JP5476011B2 - Exhaust gas purification device - Google Patents

Description

  The present invention relates to an exhaust gas purification device, and more particularly to an exhaust gas purification device including a honeycomb catalyst body in which a catalyst is supported on the surface of a partition wall in a cell and the amount of catalyst entering the partition wall is small.

  Particulate matter in exhaust gas discharged from internal combustion engines such as automobile engines, construction machinery engines, stationary engines for industrial machinery, and other combustion equipment must be removed from the exhaust gases in consideration of environmental impact. The nature is increasing. Therefore, a honeycomb filter made of ceramic is widely used as a filter (diesel particulate filter: DPF) for removing particulate matter. The DPF includes, for example, a predetermined cell (predetermined cell) that includes a porous partition wall that partitions and forms a plurality of cells serving as fluid flow paths, one end face of which is open and the other end face is plugged. In addition, a structure in which the remaining cells (residual cells) in which one end face is plugged and the other end face is opened is alternately used. In use, a fluid (exhaust gas) is caused to flow from the other end face where the remaining cells of the DPF are opened, and the inflowed exhaust gas is allowed to permeate through the partition wall and flow out into the predetermined cell as permeate. By letting the fluid flow out from the one end where the predetermined cell opens, the particulate matter in the exhaust gas is collected and removed by the partition walls.

  In general, the DPF is continuously used while being regenerated by burning and removing the collected particulate matter. The combustion reaction of particulate matter is usually promoted by a catalyst supported on DPF.

  Conventionally, the catalyst is supported on the DPF after forming plugged portions on both end faces of the honeycomb formed body (see, for example, Patent Document 1).

  Further, a honeycomb filter is disclosed in which two honeycomb formed bodies in which plugged portions are formed only on one end face are joined in series, and a catalyst is supported inside the cell (for example, see Patent Document 2).

JP-A-62-247111 JP 2004-251137 A

  The method described in Patent Document 1 has a problem that it is difficult to carry a catalyst because plugging is performed on both end faces of a ceramic honeycomb formed body. In addition, as a method for supporting the catalyst with both end faces plugged in this way, for example, the catalyst slurry is caused to flow from the other end face side while being sucked from one end face side of the honeycomb formed body. Thus, there is a method of supporting the catalyst on the honeycomb formed body. In this case, the catalyst slurry flows into the cell that opens to the other end face, and moves by the suction from one end face to the cell that passes through the porous partition wall and opens to the one end face. It flows in the cell opened to the end face and is discharged from one end face side. And when a catalyst slurry permeate | transmits a porous partition, a catalyst component is deposited in the pore formed in the partition surface and the partition, and a catalyst is carry | supported by the honeycomb molded object. However, in this method, since the catalyst slurry permeates through the partition walls by suction, a large amount of catalyst component is supported (deposited) in the pores of the partition walls. Most of the particulate matter burned and removed by the catalyst is deposited on the partition wall surface, so the catalyst present in the pores of the partition wall cannot contact the particulate matter and contributes almost to the combustion of the particulate matter. I can't. Therefore, when the catalyst is supported on the honeycomb formed body by this method, there is a problem that the contact efficiency between the catalyst and the particulate matter is lowered. Also, a method of sucking and removing excess catalyst slurry that has not been supported after flowing the catalyst slurry from one end face side with a thin tube inserted from the same end face side is conceivable. Not right.

  Patent Document 2 does not disclose a specific method for supporting a catalyst.

  The present invention has been made in view of such problems of the prior art, and the catalyst is supported on the surface of the partition walls in the cell and the amount of the catalyst entering the partition walls is small. At the same time, the durability is excellent. An exhaust gas purification apparatus including the honeycomb catalyst body is provided.

  The present invention provides the following exhaust gas purification apparatus.

[1] A honeycomb base material having a porous partition wall mainly composed of ceramic and forming a plurality of cells penetrating from one end surface to the other end surface and serving as a fluid flow path, and the one of the honeycomb base materials A honeycomb catalyst body having a first plugged portion disposed in an opening portion of a predetermined cell on the end surface of each of the cells, a catalyst supported on a partition wall surface in a remaining cell having both end portions open, and one end surface A honeycomb base material having a porous partition wall mainly composed of ceramic and forming a plurality of cells penetrating from the first end surface to the other end surface and serving as a fluid flow path, and a predetermined surface on the one end surface of the honeycomb base material A second one-side plugged honeycomb structure having a second plugged portion disposed in an opening of a cell, the honeycomb catalyst body, and the second one-side plugged honeycomb structure are accommodated. A can body and the honeycomb The material of the honeycomb base material of the catalyst body is different from the material of the honeycomb base material of the second one-side plugged honeycomb structure, and the second one-side plugged honeycomb structure has the second On the extension of the predetermined cell in which the plugged portions are formed, the remaining cells having both ends of the honeycomb catalyst body opened are disposed, and both end portions of the second one-side plugged honeycomb structure are disposed. The predetermined cell in which the first plugging portion of the Nicam catalyst body is formed on the extension of the remaining cells that are opened is disposed on the other end face of the honeycomb catalyst body, The honeycomb catalyst body and the second one-side plugged honeycomb structure are accommodated in the can body in a state where the end face of the second one-side plugged honeycomb structure is in contact with the second one-side plugged honeycomb structure . The length in the central axis direction of the one-side plugged honeycomb structure is 10 mm or more, and 40% or less of the total length in the central axis direction when the end face of the second one-side plugged honeycomb structure is brought into contact with the other end face of the honeycomb catalyst body, and the honeycomb catalyst body is The other end surface is a convex or concave curved surface, and the second one-side plugged honeycomb structure is in contact with the other end surface of the honeycomb catalyst body, and the other end surface of the honeycomb catalyst body is the other end surface. An exhaust gas purifying apparatus having a concave or convex curved surface complementary to a convex or concave curved surface of an end surface .

[ 2 ] The exhaust gas purification apparatus according to [1 ], wherein the second one-side plugged honeycomb structure further includes a catalyst supported on a partition wall surface in the remaining cell having both ends opened.

[ 3 ] In the honeycomb catalyst body, in the cross section orthogonal to the central axis, the area of the predetermined cell in which the first plugging portion is disposed is larger than the area of the remaining cell in which both end portions are open. The second one-side plugged honeycomb structure is small in cross section perpendicular to the central axis, and the area of the predetermined cell in which the first plugged portion is disposed is The exhaust gas purifying apparatus according to [1] or [ 2], which is larger than an area of the remaining cells that are opened.

[4] the curved end face formed in a convex shape of the honeycomb catalyst body or said second one side-plugged honeycomb structure, the height in the central axis direction according to a 1 to 10 mm [3] Exhaust gas purification device.

[ 5 ] Among the second plugged portions disposed in the second one-side plugged honeycomb structure, two or more second plugged portions are outside from the one end surface. A protruding plugged portion protruding into the remaining cell in which the protruding portions of the protruding plugged portion of the second one-side plugged honeycomb structure are open at both ends of the honeycomb catalyst body. The exhaust gas purification according to any one of [1] to [ 4 ], wherein the end face of the second one-side plugged honeycomb structure is brought into contact with the other end face of the honeycomb catalyst body in the inserted state. apparatus.

[ 6 ] The material of the honeycomb substrate of the honeycomb catalyst body is cordierite, and the material of the honeycomb substrate of the second one-side plugged honeycomb structure is silicon carbide or aluminum titanate [1] to [6]. [ 5 ] The exhaust gas purification apparatus according to any one of [ 5 ].

  In the exhaust gas purifying apparatus of the present invention, since the catalyst is supported on the cell in which both ends of the honeycomb catalyst body are opened, when the catalyst is supported, the catalyst slurry is simply passed through the cell without passing through the partition walls. Since the catalyst can be supported by the honeycomb catalyst body, the amount of catalyst deposited in the partition walls can be reduced.

It is a schematic diagram which shows the cross section parallel to the central axis of one Embodiment of the exhaust gas purification apparatus of this invention. It is a schematic diagram showing a cross section parallel to the central axis of a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting one embodiment of the exhaust gas purification apparatus of the present invention. 1 is a perspective view schematically showing a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting an embodiment of an exhaust gas purification apparatus of the present invention. FIG. 6 is a schematic view showing a cross section parallel to the central axis of a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting another embodiment of the exhaust gas purification apparatus of the present invention. FIG. 6 is a schematic view showing a cross section parallel to the central axis of a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. FIG. 6 is a plan view schematically showing one end face of a honeycomb catalyst body constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. FIG. 6 is a schematic view showing a cross section parallel to the central axis of a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. FIG. 6 is a schematic view showing a cross section parallel to the central axis of a honeycomb catalyst body and a second one-side plugged honeycomb structure constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. It is a schematic diagram which shows a part of manufacturing process of one Embodiment of the exhaust gas purification apparatus of this invention. It is a schematic diagram which shows a part of manufacturing process of one Embodiment of the exhaust gas purification apparatus of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the following embodiments, and is within the scope of the present invention. It should be understood that design changes, improvements, and the like can be made as appropriate based on the general knowledge of vendors.

