JP2021038122A - Method for producing honeycomb structure body - Google Patents

Abstract

To provide a honeycomb structure body having high mechanical strength.SOLUTION: There is provided a method for producing a honeycomb structure body comprising a honeycomb fired body in which a plurality cells serving as flow passages of exhaust gas are arranged in parallel to each other across cell walls in the longitudinal direction, which comprises: a raw material composition preparation step of preparing a raw material composition comprising ceria-zirconia composite oxide particles, alumina particles, an inorganic binder and a glass material; a molding step of molding the raw material composition to prepare a honeycomb molded body in which a plurality cells are arranged in parallel to each other across cell walls in the longitudinal direction; and a firing process of firing the honeycomb molded body to obtain a honeycomb fired body, wherein the weight ratio of the glass material to the raw material composition is 0.5 to 5 wt.%.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a honeycomb structure.

Exhaust gas emitted from an internal combustion engine of an automobile or the like contains harmful gases such as carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbons (HC), and particulate matter (PM). An exhaust gas purification catalyst that decomposes such harmful gases is also called a three-way catalyst, and a catalyst layer is provided by wash-coating a slurry containing noble metal particles having catalytic activity on a honeycomb-shaped monolithic substrate made of cordierite or the like. Those are common and are used with a honeycomb filter for removing PM.

On the other hand, Patent Document 1 contains at least one co-catalyst selected from the group consisting of ceria, zirconia, and ceria-zirconia solid solution as a component of the cell wall as a filter for simultaneously removing the harmful gas and PM. However, an exhaust gas filter in which pores communicating with adjacent cell holes are formed on the cell wall is disclosed.

JP-A-2017-115786

However, the honeycomb filter containing a solid solution of ceria-zirconia as a main component as described in Patent Document 1 has low mechanical strength and may be damaged during production and use.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a honeycomb structure having high mechanical strength.

The method for producing a honeycomb structure of the present invention is a method for producing a honeycomb structure composed of a fired honeycomb structure in which a plurality of cells serving as flow paths for exhaust gas are arranged side by side in the longitudinal direction with a cell partition wall in between. By forming a raw material composition step for preparing a raw material composition containing zirconia composite oxide particles, alumina particles, an inorganic binder and a glass material, and molding the raw material composition, a plurality of cells are separated by a cell partition in the longitudinal direction. The weight ratio of the glass material to the raw material composition is 0, which includes a molding step of producing a honeycomb molded body arranged side by side in the above and a firing step of firing the honeycomb molded body to obtain a honeycomb fired body. It is characterized by having a weight of 5 to 5% by weight.

In the method for producing a honeycomb structure of the present invention, the raw material composition contains 0.5 to 5% by weight of a glass raw material.
Since the glass raw material is in a molten state under the firing conditions of the honeycomb fired body, if the raw material composition contains 0.5 to 5% by weight of the glass material, the ceria-zirconia composite oxide particles (hereinafter referred to as “Ceria-zirconia composite oxide particles”) are contained during firing. The glass raw material tends to collect at the junction (also referred to as the neck portion) of the CZ particles) and the alumina particles (hereinafter collectively referred to as the raw material particles). When the glass raw material gathers at the neck of the raw material particles, the raw material particles are fixed by the molten glass raw material, so that the adhesion between the raw material particles is improved and the mechanical strength of the honeycomb structure is improved. The glass particles made it easier for the inorganic binders in the raw material composition to collect at the neck of the raw material particles, and the inorganic binders improved the adhesion of the raw material particles, and the inorganic binders closed the pores in the cell partition. Is a continuous ventilation hole, so that when used as a filter, the gas permeability of the cell partition of the exhaust gas can be improved.
When the ratio of the glass raw material is less than 0.5% by weight, the effect of improving the adhesion between the raw material particles is not sufficient. Further, when the ratio of the glass raw material exceeds 5% by weight, the ratio of the glass raw material to the entire honeycomb structure is too large to exhibit sufficient catalytic activity.

