JPH06238167A - Crystalline aluminosilicate and catalyst for purification of exhaust gas - Google Patents

Abstract

(57) [Summary] [Object] To provide a crystalline aluminosilicate having excellent heat resistance. [Structure] The crystalline aluminosilicate comprises a plurality of crystal planes CF each having a Miller index h, k, l of 2 or less in the first crystal plane group having a lattice spacing of 4.0 Å or more.
Of ₁ indicates the maximum X-ray reflection intensity and (200) X-ray reflection intensity I ₁ of the plane lattice spacing is more 3 Å, of the second crystal plane group is less than 4 Å, a maximum X-ray reflection intensity The crystal plane CF ₂ shown, and therefore the X-ray reflection intensity I _{2 of the} (202) plane
The ratio I ₁ / I _{2 is set} to 0.76 ≦ I ₁ / I ₂ ≦ 1.10. The (200) plane is a crystal plane due to the periodicity of the cavity structure peculiar to crystalline aluminosilicate having fine pores at the molecular level, and the (202) plane is mainly composed of a SiO ₄ tetrahedral structure. Is a crystal plane resulting from the basic skeleton structure of the crystalline aluminosilicate.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a crystalline aluminosilicate and an exhaust gas purifying catalyst using the crystalline aluminosilicate as a carrier.

[0002]

2. Description of the Related Art Conventionally, this seed crystal aluminosilicate,
For example, as a zeolite and a catalyst having the same as a carrier, the one disclosed in JP-A-2-126941 is known, and the surface of this zeolite is treated by hydrothermal treatment to remove Al.
It has been transformed.

[0003]

The carrier for the exhaust gas purifying catalyst in the engine is required to have a heat resistance of 900 to 1000 ° C., but the conventional zeolite has a heat resistant temperature of about 700 ° C. When used as the carrier, there was a problem that the high temperature durability was poor.

In view of the above, it is an object of the present invention to provide the above-mentioned crystalline aluminosilicate capable of significantly improving the heat resistant temperature by specifying the crystal structure.

Another object of the present invention is to provide the catalyst having excellent high temperature durability and high exhaust gas purification rate by using the crystalline aluminosilicate as a carrier.

[0006]

The crystalline aluminosilicate according to the present invention has a lattice spacing of 4.0 Å or more.
In the crystal plane group of, the X-ray reflection intensity I _{1 of the} crystal face having the maximum X-ray reflection intensity among the plurality of crystal faces CF _{1 having} the mirror indices h, k, and 1 of 2 or less and the lattice plane spacing are 3Å above, of the second crystal plane group is less than 4 Å, the ratio I ₁ / I ₂ of the X-ray reflection intensity I ₂ of the crystal plane CF ₂ showing a maximum X-ray reflection intensity is 0.76 ≦ I ₁ / It is characterized in that I ₂ ≦ 1.10.

In the exhaust gas purifying catalyst according to the present invention, in the first crystal plane group having a lattice spacing of 4.0 Å or more,
Among a plurality of crystal planes CF ₁ each having a Miller index h, k, l of 2 or less, X of the crystal plane showing the maximum X-ray reflection intensity
A line reflection intensity I _1, the lattice spacing is more 3 Å, of the second crystal plane group is less than 4 Å, the ratio I ₁ of the X-ray reflection intensity I ₂ of the crystal plane CF ₂ showing a maximum X-ray reflection intensity / I ₂ is 0.
It is composed of a crystalline aluminosilicate with 76 ≦ I ₁ / I ₂ ≦ 1.10 and a catalytic metal supported on the crystalline aluminosilicate, the catalytic metal being Ib of the periodic table.
It is characterized in that it is at least one metal selected from at least one group selected from the group consisting of iron, iron and platinum.

[0008]

When the crystal structure of the crystalline aluminosilicate is specified as described above, the heat resistance temperature is 900 to 10
It can be raised to 00 ° C. The reason why the heat resistance is improved is considered as follows. That is, the crystal plane CF ₁ is a crystal plane due to the periodicity of the cavity structure peculiar to crystalline aluminosilicate having fine pores at the molecular level, and the crystal plane CF ₂ is mainly a SiO ₄ tetrahedral structure. 3 is a crystal plane resulting from the basic skeleton structure of the crystalline aluminosilicate composed of the parts. These crystal planes CF ₁ ,
When the ratio I ₁ / I ₂ of the X-ray reflection intensity of CF ₂ is set as the crystalline aluminosilicate has a basic skeleton structure with a firm which has a good crystal plane CF ₁ crystalline, This is a factor for improving heat resistance.

In a high-temperature environment containing water, the structure of ordinary crystalline aluminosilicate is destroyed by high-activity hot water, but the crystalline aluminosilicate according to the present invention has good heat resistance. It is stable even under the harsh environment described above.

However, the ratio of the X-ray reflection intensities I ₁ / I ₂
When I ₁ / I ₂ <0.76, the crystallinity of the crystal plane CF ₁ deteriorates and the heat resistance of the crystalline aluminosilicate decreases, while when I ₁ / I ₂ > 1.10, the basic skeleton structure As a result, the heat resistance of the crystalline aluminosilicate is similarly reduced.

On the other hand, since the exhaust gas purifying catalyst uses the crystalline aluminosilicate as a carrier, it has excellent high temperature durability and a high exhaust gas purifying rate even when exposed to high temperatures for a long time. As the method of supporting the metal for the catalyst, a solution method such as impregnation with a solution or an ion exchange method is applied.

[0012]

【Example】

A. About Crystalline Aluminosilicate Crystalline aluminosilicate includes unmodified mordenite as unmodified zeolite, modified mordenite produced by subjecting unmodified ZSM-5 zeolite and the like to a predetermined modification treatment,
Modified zeolites such as modified ZSM-5 zeolite are suitable.

The reforming process is performed in the following procedure.
(A) The unmodified zeolite is put into a treatment tank containing water, 12N HCl is gradually added, and the temperature rising rate is 1.
After heating at 5 ° C./min for 1 hour, an HCl solution at 90 ° C. and a predetermined normality is formed. (B) The unmodified zeolite is kept at this temperature for a predetermined time, and at the same time, the HCl solution is stirred. In this case, a cooling tower is attached to the treatment tank and HCl is added.
The concentration of the solution is maintained at the specified level. (C) Cool the HCl solution having a predetermined normality to room temperature under the condition of the temperature decreasing rate of 3 ° C./min. (D) The modified zeolite is taken out of the treatment tank, washed with pure water until pH 5 or more, and then dried.