(1) Exhaust gas purification device:
As shown in FIG. 1, an exhaust gas purification apparatus 100 of the present invention is a porous ceramic-based porous component that defines a plurality of cells 2 that penetrate from one end face 4 to the other end face 5 and serve as fluid flow paths. Honeycomb substrate 12 having a quality partition wall 3, first plugging portion 11 disposed in an opening portion of a predetermined cell 2a on one end face 4 of honeycomb substrate 12, and a remaining opening at both ends. The ceramic that forms the honeycomb catalyst body 20 having the catalyst 21 supported on the surface of the partition wall 3 in the cell 2b and a plurality of cells 32 that penetrate from one end face 34 to the other end face 35 and serve as fluid flow paths. A honeycomb substrate 42 having a porous partition wall 33 as a main component, and a second plugging portion 41 disposed in an opening of a predetermined cell 32a on one end face 34 of the honeycomb substrate 42. 2 one side plugging honey The arm structure 40, in which and a can body 50 for housing the honeycomb catalyst body 20 and the second one side-plugged honeycomb structure 40. And the remaining cell 2b which the both ends of the honeycomb catalyst body 20 open on the extension of the predetermined cell 32a in which the 2nd plugging part 41 was formed of the 2nd one-side plugged honeycomb structure 40 was formed. And the first plugged portion 11 of the Nicam catalyst body 20 is formed on the extension of the remaining cell 32b where both ends of the second one-side plugged honeycomb structure 40 are open. 2a is disposed, and the honeycomb catalyst body 20 is in contact with the end face (the other end face 35) of the second one-side plugged honeycomb structure 40 on the other end face 5 of the honeycomb catalyst body 20. 20 and the second one-side plugged honeycomb structure 40 are accommodated in a can body 50. Furthermore, the material of the honeycomb substrate 12 of the honeycomb catalyst body 20 and the material of the honeycomb substrate 42 of the second one-side plugged honeycomb structure 40 are different materials. FIG. 1 is a schematic diagram showing a cross section parallel to the central axis of an embodiment of the exhaust gas purifying apparatus of the present invention.

(1-1) honeycomb catalyst body;
In the honeycomb catalyst body 20, the honeycomb substrate 12 has a honeycomb shape having porous partition walls 3 mainly composed of ceramic that form a plurality of cells 2 serving as fluid flow paths. The average pore diameter of the partition walls 3 is preferably 5 to 30 μm, and more preferably 10 to 25 μm. If it is smaller than 5 μm, the pressure loss may increase even when the amount of particulate matter deposited is small, and if it is larger than 30 μm, the honeycomb catalyst body 20 may become brittle and likely to be lost, or the soot collection performance may be reduced. Sometimes. The average pore diameter of the partition walls 3 is a value measured with a mercury porosimeter.

  The porosity of the partition walls 3 is preferably 30 to 70%, and more preferably 40 to 60% in terms of ease of manufacture. If it is less than 30%, the pressure loss may increase, and if it is more than 70%, the honeycomb catalyst body 20 may become brittle and easily missing. The porosity of the partition walls 3 is a value measured with a mercury porosimeter.

  The thickness of the partition wall 3 is preferably 0.20 to 0.50 mm, and more preferably 0.25 to 0.45 mm in terms of ease of manufacture. If the thickness is less than 0.20 mm, the strength of the honeycomb catalyst body 20 may be reduced. If the thickness is more than 0.50 mm, the pressure loss when the exhaust gas passes through the cell may be increased. The thickness of the partition wall 3 is a value measured by a method of observing an axial cross section with a microscope.

The cell density of the cross section perpendicular to the central axis of the honeycomb catalyst body 20 (honeycomb substrate 12) is preferably 0.9 to 93 cells / cm ² (6 to 600 cpsi), and preferably 7.8 to 62 cells / cm. ² (50-400 cpsi) is more preferable. If it is less than 0.9 cell / cm ² , the strength of the honeycomb catalyst body 20 may be reduced, and if it is greater than 93 cell / cm ² , the pressure loss may be increased.

  The cell shape of the honeycomb catalyst body 20 is not particularly limited, but is preferably a polygon, such as a triangle, a quadrangle, a pentagon, a hexagon, an octagon, a circle, or an ellipse in a cross section perpendicular to the central axis. It may be a fixed form. A combination of a square and an octagon is also a preferred embodiment.

  The honeycomb substrate 12 (partition wall 3) is mainly composed of ceramic. Specifically, the partition 3 is made of silicon carbide, silicon-silicon carbide based composite material, cordierite, mullite, alumina, spinel, silicon carbide-cordierite based composite material, lithium aluminum silicate, and aluminum titanate. It is preferably at least one selected from the group. Among these, cordierite having a small thermal expansion coefficient and excellent thermal shock resistance is preferable. In addition, the phrase “having ceramic as a main component” means containing 90% by mass or more of the entire ceramic. In the exhaust gas purification apparatus of the present embodiment, the material of the honeycomb substrate 12 (partition 3) of the honeycomb catalyst body 20 and the material of the honeycomb substrate 42 (partition 33) of the second one-side plugged honeycomb structure 40 Are different materials. The material of the honeycomb substrate 12 of the honeycomb catalyst body 20 is preferably cordierite, and the material of the honeycomb substrate 42 of the second one-side plugged honeycomb structure 40 is preferably silicon carbide or aluminum titanate. By configuring in this way, there is an effect that the reproduction limit is improved as compared with the case where only cordierite is configured.

  The external shape of the honeycomb catalyst body 20 is not particularly limited, and examples thereof include a cylindrical shape such as a cylindrical shape, an elliptical cylindrical shape, and a rectangular cylindrical shape, and a cylindrical shape having an irregular bottom shape. Further, the size of the honeycomb catalyst body is not particularly limited, but the length in the central axis direction is preferably 40 to 500 mm. For example, when the honeycomb catalyst body 20 has a cylindrical outer shape, the bottom surface has a radius of preferably 50 to 500 mm.

  The material of the first plugging portion 11 disposed in the honeycomb catalyst body 20 is preferably the same material as the material of the honeycomb substrate 12 (partition wall 3) constituting the honeycomb catalyst body 20. Thereby, the 1st plugging part 11 comes to couple | bond with the partition 3 firmly at the time of baking.

  The first plugged portions 11 disposed in the honeycomb catalyst body 20 preferably have an average pore diameter of 0.1 to 20 μm, and more preferably 1 to 15 μm. If the average pore diameter is larger than 20 μm, the particulate matter may enter the pores and close the pores, and the pressure loss may increase. When the average pore diameter of the first plugged portion 11 is smaller than 0.1 μm, the exhaust gas hardly passes and the pressure loss may increase. The average pore diameter of the first plugged portion 11 is a value measured with a mercury porosimeter.

  The porosity of the first plugged portion 11 is preferably 30 to 60%, and more preferably 35 to 55%. If it is less than 30%, the pressure loss increases and the amount of exhaust gas treated may be reduced. If it is more than 60%, the first plugged portion 11 becomes brittle and easily lost, and the strength decreases, so the DPF. Cracks are likely to occur due to thermal stress generated during reproduction. The porosity of the first plugged portion 11 is a value measured with a mercury porosimeter.

  The length (plugging depth) of the first plugged portion 11 in the cell extending direction is preferably 1 to 15 mm, and more preferably 1 to 10 mm. If it is shorter than 1 mm (shallow), the strength may decrease. If it is longer (deep) than 15 mm, the filtration area of the honeycomb catalyst body (area of partition walls capable of collecting particulate matter) may be small.

  In the honeycomb catalyst body 20, predetermined cells 2a in which the first plugging portions 11 are formed at one end and the remaining cells 2b in which both ends are opened are alternately arranged, and one end face However, it is preferable that a checkered pattern is formed by the plugged cells and the non-plugged cells.

  Further, the honeycomb catalyst body 20 may have an outer peripheral wall located at the outermost periphery thereof. The outer peripheral wall is preferably a molded integral wall that is integrally formed with the porous base material during molding. It is also a preferred embodiment that it is a cement-coated wall that forms the wall.

Examples of the catalyst 21 include an oxidation catalyst for purifying diesel engine exhaust gas. The oxidation catalyst for purifying diesel engine exhaust gas contains a noble metal. The noble metal is preferably one or more selected from the group consisting of Pt, Rh, and Pd. The total amount of noble metals is preferably 0.17 to 7.07 g per liter of honeycomb catalyst body volume. The NO _X selective reduction SCR catalyst and the NO _X storage catalyst can be used in combination.

Examples of the SCR catalyst for NO _X selective reduction include those containing at least one selected from the group consisting of metal-substituted zeolite, vanadium, titania, tungsten oxide, silver, and alumina. Examples of the NO _X storage catalyst include alkali metals and / or alkaline earth metals. Examples of the alkali metal include K, Na, Li and the like. Ca can be mentioned as an alkaline earth metal. The total amount of K, Na, Li, and Ca is preferably 5 g or more per liter of the volume of the honeycomb catalyst body.

  Further, the amount of catalyst supported in the pores of the partition walls is preferably 0 to 35% by mass, and more preferably 0 to 25% by mass based on the total amount of catalyst supported on the honeycomb catalyst body. When the amount is more than 35% by mass, the catalyst in the pores of the partition wall hardly comes into contact with the particulate matter, and the contact efficiency between the particulate matter collected from the exhaust gas and the entire catalyst may be lowered. The smaller the amount of the catalyst supported in the pores of the partition walls, the better the contact efficiency between the particulate matter and the whole catalyst. However, in reality, the lower limit is 5% by mass.