In the method for producing a honeycomb structure of the present invention, the glass raw material is preferably glass fiber having an average fiber length of 15 to 100 μm.

When the glass raw material is a glass fiber having an average fiber length of 15 to 100 μm, the molten glass raw material is easily dispersed among the raw material particles, so that the mechanical strength of the honeycomb structure is further improved.

In the method for manufacturing a honeycomb structure of the present invention, in the molding step, one end of the cell is sealed, the end on the exhaust gas inlet side is opened, and the end on the exhaust gas outlet side is the eye. It is preferable to further include a step of producing a sealed exhaust gas introduction cell and an exhaust gas discharge cell in which the end on the exhaust gas outlet side is opened and the end on the exhaust gas inlet side is sealed.

In the method for producing a honeycomb structure of the present invention, the molten glass raw material is collected at the neck portion of the raw material particles to form a structure in which the raw material particles are continuously connected by the neck portion, and the gap of the structure is a filter. It is thought that it will be a continuous ventilation hole suitable for the application. Therefore, if the molding step further includes the above steps, a honeycomb structure having high filter performance can be obtained.

FIG. 1A is a perspective view schematically showing an example of a honeycomb structure, and FIG. 1B is a sectional view taken along line AA in FIG. 1A. FIG. 2A is a perspective view schematically showing another example of the honeycomb structure, and FIG. 2B is a sectional view taken along line BB in FIG. 2A.

(Detailed description of the invention)
[Honeycomb structure]
First, the honeycomb structure to be manufactured by the method for manufacturing the honeycomb structure of the present invention will be described.

The honeycomb structure is composed of a honeycomb fired body in which a plurality of cells serving as an exhaust gas flow path are arranged side by side in the longitudinal direction with a cell partition wall interposed therebetween.
In the honeycomb fired body, a plurality of cells are arranged side by side in the longitudinal direction of the honeycomb fired body with the cell partition wall interposed therebetween.

The honeycomb fired body contains CZ particles, alumina particles, an inorganic binder and a glass material.
As will be described later, the fired honeycomb body is produced by molding a raw material composition containing CZ particles, alumina particles, an inorganic binder and a glass material, and then firing the mixture.

The honeycomb structure may include a single honeycomb fired body, a plurality of honeycomb fired bodies, or a plurality of honeycomb fired bodies may be bonded by an adhesive.

In the honeycomb structure, an outer peripheral coat layer may be formed on the outer peripheral surface of the honeycomb fired body.

FIG. 1A is a perspective view schematically showing an example of a honeycomb structure, and FIG. 1B is a sectional view taken along line AA in FIG. 1A.
The honeycomb structure 10 shown in FIG. 1A includes a single first honeycomb fired body 11 in which a plurality of cells 12 are arranged side by side in the longitudinal direction with the cell partition wall 13 interposed therebetween. The first honeycomb fired body 11 contains CZ particles, alumina particles, an inorganic binder, and a glass material, and has the shape of an extruded body.
The shape of the honeycomb structure 10 is columnar.

As shown in FIG. 1 (b), the exhaust gas G that has flowed into any cell 12 of the honeycomb structure 10 from one end (exhaust gas inflow side end) 14 (in FIG. 1 (b), the exhaust gas is G. (Indicated by, and the flow of the exhaust gas is indicated by an arrow), when passing through the cell 12, comes into contact with the catalyst supported on the cell partition wall of the honeycomb structure. As a result, harmful components such as NOx contained in the exhaust gas G are purified. Further, the purified exhaust gas G is discharged from the other end (exhaust gas outflow side end) 15 of the cell 12.
As described above, by using the honeycomb structure 10, harmful components such as NOx in the exhaust gas can be suitably purified.

In the honeycomb structure, the porosity of the cell partition wall of the honeycomb fired body is preferably 40 to 80% by volume.
When the porosity of the cell partition wall of the honeycomb fired body is 40 to 80% by volume, both high mechanical strength and exhaust gas purification performance can be achieved at the same time.