In the unmodified zeolite, the AlO ₄ tetrahedral structure is mainly distributed in the fine pore-forming portion of the skeleton structure. As a result, the modification treatment mainly causes the fine pore-forming portion of the unmodified zeolite. In, the following Al removal reaction occurs.

[0015] As shown in FIG. 1 (a), the fine hole forming section for forming micropores 1, a plurality of SiO ₄ coupled to each other by sharing the O atom tetrahedral structure 2 with one or more, In the illustrated example, for convenience, it is composed of three AlO ₄ tetrahedral structure parts 3.

When the unmodified zeolite having such a structure is subjected to the modification treatment with the HCl solution as described above, fine pores 1 are formed as shown in FIGS. 1 (b ₁ ) and (b ₂ ). Two or all of the Al atoms are detached and eluted from the fine pores 1, and the plurality of SiO ₄ tetrahedral structure portions 2 constituting the fine hole forming portion are separated from the adjacent SiO ₄ tetrahedral structure portions. SiO ₄ tetrahedral structures with one or two unshared O atoms (ions) are created.

As shown in FIGS. 1 (c ₁ ) and ₁ (c ₂ ), _one of the positive atoms such as H and Na and the positive group such as ammonium group which are chemically active to the non-covalent O atom, in the illustrated example, H atoms bond. In this case, Al remains in FIG. 1 (c ₁ ), and the AlO ₄ tetrahedral structure 3 containing Al has negatively charged O atoms, so that H atoms also bond to the O atoms. To do.

As described above, Al removal in the fine hole forming portion is performed.
When a reaction is generated and the abundance A of Al atoms in the fine pore forming part is set to 0% ≤ A ≤ 15.8%, crystals resulting from the periodicity of the cavity structure peculiar to zeolite having fine pores at the molecular level. Planes, and thus the first crystal plane group having a lattice spacing of 4.0 Å or more, Miller indices h, k,
Since the crystallinity of a plurality of crystal planes CF ₁ each having l of 2 or less is improved, the X-ray reflection intensity of the crystal planes CF ₁ is increased. Improving the crystallinity of the crystal surface CF ₁ is confirmed by measuring X-ray reflection intensity I ₁ of the crystal plane showing a maximum X-ray reflection intensity of these crystal planes CF _1.

On the other hand, since the above-mentioned modification treatment mainly aims at the de-Al reaction in the fine pore forming portion, it is possible to destroy the basic skeleton structure mainly composed of the SiO ₄ tetrahedral structure portion of zeolite. There is no such thing. The crystal plane resulting from this basic skeleton structure is the crystal plane CF ₂ showing the maximum X-ray reflection intensity in the second crystal plane group having a lattice plane interval of 3Å or more and less than 4Å. CF ₂
It can be said that the basic skeleton structure is maintained if the value of the X-ray reflection intensity I ₂ before and after the modification is substantially constant.

[0020] Therefore, when conducted various experiments, the ratio I ₁ / I ₂ of the X-ray reflection intensity of the crystal plane CF _1, CF ₂ 0.7
By setting 6 ≦ I ₁ / I ₂ ≦ 1.10, the modified zeolite has a crystallographic plane CF ₁ with good crystallinity and a solid basic skeleton structure. Can be raised to 1000 ° C,
It was proved that.

A specific example will be described below. Example-I In this example, commercially available pelletized Na-type unmodified mordenite (SiO ₂ / A) was used as the unmodified zeolite.
1 ₂ O ₃ molar ratio = 16.6) was used. Table 1 shows 90 ° C. in the modification treatment of Examples 1 to 3 and Comparative Example.
The normality of the HCl solution and the 90 ° C isothermal holding time are shown.

[0022]

[Table 1] Table 2 shows the total Al abundance in Examples 1 to 3, the comparative example, and the unmodified mordenite, and the Si content, the Al content, and the Al abundance A in the fine hole forming portion, respectively. The Al existence rate A is A (%) = {Al
Content / (Si content + Al content)} × 100. This is the same for each of the following examples.

[0023]

[Table 2] From Table 2, it can be seen that when the modifying treatment conditions are made severe, the Al abundance A sharply decreases because the Al removal reaction in the fine hole forming portion is actively performed. The fact that the Al abundance ratio A has a negative value means that not only all of the Al atoms in the fine hole forming portion have been released but also the Al removal reaction has occurred in the basic skeleton structure. If it occurs above, destruction of the basic skeleton structure will be caused.
The negative value of the Al existence rate A is the same for each of the subsequent examples.

FIG. 2 shows the X-ray diffraction result of Example 1.

Each peak of the first crystal plane group having a lattice plane spacing of 4.0 Å or more appears at an angle 2θ of 2θ ≦ 22 °. Therefore, the first crystal plane group has a Miller index (hereinafter the same). And (110) plane, (020) plane, (200) plane,
(111) plane, (130) plane, (310) plane, (33
0) plane / (400) plane are included. Here, a plurality of crystal planes CF ₁ whose Miller indices h, k, and l are 2 or less, respectively.
Has (110) plane, (020) plane, (200) plane, (1
11) Face is applicable. These crystal planes CF ₁ are crystal planes due to the periodicity of the cavity structure peculiar to mordenite, and the crystal plane showing the maximum X-ray reflection intensity is the (200) plane.

Each peak of the second crystal plane group having a lattice plane spacing of 3 Å or more and less than 4 Å has an angle 2θ of 22 ° <2θ ≦ 30.
Appear in °, and therefore the second group of crystal planes is (150)
Plane, (241) plane, (002) plane, (202) plane, (3
The (50) plane and the (132) plane / (511) plane / (530) plane are included. The (202) plane corresponds to the crystal plane CF ₂ showing the maximum X-ray reflection intensity in the second crystal plane group. This (202) plane is mainly Si in mordenite.
It is a crystal plane resulting from the basic skeleton structure composed of the O ₄ tetrahedral structure portion.

FIGS. 3 and 4 show the X-ray diffraction results of Examples 2 and 3, FIG. 5 of the comparative example, and FIG. 6 of the unmodified mordenite. 3 to 6, in Example 2, Example 3, Comparative Example and unmodified mordenite, the crystal plane showing the maximum X-ray reflection intensity among the crystal planes CF ₁ is the (200) plane, and It can be seen that the crystal plane CF ₂ is the (202) plane.