(1-2) Second one-side plugged honeycomb structure;
In the second one-side plugged honeycomb structure 40, the honeycomb substrate 42 has a honeycomb shape having porous partition walls 33 mainly composed of ceramic, which partition and form a plurality of cells 32 serving as fluid flow paths. is there. The average pore diameter of the partition walls 33 is preferably 5 to 30 μm, and more preferably 10 to 25 μm. If it is smaller than 5 μm, the pressure loss may increase even when the amount of particulate matter deposited is small, and if it is larger than 30 μm, the second one-side plugged honeycomb structure 40 may become brittle and easily missing. Soot collection performance may decrease. The average pore diameter of the partition wall 33 is a value measured with a mercury porosimeter.

  The porosity of the partition wall 33 is preferably 30 to 70%, and more preferably 40 to 60% in terms of ease of manufacture. If it is less than 30%, the pressure loss may increase, and if it is more than 70%, the second one-side plugged honeycomb structure 40 may become brittle and easily missing. The porosity of the partition wall 33 is a value measured by a mercury porosimeter.

  The thickness of the partition wall 33 is preferably 0.20 to 0.50 mm, and more preferably 0.25 to 0.45 mm from the viewpoint of ease of manufacture. If it is thinner than 0.20 mm, the strength of the second one-side plugged honeycomb structure 40 may be reduced, and if it is thicker than 0.50 mm, the pressure loss when the exhaust gas passes through the cell may increase. is there. The thickness of the partition wall 33 is a value measured by a method of observing an axial cross section with a microscope.

The cell density of the cross section perpendicular to the central axis of the second one-side plugged honeycomb structure 40 (honeycomb substrate 42) is preferably 0.9 to 93 cells / cm ² (6 to 600 cpsi), More preferably, it is 8 to 62 cells / cm ² (50 to 400 cpsi). If it is less than 0.9 cells / cm ² , the strength of the second one-side plugged honeycomb structure 40 may be reduced, and if it is more than 93 cells / cm ² , pressure loss may be increased.

  The cell shape of the second one-side plugged honeycomb structure 40 is not particularly limited. However, in the cross section orthogonal to the central axis, the cell shape is triangular, quadrilateral, pentagonal, hexagonal, octagonal or other polygonal, circular, or elliptical. It is preferable that it may be irregular. A combination of a square and an octagon is also a preferred embodiment.

  The honeycomb substrate 42 (partition wall 33) is mainly composed of ceramic. Specific examples of the material of the honeycomb substrate 42 (partition wall 33) include silicon carbide, silicon-silicon carbide based composite material, cordierite, mullite, alumina, spinel, silicon carbide-cordierite based composite material, and lithium aluminum silicate. And at least one selected from the group consisting of aluminum titanates. Among these, silicon carbide or aluminum titanate is preferable. By using silicon carbide or aluminum titanate, there is an advantage that the regeneration limit is improved. As described above, the material of the honeycomb substrate 12 of the honeycomb catalyst body 20 is cordierite, and the material of the honeycomb substrate 42 of the second one-side plugged honeycomb structure 40 is silicon carbide or aluminum titanate. Is preferred.

  The external shape of the second one-side plugged honeycomb structure 40 is not particularly limited, and examples thereof include a cylindrical shape of a bottom surface such as a cylindrical shape, an elliptical cylindrical shape, and a rectangular cylindrical shape, and a cylindrical shape having an indefinite shape on the bottom surface. Can do. Further, the size of the second one-side plugged honeycomb structure 40 is not particularly limited, but the length in the central axis direction is preferably 5 to 300 mm. Further, for example, when the outer shape of the second one-side plugged honeycomb structure 40 is a cylindrical shape, the radius of the bottom surface is preferably 50 to 500 mm. Further, the length of the second one-side plugged honeycomb structure 40 in the central axis direction is 10 mm or more, and the other end face 5 of the honeycomb catalyst body 20 is in contact with the end face of the second one-side plugged honeycomb structure 40. It is preferably 40% or less with respect to the total length in the central axis direction when contacted (the total length in the central axis direction of the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40). . By setting the length of the second one-side plugged honeycomb structure 40 in the central axis direction to such a length, there is an advantage that canning is facilitated. The cross-sectional shape perpendicular to the central axis of the second one-side plugged honeycomb structure 40 is preferably the same as the cross-sectional shape perpendicular to the central axis of the honeycomb substrate 12 of the honeycomb catalyst body 20.

  The material of the second plugged portion 41 constituting the second one-side plugged honeycomb structure 40 is the same as the material of the honeycomb substrate 42 constituting the second one-side plugged honeycomb structure 40. It is preferable. Accordingly, the second plugging portion 41 is firmly bonded to the partition wall 33 during firing.

  In the second one-side plugged honeycomb structure 40, the second plugged portion 41 preferably has an average pore diameter of 0.1 to 20 μm, and more preferably 1 to 15 μm. If the average pore diameter is larger than 20 μm, the particulate matter may enter the pores and close the pores, and the pressure loss may increase. If the average pore diameter of the second plugged portion 41 is smaller than 0.1 μm, the exhaust gas hardly passes and the pressure loss may increase. The average pore diameter of the second plugged portion 41 is a value measured with a mercury porosimeter.

  The porosity of the second plugged portion 41 is preferably 30 to 60%, and more preferably 35 to 55%. If it is less than 30%, the pressure loss increases and the amount of exhaust gas treated may be reduced. If it is more than 60%, the second plugging portion 41 becomes brittle and easily lost, and the strength decreases, so the DPF. There is a risk that cracks are likely to occur due to thermal stress generated during reproduction. The porosity of the second plugging portion 41 is a value measured with a mercury porosimeter.

  The length (plugging depth) of the second plugged portion 41 in the cell extending direction is preferably 1 to 15 mm, and more preferably 1 to 10 mm. If it is shorter than 1 mm (shallow), the strength may decrease. When it is longer (deep) than 15 mm, the filtration area of the filter may be small.

  In the second one-side plugged honeycomb structure 40, predetermined cells 2a in which the second plugged portions 41 are formed at one end and the remaining cells 32b in which both ends are opened alternately It is preferable that one end surface 34 is formed by a checkered pattern formed by plugged cells and non-plugged cells.

  It is preferable that the second one-side plugged honeycomb structure 40 further includes a catalyst supported on the surface of the partition wall 33 in the remaining cell 32b having both ends opened. Thereby, since the carrying area increases, the exhaust gas purification performance can be improved. The amount per volume of the catalyst to be supported and the one-side plugged honeycomb structure of the catalyst to be supported may be substantially the same as or different from that of the honeycomb catalyst body 20.

  Further, the second one-side plugged honeycomb structure 40 may have an outer peripheral wall located at the outermost periphery thereof. The outer peripheral wall is preferably a molded integral wall that is integrally formed with the porous base material during molding. It is also a preferred embodiment that it is a cement-coated wall that forms the wall.

(1-3) Exhaust gas purification device;
As shown in FIG. 1, one embodiment of the exhaust gas purifying apparatus of the present invention is the “predetermined cell 32 a in which the second plugging portion 41 is formed” of the second one-side plugged honeycomb structure 40. "Remaining cells 2b open at both ends" of the honeycomb catalyst body 20 are disposed on the extension of "and the remaining cells 32b open at both ends" of the second one-side plugged honeycomb structure 40. On the other end face 5 of the honeycomb catalyst body 20 so that the “predetermined cells 2a in which the first plugging portions 11 are formed” of the honeycomb catalyst body 20 are disposed on the extension of the second one side. By bringing the end face (the other end face 35) of the plugged honeycomb structure 40 into contact, the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 as shown in FIGS. 2A and 2B can be obtained. A series-type honeycomb filter 101 connected in series is formed, Column type honeycomb filter 101 is housed in the can body 50. The honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 may be bonded by an adhesive or the like, or may be accommodated in the can without being bonded by the adhesive or the like.

  As shown in FIG. 1, in the exhaust gas purification apparatus of the present embodiment, one end surface 4 on which the first plugging portion 11 of the honeycomb catalyst body 20 is disposed is a can into which the exhaust gas G of the can body 50 flows. One end face 34 disposed on the body inlet 52 side and provided with the second plugging portion 41 of the second one-side plugged honeycomb structure 40 is a can body from which the exhaust gas G of the can body 50 flows out. It is preferable to arrange on the outlet 53 side. Thereby, the particulate matter contained in the exhaust gas G can be deposited in the remaining cells 2b opened to the one end face 4 side of the honeycomb catalyst 20. The catalyst 21 supported in the remaining cells 2b of the honeycomb catalyst 20 can promote combustion removal of the accumulated particulate matter.

  In the exhaust gas purifying apparatus of the present embodiment, as shown in FIG. 1, the in-line honeycomb filter 101 is disposed in the can body 50 with the outer periphery covered with the cushion material 51. The cushion material 51 prevents the in-line honeycomb filter 101 from being damaged. The series-type honeycomb filter 101 is preferably housed in the can body 50 with pressure applied from the outside via the cushion material 51. Thereby, it is possible to prevent the series-type honeycomb filter 101 from moving in the can body 50, and the series-type honeycomb filter 101 can be stabilized in the can body 50. As the cushion material 51, a ceramic fiber mat or the like can be used, and it may be stored by a known method (for example, JP-A-07-77036).