The porosity of the cell partition wall of the honeycomb fired body can be measured by the mercury press-fitting method.

If the porosity of the cell bulkhead of the honeycomb fired body is less than 40% by volume, the proportion of pores that can contribute to gas passage in the cell bulkhead is reduced, and the pressure loss may be improved. On the other hand, if the porosity of the cell partition wall of the honeycomb fired body exceeds 80% by volume, the porosity of the cell partition wall becomes too high, so that the mechanical properties of the honeycomb structure deteriorate and the honeycomb structure is used. Cracks and breaks are likely to occur.

In the honeycomb structure produced by the method for producing the honeycomb structure of the present invention, the D50 in the pore size distribution of the macropores constituting the honeycomb fired body is preferably 5 to 20 μm.
When D50 in the pore size distribution of macropores is 5 to 20 μm, it has many pores (pores) having a size suitable for collecting PM, so that the collection efficiency of PM is high and the pressure loss is low. can do.

D50 in the pore size distribution of the macropores constituting the honeycomb fired body is the pore size distribution curve measured by the mercury intrusion method [horizontal axis: pore diameter (μm), vertical axis: log differential pore volume (mL / g). ] Can be obtained from.
As a specific measurement procedure by the mercury press-fitting method, a honeycomb fired body is cut into cubes having a side of about 0.8 cm, ultrasonically washed with ion-exchanged water, sufficiently dried, and used as a measurement sample. The pore size is measured by the mercury press-fitting method (according to JISR1655: 2003). That is, for example, the pore size of the obtained sample is measured using a Micromeritix automatic porosimeter Autopore III9405 manufactured by Shimadzu Corporation. The measurement range is 0.006 to 500 μm. At 100 to 500 μm, the measurement is performed at every 0.1 psia pressure, and at 0.006 to 100 μm, the measurement is performed at every 0.25 psia pressure. The D50 of the macropore is calculated with the pore diameter as the macropore. At that time, the contact angle is 130 ° and the surface tension is 485 mN / m.

The alumina particles constituting the honeycomb fired body are preferably θ-phase alumina particles.
Since the alumina particles are θ-phase alumina particles, they have high heat resistance, so that they can support a noble metal and exhibit high exhaust gas purification performance even after long-term use.

In the honeycomb structure of the present invention, the content ratio of alumina particles is preferably 15 to 35% by weight.
Further, in the honeycomb structure of the present invention, the content ratio of CZ particles is preferably 35 to 65% by weight.

The honeycomb fired body contains a glass material.
The glass material is preferably contained in an amount of 1 to 10% by weight based on the total weight of the honeycomb fired body.

It is preferable that the honeycomb fired body further contains alumina fibers.
This is because the mechanical properties of the honeycomb fired body can be improved by including the alumina fiber.

The content ratio of the inorganic binder to the honeycomb fired body is preferably 0.1 to 10% by weight, and the content ratio of the alumina fiber is preferably 10 to 40% by weight.

The shape of the fired honeycomb body is not limited to a columnar shape, and examples thereof include a prismatic column, an elliptical columnar shape, an oblong columnar shape, and a round chamfered prismatic shape (for example, a round chamfered triangular columnar shape).

The shape of the cells of the honeycomb fired body is not limited to the square columnar shape, and examples thereof include a triangular columnar column and a hexagonal columnar column.

The density of cells having a cross section perpendicular to the longitudinal direction of the honeycomb fired body is preferably ^{31 to 155 cells / cm 2.}

The thickness of the cell partition wall of the honeycomb fired body is preferably 0.05 to 0.50 mm, more preferably 0.10 to 0.30 mm.

When the outer peripheral coat layer is formed on the outer peripheral surface of the honeycomb fired body, the thickness of the outer peripheral coat layer is preferably 0.1 to 2.0 mm.

It is preferable that a precious metal is supported on the honeycomb fired body.
In the honeycomb structure, if a noble metal that functions as a catalyst is supported on the honeycomb fired body, it can also be used as a honeycomb catalyst for exhaust gas purification.
Examples of the noble metal include platinum, palladium, rhodium and the like.