Table 3 shows the X-ray reflection intensity I ₁ of the (200) plane in Examples 1 to 3, Comparative Examples and unmodified mordenite, and the X-ray reflection intensity I of the (202) plane in Example 1 and the like. ₂ and the ratio of both X-ray reflection intensities I ₁ and I ₂ I ₁ /
I ₂ is shown.

[0029]

[Table 3] From Table 3, in Examples 1 to 3, (200)
X-ray reflection intensity I _{1 of the} surface is A compared to unmodified mordenite
l It increases with the decrease of the existence ratio A, while (20
It can be seen that the X-ray reflection intensity I ₂ of the 2) surface is substantially the same as that of the unmodified mordenite. In the case of the comparative example, (20
The X-ray reflection intensity I ₁ of the (0) plane is increased as compared with that of the unmodified mordenite, but the X-ray reflection intensity I ₂ of the (202) plane is significantly decreased as compared with that of the unmodified mordenite. .

Regarding Examples 1 to 3, Comparative Examples and unmodified mordenite, the heating temperature was 600 to 1 in the air.
A thermal deterioration test was performed under the conditions of 100 ° C. and a heating time of 18 hours, and then a powder X-ray diffraction by Cu-Kα ray was performed for Example 1 and the like to observe the crystal breakdown state by heat. Got the result.

In Table 4 and FIG. 7, the mark “◯” indicates that the X-ray reflection intensity did not change after the test, and the mark “Δ” indicates the decrease rate of the X-ray reflection intensity after the test. The case is less than 10%, and the mark "x" indicates the case where the reduction rate of the X-ray reflection intensity after the test is 10% or more. FIG. 7 shows the (200) plane.

[0032]

[Table 4] As is clear from Tables 2 to 4 and FIG.
In the case of Example 3, the Al existence rate A in the fine hole forming portion is A ≦ 15.8% and the ratio I ₁ / I ₂ is 0.76 ≦.
Due to the fact that I ₁ / I ₂ ≦ 1.10, the heat resistant temperature is improved to 900 to 1000 ° C. In the case of the comparative example, the ratio I ₁ / I ₂ is I ₁ / I ₂ > 1.10, and since the basic skeleton structure is destroyed by the modification treatment, the heat resistance temperature is lower than that of unmodified mordenite. It has been found. In the case of unmodified mordenite, the above ratio I ₁ / I
₂ is I ₁ / I ₂ <0.76 and the crystallinity of the crystal plane CF ₁ is poor, so that the heat resistance temperature is low. [Example-II] In this example, unmodified ZSM-5 zeolite manufactured by the following method was used as the unmodified zeolite.

First, colloidal silica and aluminum nitrate are mixed at a SiO ₂ / Al ₂ O ₃ molar ratio of 35.2, and tetrapropylammonium (TPA) is added to the mixed solution in a SiO ₂ / TPA molar ratio. To obtain an aqueous gel. Next, hydrothermal synthesis was performed using an aqueous gel under the conditions of 10 atm, 150 ° C. and 350 hours, and then the synthesized product was subjected to a calcination treatment to remove TPA to obtain ZSM-5 zeolite. SiO ₂ / Al ₂ O ₃ molar ratio of this ZSM-5 zeolite was 35.2.

The unmodified ZSM-5 zeolite was subjected to the following treatments to obtain the modified ZSM-5 of Examples 4 to 7.
A zeolite was obtained.

In Example 4, unmodified ZSM-5 zeolite was subjected to the same modification treatment as in Example 3. In Example 5, the wet ZSM-5 zeolite obtained by adding the same amount of pure water to the unmodified ZSM-5 zeolite was used.
It was held in an atmosphere of 00 ° C. for 3 hours and then subjected to the same modification treatment as in Example 3. Example 6 is unmodified Z
The obtained wet ZSM-5 zeolite prepared by adding the same amount of pure water to SM-5 zeolite was kept in an atmosphere of 500 ° C. for 3 hours, and then subjected to the same modification treatment as in Example 3 and thereafter The atmosphere maintenance and the modification treatment were repeated twice. Example 7 is a wet ZSM- obtained by adding the same amount of pure water to unmodified ZSM-5 zeolite.
5 zeolite was held in an atmosphere of 800 ° C. for 3 hours, then subjected to the same modification treatment as in Example 3, and thereafter, the atmosphere maintenance and the modification treatment were repeated twice.

Table 5 shows total Al abundances in Examples 4 to 7 and unmodified ZSM-5 zeolite, and Si content, Al content and Al in the fine pore forming part.
The presence rate A is shown.

[0037]

[Table 5] From Table 5, it can be seen that when the modifying treatment conditions are made severe, the Al abundance ratio A sharply decreases because the Al removal reaction in the fine hole forming portion is actively performed.

FIG. 8 shows the X-ray diffraction result of Example 4.

Each peak of the first crystal plane group having a lattice spacing of 4.0 Å or more appears at an angle 2θ of 2θ ≦ 22 °. Therefore, in the first crystal plane group, (101) plane / (01
1) plane, (200) plane / (020) plane, (102) plane,
The (301) plane, the (202) plane, and the (232) plane are included. Here, a plurality of crystal planes CF ₁ having Miller indices h, k, and 1 of 2 or less are (101) plane / (011)
Plane, (200) plane / (020) plane, (102) plane, (2
02) surface is applicable. These crystal planes CF ₁ are ZSM-
5 is a crystal plane due to the periodicity of the cavity structure peculiar to zeolite, and the crystal plane showing the maximum X-ray reflection intensity is (101) plane / (011) plane.

Each peak of the second crystal plane group having a lattice plane spacing of 3 Å or more and less than 4 Å has an angle 2θ of 22 ° <2θ ≦ 30.
Appearing in °, and therefore the second crystallographic group is (501)
Planes, (303) planes, and (133) planes are included. This second
Out of the crystal plane group, the crystal plane CF showing the maximum X-ray reflection intensity
_The (501) plane corresponds to 2. This (501) plane is
In ZSM-5 zeolite, it is a crystal plane resulting from a basic skeleton structure mainly composed of SiO ₄ tetrahedral structure portions.

9 to 11 show the results of the fifth to seventh embodiments.
Further, FIG. 12 shows the X-ray diffraction results of unmodified ZSM-5 zeolite. From FIG. 9 to FIG. 12, also in Examples 5 to 7 and unmodified ZSM-5 zeolite, the crystal plane showing the maximum X-ray reflection intensity among the crystal planes CF ₁ is the (101) plane / (011) plane. And the crystal plane C
It can be seen that F ₂ is the (501) plane.

