer periphery of the ceramic block using the sealing material paste. And this sealing material paste layer was dried at 120 degreeC, and the honeycomb structure which functions as a honeycomb-shaped honeycomb filter for exhaust gas purification was manufactured.

(3) To the honeycomb structure, as a ash capturing material, P ₂ O ₃ glass as shown in Test Example 1 is made into a powder form having a diameter of about 5 μm using a ball mill, and this is mixed with an alumina slurry. And poured into the exhaust gas inflow side cell. Then, it dried and heated to the slurry adjustment temperature (400 degreeC) vicinity of each ash capture | acquisition material, and the catalyst coat layer containing this ash capture | acquisition material was created on the partition wall surface. Furthermore, a Pt complex whose concentration is adjusted with water is poured into the cell, dried and similarly heated to the vicinity of the slurry adjustment temperature of each ash trapping material, and the Pt catalyst is supported on the surface of the catalyst coat layer on the partition wall surface. It was.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in the above (1) and (2) uses P ₂ O ₃ glass powder as shown in Test Example 2 as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in the above (1) and (2) uses P ₂ O ₃ glass powder as shown in Test Example 3 as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.
(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in (1) above was treated with P ₂ O ₃ glass powder as shown in Test Example 3 in the same manner as in Example 25, and the exhaust inflow side cell was processed. I poured it in.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 4 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 5 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 6 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 7 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 8 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 9 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 10 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), P ₂ O ₃ glass powder as shown in Test Example 11 was used as an example of the ash capturing material. By the same treatment as in (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) For the honeycomb structure manufactured in the above (1) and (2), CaSO ₄ glass powder as shown in Test Example 12 was used as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) CaSO ₄ glass powder as shown in Test Example 13 was used as an example of the ash capturing material for the honeycomb structures manufactured in the above (1) and (2). By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) CaSO ₄ glass powder as shown in Test Example 14 was used as an example of the ash capturing material for the honeycomb structures manufactured in the above (1) and (2). By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) For the honeycomb structure manufactured in the above (1) and (2), CaSO ₄ glass powder as shown in Test Example 15 was used as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) For the honeycomb structure manufactured in the above (1) and (2), CaSO ₄ glass powder as shown in Test Example 16 was used as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in the above (1) and (2) was used with CaSO ₄ glass powder as shown in Test Example 17 as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) For the honeycomb structure manufactured in the above (1) and (2), CaSO ₄ glass powder as shown in Test Example 18 was used as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) For the honeycomb structure manufactured in the above (1) and (2), CaSO ₄ glass powder as shown in Test Example 19 was used as an example of the ash capturing material. By the same treatment as 3), an alumina slurry containing an ash trapping material was poured into the exhaust gas inflow side cell to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in the above (1) and (2) was used by using powder of flux A (sulfide-based flux) as shown in Test Example 20 as an example of the ash capturing material. By the same treatment as in Example 25 (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) The honeycomb structure manufactured in the above (1) and (2) was used by using powder of flux A (sulfide-based flux) as shown in Test Example 21 as an example of the ash capturing material. By the same treatment as in Example 25 (3), the alumina slurry containing the ash trapping material was poured into the cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), powder of flux B (chloride-containing system flux) as shown in Test Example 22 was used as an example of the ash capturing material. In the same manner as in Example 25 (3), an alumina slurry containing an ash trapping material was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in (1) and (2) above, powder of flux B (chloride-containing system flux) as shown in Test Example 23 is used as an example of the ash capturing material. In the same manner as in Example 25 (3), an alumina slurry containing an ash trapping material was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

(1) A honeycomb structure was manufactured in the same manner as in Example 25 (1) and (2).
(2) In the honeycomb structure manufactured in the above (1) and (2), powder of flux B (chloride-containing system flux) as shown in Test Example 24 was used as an example of the ash capturing material. In the same manner as in Example 25 (3), an alumina slurry containing an ash trapping material was poured into a cell on the exhaust gas inflow side to form a catalyst coat layer.

Comparative Example 2

(1) A honeycomb structure was produced in the same manner as in Example 25 (1) and (2), and no ash trapping material was dispersed in the catalyst coat layer.

(1) Ash trap to inorganic fiber, catalyst application step Alumina fiber (average fiber diameter: 5 μm, average fiber length: 0.3 mm), P ₂ O ₃ glass as shown in Test Example 1 is used as an ash capturing material. After impregnation in a slurry melted at 400 ° C. for 2 minutes, and further impregnation in an alumina slurry carrying Pt (Pt concentration: 5 wt%) for 2 minutes, heating to the slurry preparation temperature of each ash trapping material Thus, an alumina fiber containing an ash trapping material and having a catalyst attached thereto was prepared. As a result, the amount of Pt supported on the surface of the alumina particles was 0.24 g with respect to 10 g of alumina.

