JP2004167414A - Catalyst for synthetic gas generation and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce a catalyst for synthetic gas generation which is highly active and has a long serviceable life, and also provide a production method for the catalyst for the synthetic gas generation which enables the yield of the catalyst at a lower cost with a good productivity. <P>SOLUTION: The catalyst for the synthetic gas generation reforms a natural gas mainly composed of methane and enables the generation of the synthetic gas composed of hydrogen and carbon monooxide and then carries an active metal 12 on a surface part of a wall or within the wall of the base material as a honeycomb type base material 11 to be a sintered body of material powder. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a synthesis gas generating catalyst and a method for producing the same, and more particularly to a catalyst used for reforming natural gas containing methane as a main component to produce a synthesis gas composed of hydrogen and carbon monoxide, and a method for producing the same. It is about the method.
[0002]
[Prior art]
In recent years, there has been a movement to increase the use of natural gas from the viewpoints of global warming prevention, environmental protection, and abundant reserves. Until now, natural gas has been mainly used as a fuel for home and power generation, and other than that, it has been used for the synthesis of ammonia and methanol as a chemical raw material or for the hydrorefining of petroleum products. there were.
Natural gas is expected to become more and more important in the future, such as chemical feedstock, hydrogen feedstock for fuel cells, and hydrogen feedstock for hydrogen stations in the future where hydrogen infrastructure will be developed. . Therefore, development of a process capable of reforming natural gas into a reformed gas containing hydrogen with high efficiency and at low cost is desired.
[0003]
As a process for producing a synthesis gas (mixed gas of H ₂ and CO) from a natural gas containing methane as a main component using a catalyst, there are mainly two processes described below.
(1) Steam reforming method (CH ₄ + H ₂ O → CO + 3H ₂ ΔH = 206 kJ / mol)
{Circle around (2)} catalytic partial oxidation method (CH ₄ + ／ O ₂ → CO + 2H ₂ ΔH = −36 kJ / mol);
[0004]
[Problems to be solved by the invention]
By the way, in the steam reforming method (1), an inexpensive pellet-type Ni-based catalyst is used as a highly active catalyst and has already been put to practical use, but the steam reforming method (1) is an endothermic reaction. For this reason, a large amount of heat must be supplied from the outside, and there has been a problem that a large amount of energy is required to generate H ₂ and CO. Further, since the heat transfer of heat supply is rate-determining, it has been difficult to increase the size of the apparatus. Furthermore, since the reaction rate is low, a large-sized device (catalyst) was required as compared with the amount of synthesis gas to be produced. These have made the synthesis gas expensive.
[0005]
On the other hand, since the contact partial oxidation method of (2) is an exothermic reaction, a large amount of external heat supply is not required when H ₂ and CO are generated. Further, since the reaction rate is several orders of magnitude or more faster than (1), it is said that the size of the apparatus can be significantly reduced depending on the catalyst used.
[0006]
In the contact partial oxidation method (2), a noble metal (ruthenium (Ru), rhodium (Rh), etc.) catalyst is used as a highly active catalyst. Examples of the shape of the catalyst include a pellet type, a fluidized bed type, and a honeycomb type. Among them, the honeycomb type catalyst has the most effective catalyst shape in a small device because the pressure loss can be reduced. one of.
[0007]
As shown in FIG. 5, a honeycomb type catalyst generally has a porous layer made of alumina powder, cerium oxide or the like on a surface of a honeycomb type base material 51 made of cordierite (2MgO.2Al ₂ O ₃ .5SiO ₂ ) or stainless steel. (Wash coat layer) 52 is formed, and as shown in FIG. 7, the active metal (Ru, Rh, etc.) 71 is supported on the surface of the wash coat layer 52 (coating method). However, in this coating method, the concentration of the supported active metal 71 is high only at the surface portion of the substrate wall, as shown in FIG. 6, and a sufficient degree of dispersion of the active metal 71 cannot be obtained during the synthesis reaction. There was a problem. As a result, sufficient activity and life were not obtained.
[0008]
An object of the present invention, which has been made in view of the above circumstances, is to provide a highly active and long-lived catalyst for syngas generation.