In the honeycomb structure, the amount of the noble metal supported is preferably 0.1 to 15 g / L, more preferably 0.5 to 10 g / L.
As used herein, the amount of noble metal supported refers to the weight of the noble metal per apparent volume of the honeycomb structure. The apparent volume of the honeycomb structure is a volume including the volume of the voids, and includes the volume of the outer peripheral coat layer and / or the adhesive layer.

The honeycomb fired body has a plurality of cells, an exhaust gas introduction cell in which the end on the exhaust gas inlet side is opened and the end on the exhaust gas outlet side is sealed, and an exhaust gas introduction cell in which the end on the exhaust gas outlet side is opened and the exhaust gas inlet side. It is preferable that the end portion of the exhaust gas discharge cell is sealed.

When a plurality of cells have the above configuration, the exhaust gas that has entered the honeycomb fired body from the end on the exhaust gas inlet side passes through the cell partition wall and is discharged from the end on the exhaust gas outlet side. It can be used as a filter for.

An example of the structure of the honeycomb structure that can be used as a filter for removing PM will be described with reference to FIGS. 2 (a) and 2 (b).
FIG. 2A is a perspective view schematically showing another example of the honeycomb structure, and FIG. 2B is a sectional view taken along line BB in FIG. 2A.
In the honeycomb structure 20 shown in FIG. 2A, a large number of exhaust gas introduction cells 22a and exhaust gas discharge cells 22b are formed in the longitudinal direction of the cylindrical honeycomb fired body 21 (indicated by double-headed arrows a in FIG. 2A). The exhaust gas introduction cell 22a and the exhaust gas discharge cell 22b are formed so as to be separated from the cell partition wall 23.
Seen from one end (exhaust gas introduction side end) 24, the end 24 of the exhaust gas discharge cell 22b is sealed by the sealing portion 26b, and the exhaust gas introduction cell 22a is open. On the other hand, at the other end (exhaust gas discharge side end) 25, the exhaust gas introduction cell 22a is sealed by the sealing portion 26a, and the exhaust gas discharge cell 22b is open.

Since the end 25 of the exhaust gas introduction cell 22a is sealed, the exhaust gas G introduced from the end 24 into the exhaust gas introduction cell 22a passes through the cell partition wall 23, which is a porous wall, and then passes through the exhaust gas discharge cell 22b. It passes through and is discharged from the end 25. During this time, the particulate matter (hereinafter referred to as PM) in the exhaust gas is collected by the cell partition wall 23, and the exhaust gas is purified.

[Manufacturing method of honeycomb structure]
Next, a method for manufacturing the honeycomb structure of the present invention will be described.
The method for producing a honeycomb structure of the present invention is a method for producing a honeycomb structure composed of a fired honeycomb structure in which a plurality of cells serving as flow paths for exhaust gas are arranged side by side in the longitudinal direction with a cell partition wall in between. By forming a raw material composition step for preparing a raw material composition containing zirconia composite oxide particles, alumina particles, an inorganic binder and a glass material, and molding the raw material composition, a plurality of cells are separated by a cell partition in the longitudinal direction. The weight ratio of the glass material to the raw material composition is 0, which includes a molding step of producing a honeycomb molded body arranged side by side in the above and a firing step of firing the honeycomb molded body to obtain a honeycomb fired body. It is characterized by being 5 to 5% by weight.

(Raw material composition preparation process)
In the raw material composition preparation step, CZ particles, alumina particles, an inorganic binder and a glass material are mixed to prepare a raw material composition.

The weight ratio of the glass material to the raw material composition is 0.5 to 5% by weight.
Examples of the glass material used when preparing the raw material composition include glass particles and glass fibers, and glass fibers are preferable.

The glass material is preferably composed of at least one glass selected from the group consisting of soda-lime glass, non-alkali glass and borosilicate glass.