Table 6 shows (101) face / (01) in Examples 4 to 7 and unmodified ZSM-5 zeolite.
1) X-ray reflection intensity I _{1 of the} surface, (50) in Example 4, etc.
1) X-ray reflection intensity I ₂ and both X-ray reflection intensity I ₁ of the surface represents the ratio I ₁ / I ₂ of I _2.

[0043]

[Table 6] From Table 6, in Examples 4 to 7, (101)
Plane / (011) plane X-ray reflection intensity I ₁ is unmodified ZSM-
It can be seen that the X-ray reflection intensity I ₂ of the (501) plane is almost the same as that of the unmodified ZSM-5 zeolite, as compared with the No. 5 zeolite, as the Al abundance ratio A decreases.

Examples 4 to 7 and unmodified ZSM-
5 Zeolites in air, heating temperature 600-1
A heat deterioration test was performed under the conditions of 100 ° C. and a heating time of 18 hours, and then powder X-ray diffraction was performed on Cu-Kα rays for Example 4 and the like to observe the state of crystal destruction by heat. 13 results were obtained.

In Table 7 and FIG. 13, the mark "○" indicates
The case where there is no change in the X-ray reflection intensity after the test is shown, and the mark "△" shows the case where the decrease rate of the X-ray reflection intensity after the test is less than 10%, and further "x".
The mark shows the case where the reduction rate of the X-ray reflection intensity after the test is 10% or more. FIG. 13 shows (200) plane / (02
The 0) plane is shown.

[0046]

[Table 7]As is clear from Tables 5 to 7 and FIG. 13, Example 4
In the case of Example 7, Al abundance A in the fine hole forming portion
Is A ≦ 15.8% and the ratio I₁/ I₂Is 0.76
≤I₁/ I₂Due to ≦ 1.10, heat resistant temperature
The temperature has improved to 1000 ° C. Unmodified ZSM-5 Zeo
In the case of light, the ratio I₁/ I₂Is I ₁/ I₂<0.
76 and the crystal plane CF₁Temperature limit due to poor crystallinity
Is low. [Example-III] In this example, as unmodified zeolite,
Unmodified ZSM-5 zeolite produced by a method such as
Was used.

First, colloidal silica and aluminum nitrate were mixed at a SiO ₂ / Al ₂ O ₃ molar ratio of 10 and tetrapropylammonium (T
PA) was mixed at a SiO ₂ / TPA molar ratio of 10 to obtain an aqueous gel. Then, using the aqueous gel,
Hydrothermal synthesis is performed under the conditions of 10 atm, 150 ° C. and 350 hours, and then the synthetic product is subjected to a baking treatment to remove TPA,
ZSM-5 zeolite was obtained. SiO ₂ / Al ₂ O ₃ molar ratio of this ZSM-5 zeolite was 10.

The unmodified ZSM-5 zeolite was subjected to the following treatment to obtain the modified ZSM-of Examples 8-11.
5 zeolite was obtained.

In Example 8, the normality of the 90 ° C. HCl solution was set to 0.1 N, and the 90 ° C. constant temperature holding time was 0.5.
The time is set and the unmodified ZSM-5 zeolite is modified. Example 9 is unmodified ZSM-5.
Wet ZSM-5 zeolite obtained by adding the same amount of pure water to zeolite was maintained in an atmosphere of 800 ° C. for 3 hours, and then subjected to the same modification treatment as in Example 3. Example 10 is an unmodified ZSM-5 zeolite,
The obtained wet ZSM-5 zeolite to which the same amount of pure water was added was kept in an atmosphere of 500 ° C. for 3 hours, then the same reforming treatment as in Example 3 was carried out, and thereafter, the atmosphere keeping and reforming treatment were carried out. Is repeated twice. Example 11
Is a wet ZSM-5 zeolite obtained by adding the same amount of pure water to unmodified ZSM-5 zeolite as 800
The sample was held in an atmosphere of ° C for 3 hours, then subjected to the same modification treatment as in Example 3, and thereafter, the atmosphere maintenance and the modification treatment were repeated twice.

Table 8 shows the total Al abundance in Examples 8 to 11, the comparative example and the unmodified ZSM-5 zeolite, and the Si content, Al content and Al abundance A in the fine pore forming portion, respectively. Show.

[0051]

[Table 8] From Table 8, when the modification treatment conditions are made severe, the Al removal reaction particularly in the fine hole forming portion is actively performed, and therefore Al
It can be seen that the existence rate A drops sharply.

Table 9 shows (101) face / (01) in Examples 8 to 11 and unmodified ZSM-5 zeolite.
1) X-ray reflection intensity I _{1 of the} surface, (50) in Example 8, etc.
1) The X-ray reflection intensity I _{2 of the} surface and the ratio I ₁ / I ₂ of both X-ray reflection intensities I ₁ and I ₂ are shown.

[0053]

[Table 9] From Table 9, in Examples 8 to 11, (10
1) plane / (011) plane X-ray reflection intensity I ₁ is unmodified ZS
It can be seen that the ratio A increases as the abundance ratio A of the M-5 zeolite decreases, while the X-ray reflection intensity I ₂ of the (501) plane is substantially the same as that of the unmodified ZSM-5 zeolite. .

Examples 8-11 and unmodified ZSM
For -5 zeolite, heating temperature in air is 600-
A thermal deterioration test was performed under the conditions of 1100 ° C. and a heating time of 18 hours, and then powder X-ray diffraction was performed on Cu-Kα rays for Example 8 and the like to observe the state of crystal destruction by heat. Got

In Table 10, "O" indicates that the X-ray reflection intensity did not change even after the test, and "X" indicates that the reduction rate of the X-ray reflection intensity after the test was 10% or more. It shows the case.

[0056]

[Table 10]As is clear from Tables 8 to 10, Examples 8 to 1
In the case of 1, the Al existence rate A in the fine hole forming portion is 0% ≦
A ≦ 15.8% and the ratio I₁/ I₂Is 0.76 ≦
I₁/ I₂Due to ≦ 1.10, heat resistant temperature
Has improved to 900 to 1000 ° C. Unmodified ZSM-
In the case of 5 zeolite, the ratio I₁/ I ₂Is I₁/ I₂
<0.76 and crystal plane CF₁Has poor crystallinity
Heat resistant temperature is low. B. Regarding Exhaust Gas Purifying Catalyst The catalyst in each example is a modified zeolite, and
Modified mordenite or modified ZSM-5 with heat resistance
Zeolite is used as a carrier, and metal Me for catalyst is applied to the carrier.
It is supported by the on-exchange method.