[0009]
On the other hand, another object of the present invention is to provide a method for producing a highly active, long-lived catalyst for syngas generation with good productivity and at low cost.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a synthesis gas generating catalyst according to the present invention is a catalyst for reforming natural gas containing methane as a main component and generating a synthesis gas composed of hydrogen and carbon monoxide. An active metal is supported on the surface of the base material wall and inside the base material wall of a honeycomb-type base material that is a fired body. In addition, a catalyst for reforming natural gas containing methane as a main component and producing a synthesis gas consisting of hydrogen and carbon monoxide is extruded into a honeycomb shape using a kneaded mixture of raw material powder and an organic binder. An active metal is supported on the surface of the base material wall and the inside of the base material wall of the honeycomb-type base material obtained by firing the extruded body.
[0011]
More specifically, as shown in claim 3, the honeycomb substrate has a porous shape, and contains mesopores between the raw material powders and the organic binder removed by firing. It has macropores by gas.
[0012]
Further, as described in claim 4, the active metal is supported on the surface of the raw material powder facing the macropores and the raw material powder in the vicinity of the raw material powder.
[0013]
Further, as described in claim 5, the amount of active metal carried per liter of bulk volume of the honeycomb substrate is 0.1 to 4 g / l.
[0014]
Further, as described in claim 6, the main component of the honeycomb substrate is a simple substance of alumina, cerium oxide, or zirconium oxide, or a composite oxide obtained by combining two or more of them.
[0015]
As a result, the active metal-supporting surface area can be increased, and a highly active and long-lasting catalyst for syngas generation can be obtained.
[0016]
On the other hand, the method for producing a synthesis gas producing catalyst according to the present invention is a method for producing a synthesis gas comprising hydrogen and carbon monoxide by reforming natural gas containing methane as a main component. After mixing and kneading the organic binder with the raw material powder containing the powder as a main component, and extruding the mixture into a honeycomb shape using the kneaded product, the extruded product is subjected to a calcination treatment to obtain a honeycomb-type base material. After dipping the honeycomb substrate in an aqueous solution containing active metal ions, the honeycomb substrate is again subjected to a baking treatment so that the active metal is supported on the surface of the substrate wall of the honeycomb substrate and inside the substrate wall.
[0017]
Specifically, an organic binder such as a methylcellulose-based binder is mixed with the raw material powder, which is a mixture of alumina powder and cerium nitrate.
[0018]
Further, as set forth in claim 9, an organic binder such as a methylcellulose-based binder is mixed with the raw material powder composed of a simple substance of alumina powder, cerium nitrate, or zirconium nitrate, or a mixture of two or more of them. I do.
[0019]
As a result, a highly active and long-lived catalyst for syngas generation can be obtained with good productivity and at low cost.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.
[0021]
FIG. 1 is a partial cross-sectional view of the synthesis gas generating catalyst according to the present invention, FIG. 2 is an enlarged view of a main part A of FIG. 1, and FIG. 3 is an enlarged view of a main part B of FIG.
[0022]
As shown in FIG. 1, the synthesis gas generating catalyst according to the present invention is obtained by supporting an active metal 12 on a honeycomb substrate 11 which is a fired body of raw material powder. Here, as shown in FIG. 2, the active metal 12 covers the entire thickness direction (the left-right direction in FIG. 2) of the inside of the base material wall as well as the surface of the base material wall of the honeycomb-type base material 11. It is carried.
The concentration of the active metal 12 supported is slightly higher on the surface of the substrate wall than on the center of the substrate wall.
[0023]
More specifically, the honeycomb substrate 11 is formed by extruding a kneaded mixture of raw material powder and an organic binder into a honeycomb shape, and firing the extruded body, and is a porous material. As shown in FIG. 3, there are mesopores 32 between the raw material powders 31 and macropores 33 due to degassing of an organic binder (not shown) during firing. The active metal 12 is supported on the surface of the base material wall of the honeycomb base material 11, the raw material powder 31 facing the macropores 33, and the surface of the raw material powder 31 near them. In other words, the active metal 12 is applied to the surface of the base material wall of the honeycomb-shaped base material 11 and to the contact portion of the raw material powder group 35 with the outside air (the outer surface of the raw material powder group 35 and its vicinity). Carried on the surface.