  The can 50 is not particularly limited, and cans that are normally used for housing a ceramic honeycomb filter for purifying exhaust gas such as automobile exhaust gas can be used. Examples of the material of the can body 50 include stainless steel. The size of the can body 50 is preferably a size that allows the in-line honeycomb filter 101 to be press-fitted with the cushion material 51 wound around.

(1-4) Another embodiment of the exhaust gas purification device;
Another embodiment of the exhaust gas purifying apparatus of the present invention is the same as the embodiment of the exhaust gas purifying apparatus of the present invention, in which the in-line honeycomb filter 101 is connected to the other end face 5 of the honeycomb catalyst body 20 as shown in FIG. Further, one end face 34 of the second one-side plugged honeycomb structure 40 is brought into contact with the second one-side plugged honeycomb structure 40. This makes it possible to change the temperature distribution of the series-type honeycomb filter at the time of regeneration, or to prevent gaps between the partition walls even if misalignment occurs in contact between the honeycomb catalyst body and the one-side plugged honeycomb structure. There is an advantage such as. FIG. 3 shows a “honeycomb catalyst body 20 and a second one-side plugged honeycomb structure 40” (series-type honeycomb filter 101) constituting another embodiment of the exhaust gas purification apparatus of the present invention, which is parallel to the central axis. It is a schematic diagram which shows a cross section.

(1-5) Still another embodiment of the exhaust gas purification device;
In another embodiment of the exhaust gas purifying apparatus of the present invention, as shown in FIGS. 4A and 4B, the honeycomb catalyst body 20 is provided with the first plugging portion 11 in a cross section perpendicular to the central axis. The area of the predetermined cell 2a is smaller than the area of the remaining cell 2b open at both ends. Then, in the cross section perpendicular to the central axis of the second one-side plugged honeycomb structure 40, the area of the predetermined cell 32 a in which the second plugged portion 41 is disposed is the remaining opening at both ends. It is larger than the area of the cell 32b. As a result, when the particulate matter is deposited in the remaining cells 2b open at both ends, the area of the partition wall on which the particulate matter is deposited is increased, and a large amount of particulate matter can be collected. An increase in pressure loss due to collection of particulate matter can be suppressed. And purification efficiency can be improved. The area ratio between the large area cell and the small area cell is preferably 1.1 to 3 times as large as the large area cell. The exhaust gas purification apparatus of the present embodiment is preferably the same as that of one embodiment or other embodiments of the exhaust gas purification apparatus of the present invention described above, except for the configuration described above. FIG. 4A is parallel to the central axis of “honeycomb catalyst body 20 and second one-side plugged honeycomb structure 40” (series-type honeycomb filter 101) constituting still another embodiment of the exhaust gas purification apparatus of the present invention. It is a schematic diagram which shows an appropriate cross section. FIG. 4B is a plan view schematically showing one end face of a honeycomb catalyst body constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. The honeycomb catalyst body 20 in FIG. 4A corresponds to the AA ′ cross section in FIG. 4B.

(1-6) Still another embodiment of the exhaust gas purification device;
In another embodiment of the exhaust gas purifying apparatus of the present invention, as shown in FIG. 5, the honeycomb catalyst body 20 has a curved surface in which the other end surface 5 is convex or concave, and the second one-side plugged honeycomb structure. The end face (one end face 34) on the side where the body 40 contacts the other end face 5 of the honeycomb catalyst body 20 is complementary to the convex or concave curved surface of the other end face 5 of the honeycomb catalyst body 20. It is a concave or convex curved surface. Then, the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are the other end face 5 which is a convex or concave curved surface of the honeycomb catalyst body 20, and the second one-side plugged honeycomb structure. The end surface (one end surface 34) which is 40 concave or convex curved surfaces is accommodated in the can body in a state of being in contact with each other so as to be in close contact with each other. Except for the above configuration, it is preferable to be the same as the one embodiment, the other embodiment, or the other embodiment of the exhaust gas purification apparatus of the present invention described above. With this configuration, the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 can be easily positioned in the can body 50, and can be prevented from shifting in the can body during use. Can do. FIG. 5 is parallel to the central axis of “honeycomb catalyst body 20 and second one-side plugged honeycomb structure 40” (series honeycomb filter 101) constituting still another embodiment of the exhaust gas purifying apparatus of the present invention. It is a schematic diagram which shows an appropriate cross section. In FIG. 5, the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are illustrated apart from each other for convenience. The honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are in contact with each other.

  In the second one-side plugged honeycomb structure 40, the end surface that is a concave or convex curved surface may be one end surface 34 on which the second plugging portion 41 is disposed, or the plugging may be performed. The other end surface 35 in which no part is formed may be used. Further, in the honeycomb catalyst body 20 shown in FIG. 5, the other end face 5 is a convex curved surface, but this may be a concave curved surface. In that case, it is preferable that the end surface of the second one-side plugged honeycomb structure 40 that contacts the other end surface 5 of the honeycomb catalyst body 20 has a convex curved surface.

  The method for forming the convex or concave end faces of the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 is not particularly limited. However, the honeycomb molded body (first honeycomb molded body, The end surface of the honeycomb formed body 2 is preferably cut by grinding. Moreover, you may cut and form the end surface of the honeycomb molded body after baking by grinding. In addition, after the extrusion molding, the end surface of the honeycomb molded body (first honeycomb molded body, second honeycomb molded body) may be formed into a convex shape or a concave shape by embossing before drying.

  The height H of the convex curved surface of the honeycomb catalyst body 20 is preferably 0.5 to 20 mm, and more preferably 1 to 10 mm. When the other end face 5 of the honeycomb catalyst body 20 is concave, the depth of the concave curved surface is preferably in the same range as the height H of the convex curved surface. When the height H is lower than 0.5 mm, the effect of stably storing the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 in the can may be reduced. When the height H is higher than 20 mm, the time required for processing becomes long, and the production efficiency may be lowered.

(1-7) Still another embodiment of the exhaust gas purification device;
Still another embodiment of the exhaust gas purifying apparatus of the present invention includes two of the second plugging portions 41 arranged in the second one-side plugged honeycomb structure 40 as shown in FIG. The second plugged portion 41 described above is a protruding plugged portion 41a protruding outward from one end surface 34, and the protruding plugged portion 41a of the second one-side plugged honeycomb structure 40 protrudes. The end face of the second one-side plugged honeycomb structure 40 is formed on the other end face 5 of the honeycomb catalyst body 20 in a state where the portion 41b is inserted into the remaining cell 2b where both ends of the honeycomb catalyst body 20 are open. (One end face 34) is abutted. This facilitates the positioning of the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 in the can body 50, and can prevent displacement in the can body during use. Except for the above configuration, it is preferable to be the same as the one embodiment, the other embodiment, or the other embodiment of the exhaust gas purification apparatus of the present invention described above. FIG. 6 is parallel to the central axis of “honeycomb catalyst body 20 and second one-side plugged honeycomb structure 40” (series-type honeycomb filter 101) constituting still another embodiment of the exhaust gas purification apparatus of the present invention. It is a schematic diagram which shows an appropriate cross section. In FIG. 6, the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are illustrated apart from each other for convenience. The honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are in contact with each other.

  There are two or more second plugged portions 41 (projected plugged portions 41a) protruding outward from one end face 34 of the second one-side plugged honeycomb structure 40, and 2 to 4 are plugged. preferable. If there are too many projecting plugged portions 41a, pressure loss may increase. Further, the protruding plugging portion 41a may be formed by projecting the plugging material at the time of filling, or by producing a particulate plugging material and using the particulate plugging material for the cell. You may insert in an opening part. The shape of the protruding plugging portion 41a is not particularly limited, and the protruding portion 41b may be any shape such as an arc shape, a polygon such as a triangle or a quadrangle, and a shape where the tip is recessed in a V shape or a U shape. The part to be disposed may be anywhere on the end face, but it is desirable to dispose the parts so as to be substantially even on a concentric circle.

(2) Manufacturing method of exhaust gas purification device:
Next, the manufacturing method of one Embodiment of the exhaust gas purification apparatus of this invention is demonstrated. Although the manufacturing method of one Embodiment of the exhaust gas purification apparatus of this invention is not specifically limited, For example, the following method can be mentioned. A honeycomb base material having a porous partition wall mainly composed of ceramic that forms a plurality of cells that penetrate from one end face to the other end face and serves as a fluid flow path, and a predetermined end face on one end face of the honeycomb base material The first plugged portion is not formed from one end face side of the first one-side plugged honeycomb structure provided with the first plugged portion disposed in the opening of the cell. A honeycomb catalyst body forming step in which the catalyst slurry is caused to flow into the remaining cells having both ends opened, and the catalyst is applied to the partition wall surfaces in the remaining cells having both ends open to form a honeycomb catalyst body; A honeycomb substrate having a porous partition wall mainly composed of ceramic, which defines a plurality of cells that penetrate from one end surface to the other end surface and serve as a fluid flow path, and a predetermined surface on one end surface of the honeycomb substrate. A second eye disposed in the opening of the cell In the second one-side plugged honeycomb structure provided with a stopper, on the extension of a predetermined cell in which the second plugged portion is formed, there are remaining cells that are open at both ends of the honeycomb catalyst body. And a predetermined cell in which the first plugging portion of the honeycomb catalyst body is formed on the extension of the remaining cell that is open at both ends of the second one-side plugged honeycomb structure. Thus, the honeycomb catalyst body and the second one-side plugged honeycomb structure in a state where the end face (the other end face) of the second one-side plugged honeycomb structure is in contact with the other end face of the honeycomb catalyst body. And a step of storing the body in a can body (canning step). Hereinafter, each step will be described.