(2) Process for preparing papermaking slurry Next, the alumina fiber obtained in the process of (1) is dispersed at a rate of 10 g with respect to 1 liter of water. %, Acrylic latex was added as an organic binder at a rate of 3 wt%. Further, a small amount of aluminum sulfate as a coagulant and polyacrylamide as a flocculant were added in small amounts, and stirred sufficiently to prepare a papermaking slurry.

(3) Papermaking step The slurry obtained in the above (2) was made with a perforated mesh having a diameter of 143.8 mm in which 4.5 mm × 4.5 mm holes were formed almost entirely at intervals of 2 mm. The resulting product was dried at 150 ° C. to obtain a 1 mm thick paper sheet A1 having 4.5 mm × 4.5 mm holes formed on the entire surface at intervals of 2 mm.
Moreover, in order to obtain the sheet | seat for both ends, by using a mesh in which the hole of 4.5 mm x 4.5 mm is formed in the checkered pattern, papermaking and drying similarly, 4.5 mm x 4.5 mm Papermaking sheet B in which the holes were formed in a checkered pattern was obtained.

(4) Laminating Step A casing (cylindrical metal container) with a holding metal fitting attached to one side was erected so that the side with the metal fitting attached was down. And after laminating 3 paper sheets B, laminating 150 paper sheets A1, finally laminating 3 paper sheets, further pressing, and then installing the holding metal fitting on the other side, By fixing, a honeycomb structure made of a laminate having a length of 150 mm was obtained. The amount of Pt supported on this honeycomb structure was 5 g / l.
In this step, the sheets were laminated so that the cell holes overlapped.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that P ₂ O ₃ -based glass as shown in Test Example 2 was melted at 400 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that P ₂ O ₃ glass as shown in Test Example 3 was melted at 500 ° C. to make a slurry as an ash capturing material.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that P ₂ O ₃ -based glass as shown in Test Example 4 was melted at 600 ° C. to make a slurry as an ash capturing material.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that a P ₂ O ₃ glass as shown in Test Example 5 was melted at 600 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that P ₂ O ₃ glass as shown in Test Example 6 was melted at 400 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that P ₂ O ₃ glass as shown in Test Example 7 was melted at 500 ° C. to make a slurry as an ash capturing material.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that P ₂ O ₃ glass as shown in Test Example 8 was melted at 400 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that P ₂ O ₃ glass as shown in Test Example 9 was melted at 450 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that P ₂ O ₃ -based glass as shown in Test Example 10 was melted at 400 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that P ₂ O ₃ glass as shown in Test Example 11 was melted at 450 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that CaSO ₄ glass as shown in Test Example 12 was melted at 750 ° C. as an ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 13 was melted at 700 ° C. to make a slurry as an ash capturing material.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 14 was melted at 680 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 15 was melted at 770 ° C. to make a slurry as an ash capturing material.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 16 was melted at 730 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 17 was melted at 650 ° C. as a ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49 except that CaSO ₄ -based glass as shown in Test Example 18 was melted at 700 ° C. as an ash capturing material to form a slurry.

A laminated honeycomb structure was formed in the same manner as in Example 49, except that CaSO ₄ -based glass as shown in Test Example 19 was melted at 500 ° C. as an ash capturing material to form a slurry.

  A laminated honeycomb structure was formed in the same manner as in Example 49, except that flux A (sulfide-based flux) as shown in Test Example 20 was melted at 570 ° C. as a ash capturing material to form a slurry.

  A laminated honeycomb structure was formed in the same manner as in Example 49, except that flux A (sulfide-based flux) as shown in Test Example 21 was melted at 530 ° C. as a ash capturing material to form a slurry.

  A laminated honeycomb structure was formed in the same manner as in Example 49, except that flux B (chloride-containing flux) as shown in Test Example 22 was melted at 550 ° C. to form a slurry as an ash capturing material. .

  A laminated honeycomb structure was formed in the same manner as in Example 49, except that flux B (chloride containing flux) as shown in Test Example 23 was melted at 480 ° C. as a ash capturing material to form a slurry. .

  A laminated honeycomb structure was formed in the same manner as in Example 49, except that flux B (chloride-containing flux) as shown in Test Example 24 was melted at 480 ° C. as a ash capturing material to form a slurry. .

Comparative Example 3

  A honeycomb structure was manufactured in the same manner as in Example 49 except that the ash capturing material was not added in Example 49 (1).

The honeycomb structure manufactured by each of the above-described Examples 1 to 72 and Comparative Examples 1 to 3 was disposed in the exhaust passage of the engine as a particulate filter to form an exhaust gas purification device. The engine was operated at a rotational speed of 3000 min −1 and a torque of 50 Nm until 8 g / l of particulate was collected on the filter, and then a regeneration process for burning the particulate was performed 150 times. Thereafter, the filter was cut and the presence or absence of an ash trap was visually observed to examine the presence or absence of ash.
The manufacturing conditions and the presence or absence of ash absorption by the ash trap layer are shown in Tables 2 to 4 for each example, but the honeycomb structures of Examples 1 to 72 implemented under the conditions suitable for the present invention were collected by ash. It was confirmed that there was a difference.