[0024]
The raw material powder 31 is made of a simple substance of alumina powder, cerium nitrate, or zirconium nitrate, or a mixture of two or more of them. The main components of the honeycomb substrate 11 are alumina, cerium oxide. It is a simple oxide of (ceria) or zirconium oxide (zirconia), or a composite oxide obtained by combining two or more of them.
[0025]
The supporting amount of the active metal 12 per liter of bulk volume of the honeycomb substrate 11 is 0.1 to 4 g / l, preferably 0.5 to 2 g / l, and particularly preferably about 1 g / l. Here, the active metal 12 is not particularly limited, and any metal that is conventionally used for a honeycomb catalyst can be applied, and examples thereof include Ru and Rh. Particularly preferred is Ru.
[0026]
The wall thickness of the substrate wall in the honeycomb substrate 11 is determined by the size of the substrate 11 and the number of cells (cpsi [cell per square inch]), and has a thickness that can maintain the strength as a catalyst. If so, there is no particular limitation. However, since the active metal 12 is supported even inside the base material wall, it is preferably thinner if possible, for example, 0.1 to 1.0 mm, preferably 0.1 to 0.4 mm, and particularly preferably about 0.25 mm. It is.
[0027]
Next, the operation of the synthesis gas generating catalyst according to the present invention will be described with reference to the accompanying drawings.
[0028]
Since the catalytic partial oxidation is an exothermic reaction, the catalyst temperature increases during the synthesis reaction. At this time, in the conventional synthesis gas generation catalyst shown in FIGS. 5 to 7, the active metal 71 is supported only on the surface portion of the wash coat layer 52 formed on the surface of the honeycomb substrate 51. The surface area of the coat layer 52 is the surface area of the carrier as it is. That is, in the conventional catalyst, the surface area of the carrier (wash coat layer 52) was small. For this reason, it is difficult to keep the dispersion degree of the active metal 71 high, and sintering of the active metal 71 and the carrier occurs during the synthesis reaction. As a result, agglomeration of the active metal 71 occurs, causing a reduction in activity and a reduction in catalyst life. In addition, since the synthesis reaction occurs only at the surface of the carrier, if local heat is generated at the interface between the carrier and the active metal 71, in the worst case, the active metal 71 and the washcoat layer 52 may be peeled off. Was.
[0029]
On the other hand, the synthesis gas generating catalyst according to the present invention has the mesopores 32 and the macropores 33 inside the honeycomb substrate 11, and the surface portion of the substrate wall of the substrate 11. In addition, the contact portion between the inside of the base material wall and the outside air serves as a carrier, and is characterized in that the surface area of the carrier is large (eg, about 100 to 200 m ² / g). In the catalyst according to the present invention, unlike the conventional catalyst obtained by the coating method, the active metal 12 is dispersed and supported on the entire honeycomb substrate 11 (surface portion and inside the substrate wall). Is large.
[0030]
Therefore, in the catalyst according to the present invention, the dispersion degree of the active metal 12 can be increased even if the supported amount (absolute amount) of the active metal 12 is the same as that of the conventional catalyst by the coating method. Therefore, during the synthesis reaction, aggregation due to sintering of the active metal 12 can be suppressed. As a result, high activity can be obtained even in a reaction at a high temperature, and the life of the catalyst can be significantly improved.
[0031]
In addition, since the catalyst according to the present invention has a large surface area on which the active metal 12 is supported, local heat generation hardly occurs at the interface between the honeycomb substrate 11 and the active metal 12 during the synthesis reaction. Accordingly, it is possible to suppress the occurrence of sintering itself in the active metal 12 and the honeycomb substrate 11 during the synthesis reaction.
[0032]
In addition, the catalyst according to the present invention has a higher activity than the conventional catalyst when the supported amount of the active metal 12 is the same as the conventional catalyst. A smaller amount of the active metal 12 is required than the catalyst (or the size of the catalyst itself is smaller than the conventional catalyst). For this reason, the raw material cost of expensive active metals can be reduced, and the production cost of the synthesis gas generating catalyst can be reduced.
[0033]
Further, by applying the catalyst according to the present invention to a synthesis gas production plant, it becomes possible to significantly reduce the size of the catalyst as compared with a conventional catalyst with respect to the amount of synthesis gas to be produced. Further, by applying the catalyst according to the present invention to a synthesis gas production plant, synthesis gas can be produced with high efficiency. As a result, it is possible to obtain a plant capable of producing a large amount of synthesis gas with high efficiency while having a compact apparatus configuration. As a result, the production cost of synthesis gas can be reduced.