As the metal Me for the catalyst, Ib of the periodic table is used.
At least one metal selected from at least one group of the group consisting of iron, iron and platinum is used. Periodic table Ib
Cu, Ag and Au are included in the group, and F is included in the iron group.
e, Ni, Co, and platinum, Ru, R
h, Pd, Os, Ir and Pt are included.

14 and 15 show the ion exchange reaction.
FIG. 14 corresponds to the ion exchange reaction in the fine hole forming portion shown in FIG. 1 (c ₁ ), and FIG. 15 corresponds to the ion exchange reaction in the fine hole forming portion shown in FIG. 1 (c ₂ ).

When the carrier is put in a solution containing, for example, a divalent catalytic metal Me (ions) and kept at a predetermined temperature for a predetermined time, the formation of fine pores shown in FIGS. 14 (a) and 15 (a) is formed. In the part, an ion exchange reaction occurs between the chemically active H atom and the catalytic metal Me, and the ion exchange reaction occurs, as shown in FIGS.
As shown in (b), the catalytic metal Me is bonded to the position where the H atom was bonded. In this case, as shown in FIG. 14B, the catalytic metal Me may be bonded to the two non-shared O atoms of the SiO ₄ tetrahedral structure so as to bridge them.

The catalyst obtained by the ion exchange reaction has a large amount of the catalytic metal Me supported, and has excellent high temperature durability and a high exhaust gas purification rate.

FIG. 16 shows the ion exchange reaction of unmodified zeolite. In this case, in the fine hole forming portion shown in FIG. 16A, an ion exchange reaction occurs between the positive atom bonded to the negatively charged O atom of the AlO ₄ tetrahedral structure 3 and the catalyst metal Me. Then, as shown in FIG. 16B, the catalytic metal Me is bonded to the O atom.

14 (b) and 15 (b) and FIG.
Comparing with 6 (b), FIG.
4 (b) and FIG. 15 (b) show that the supported amount of the catalytic metal Me is larger than that in the case of FIG. 16 (b) using unmodified zeolite.

The supported amount of the catalytic metal Me may include not only the ion-exchanged amount but also the amount mechanically attached to the fine pores. [I] Nitric oxide gas (NO
Regarding the catalyst used for purification of x) [Example-I] Preparation of catalysts of Examples 1 to 6 Modified ZSM-5 of Example 4 in the above-mentioned section A [Example-II]
100 g of zeolite, 0.0125 mol each
/ Liter, 0.025mol / liter, 0.05mol
/ Liter, 0.1 mol / liter, 0.2 mol / liter and 0.3 mol / liter amine acetate copper solution 5
Ion exchange was carried out under the conditions of placing the mixture in 00 ml and leaving it at 50 ° C. for 18 hours. After the solid-liquid separation, the solid content is washed with pure water and then dried under the condition of 400 ° C. for 24 hours, and the modified ZSM-5 zeolite as the carrier is added to the catalyst metal Cu (divalent; ) Was carried by the ion exchange method to obtain the catalysts of Examples 1 to 6. The relationship between each example and each concentration of the amine acetate copper solution is that the catalysts of Examples 1 to 6 have a concentration of 0.0125 mol / liter to 0.3 mol /
Corresponds to each liter.

Table 11 shows the amount of supported Cu (g) per 100 g of the modified ZSM-5 zeolite in the catalysts of Examples 1 to 6.

[0065]

[Table 11] [Example-II] Preparation of catalysts of Examples 7 to 9 100 g of the modified mordenite of Example 3 in the section A [Example-I] was added at a concentration of 0.1 mol / liter, respectively.
Ion exchange was carried out by placing the mixture in 500 ml of 0.2 mol / liter and 0.3 mol / liter amine acetate copper solution and allowing it to stand at 50 ° C. for 18 hours. After solid-liquid separation, the solid content was washed with pure water, then dried at 400 ° C. for 24 hours, and the modified mordenite as a carrier was loaded with Cu as a catalyst metal by an ion exchange method. Example 7-
The catalyst of Example 9 was obtained. The relationship between each example and each concentration of the amine acetate copper solution corresponds to a concentration of the catalysts of Examples 7 to 9 of 0.1 mol / liter to 0.3 mol / liter, respectively.

Table 12 shows the amount of Cu supported (g) per 100 g of modified mordenite in the catalysts of Examples 7 to 9.
Indicates.

[0067]

[Table 12] [Example-III] Preparation of Catalysts of Comparative Examples 1 to 6 100 g of unmodified ZSM-5 zeolite in the above-mentioned A section [Example-II] was added to each of the concentrations of 0.0125 mol / liter, 0.025 mol / liter, and 0. Ion exchange was carried out under the conditions of standing at 50 ° C. for 18 hours, by charging into 500 ml of amine acetate copper solutions of 0.05 mol / liter, 0.1 mol / liter, 0.2 mol / liter and 0.3 mol / liter. After solid-liquid separation, the solid content is washed with pure water, and then dried under the condition of 400 ° C. for 24 hours, and the unmodified ZSM-5 zeolite as a carrier is mixed with Cu as a catalyst metal by an ion exchange method. The supported catalysts of Comparative Examples 1 to 6 were obtained. The relationship between each comparative example and each concentration of the amine acetate copper solution is that the catalysts of Comparative Examples 1 to 6 have a concentration of 0.0125 mol.
/ Liter to 0.3 mol / liter, respectively.

Table 13 shows the Cu loadings (g) per 100 g of unmodified ZSM-5 zeolite in the catalysts of Comparative Examples 1-6.

[0069]

[Table 13] [Example-IV] Preparation of catalysts of Comparative Examples 7 to 9 Unmodified mordenite 100 in the section A [Example-I]
g, 0.1 mol / liter, 0.2 mol, respectively
/ Liter and 0.3 mol / liter of amine acetate copper solution (500 ml), and ion exchange was performed under the conditions of standing at 50 ° C for 18 hours. After solid-liquid separation, the solid content is washed with pure water, then dried at 400 ° C. for 24 hours,
On the unmodified mordenite which is a carrier, C which is a metal for a catalyst is added.
Comparative Examples 7 to 9 in which u was supported by the ion exchange method
The catalyst was obtained. The relationship between each Example and each concentration of the amine acetate copper solution is that the catalysts of Comparative Examples 7 to 9 have a concentration of 0.1 mol.
/ Liter to 0.3 mol / liter, respectively.