  As described above, the filter according to the present invention can be used in fields such as an exhaust gas purification device for an internal combustion engine such as a diesel engine, an exhaust gas purification device in a factory or a garbage disposal site, and a heating device.

It is the perspective view which showed an example of the honey-comb filter concerning this invention. (A) is the perspective view which showed an example of the porous ceramic member which comprises the honeycomb filter shown in FIG. 1, (b) is the AA arrow of the porous ceramic member shown to (a). FIG. (A) is the perspective view which showed another example of the honey-comb filter concerning this invention, (b) is BB arrow sectional drawing of the honey-comb filter shown to (a). (A) is the perspective view which showed another example of the honey-comb filter concerning this invention, (b) is CC sectional view taken on the line of the honeycomb filter shown to (a). FIG. 5 is a diagram for explaining a part of a manufacturing process of the honeycomb filter shown in FIG. 4, (a) is a schematic diagram showing a paper sheet to be laminated, and (b) is a schematic diagram of a honeycomb filter formed by laminating paper sheets. FIG. It is a conceptual diagram of a catalyst coat layer (alumina film), (a) is a partially enlarged sectional view showing an example formed on the partition wall surface, and (b) is an example formed on each particle surface in the partition wall. It is sectional drawing which showed typically an example of the exhaust gas purification apparatus using the honey-comb filter concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Honeycomb structure 13, 14 Sealing material layer 15 Ceramic block 20 Porous ceramic member 21 Cell 21a Exhaust gas inflow side cell 21b Exhaust gas outflow side cell 22 Sealing material 23 Partition 30 Honeycomb structure 31 Cell 31a Exhaust gas inflow side cell 31b Exhaust gas outflow side cell 32 Sealing material 33 Partition wall 35 Ceramic block 40 Honeycomb structure 41 Cell 41a Exhaust gas inflow side cell 41b Exhaust gas outflow side cell 42 Sealing material 43 Partition wall 60 Honeycomb filter 100 Catalyst coat layer 600 Exhaust gas purification device 610 Heating means 620 Holding sealing material 630 Casing 640 Introduction pipe 650 Discharge pipe

Claims (14)

A filter for purifying particulate matter-containing exhaust gas discharged from an internal combustion engine, wherein ash trapping material particles are dispersed and contained in a catalyst coat layer formed on the inner partition wall surface of the filter. A filter characterized by The filter according to claim 1, wherein the ash capturing material particles are a glassy material or a low-melting-point inorganic compound-based flux material. The filter according to claim 1, wherein the ash capturing material particles are low-melting glass. 4. The catalyst coating layer according to claim 1, wherein the catalyst coating layer is provided on a partition wall surface of an exhaust gas inflow side cell of an integral-type or aggregate-type honeycomb structure or a laminated honeycomb structure. The filter according to item 1. The filter according to claim 1, wherein the catalyst coat layer is made of alumina supporting a catalyst. The catalyst coat layer is provided with a concentration gradient by increasing the content of ash trapping material particles dispersed and contained in the downstream side rather than the upstream side along the axial direction of the exhaust gas inflow side cell. The filter according to claim 1, wherein the filter is characterized by the following. A filter for purifying exhaust gas containing particulate matter discharged from an internal combustion engine, in a catalyst coat layer coated on the surface of each ceramic particle forming a partition wall separating each cell of the filter And a ash capturing material particle dispersed therein. The filter according to claim 7, wherein the ash capturing material particles are a glassy material or a low melting point inorganic compound-based flux. The filter according to claim 7 or 8, wherein the ash capturing material particles are low-melting glass. 8. The filter according to claim 7, wherein the catalyst coat layer is formed of an integral type, a collective type honeycomb structure, or a laminated type honeycomb structure. The filter according to claim 7, wherein the catalyst coat layer is made of alumina. The catalyst coat layer is provided with a concentration gradient by increasing the content of ash trapping material particles dispersed and contained in the downstream side rather than the upstream side along the axial direction of the exhaust gas inflow side cell. The filter according to any one of claims 7 to 12, characterized in that: An exhaust gas for an internal combustion engine, in which particulate matter contained in the exhaust gas is collected in an exhaust gas passage of the internal combustion engine, and a filter for reducing and removing nitrogen oxides and carbon monoxide is attached. In a purifying apparatus, the exhaust gas of an internal combustion engine using the filter according to any one of claims 1 to 6 or the filter according to any one of claims 7 to 12 as the filter. Purification equipment. In the method of collecting particulate matter in particulate matter containing exhaust gas discharged from an internal-combustion engine with a filter, in a catalyst coat layer provided in a cell of a filter given in any 1 paragraph of Claims 1-12 An exhaust gas purification method for an internal combustion engine, wherein the ash separated from the particulate matter is trapped by the ash trapping material particles, and the separated ash is trapped and removed in a filter.

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