(2-1) honeycomb catalyst body forming step;
In the honeycomb catalyst body forming step, as shown in FIG. 7, the first plugged portion 11 is not formed from one end face 4 side of the first one-side plugged honeycomb structure 10, and both ends are opened. The catalyst slurry is caused to flow into the remaining cells 2b to be applied, and the catalyst is applied to the surfaces of the partition walls 3 in the remaining cells 2b having both ends opened to form the honeycomb catalyst body 20. Thus, from one end face 4 side of the first one-side plugged honeycomb structure 10, “cells in which both ends are opened without forming the first plugged portions 11 (residual cells 2 b)”. The catalyst slurry is caused to flow into the inside, and the catalyst is applied to the surface of the partition walls 3 in the remaining cells 2b that are open at both ends. Therefore, the catalyst slurry is prevented from passing through the porous partition walls 3, Most can be deposited on the surface of the partition 3 in the cell (the remaining cell 2b). Since both ends of the cell for coating the catalyst (remaining cell 2b) are open, the catalyst slurry can flow so as to pass only through the cell (remaining cell 2b) where both ends are open. The catalyst slurry can be prevented from penetrating the partition walls 3 and entering the cells (predetermined cells 2a) in which the first plugging portions 11 are formed. When the catalyst slurry permeates the partition walls 3, the catalyst is deposited in the pores of the partition walls 3. Therefore, according to the method for manufacturing the exhaust gas purification apparatus of the present embodiment, which can prevent the catalyst from permeating the partition walls 3, It is possible to prevent the catalyst from being deposited in the pores of the partition walls 3. According to the exhaust gas purification apparatus manufactured by the method for manufacturing the exhaust gas purification apparatus of the present embodiment, it is possible to prevent the catalyst from being deposited in the pores of the partition walls 3 and to carry the catalyst on the surfaces of the partition walls 3. When the collected particulate matter is removed by combustion, the contact efficiency between the catalyst and the particulate matter is high, and the particulate matter can be burned efficiently.

  The first one-side plugged honeycomb structure 10 used in the honeycomb catalyst body forming step is preferably manufactured as follows. That is, as shown in FIG. 7, a first honeycomb formed body 1 having partition walls 3 defining a plurality of cells 2 that penetrate from one end face 4 to the other end face 5 and serve as fluid flow paths is formed by extrusion molding. The first honeycomb formed and filled with the first plugging material in the opening portion of the predetermined cell 2a on one end face 4 of the first honeycomb molded body 1 is filled. It is preferable to fire the molded body 1 to produce the first one-side plugged honeycomb structure 10 having the first plugged portions 11 on one end face 4. After the first honeycomb formed body 1 is fired, the first plugging member may be filled and further fired.

  The method for extruding the first honeycomb formed body 1 is not particularly limited. For example, it is preferable to first knead the forming raw material to form a clay and shape the obtained clay into a honeycomb shape. There is no restriction | limiting in particular as a method of kneading | mixing a shaping | molding raw material and forming a clay, For example, the method of using a kneader, a vacuum clay kneader, etc. can be mentioned. Then, the kneaded material is extruded to form a honeycomb formed body. Extrusion molding is preferably performed using a die having a desired cell shape, partition wall thickness, and cell density. As the material of the die, a cemented carbide which does not easily wear is preferable.

  The forming raw material is preferably a ceramic raw material added with a dispersion medium and an additive, and examples of the additive include an organic binder, a pore former, and a surfactant. Examples of the dispersion medium include water.

  The ceramic raw material is selected from the group consisting of silicon carbide, silicon-silicon carbide based composite material, cordierite forming raw material, mullite, alumina, spinel, silicon carbide-cordierite based composite material, lithium aluminum silicate, and aluminum titanate. It is preferable that there is at least one. Among these, a cordierite-forming raw material having a small thermal expansion coefficient and excellent thermal shock resistance is preferable. The content of the ceramic raw material is preferably 30 to 95% by mass with respect to the entire forming raw material. The ceramic raw material is selected so that the material of the honeycomb substrate 12 of the honeycomb catalyst body 20 and the material of the honeycomb substrate 42 of the second one-side plugged honeycomb structure 40 are different. The ceramic raw material is selected so that the material of the honeycomb substrate 12 of the honeycomb catalyst body 20 is cordierite and the material of the honeycomb substrate 42 of the second one-side plugged honeycomb structure 40 is silicon carbide or aluminum titanate. It is preferable to do.

  Examples of the organic binder include methyl cellulose, hydroxypropoxyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol. Among these, it is preferable to use methyl cellulose and hydroxypropoxyl cellulose in combination. The binder content is preferably 2 to 20% by mass with respect to the entire forming raw material.

  The pore former is not particularly limited as long as it becomes pores after firing, and examples thereof include starch, foamed resin, water absorbent resin, silica gel and the like. The pore former content is preferably 0 to 20% by mass with respect to the entire forming raw material.

  As the surfactant, ethylene glycol, dextrin, fatty acid soap, polyalcohol and the like can be used. These may be used individually by 1 type, and may be used in combination of 2 or more type. The content of the surfactant is preferably 0 to 5% by mass with respect to the entire forming raw material.

  It is preferable that content of a dispersion medium is 5-50 mass% with respect to the whole shaping | molding raw material.

  By adjusting the particle size and blending amount of the ceramic raw material (aggregate particles) used and the particle size and blending amount of the pore former to be added, a porous substrate having a desired porosity and average pore size is obtained. Can do.

  Next, the obtained first honeycomb formed body 1 may be dried. The drying method is not particularly limited, and examples thereof include hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, freeze drying and the like. Among them, dielectric drying, microwave drying or It is preferable to perform hot air drying alone or in combination. The drying conditions are preferably a drying temperature of 30 to 150 ° C. and a drying time of 1 minute to 2 hours.

  Next, the first plugging material is filled into the opening portions of the predetermined cells 2 a on one end face 4 of the obtained first honeycomb formed body 1. When the first plugging material is filled in the opening of the predetermined cell 2a, for example, first, the opening of the remaining cell 2b is plugged into one end face 4 of the first honeycomb formed body 1. A mask is applied in a checkered pattern. The method of applying the mask does not have to be a checkered pattern. And the slurry-like 1st plugging material containing a ceramic raw material, water or alcohol, and an organic binder is stored in the storage container. The ceramic raw material is preferably the same as the ceramic raw material used for forming the first honeycomb formed body 1. The ceramic raw material is preferably 70 to 90% by mass of the entire first plugging material. Moreover, it is preferable that water or alcohol is 10-30 mass% of the whole 1st plugging material, and an organic binder is 0.1-2.0 mass% of the whole 1st plugging material. Preferably there is. Examples of the organic binder include hydroxypropoxyl methylcellulose and methylcellulose. Then, one end face 2a side on which the mask is applied is immersed in a storage container, and the “opening portion of the predetermined cell 2a” which is not provided with the mask is filled with the first plugging material. It is preferable that the viscosity of the first plugging material is 600 to 1200 Pa · s. In addition, the viscosity of the plugging material is a value measured at a rotation speed of 30 rpm with a rotary viscometer at a temperature of 30 ° C.

  Next, it is preferable to dry the first honeycomb formed body 1 in which the “opening portion of the predetermined cell” on one end face 4 is filled with the first plugging material. The drying method is not particularly limited, and for example, a known drying method such as hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, freeze drying, or the like can be used. Among these, a drying method that combines hot air drying and microwave drying or dielectric drying is preferable in that the entire first honeycomb formed body 1 can be quickly and uniformly dried.

  Next, the first honeycomb formed body 1 in which the opening portions of the predetermined cells 2a on one end face 4 are filled with the first plugging material is preferably calcined before firing. The “calcination” means an operation for burning and removing organic substances (organic binder, dispersant, pore former, etc.) in the honeycomb formed body. Generally, the combustion temperature of the organic binder is about 100 to 300 ° C., and the combustion temperature of the pore former is about 200 to 800 ° C. Therefore, the calcining temperature may be about 200 to 1000 ° C. Although there is no restriction | limiting in particular as a calcination time, Usually, it is about 10 to 100 hours.