The glass raw material is preferably glass fiber having an average fiber length of 15 to 500 μm.
When the glass raw material is a glass fiber having an average fiber length of 15 to 500 μm, the molten glass raw material is easily dispersed among the raw material particles, so that the mechanical strength of the honeycomb structure is further improved.

The average fiber diameter of the glass fiber is not particularly limited, but is preferably 0.1 to 10 μm.
When the average fiber diameter of the glass fibers is less than 0.1 μm, the glass fibers are likely to be scattered in the manufacturing process, and the handleability is deteriorated. On the other hand, when the average fiber diameter of the glass fibers exceeds 10 μm, the distribution of the glass raw materials in the cell partition wall becomes biased.

As the alumina particles, those having an average particle diameter of 1 to 30 μm are preferably used.
Further, it is preferable to use CZ particles having an average particle diameter of 1 to 10 μm.
The average particle size of the CZ particles and the alumina particles can be determined by a laser diffraction type particle size distribution measuring device (MASTERSIER2000 manufactured by MALVERN).
Specifically, in the cumulative volume distribution curve of particles obtained by the above measuring device, the average particle size is the particle size in which the cumulative volume corresponds to 50% by volume from the smallest particle size.

As the alumina particles used when preparing the raw material composition, θ-phase alumina particles are preferable.

The raw material composition preferably contains an inorganic binder and further contains inorganic fibers.

The inorganic binder is not particularly limited, and examples thereof include solids contained in alumina sol, silica sol, titania sol, sepiolite, attapulsite, boehmite, and the like, and two or more of these inorganic binders may be used in combination. Of these, boehmite is preferred.

Boehmite is an alumina monohydrate represented by the composition of AlOOH and disperses well in a medium such as water. Therefore, in the method for producing a honeycomb structure of the present invention, it is preferable to use boehmite as a binder.

The material constituting the inorganic fiber is not particularly limited, and examples thereof include alumina, silica, silicon carbide, silica alumina, potassium titanate, aluminum borate, and the like, and two or more of them may be used in combination. Of these, alumina fiber is preferable.

The aspect ratio of the inorganic fiber is preferably 5 to 300, more preferably 10 to 200, and even more preferably 10 to 100.

If necessary, a pore-forming material may be added to the raw material composition.

Examples of the pore-forming material include acrylic resin, starch, carbon and the like, and among these, it is preferable to use acrylic resin.

Other raw materials used in preparing the raw material composition include organic binders, dispersion media, molding aids and the like.

The organic binder is not particularly limited, and examples thereof include methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, polyethylene glycol, phenol resin, epoxy resin, and the like, and two or more kinds may be used in combination.

The dispersion medium is not particularly limited, and examples thereof include water, an organic solvent such as benzene, an alcohol such as methanol, and two or more thereof may be used in combination.

The molding aid is not particularly limited, and examples thereof include ethylene glycol, dextrin, fatty acid, fatty acid soap, and polyalcohol, and two or more of them may be used in combination.

When CZ particles, alumina particles, alumina fibers, boehmite and glass fibers are used as the above-mentioned raw materials, the blending ratio of these is CZ particles: 40 to 60% by weight with respect to the total solid content remaining after the firing step in the raw materials. , Alumina particles: 15-35% by weight, Alumina fiber: 10-40% by weight, Boehmite: 0.1-10% by weight, Glass fiber: 1-10% by weight are preferable.

When preparing the raw material composition, it is preferable to mix and knead, and the mixture may be mixed using a mixer, an attritor or the like, or may be kneaded using a kneader or the like.

(Molding process)
In the molding step, by molding the raw material composition, a honeycomb molded body in which a plurality of cells are arranged side by side in the longitudinal direction with the cell partition wall interposed therebetween is produced.
Specifically, a continuous body of a honeycomb molded body having cells having a predetermined shape is formed by passing through a mold having a predetermined shape, and the honeycomb molded body is formed by cutting into a predetermined length.