[0034]
Next, a method for producing a synthesis gas generating catalyst according to the present invention will be described.
[0035]
An organic binder such as a methylcellulose-based organic binder is mixed with a raw material powder that is a mixture of alumina powder and cerium nitrate and kneaded well. At the time of this kneading, a dispersant or a plasticizer may be appropriately added. As the organic binder, besides methylcellulose, carboxycellulose, PVA (polyvinyl alcohol), starch and the like can be used. In addition to the above combination, the raw material powder may be composed of a simple substance of alumina powder, cerium nitrate, or zirconium nitrate, or a mixture of two or more of them.
[0036]
Next, a honeycomb-shaped molded product is extruded using the kneaded product. After the obtained extruded product is dried, it is subjected to a baking treatment to form a honeycomb substrate made of a mixed oxide of alumina and cerium oxide.
[0037]
Next, the obtained honeycomb substrate is immersed in an aqueous solution containing active metal ions, for example, an aqueous ruthenium chloride n-hydrate (RuCl ₃ .nH ₂ O) solution, and then the moisture is dried.
[0038]
Thereafter, the dried honeycomb substrate is subjected to a baking treatment, and an active metal is supported on the surface and inside of the substrate wall of the honeycomb substrate to obtain the synthesis gas generating catalyst according to the present invention. Here, it is preferable that the honeycomb-type base material after the firing treatment is subjected to a reduction treatment by raising the temperature to 200 to 600 ° C., for example, 500 ° C. in a nitrogen gas containing 5% by volume of hydrogen.
[0039]
In the conventional manufacturing method using the above-described coating method, in order to uniformly form a wash coat layer (carrier) made of alumina powder, cerium oxide, etc. on the surface of the honeycomb-type substrate, the honeycomb-type substrate is made of alumina powder. It is necessary to sufficiently repeat the steps of immersing the honeycomb base material in a slurry containing cerium nitrate and cerium nitrate and the step of removing the honeycomb base material from the slurry and removing the excess slurry. On the other hand, in the production method according to the present invention, since a honeycomb-type base material made of an extruded product is used, a carrier made of alumina, cerium oxide, or the like, which is uniform in principle, can be obtained. That is, the operation for manufacturing the honeycomb-type base material is easy, and the uniform honeycomb-type base material can be used to manufacture a uniform honeycomb-type catalyst. As a result, the manufacturing cost can be reduced and the production cost can be reduced. Performance can be improved.
[0040]
That is, according to the production method according to the present invention, it is possible to produce a synthesis gas generating catalyst with good productivity and at low cost as compared with the conventional production method.
[0041]
As described above, the embodiments of the present invention are not limited to the above-described embodiments, and it is needless to say that various other embodiments are also possible.
[0042]
【Example】
Next, the present invention will be described based on examples, but the present invention is not limited to these examples.
[0043]
(Example 1)
Methyl cellulose as an organic binder is mixed with a raw material powder, which is a mixture of 750 g of alumina powder and 250 g of cerium nitrate hexahydrate (Ce (NO ₃ ) ₂ .6H ₂ O), and sufficiently stirred in a kneader. Was. At the time of kneading, glycerin, ceramisol (manufactured by NOF Corporation), and cellosol (manufactured by Chukyo Oil & Fat) were added in appropriate amounts. About 300 cc of ion-exchanged water was added little by little while stirring the kneader. Finally, kneading is performed for 4 hours to prepare a kneaded product for extrusion molding.
[0044]
Next, using this kneaded material, a honeycomb-shaped molded product having a cell number of 400 cpsi and a wall thickness of about 0.25 mm is extruded. The obtained extruded product was gradually dried in a dryer while gradually raising the temperature to 80 ° C., and then calcined at 800 ° C. for 3 hours in the air to obtain a mixed oxide of alumina and cerium oxide. To form a honeycomb substrate. This honeycomb substrate is cut into a length of 10 mm × a width of 10 mm × a length of 20 mm to form a honeycomb test piece.