  Next, the first honeycomb molded body 1 filled with the first plugging material is fired, and the first one-side plugged honeycomb structure having the first plugged portion 11 on one end face 4 is fired. It is preferable to produce the body 10. In the present invention, “fired” means an operation for sintering and densifying the honeycomb formed body and the plugging material to ensure a predetermined strength. The firing temperature can be appropriately determined depending on the material of the first honeycomb formed body 1 and the material of the first plugging portions. For example, when the material of the first honeycomb formed body 1 and the material of the first plugging portions are cordierite, the firing temperature is preferably 1380 to 1450 ° C, and more preferably 1400 to 1440 ° C. Thereby, the 1st plugging part can be firmly fused to the partition of a honeycomb fabrication object. The firing time is preferably about 3 to 10 hours. When the material of the first honeycomb formed body 1 and the material of the first plugging portion are silicon carbide, the firing temperature is preferably 1200 to 1600 ° C, and more preferably 1300 to 1500 ° C. Thereby, the 1st plugging part can be firmly fused to the partition of a honeycomb fabrication object. Moreover, it is preferable that baking time shall be about 1 to 20 hours.

  After the first one-side plugged honeycomb structure 10 is manufactured by the above method, the first plugged portion 11 is not formed from one end face 4 side of the first one-side plugged honeycomb structure 10. The catalyst slurry is allowed to flow into the remaining cells 2b having both ends opened, and the catalyst 21 is applied to the surfaces of the partition walls 3 in the remaining cells 2b having both ends opened to form the honeycomb catalyst body 20. Since the catalyst slurry is allowed to permeate the cells having both ends opened, the catalyst slurry does not permeate the partition walls, and thus the honeycomb catalyst body 20 has a small amount of catalyst that has entered the pores formed in the partition walls. .

  The method for applying (supporting) the catalyst is not particularly limited, and the catalyst can be applied (supported) by a known method. For example, first, a catalyst slurry containing a predetermined catalyst is prepared. When the catalyst slurry is allowed to flow into the remaining cells 2b that are open at both ends, it is preferable to use dipping or suction methods. The catalyst slurry is preferably applied to the entire surface of the partition walls in the cell.

  After flowing the catalyst slurry into the cell, it is preferable to blow off the excess slurry with compressed air. Thereafter, the catalyst is preferably dried and baked to obtain a honeycomb catalyst body in which the catalyst is coated (supported) on the surface of the partition walls in the cell. The drying conditions are preferably 80 to 150 ° C. and 1 to 6 hours. Moreover, it is preferable that baking conditions shall be 450-700 degreeC and 0.5 to 6 hours.

  Moreover, alumina etc. are mentioned as components other than the catalyst contained in a catalyst slurry.

(2-2) canning step;
In the canning step, as shown in FIG. 1, the honeycomb catalyst body is formed on the extension of the “predetermined cells 32a in which the second plugging portions 41 are formed” of the second one-side plugged honeycomb structure 40. 20 "residual cells 2b open at both ends" are arranged, and the honeycomb catalyst body 20 is extended over the extension of "residual cells 32b open at both ends" of the second one-side plugged honeycomb structure 40. The end face of the second one-side plugged honeycomb structure 40 is arranged on the other end face 5 of the honeycomb catalyst body 20 so that the “predetermined cells 2a in which the first plugged portions 11 are formed” are arranged. The honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are accommodated in the can body 50 with the (other end face 35) in contact with each other. By this step, the exhaust gas purification apparatus 100 can be obtained. The exhaust gas purification apparatus 100 has a structure in which the other end face 5 side of the remaining cells 2b of the honeycomb catalyst body 20 is closed by the second one-side plugged honeycomb structure 40. As described above, since the second one-side plugged honeycomb structure 40 is manufactured separately from the honeycomb catalyst body 20, the plugged portion of the second one-side plugged honeycomb structure 40 has a high temperature (the catalyst is deteriorated). It can be formed by firing at a firing temperature higher than the temperature at which it is performed. Thereby, it is possible to manufacture the exhaust gas purification apparatus 100 in which the plugged portions having excellent heat resistance are formed in both the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40.

  The method for manufacturing the second one-side plugged honeycomb structure 40 used in the canning step is not particularly limited, but for example, it is preferably manufactured as follows. That is, as shown in FIG. 8, a second honeycomb molded body 31 having partition walls 33 that define a plurality of cells 32 that penetrate from one end face 34 to the other end face 35 and serve as fluid flow paths is formed by extrusion molding. The second honeycomb formed and filled with the second plugging material in the opening portion of the predetermined cell 32a on the one end face 34 of the second honeycomb molded body 31, and filled with the second plugging material. The molded body 31 is preferably fired to form the second one-side plugged honeycomb structure 40 having the second plugged portions 41 on one end face 34. After the second honeycomb formed body 31 is fired, the second plugging member may be filled and further fired.

  The method for extruding the second honeycomb formed body 31 is not particularly limited, but for example, the methods mentioned as preferred methods for extruding the first honeycomb formed body 1 are preferable.

  The forming raw material is preferably a ceramic raw material added with a dispersion medium and an additive, and examples of the additive include an organic binder, a pore former, and a surfactant. Examples of the dispersion medium include water.

  Ceramic raw materials include silicon carbide, silicon-silicon carbide composite material, cordierite forming raw material, mullite, alumina, spinel, silicon carbide-cordierite composite material, lithium aluminum silicate, aluminum titanate, iron-chromium-aluminum alloy It is preferably at least one selected from the group consisting of Among these, silicon carbide or aluminum titanate is preferable. The ceramic raw material that forms the first honeycomb formed body and the ceramic raw material that forms the second honeycomb formed body are different. It is preferable that the ceramic raw material forming the first honeycomb formed body is a cordierite forming raw material, and the ceramic raw material forming the second honeycomb formed body is silicon carbide or aluminum titanate. This has the advantage that the regeneration limit is improved.

  The types and contents of the organic binder, the pore former, the surfactant and the dispersion medium are preferably those listed as preferable in the method for manufacturing the first honeycomb molded body 1.

  By adjusting the particle size and blending amount of the ceramic raw material (aggregate particles) used and the particle size and blending amount of the pore former to be added, a porous substrate having a desired porosity and average pore size is obtained. Can do.

  Next, the second honeycomb formed body 31 may be dried. The drying method is not particularly limited, and the methods listed as preferable methods in the method for manufacturing the first honeycomb formed body 1 are preferable.

  Next, the first plugging material is filled in the opening portion of the predetermined cell 32 a on one end face 34 of the second honeycomb formed body 31. The method for filling the first plugging material is not particularly limited, and the methods listed as preferable methods in the method for manufacturing the first honeycomb formed body 1 are preferable. The ceramic raw material is preferably the same as the ceramic raw material used for forming the second honeycomb formed body 31.

  Next, it is preferable to dry the second honeycomb formed body 31 filled with the second plugging material in the “openings of predetermined cells” on the one end face 34. The drying method is not particularly limited, and the methods mentioned as the preferable methods in the method for manufacturing the first honeycomb formed body 1 are preferable.

  Next, the second honeycomb formed body 31 filled with the second plugging material in the openings of the predetermined cells 32a on the one end face 34 is calcined before firing, and then fired, It is preferable to obtain the second one-side plugged honeycomb structure 40. Although the method of calcination and firing is not particularly limited, the method mentioned as a preferable method in the method for manufacturing the first honeycomb formed body 1 is preferable. When the material of the second plugging portion is silicon carbide, the firing temperature is preferably 1200 to 1600 ° C, and more preferably 1300 to 1500 ° C. The firing time is preferably about 1 to 20 hours. When the material of the second plugging portion is aluminum titanate, the firing temperature is preferably 1350 to 1500 ° C, and more preferably 1400 to 1450 ° C. The firing time is preferably about 1 to 10 hours.

  In the method for manufacturing the exhaust gas purification apparatus of the present embodiment, it is preferable that the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 have the same cross-sectional size and shape perpendicular to the central axis. Furthermore, it is preferable that the cross-sectional shape orthogonal to the central axis of each cell, the thickness of each partition wall, and each cell density are the same.

  In the canning step, “both ends of the honeycomb catalyst body 20 are open on the extension of the“ predetermined cell 32a in which the second plugging portion 41 is formed ”of the second one-side plugged honeycomb structure 40. "The remaining cells 2b" to be disposed, and the "first plugging of the honeycomb catalyst body 20 on the extension of the" residual cells 32b open at both ends "of the second one-side plugged honeycomb structure 40 The end face (the other end face 35) of the second one-side plugged honeycomb structure 40 is formed on the other end face 5 of the honeycomb catalyst body 20 so that the predetermined cell 2a in which the portion 11 is formed is disposed. By abutting, a series-type honeycomb filter 101 in which the honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 are connected in series as shown in FIGS. 2A and 2B is formed. Therefore, in the canning step, the in-line honeycomb filter 101 is accommodated in the can body 50, and the exhaust gas purification device 100 is formed. The honeycomb catalyst body 20 and the second one-side plugged honeycomb structure 40 may be bonded by an adhesive or the like, or may be accommodated in the can without being bonded by the adhesive or the like.

  Further, when the series-type honeycomb filter 101 is stored in the can body 50, as shown in FIG. 1, the series-type honeycomb filter 101 is stored in a compressed state in the can body 50 with the outer periphery covered with the cushion material 51. It is preferable to do. Examples of the cushion material 51 include a ceramic fiber mat. Thereby, the serial type honeycomb filter 101 can be stabilized in the can 50.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

( Reference Example 1)
The cordierite-forming raw material from which the cordierite is obtained by firing is mixed with water and binder, mixed, kneaded, and extruded to partition a plurality of cells that penetrate from one end face to the other end face and serve as fluid flow paths. A first honeycomb formed body having partition walls mainly composed of ceramic to be formed was obtained.