Subsequently, the molded product molded by the above molding step is dried.
At this time, the honeycomb molded body can be dried to produce a honeycomb dried body using a dryer such as a microwave dryer, a hot air dryer, a dielectric dryer, a vacuum dryer, a vacuum dryer, or a freeze dryer. preferable.

In the present specification, the honeycomb molded body and the honeycomb dried body before the firing step are collectively referred to as a honeycomb molded body.

(Baking process)
In the firing step, a honeycomb fired body is produced by firing the molded body dried in the drying step. Since this step is degreasing and firing of the honeycomb molded body, it can be referred to as a "degreasing / firing step", but for convenience, it is referred to as a "baking step".

The temperature of the firing step is preferably 800 to 1300 ° C, more preferably 900 to 1200 ° C. The firing step time is preferably 1 to 24 hours, more preferably 3 to 18 hours. The atmosphere of the firing step is not particularly limited, but the oxygen concentration is preferably 1 to 20%.

A honeycomb structure can be manufactured by the above steps.

(Other processes)
The manufacturing method further includes, if necessary, a sealing step of sealing any end of the cells constituting the honeycomb molded body and a supporting step of supporting the precious metal on the fired honeycomb body. May be good.

(Seal process)
In the sealing step, a predetermined amount of a sealing material paste is filled in any end of the cells constituting the dried honeycomb body to seal the cells. When sealing the cells, for example, a mask for cell sealing is applied to the end surface of the honeycomb molded body (that is, the cut surface after cutting both ends), and the sealing material is applied only to the cells that need to be sealed. Fill the paste and allow the encapsulant paste to dry. Through such a step, a dried honeycomb body in which one end of the cell is sealed can be produced.
As the encapsulant paste, the above raw material composition can be used.
The sealing step may be performed after the firing step, or may be re-baked after the sealing step.

(Supporting process)
In the supporting step, for example, the honeycomb fired body or the honeycomb structure is immersed in a solution containing precious metal particles or complexes, and then pulled up and heated.
When the honeycomb structure includes an outer peripheral coat layer, the noble metal may be supported on the honeycomb fired body before the outer peripheral coat layer is formed, or the noble metal may be supported on the honeycomb fired body or the honeycomb structure after the outer peripheral coat layer is formed. It may be carried.

The amount of the noble metal supported in the above-mentioned supporting step is preferably 0.1 to 15 g / L, and more preferably 0.5 to 10 g / L.

When the outer peripheral coat layer is formed on the outer peripheral surface of the honeycomb fired body, the outer peripheral coat layer may be formed by applying the outer peripheral coat layer paste to the outer peripheral surface excluding both end faces of the honeycomb fired body and then drying and solidifying. it can. Examples of the paste for the outer peripheral coat layer include those having the same composition as the raw material composition.

(Example)
Hereinafter, examples in which the present invention is disclosed more specifically will be shown. The present invention is not limited to the following examples.

[Preparation of evaluation sample]
(Example 1)
CZ particles (average particle size: 8 μm) are 16.9% by weight, alumina particles (average particle size: 20 μm) are 8.5% by weight, boehmite as an inorganic binder is 0.9% by weight, average fiber diameter is 3 μm, average. Alumina fiber with a fiber length of 100 μm is 10.6% by weight, methylcellulose as an organic binder is 3.9% by weight, acrylic resin is 28.1% by weight as a pore-forming material, and glass fiber as a glass material (average fiber length:: 80 μm, average fiber diameter: 6 μm) was mixed and kneaded with 0.7% by weight, 2.9% by weight of polyoxyethylene oleyl ether as a molding aid and 27.5% by weight of ion-exchanged water were mixed and kneaded. , The raw material composition was prepared.