[0045]
Next, the obtained test piece is immersed in an aqueous solution (ruthenium chloride concentration: 0.05 g / cc) of ruthenium chloride · n hydrate (RuCl ₃ .nH ₂ O), taken out and dried. . This operation is repeated until the Ru carrying amount becomes about 1 g / l.
[0046]
Next, the Ru-supporting honeycomb substrate was subjected to a baking treatment at 500 ° C. × 1 hr in the air. The honeycomb-type base material after the calcination treatment is subjected to a reduction treatment by raising the temperature to 500 ° C. in a nitrogen gas containing 5% by volume of hydrogen, and a Ru-supporting honeycomb type catalyst for syngas generation according to the present invention. Make a catalyst.
[0047]
(Conventional example 1)
A 10 mm long by 10 mm wide by 20 mm long honeycomb test piece made of cordierite is formed.
[0048]
Next, a slurry, which is a mixture of 5 g of alumina powder, 10 g of aluminum hydroxide (Al (OH) ₃ ), 30 cc of ion-exchanged water, and 0.5 cc of nitric acid, was placed in a container placed in an ultrasonic cleaner. Immerse the honeycomb test piece in it and shake well. Thereafter, the honeycomb test piece is taken out of the slurry, and excess slurry is blown off with high-pressure air. Thereafter, the honeycomb test piece is sufficiently dried in a dryer at 120 ° C. This operation is repeated until the amount of alumina carried becomes about 20 g / l. Finally, a baking treatment is performed at 800 ° C. for 3 hours in the atmosphere to form an alumina-supporting honeycomb-type base material.
[0049]
Next, the alumina-supported honeycomb-type substrate was immersed in a cerium nitrate aqueous solution which was a mixture of about 15 g of cerium nitrate hexahydrate (Ce (NO ₃ ) ₂ .6H ₂ O) and 200 cc of ion-exchanged water. Take out and dry the water. This operation is repeated until the supported amount of cerium oxide (CeO ₂ ) becomes about 5 g / l. Finally, a firing treatment at 700 ° C. for 3 hours is performed in the air to form a cerium oxide / alumina-supported honeycomb-type base material.
[0050]
Next, the cerium oxide / alumina-supported honeycomb type substrate was immersed in an aqueous solution of ruthenium chloride n-hydrate (RuCl ₃ .nH ₂ O) (ruthenium chloride concentration: 0.05 g / cc), and then taken out. Let the water dry. This operation is repeated until the Ru carrying amount becomes about 1 g / l.
[0051]
Next, the Ru / cerium oxide / alumina-supported honeycomb type substrate was subjected to a baking treatment at 500 ° C. × 1 hr in the air. The honeycomb test piece after the calcination treatment is heated to 500 ° C. in a nitrogen gas containing 5% by volume of hydrogen and subjected to a reduction treatment to produce a Ru-supported honeycomb catalyst.
[0052]
(Conventional example 2)
Instead of cerium nitrate hexahydrate (Ce (NO ₃ ) ₂ .6H ₂ O), zirconium nitrate (ZrO (NO ₃ ) ₂ .2H ₂ O) is used, and zirconium oxide is used as a honeycomb-type substrate after final firing. A Ru-supported honeycomb-type catalyst was produced in the same manner as in Conventional Example 1 except that a / alumina-supported honeycomb-type base material was formed.
[0053]
The catalytic activity of each of the honeycomb catalysts of Example 1 and Conventional Examples 1 and 2 was evaluated. The method of evaluation was such that after disposing each honeycomb-type catalyst in a reaction tube made of quartz glass, glass wool was filled between the reaction tube and the honeycomb-type catalyst so that the reaction gas did not flow around the honeycomb-type catalyst. . The composition of the reaction gas was a mixture of 50% methane (CH ₄ ) and 50% air as an oxidizing agent. The GHSV of the reaction gas was set to about 20,000 (1 / hr), the temperature of the catalyst was increased stepwise from about 100 ° C. to 900 ° C., and CH at each reaction temperature (average temperature of the upstream side temperature and the downstream side temperature) was changed. _The catalytic activity was evaluated by _four conversions. Here, since the ratio of CH ₄ to air in the reaction gas is 1: 1, the maximum value of the CH ₄ conversion is 40%.