  Next, a first plugging material was filled in an opening of a predetermined cell on one end face of the obtained first honeycomb formed body. When filling the plugging material, the cells in which the first plugged portions are formed and the cells in which the first plugged portions are not formed are arranged in a checkered pattern on one end face. When filling the first plugging material, a mask was applied to one end face, a hole was formed in a predetermined cell using a laser, and the first plugging material was filled from the hole. The filling method is such that the first plugging material is stored in the container, and the end surface on the side where the plugging of the first honeycomb molded body is formed is placed in the container so that the end surface of the honeycomb molded body is immersed. It was set as the method of immersing in.

  The composition of the first plugging material was the cordierite forming raw material used for forming the first honeycomb formed body.

  The first honeycomb formed body filled with the first plugging material is dried and fired to obtain a first one-side plugged honeycomb structure having a first plugged portion on one end face. It was.

  Next, from one end face side where the first plugged honeycomb structure of the first one-side plugged honeycomb structure is formed, the catalyst slurry is caused to flow into a cell having both end faces opened, A catalyst was applied to the entire partition wall surface in the open cell to form a honeycomb catalyst body (honeycomb (A)). Further, after the catalyst slurry was allowed to flow into the cell, the excess slurry was blown off with compressed air. Then, by drying and baking the catalyst, a honeycomb catalyst body in which the catalyst was coated (supported) on the entire partition wall surface in the cell was obtained. The catalyst was baked at 550 ° C. As the catalyst slurry, a mixture of platinum (Pt), activated alumina, ceria as an oxygen storage agent and purified water with stirring was used. The amount of noble metal (Pt) per liter of honeycomb structure was 2 g. Further, the coating amount of the catalyst slurry was 100 g per liter of the honeycomb structure.

The honeycomb catalyst body obtained had a partition wall porosity of 50% and an average pore diameter of 18 μm. The porosity and average pore diameter are values measured with a mercury porosimeter. The obtained honeycomb catalyst body has a partition wall thickness of 300 μm, a cell density of about 46 cells / cm ² , a cell cross-sectional shape of a regular square, a bottom surface diameter of 152 mm, and a length of 145 mm. It was cylindrical.

  Next, by adding water and a binder to silicon carbide (SiC) powder, mixing, kneading, and extrusion molding, a plurality of cells penetrating from one end face to the other end face and serving as a fluid flow path are partitioned and formed. A second honeycomb formed body having partition walls mainly composed of ceramic was obtained.

  Next, the second plugging material is filled in the opening portion of a predetermined cell on one end face of the obtained second honeycomb molded body, and the second honeycomb material is filled with the second plugging material. The molded body is fired at 1450 ° C. for 2 hours to sinter the second plugging material and the second honeycomb molded body, and the second one side having the second plugging portion on one end face A plugged honeycomb structure (honeycomb (B)) was formed. On one end face, the cells in which the second plugged portions are formed and the cells in which the second plugged portions are not formed are arranged in a checkered pattern. When filling the second plugging material, a mask was applied to one end face, a hole was formed in a predetermined cell using a laser, and the second plugging material was filled from the hole. In the filling method, the second slurry is stored in the container, and the end face on the side where the plugging of the second honeycomb formed body is formed is immersed in the container so that the end face of the honeycomb formed body is immersed. It was a method.

  As the second plugging material, the SiC powder used for forming the second honeycomb formed body was used.

  The second honeycomb formed body filled with the second plugging material is dried and degreased in the air atmosphere, and then fired in an Ar inert atmosphere, and the second plugging portion is formed on one end face. A second one-side plugged honeycomb structure having the above was obtained.

The porosity of the partition walls of the obtained second one-side plugged honeycomb structure was 50%, and the average pore diameter was 18 μm. The porosity and average pore diameter are values measured with a mercury porosimeter. The obtained second one-side plugged honeycomb structure has a partition wall thickness of 300 μm, a cell density of about 46 cells / cm ² , a cell cross-sectional shape of a regular tetragon, and a bottom diameter of 152 mm, The length was 5 mm.

  As a can body for housing the honeycomb catalyst body and the second one-side plugged honeycomb structure, a tube made of stainless steel was used. One end of the can was squeezed so that the diameter of the cross section perpendicular to the central axis was 80 mm.

  As a cushioning material wound around the outer periphery of the honeycomb catalyst body and the second one-side plugged honeycomb structure when the honeycomb catalyst body and the second one-side plugged honeycomb structure are housed (canned) in the can body, A thermally expandable ceramic fiber mat was used.

  In the second one-side plugged honeycomb structure, a remaining cell having both ends of the honeycomb catalyst body opened is disposed on an extension of a predetermined cell in which the second plugged portion is formed, and the second The honeycomb catalyst body is arranged such that a predetermined cell in which the first plugged portion of the honeycomb catalyst body is formed is disposed on the extension of the remaining cells where both ends of the one-side plugged honeycomb structure are open. In the state where the end face of the second one-side plugged honeycomb structure is brought into contact with the other end face of this, and the cushion material is wound around the outer periphery, the honeycomb catalyst body and the second one-side plugged honeycomb are pushed into the can body. The structural body is accommodated in a can body, and a pipe that is narrowed so that the diameter of the cross section perpendicular to the central axis is 80 mm is welded to the other end of the can body (the welded portion is not shown). An exhaust gas purification apparatus having the structure shown in FIG. 1 was obtained.

  The “regeneration limit” and “heating vibration test” were performed using the obtained exhaust gas purification device. The results are shown in Table 1. In Tables 1 and 2, the “regeneration limit” column describes the ratio to the “regeneration limit” value in Comparative Example 1 when “honeycomb (B) plugging position” is “outside”. When “B) plugging position” is “inside”, the ratio to the value of “regeneration limit” in Comparative Example 3 is described. In the “heating vibration test”, when the movement amount (deviation amount) of the “contact surface between the honeycomb catalyst body and the second one-side plugged honeycomb structure” after 100 hours is less than 0.2 mm In the case of “◎”, 0.2 to 0.4 mm, “◯”, and 0.4 to 0.6 mm (not including 0.4 mm), “Δ”. If the moving amount of the contact surface after 100 hours is 0.6 mm or less, there is no practical problem.

  In Tables 1 and 2, in the columns of “Material of Honeycomb (A)” and “Material of Honeycomb (B)”, “CD” indicates “Cordierite”, “AT” indicates aluminum titanate, “ “SiC” indicates silicon carbide. In addition, the columns of “the length of the honeycomb (A)” and “the length of the honeycomb (B)” indicate the lengths in the central axis direction of the side portions of the honeycomb (A) and the honeycomb (B), respectively. Further, “square” in the column of “cell shape of honeycomb (A) (B)” indicates that the cell shape in a cross section perpendicular to the central axis of honeycombs (A) and (B) is a quadrangle. In the “cell shape of honeycomb (A) (B)” column, “square + octagon” is an octagonal cell having a cross section perpendicular to the central axis of honeycombs (A) and (B). It shows that the rectangular cells having a small area are alternately arranged. In this case, the honeycomb catalyst body and the second one-side plugged honeycomb structure are arranged so that the quadrangular cells face each other and the octagonal cells face each other, It is in contact. In the case of the “square + octagon”, the area of the octagonal cell is 1.8 times the area of the square cell. Further, in the column of “connected part structure”, “planar” means an end face that comes into contact (joins) with the second one-side plugged honeycomb structure (honeycomb (B)) of the honeycomb catalyst body (honeycomb (A)). (In this case, the shape of the end surface in contact with the honeycomb catalyst body of the second one-side plugged honeycomb structure is also planar).

  In the column of “connected portion structure”, “concave / convex: 1 mm” is a curved surface having a convex end surface in contact with the second one-side plugged honeycomb structure of the honeycomb catalyst body, and the height of the convex curved surface is high. The length H (see FIG. 5) is 1 mm. Moreover, the thing with a different numerical value part (1 mm) of said "unevenness | corrugation: 1 mm" shows that the height H of a convex-shaped curved surface differs. In addition, in the column of “connected portion structure”, “projection 1.0 mm × 2” means that two of the second plugged portions of the second one-side plugged honeycomb structure (honeycomb (B)) are projected. It is a plugging portion, and the length of the protruding portion of the protruding plugged portion (the length in the central axis direction of the honeycomb (B)) is 1.0 mm. In addition, “protrusion 0.5 mm × 3” is a protruding plugged portion in which three of the second plugged portions of the second one-side plugged honeycomb structure (honeycomb (B)) are protruding plugged portions. It indicates that the length of the protruding portion of the plugged portion (the length in the central axis direction of the honeycomb (B)) is 0.5 mm. In the “honeycomb (B) plugging position” column, “outside” indicates that the second plugged portion of the second one-side plugged honeycomb structure (honeycomb (B)) is shown in FIG. As in the case of the exhaust gas purification apparatus shown, it is shown that it is disposed on the end face (outer end face) on the side that does not contact the honeycomb catalyst body. Further, in the column “Honeycomb (B) plugging position”, “inside” indicates that the second plugged portion of the second one-side plugged honeycomb structure (honeycomb (B)) is shown in FIG. As shown in the contact state of the illustrated honeycomb catalyst body and the second one-side plugged honeycomb structure, this indicates that the honeycomb catalyst body is disposed on the end face (inner end face) on the side in contact with the honeycomb catalyst body. Further, “None” in the “Honeycomb (B) catalyst supported” column indicates that no catalyst is supported on the honeycomb (B). “Present” in the “Honeycomb (B) catalyst support” column indicates that the catalyst is supported on the honeycomb (B).