Table 14 shows the amount of supported Cu (g) per 100 g of unmodified mordenite in the catalysts of Comparative Examples 7-9.

[0071]

[Table 14] [Example-V] Preparation of Catalysts of Comparative Examples 10 to 12 Comparative Example Modified Mordenite 1 in Section A [Example-I]
00g to a concentration of 0.1 mol / liter, 0.2
Ion exchange was carried out by placing the mixture in 500 ml of amine acetate copper solutions of mol / liter and 0.3 mol / liter, and allowing it to stand at 50 ° C. for 18 hours. After solid-liquid separation, the solid content is washed with pure water, and then dried under the condition of 400 ° C. for 24 hours so that Cu, which is a catalyst metal, is supported on the carrier, Comparative Example modified mordenite, by an ion exchange method. Comparative Example 10
~ A catalyst of Comparative Example 12 was obtained. The relationship between each comparative example and each concentration of the amine acetate copper solution corresponds to the catalysts of Comparative Examples 10 to 12 having a concentration of 0.1 mol / liter to 0.3 mol / liter, respectively.

Table 15 shows the amount of Cu supported (g) per 100 g of the modified mordenite of the comparative example in the catalysts of Comparative Examples 10 to 12.

[0073]

[Table 15] (A) Activity evaluation of catalyst The catalysts of Examples 1 to 6 (support: Example 4 modified ZSM-5 zeolite) described in [Example-I] and the comparative examples described in [Example-III] above. The following NOx purification tests were conducted on the catalysts of 1 to Comparative Example 6 (carrier: unmodified ZSM-5 zeolite).

The above test was conducted with the composition of 10% by volume O ₂ .
800ppm C ₃ H ₆ , 1200ppm NO, 1000ppm
CO, 10% by volume CO ₂ , 500 ppm H ₂ , 10% by volume
A test gas containing H ₂ O and the balance of N ₂ was introduced into a reaction vessel of an atmospheric pressure fixed bed filled with 20 g of a catalyst at a flow rate of 17500 ml.
/ Min and flow the test gas at room temperature
The temperature was raised to 500 ° C. at a temperature rising rate of 15 ° C./min, and the NOx purification rate was measured during this period.

For each catalyst, unmodified ZSM-5 Zeola
Al in Ito₂O₃Number of moles M ₁And modified ZSM
-5 number of moles of Cu supported on zeolite-5₂Ratio of₂
/ M ₁And the relationship between the NOx maximum purification rate and
16, the results shown in FIG. 17 were obtained.

Al in unmodified ZSM-5 zeolite
The mole number M ₁ of ₂ O ₃ was determined by the following method.

The unmodified ZSM-5 zeolite contains 5% by weight of H ₂ O and therefore the unmodified ZSM-zeolite.
5 The sum of the weights of SiO ₂ and Al ₂ O ₃ in 100 (g) of zeolite is 100 (g) -5 (g) = 95 (g).

Here, the weight of 1 mol of Al ₂ O ₃ is 10.
1.96 (g), the weight of 1 mol of SiO ₂ is 60.09
(G), since SiO ₂ / Al ₂ O ₃ molar ratio is 35.2, A in unmodified ZSM-5 zeolite 100g
The weight of l ₂ O ₃ is 95 × [101.96 / {(35.
2 × 60.09) +101.96}] = 4.37 (g)
Becomes

Therefore, the number of moles M ₁ of Al ₂ O ₃ in the unmodified ZSM-5 zeolite is M ₁ = 4.37 / 10.
1.96 = 0.043.

On the other hand, the number of moles M _{2 of} Cu supported on the modified ZSM-5 zeolite is such that the weight of 1 mole of Cu is 63.
55 (g), and since the amount of supported Cu per 100 g of modified or unmodified ZSM-5 zeolite is as shown in Tables 11 and 13, M ₂ = the amount of supported Cu (g) /63.55
Becomes

Therefore, the ratio M _{2 of} both molar numbers M ₁ and M ₂ is
/ M ₁ is M ₂ / M ₁ = (Cu loading amount / 63.55) /
0.043 = Cu supported amount / 2.73.

[0082]

[Table 16] FIG. 17 is a graph showing the relationship between the ratio M ₂ / M ₁ in Table 16 and the NOx maximum purification rate. In the figure, points (1) to (6) on the line v ₁ are those of Examples 1 to 1 Each of the catalysts of Example 6 corresponds to points (1) to (6) on the line v ₂ of Comparative Examples 1 to 3.
It corresponds to the catalyst of Comparative Example 6, respectively.

As is clear from Table 16 and FIG.
In the case where the ratios M ₂ / M ₁ are the same, Example 1
The NOx maximum purification rate of the catalyst of Example 6 is significantly improved and the activity thereof is higher than that of the catalysts of Comparative Examples 1 to 6. The catalysts of Examples 7 to 9 described in [Example-II] above (support: Example 3 modified mordenite), [Example-IV] above.
The catalysts of Comparative Examples 7 to 9 (carrier: unmodified mordenite) and the catalysts of Comparative Examples 10 to 12 (carrier: Comparative modified mordenite) described in [Example-V] are described above. A NOx purification test was conducted in the same manner as in, and the ratio M ₂ / M _{1 of the} number M ₁ of Al ₂ O _{3 in} the unmodified mordenite and the number M ₂ of Cu supported on the modified mordenite was measured for each catalyst, When the relationship with the NOx maximum purification rate was investigated, the results shown in Table 17 and FIG. 18 were obtained. Ratio M
₂ / M ₁ is SiO ₂ / Al ₂ O ₃ according to the above calculation method.
C in Table 12, Table 14 and Table 15 with the molar ratio of 16.6.
It was determined from the amount of u supported / 5.49.

[0084]

[Table 17] FIG. 18 is a graph showing the relationship between the ratio M ₂ / M ₁ in Table 17 and the NOx maximum purification rate. In the figure, points (7) to (9) on the line w ₁ are the results of Examples 7 to 7. Each of the catalysts of Example 9 corresponds to points (7) to (9) on the line w ₂ , and Comparative Examples 7 to
Each corresponds to the catalyst of Comparative Example 9, and points (10) to (12) on the line w ₃ correspond to the catalysts of Comparative Example 10 to Comparative Example 12, respectively.