[0054]
FIG. 4 shows the relationship between the reaction temperature and the methane conversion in each of the honeycomb catalysts of Example 1 and Conventional Examples 1 and 2.
[0055]
As shown in FIG. 4, in the honeycomb catalyst of Example 1, the CH ₄ conversion reached 40% at a little over 700 ° C. On the other hand, in the honeycomb catalysts of Conventional Examples 1 and 2, the CH ₄ conversion reaches 40% at about 820 to 850 ° C. From this, in the case of the honeycomb catalyst of Example 1, the activation temperature is lower than that of the honeycomb catalysts of Conventional Examples 1 and 2 by 100 ° C. or more. That is, it can be seen that the honeycomb catalyst of Example 1 can obtain higher activity even at a lower reaction temperature than the honeycomb catalysts of Conventional Examples 1 and 2.
[0056]
【The invention's effect】
In short, according to the present invention, the following excellent effects are exhibited.
(1) The active metal supporting surface area can be increased, and a highly active and long-lasting catalyst for syngas generation can be obtained.
(2) The catalyst for syngas generation of (1) can be obtained with good productivity and at low cost.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of a synthesis gas generating catalyst according to the present invention.
FIG. 2 is an enlarged view of a main part A of FIG.
FIG. 3 is an enlarged view of a main part B of FIG. 2;
FIG. 4 is a diagram showing a relationship between a reaction temperature and a methane conversion in Examples.
FIG. 5 is a partial cross-sectional view of a conventional synthesis gas generating catalyst.
FIG. 6 is an enlarged view of a main part C of FIG.
FIG. 7 is an enlarged view of a main part D of FIG. 6;
[Explanation of symbols]
11 Honeycomb type substrate 12 Active metal 31 Raw material powder 32 Mesopore 33 Macropore

Claims (9)

A catalyst for reforming natural gas containing methane as a main component to produce a synthesis gas composed of hydrogen and carbon monoxide. A catalyst for syngas generation, wherein an active metal is supported inside a material wall. In a catalyst for reforming natural gas containing methane as a main component and generating a synthesis gas composed of hydrogen and carbon monoxide, the mixture is extruded into a honeycomb shape using a kneaded mixture of raw material powder and an organic binder. A catalyst for syngas generation, wherein an active metal is supported on a surface portion of a base material wall of a honeycomb base material obtained by firing an extruded body and inside the base material wall. 3. The honeycomb substrate according to claim 1, wherein the honeycomb substrate has a porous shape, and has mesopores between the raw material powders and macropores due to degassing of the organic binder during firing. 4. The catalyst for producing synthesis gas as described in the above. The synthesis gas generating catalyst according to any one of claims 1 to 3, wherein the active metal is supported on the surfaces of the raw material powder facing the macropores and the raw material powder near the raw material powder. The catalyst for syngas generation according to any one of claims 1 to 4, wherein the amount of the active metal carried per liter of bulk volume of the honeycomb substrate is 0.1 to 4 g / l. The synthesis gas generation according to any one of claims 1 to 5, wherein a main component of the honeycomb substrate is a simple substance of alumina, cerium oxide, or zirconium oxide, or a composite oxide obtained by combining two or more of them. Catalyst. In a method for producing a catalyst for reforming a natural gas containing methane as a main component and generating a synthesis gas composed of hydrogen and carbon monoxide, an organic binder is mixed and kneaded with a raw material powder, and the kneaded material is subjected to kneading. After extrusion molding into a honeycomb shape by using, the extruded body is subjected to a baking treatment to obtain a honeycomb-type substrate, and the honeycomb-type substrate is immersed in an aqueous solution containing active metal ions, and then subjected to a baking treatment again. A method for producing a synthesis gas generating catalyst, comprising: supporting an active metal on a surface portion of a substrate wall of a honeycomb-type substrate and inside the substrate wall. The method for producing a catalyst for syngas generation according to claim 7, wherein an organic binder such as methylcellulose is mixed with the raw material powder, which is a mixture of alumina powder and cerium nitrate. 8. A synthesis gas generating method according to claim 7, wherein an organic binder such as methylcellulose is mixed with the raw material powder comprising alumina powder, cerium nitrate, or zirconium nitrate alone or a mixture of two or more of them. Method for producing catalyst.

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