(Reproduction limit)
Increase the amount of soot accumulated in the exhaust gas purification device, regenerate (burn soot), and confirm the limit of cracking. Soot is deposited by causing combustion gas containing soot generated by combustion of diesel fuel (light oil) to flow into the exhaust gas purification device. And once cooled to room temperature, by flowing a combustion gas containing oxygen at a constant rate at 680 ° C. into the exhaust gas purification device, and reducing the flow rate of the combustion gas when the pressure loss of the exhaust gas purification device is reduced, The soot is rapidly burned, and then the presence or absence of cracks in the honeycomb catalyst body and the one-side plugged honeycomb structure is confirmed. This test starts from 4 g per liter of the total volume of the honeycomb catalyst body and the one-side plugged honeycomb structure (hereinafter referred to as 4 g / liter, etc.) until the occurrence of cracks is observed. Repeatedly increasing by 5 (g / liter). The measurement was performed for five (N = 5), and the average value was taken.

(Heating vibration test)
While the inlet gas temperature is 900 ° C., the vibration acceleration is 50 G, the vibration frequency is 200 Hz, and the exhaust gas heated is flowed into the exhaust gas purifier, the honeycomb catalyst body and the second one-side plugged honeycomb structure are axially Vibration was given by exhaust gas. The evaluation is “◎”, 0 when the movement amount (deviation amount) of “the contact surface between the honeycomb catalyst body and the second one-side plugged honeycomb structure” after 100 hours is less than 0.2 mm. In the case of 2 to 0.4 mm, “◯” is indicated, and in the case of 0.4 to 0.6 mm (not including 0.4 mm), “Δ” is indicated. If the moving amount of the contact surface after 100 hours is 0.6 mm or less, there is no practical problem.

(Examples 9 to 11, 18, 19, 23, Reference Examples 1 to 8, 12 to 17, 20 to 22, 24, 25, Comparative Examples 1 to 4)
Honeycomb (A) material, honeycomb (B) material, honeycomb (A) length (mm), honeycomb (B) length, honeycomb (A) (B) cell shape, connection structure, honeycomb ( B) Exhaust gas purification devices were produced in the same manner as in Reference Example 1 except that the plugging position and the honeycomb (B) catalyst support were changed as shown in Tables 1 and 2 (Examples 9 to 11, 18, 19, 23, Reference Examples 1-8, 12-17, 20-22, 24, 25, Comparative Examples 1-4). In the same manner as in Reference Example 1, the “regeneration limit” test and the “heating vibration test” were performed using the obtained exhaust gas purification apparatus. The results are shown in Tables 1 and 2.

From Tables 1 and 2, by using cordierite as the honeycomb (A) and aluminum titanate or silicon carbide as the honeycomb (B), an exhaust gas purifying apparatus having an excellent regeneration limit can be obtained. As the material of the honeycomb (B), silicon carbide has a greater effect of improving the regeneration limit than aluminum titanate. Further, by making the structure of the connecting portion (the structure of the portion where the honeycomb catalyst body and the second one-side plugged honeycomb structure abut) be uneven, the durability of the exhaust gas purification device (result of the heating vibration test) is improved. It turns out that it improves (Examples 9-11, Example 18, Example 19, Example 23). Moreover, it turns out that durability (heating vibration test result) of an exhaust gas purification apparatus improves by protrusion plugging ( Reference Examples 12-14, Reference Example 20, Reference Example 21, Reference Example 24, Reference Example 25).

When the length of the honeycomb (B) was less than 10 mm, the heating vibration test was “Δ”. In addition, cells with a large cross-sectional area and cells with a small cross-sectional area are alternately arranged, and when particulate matter is deposited in a cell with a large cross-sectional area (in the case of cell shape “square + octagon”), the regeneration limit increases. Is found to be large. In addition, it can be seen that if two protruding plugged portions are provided, the result of the heating vibration test is good ( Reference Example 12, Reference Example 20, Reference Example 21).

  The exhaust gas purifying apparatus of the present invention collects and removes particulate matter in exhaust gas discharged from internal combustion engines such as automobile engines, construction machine engines, industrial machinery stationary engines, and other combustion equipment. It can be suitably used.

1: first honeycomb formed body, 2: cell, 2a: predetermined cell, 2b: remaining cell, 3: partition, 4: one end face, 5: other end face, 10: first one side plugging Honeycomb structure, 11: first plugging portion, 12: honeycomb substrate, 20: honeycomb catalyst body, 21: catalyst, 31: second honeycomb formed body, 32: cell, 32a: predetermined cell, 32b : Remaining cells, 33: partition walls, 34: one end surface, 35: other end surface, 40: second one-side plugged honeycomb structure, 41: second plugged portion, 41a: protruding plugged Part, 41b: projecting part, 42: honeycomb substrate, 50: can body, 51: cushion material, 52: can body inlet, 53: can body outlet, 100: exhaust gas purification device, 101: in-line honeycomb filter, G: Exhaust gas.

Claims (6)

A honeycomb base material having a porous partition wall mainly composed of ceramic and forming a plurality of cells that penetrate from one end face to the other end face and serve as a fluid flow path, on the one end face of the honeycomb base material A honeycomb catalyst body having a first plugged portion disposed in an opening of a predetermined cell, and a catalyst supported on a partition wall surface in the remaining cell having both ends opened;
A honeycomb base material having a porous partition wall mainly composed of ceramic and forming a plurality of cells that penetrate from one end face to the other end face and serve as a fluid flow path, and the one end face of the honeycomb base material A second one-side plugged honeycomb structure having a second plugged portion disposed in an opening of a predetermined cell in
A can body that houses the honeycomb catalyst body and the second one-side plugged honeycomb structure;
The material of the honeycomb base material of the honeycomb catalyst body is different from the material of the honeycomb base material of the second one-side plugged honeycomb structure,
In the second one-side plugged honeycomb structure, a remaining cell having both ends of the honeycomb catalyst body opened is disposed on an extension of the predetermined cell in which the second plugged portion is formed. In addition, the predetermined cell in which the first plugging portion of the Nicham catalyst body is formed on the extension of the remaining cell that opens at both ends of the second one-side plugged honeycomb structure is disposed. In this way, the honeycomb catalyst body and the second one-side plugged honeycomb in a state where the end face of the second one-side plugged honeycomb structure is in contact with the other end face of the honeycomb catalyst body. And the structure is stored in the can body ,
The length of the second one-side plugged honeycomb structure in the central axis direction is 10 mm or more, and the end face of the second one-side plugged honeycomb structure is brought into contact with the other end face of the honeycomb catalyst body. 40% or less of the total length in the central axis direction when
The honeycomb catalyst body is a curved surface having a convex or concave shape on the other end surface,
In the second one-side plugged honeycomb structure, the end surface on the side in contact with the other end surface of the honeycomb catalyst body is complementary to the convex or concave curved surface of the other end surface of the honeycomb catalyst body. Exhaust gas purification device having a concave or convex curved surface . 2. The exhaust gas purification apparatus according to claim 1, wherein the second one-side plugged honeycomb structure further includes a catalyst supported on a partition wall surface in the remaining cell having both ends opened. In the honeycomb catalyst body, in a cross section perpendicular to the central axis, an area of the predetermined cell in which the first plugging portion is disposed is smaller than an area of the remaining cell having both ends opened. Yes,
In the cross-section perpendicular to the central axis of the second one-side plugged honeycomb structure, the area of the predetermined cell in which the first plugged portion is disposed is equal to the remaining opening at both ends. The exhaust gas purification device according to claim 1 or 2, wherein the exhaust gas purification device is larger than an area of the cell. The exhaust gas purification apparatus according to claim 3 , wherein a height of the curved end surface formed in a convex shape of the honeycomb catalyst body or the second one-side plugged honeycomb structure in a central axis direction is 1 to 10 mm. . Among the second plugged portions disposed in the second one-side plugged honeycomb structure, two or more second plugged portions protrude outward from the one end surface. Projecting plugging part,
The protruding portion of the protruding plugged portion of the second one-side plugged honeycomb structure is inserted into the remaining cells where both ends of the honeycomb catalyst body are open, and the honeycomb catalyst body The exhaust gas purification apparatus according to any one of claims 1 to 4 , wherein an end face of the second one-side plugged honeycomb structure is brought into contact with the other end face. Any the material of the honeycomb substrate of the honeycomb catalyst body is cordierite, the material of the honeycomb substrate of the second one side-plugged honeycomb structure according to claim 1 to 5 is silicon carbide or aluminum titanate The exhaust gas purification device according to claim 1.

Images