As is clear from Table 17 and FIG.
In the case where the ratios M ₂ / M ₁ are the same, Example 7
The catalysts of Example 9 have a significantly improved NOx maximum purification rate and are highly active as compared with the catalysts of Comparative Examples 7 to 12. (B) Evaluation of heat resistance of catalyst Catalyst of Example 5 (carrier: modified ZSM-5 zeolite of Example 4) and catalyst of Comparative Example 5 (carrier: unmodified ZSM)
-5 zeolite) was left in the atmosphere at a temperature of 500 to 800 ° C. for 18 hours, then cooled, and then the flow rate of the test gas was changed to 25500 ml / min to remove NOx by the same method as described above. When the test was conducted and the maximum NOx purification rate of each catalyst was measured, the results shown in Table 18 and FIG. 19 were obtained. In Table 18 and FIG.
"Unheated" means that the catalysts of Example 5 and Comparative Example 5 prepared in [Example-I] and [Example-III] were not placed in the heating atmosphere.

[0086]

[Table 18] FIG. 19 is a graph showing the relationship between the atmospheric temperature and the maximum NOx purification rate in Table 18, in which the line x ₁ is the catalyst of Example 5 and the line x ₂ is the catalyst of Comparative Example 5, respectively. Applicable

As is clear from Table 18 and FIG.
In the unheated state and each atmosphere temperature, the catalyst of Example 5 has better heat resistance than the catalyst of Comparative Example 5. In particular, the catalyst of Example 5 maintains its initial activity up to an ambient temperature of 600 ° C., and even at an ambient temperature of 700 ° C., it has substantially the same activity as the unheated catalyst shown by the line x ₂ . The activity of the catalyst of Comparative Example 5 decreases proportionally as the atmospheric temperature rises. The catalyst of Example 8 (carrier: modified mordenite of Example 3), the catalyst of Comparative Example 8 (carrier: unmodified mordenite) and the catalyst of Comparative Example 11 (carrier: modified mordenite of Comparative Example) were heated at room temperature in the atmosphere. 1 in an atmosphere of 500-700 ° C
After leaving it to stand for 8 hours and then cooling it, a NOx purification test was conducted by the same method as described above (flow rate of test gas: 25,500 ml / min), and the maximum NOx purification rate of each catalyst was measured. Got the result. In Table 19 and FIG. 20, “no heating” means the catalysts of Example 8, Comparative Example 8 and Comparative Example 11 prepared in the above [Example-II], [Example-IV] and [Example-V]. It means not placed in the heating atmosphere.

[0088]

[Table 19] FIG. 20 is a graph showing the relationship between the atmospheric temperature and the NOx maximum purification rate in Table 19, in which the line y ₁ is the catalyst of Example 8 and the line y ₂ is the catalyst of Comparative Example 8. Further line y ₃
Correspond to the catalyst of Comparative Example 11, respectively.

As is clear from Table 19 and FIG.
The catalyst of Example 8 has higher high temperature durability than the catalysts of Comparative Example 8 and Comparative Example 11 in the non-heated state and each atmosphere temperature. In particular, the catalyst of Example 8 has substantially the same activity as the unheated catalyst shown by the line y ₂ even at the ambient temperature of 700 ° C. [II] Mainly hydrocarbon gas (HC) in exhaust gas
Regarding the catalyst used for purification of the catalyst of Example 10, 80 g of the modified ZSM-5 zeolite of Example 4 in the section A [Example-II] was loaded with 3 g of Pd by an impregnation method. The catalyst of Example 11 was obtained by supporting 3 g of Pd on 80 g of the heat-resistant modified mordenite of Example 3 in the section A [Example-I] by an impregnation method.

For the catalysts of Example 10 and Example 11, the following HC purification test was conducted, and H
When the C purification rate was measured, the results shown in FIG. 21 were obtained.

The test shows that the composition is 0.5% by volume.
O₂, 400ppm C₃H₆, 500ppm NO, 0.5 body
Product% CO, 14 volume% CO₂, 0.17% by volume H₂And
And balance N ₂20g of catalyst with test gas
Flow into the fixed-pressure fixed-bed reaction tube at a flow rate of 25,000 ml / min.
Pass the test gas at room temperature to 400 ° C.
At a heating rate of 12 to 12.5 ° C / min during
It was carried out by measuring the HC purification rate of.

In FIG. 21, the line z ₁ corresponds to the catalyst of Example 10, and the line z ₂ corresponds to the catalyst of Example 11. It can be seen from FIG. 21 that both catalysts have a high HC purification rate. In particular, both catalysts have exhaust gas temperatures of 140-180.
In the low temperature range of ℃, a catalyst using unmodified ZSM-5 zeolite (for example, at a gas temperature of 140 ℃, HC purification rate of about 4
0%) and a catalyst using unmodified mordenite (for example, the HC purification rate is about 25% at a gas temperature of 140 ° C.), and the HC purification rate is improved.

In each of the above examples, the crystalline aluminosilicate is obtained by subjecting the unmodified zeolite to the modification treatment, but the crystalline aluminosilicate according to the present invention can be synthesized. .

[0094]

According to the inventions of claims 1 to 3, by specifying the crystal structure as described above, it is possible to provide a crystalline aluminosilicate having excellent heat resistance.

According to the fifth to seventh aspects of the present invention, there is provided a catalyst comprising a crystalline aluminosilicate having heat resistance and a catalyst metal, which has high temperature durability and a high exhaust gas purification rate. be able to.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a deAl reaction of unmodified zeolite.

2 is an X-ray diffraction diagram of modified mordenite of Example 1. FIG.

3 is an X-ray diffraction diagram of modified mordenite of Example 2. FIG.

4 is an X-ray diffraction diagram of modified mordenite of Example 3. FIG.

FIG. 5 is an X-ray diffraction diagram of modified mordenite of Comparative Example.

FIG. 6 is an X-ray diffraction pattern of unmodified mordenite.

FIG. 7 is a graph showing the relationship between the X-ray reflection intensity of the (200) plane and the heating temperature.

8 is an X-ray diffraction diagram of modified ZSM-5 zeolite of Example 4. FIG.

9 is an X-ray diffraction pattern of modified ZSM-5 zeolite of Example 5. FIG.

10 is an X-ray diffraction pattern of modified ZSM-5 zeolite of Example 6. FIG.