The raw material composition was extruded using an extrusion molding machine to prepare a columnar honeycomb molded body. Then, the honeycomb molded product is dried at an output of 1.74 kW and a reduced pressure of 6.7 kPa for 12 minutes using a vacuum microwave dryer, and then a sealing material is applied to one end of the cells constituting the honeycomb molded product. A sealing material paste having the same composition as the raw material composition used to prepare the honeycomb molded product is filled in a predetermined cell of the honeycomb molded product so that the paste is filled, and further at 120 ° C. under atmospheric pressure. It was dried for 10 minutes. Then, by degreasing and firing at 1150 ° C. for 10 hours, a honeycomb fired body (honeycomb structure) was produced. The honeycomb fired body had a columnar shape having a diameter of 118 mm and a length of 122 mm, a cell density of 46.5 cells / cm ² (300 cpsi), and a cell partition wall thickness of 0.203 mm (8 mil).

(Examples 2 to 4)
The honeycomb structures according to Examples 2 to 4 were produced in the same procedure as in Example 1 except that the composition of the raw material composition and the average fiber length of the glass fibers were changed as shown in Table 1.

(Comparative Example 1)
A honeycomb structure was produced in the same procedure as in Example 1 except that the composition of the raw material composition was changed as shown in Table 1.

[Measurement of fracture strength]
As the mechanical strength of the honeycomb structure, the bending strength was measured by the following method.
First, as a sample for measuring the bending strength at three points, ten members having a cross section of 4 cells × 4 cells and a length of 40 mm were prepared. A load was applied in a direction perpendicular to the main surface of the three-point bending strength measurement sample (the wider surface of the outer peripheral surface of the sample), and the breaking load (the load at which the sample broke) was measured. The breaking load was measured for 10 samples for measuring the bending strength at three points, and the average value was taken as the bending strength. The three-point bending strength test was carried out using an Instron 5582 with reference to JIS R 1601 at a distance between spans of 30 mm and a speed of 1 mm / min.
Table 2 shows the breaking strengths of the honeycomb structures produced in Examples 1 to 4 and the honeycomb structures produced in Comparative Example 1.

[Measurement of D50 of cell bulkhead by mercury press-fitting method]
For the honeycomb structures according to Examples 1 to 4 and Comparative Example 1, the D50 of the cell partition wall was determined by the above-mentioned mercury press-fitting method. The results are shown in Table 2.

From the above results, it can be seen that the honeycomb structure manufactured by the method for manufacturing the honeycomb structure of the present invention has sufficient mechanical strength.
Further, the honeycomb structure manufactured by the method for manufacturing the honeycomb structure of the present invention can reduce the pressure loss and has a macropore D50 of 5 to 20 μm, which is suitable for collecting PM. It can be seen that excellent filter performance is exhibited when one of the ends is sealed and used as a filter for removing PM.

10, 20 Honeycomb structure 11, 21 Honeycomb fired body 12, 22 Cell 13, 23 Cell partition wall 14, 24 One end 15, 25 The other end 22a Exhaust gas introduction cell 22b Exhaust gas discharge cell 26a, 26b Sealing part

Claims (3)

It is a method for manufacturing a honeycomb structure composed of a honeycomb fired body in which a plurality of cells serving as an exhaust gas flow path are arranged side by side in the longitudinal direction with a cell partition wall separated.
A raw material composition preparation step for preparing a raw material composition containing ceria-zirconia composite oxide particles, alumina particles, an inorganic binder and a glass material, and
A molding step of forming a honeycomb molded body in which a plurality of cells are arranged side by side in the longitudinal direction with a cell partition wall separated by molding the raw material composition.
Including a firing step of firing the honeycomb molded body to obtain a honeycomb fired body.
A method for producing a honeycomb structure, wherein the weight ratio of the glass material to the raw material composition is 0.5 to 5% by weight. The method for producing a honeycomb structure according to claim 1, wherein the glass raw material is a glass fiber having an average fiber length of 15 to 100 μm. In the molding step, the exhaust gas introduction cell in which one end of the cell is sealed, the end on the exhaust gas inlet side is opened, and the end on the exhaust gas outlet side is sealed, and the exhaust gas outlet side. The method for manufacturing a honeycomb structure according to claim 1 or 2, further comprising a step of producing an exhaust gas discharge cell in which the end portion of the honeycomb structure is opened and the end portion on the exhaust gas inlet side is sealed.

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