11 is an X-ray diffraction pattern of modified ZSM-5 zeolite of Example 7. FIG.

FIG. 12 is an X-ray diffraction pattern of unmodified ZSM-5 zeolite.

FIG. 13 is a graph showing the relationship between the X-ray reflection intensity of the (200) plane / (020) plane and the heating temperature.

FIG. 14 is an explanatory diagram showing an example of an ion exchange reaction in a fine pore forming part of modified zeolite.

FIG. 15 is an explanatory view showing another example of the ion exchange reaction in the fine pore forming part of the modified zeolite.

FIG. 16 is an explanatory diagram showing an example of an ion exchange reaction in a fine pore forming part of unmodified zeolite.

FIG. 17: Al ₂ O ₃ mole number M ₁ and Cu mole number M ₂
3 is a graph showing an example of the relationship between the ratio M ₂ / M _{1 of} and the maximum NOx purification rate.

FIG. 18: Number of moles M ₁ of Al ₂ O ₃ and number of moles M _{2 of} Cu M ₂
7 is a graph showing another example of the relationship between the ratio M ₂ / M ₁ and the maximum NOx purification rate.

FIG. 19 is a graph showing an example of the relationship between the atmospheric temperature and the NOx maximum purification rate.

FIG. 20 is a graph showing another example of the relationship between the ambient temperature and the NOx maximum purification rate.

FIG. 21 is a graph showing the relationship between gas temperature and HC purification rate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoki Sugiyama 1-4-1 Chuo, Wako-shi, Saitama Stock Research Institute Honda Technical Research Institute

Claims (9)

[Claims] 1. In the first crystal plane group having a lattice spacing of 4.0 Å or more, Miller indices h, k, and l are 2 respectively.
Among a plurality of crystal planes CF ₁ below, the X-ray reflection intensity I _{1 of the} crystal plane showing the maximum X-ray reflection intensity and the lattice plane spacing of 3
The maximum X of the second crystal plane group that is Å or more and less than 4 Å
Crystalline aluminosilicates ratio I ₁ / I ₂ of the X-ray reflection intensity I ₂ of the crystal plane CF ₂ showing the line reflection intensity is characterized in that it is a _{0.76 ≦ I 1 / I 2 ≦} 1.10 . 2. The micropore forming part in the skeletal structure has a plurality of SiO ₄ tetrahedral structure parts and one or more AlO ₄ tetrahedral structure parts which are bonded to each other by sharing O atoms. the SiO ₄ tetrahedron structure, contains SiO ₄ tetrahedral structure with non covalent O atoms are separated from the SiO ₄ tetrahedral structures adjacent, chemically active positive atoms in the non-covalent O atoms A crystalline aluminosilicate characterized in that one of the positive group and the positive group is bonded, and the abundance A of Al atoms in the fine pore forming part is set to A ≦ 15.8%. 3. The fine pore forming portion in the skeletal structure is an O source.
A plurality of SiOs sharing a child and bonded to each other_FourTetrahedral structure
It has a structure part and those SiO_FourAdjacent to the tetrahedral structure
SiO_FourUnshared O atom separated from tetrahedral structure
With SiO _FourA non-shared O source including a tetrahedral structure
One of the chemically active positive atoms and positive groups is attached to the child.
A crystalline aluminosilicate characterized in that 4. Modified mordenite and modified ZSM-5.
The crystalline aluminosilicate according to claim 1, which is one of zeolites. 5. In the first crystal plane group having a lattice spacing of 4.0 Å or more, Miller indices h, k, and l are 2 respectively.
Among a plurality of crystal planes CF ₁ below, the X-ray reflection intensity I _{1 of the} crystal plane showing the maximum X-ray reflection intensity and the lattice plane spacing of 3
The maximum X of the second crystal plane group that is Å or more and less than 4 Å
A crystalline aluminosilicate ratio I ₁ / I ₂ is _{0.76 ≦ I 1 / I 2 ≦} 1.10 in an X-ray reflection intensity I ₂ of the crystal plane CF ₂ showing the line reflection intensity, the crystalline A metal for catalyst supported on an aluminosilicate, wherein the metal for catalyst is at least one metal selected from at least one group selected from Group Ib, the iron group and the platinum group of the periodic table, Exhaust gas purification catalyst. 6. The micropore forming part in the skeleton structure has a plurality of SiO ₄ tetrahedral structure parts and one or more AlO ₄ tetrahedral structure parts which are bonded to each other by sharing O atoms. the SiO ₄ tetrahedron structure, contains SiO ₄ tetrahedral structure with non covalent O atoms are separated from the SiO ₄ tetrahedral structures adjacent, the presence of the Al atoms in the micropore forming portion a Is composed of a crystalline aluminosilicate set to A ≦ 15.8% and a catalytic metal supported on the crystalline aluminosilicate, wherein the catalytic metal is Group Ib of the periodic table, iron. An exhaust gas purifying catalyst, which is at least one metal selected from at least one group selected from the group consisting of platinum group and platinum group. 7. The fine pore forming portion in the skeletal structure is O
A plurality of SiOs sharing a child and bonded to each other_FourTetrahedral structure
It has a structure part and those SiO_FourAdjacent to the tetrahedral structure
SiO_FourUnshared O atom separated from tetrahedral structure
With SiO _FourCrystalline Al containing tetrahedral structure
Supported on minosilicate and its crystalline aluminosilicate
And a catalyst metal, the catalyst metal is
Table At least one of Group Ib, Iron and Platinum
Characterized by being at least one metal selected from
Exhaust gas purification catalyst. 8. The crystalline aluminosilicate is a modified crystalline aluminosilicate obtained by subjecting an unmodified crystalline aluminosilicate to a modification treatment, and the catalyst metal is the modified metal. The crystalline aluminosilicate is supported by application of an ion exchange method, and the number of moles of Al ₂ O ₃ in the unmodified crystalline aluminosilicate is M ₁ , and the modified crystalline aluminosilicate is supported. when has been the number of moles of the catalytic metal and M _2, the ratio of the two moles M _1, M ₂ M
₂ / M _{1 is, 0.06 ≦ M 2 / M 1} ≦ 2.1 is set to claim 5, 6 or 7 exhaust gas purifying catalyst according. 9. The exhaust gas purifying catalyst according to claim 5, 6, 7 or 8, wherein the modified crystalline aluminosilicate is one of modified mordenite and modified ZSM-5 zeolite.