WO2003099434A1

WO2003099434A1 - Catalyst for water gas shift reaction

Info

Publication number: WO2003099434A1
Application number: PCT/JP2003/002618
Authority: WO
Inventors: Atsushi Ueda; Yusuke Yamada; Tetsuhiko Kobayashi
Original assignee: National Institute Of Advanced Industrial Science And Technology
Priority date: 2002-05-01
Filing date: 2003-03-06
Publication date: 2003-12-04
Also published as: AU2003211726A1

Abstract

A catalyst for water gas shift reaction comprising gold and copper oxides, or a catalyst for water gas shift reaction comprising palladium and manganese oxides. These catalysts, as compared with conventional catalysts, are effective at low temperatures and can advance a water gas shift reaction for a prolonged period of time, so that production of hydrogen and removal of carbon monoxide can be performed efficiently.

Description

Description Water gas shift reaction catalyst Technical field

The present invention relates to a catalyst for a water gas shift reaction for producing hydrogen from carbon monoxide and water, and a method for performing a water gas shift reaction in the presence of the catalyst. The present invention also relates to a fuel cell system including a water gas shift reaction catalyst. Background technology '

Hydrogen is useful as an industrial raw material, fuel, etc., and its production technology is extremely important for effective use of hydrogen. Hydrogen is widely used as an industrial raw material in fields such as ammonia production processes, crude oil refining processes, and methanol production processes.As fuels, various heat sources by combustion of hydrogen, internal combustion engines (hydrogen engines), It is used in fuel cell power generation (large-scale power sources, distributed power sources, fuel cell vehicles, etc.).

At present, hydrogen is produced by the reaction of fossil fuels (hydrocarbon raw materials) such as natural gas, petroleum, and coal with steam (steam reforming reaction) and the subsequent hydrogas shift reaction, as outlined in Equation 1. It is manufactured industrially. The gas produced by the steam reforming reaction is called reformed gas and contains hydrogen, carbon dioxide, carbon monoxide, 7j <steam, unreacted hydrocarbons, and the like.

Reference formula 1

Natural gas / oil / coal + steam [steam reforming reaction] → reformed gas – [water gas shift reaction] → hydrogen

A method for producing hydrogen by further reacting carbon monoxide and water vapor contained in the reformed gas (a gas containing carbon monoxide and water vapor is referred to as “water gas”) is known as a water gas shift reaction. Since extremely useful hydrogen can be produced using carbon monoxide, which has few uses, this is an extremely important chemical process in industry.

The reaction between carbon monoxide and water (water vapor) (water gas shift reaction) CO + H ₂ O → H ₂ + CO ₂

It is shown by the reaction formula.

At present, in order to carry out the water gas shift reaction efficiently, a new catalyst capable of promptly proceeding the reaction even under relatively low temperature conditions is required. The main reasons for the need for a new ^ catalyst to efficiently perform the water gas shift reaction (hereinafter sometimes simply referred to as the "shift reaction") even at low temperatures are described below.

(1) In some cases, it is required to start the supply of hydrogen in a very short time and stop it in a very short time.

A specific example of such a reaction is a reaction in a hydrogen supply device for a fuel cell that is assumed to be mounted on an automobile.

In order to achieve the same convenience as a current gasoline engine or diesel engine vehicle, the engine must be started and stopped within a short time of about 10 seconds or less. Therefore, in fuel cell vehicles and fuel cells powered by hydrocarbons such as natural gas, gasoline, and light oil, and methanol-reformed fuel cell vehicles, the rapid hydrogen that can start and stop the shift reaction instantaneously Manufacturing equipment is required.

If the shift reaction can proceed at a low temperature (for example, from around room temperature to about 150 ° C), the required reaction temperature within a short period of time, for example, by electric heating (electric heating by a heating wire) or heating by fuel combustion , And the shift reaction starts rapidly. In this case, rapid start and stop of the engine can be realized in the above-described fuel cell vehicle as in the case of the gasoline vehicle.

(2) Devices that require hydrogen may be used at low temperatures near room temperature.

Specific examples of such applications include power supplies for portable personal computers and power supplies for mobile phones (mobile power supplies).

Today's portable electronic devices, such as portable personal computers and mobile phones, have extremely high-speed information processing capabilities, and their convenience has been significantly improved. This is mainly due to the evolution of hardware such as various electronic devices (CPU processor, hard disk unit, etc.). However, faster processing power necessarily leads to higher power consumption. On the other hand, the technological development of various batteries is relatively behind the development of electronic devices. For example, in the latest portable personal computers and mobile phones, the processing speed and communication speed have been dramatically improved, but the working time has been shortened, and overall convenience has declined. Is seen.

Use of polymer electrolyte fuel cells has attracted attention as one of the means for solving such problems related to mobile power sources. The polymer electrolyte fuel cell uses, for example, methanol directly as fuel, or converts hydrogen obtained by a water gas shift reaction or a methanol reforming reaction into electric power by a fuel cell and uses it. It is very important that this type of power generator (battery) operates from room temperature to about 80 ° C.

It is also conceivable to use heat generated from a CPU processor or the like as a heat source required for the water gas shift reaction. In this case, both cooling of the CPU processor and effective use of heat energy (energy saving) can be achieved.

In the above-mentioned water gas shift reaction, if a sufficient reaction rate can be obtained at about 80 ° C or less, more preferably near room temperature, application to portable electronic devices in the form of a new fuel cell can be greatly expected.

(3) It is necessary to increase the production efficiency of hydrogen at low temperatures.

First, focusing on chemical equilibrium, the water gas shift reaction

Order _{reaction: CO + H 2 0 → H} 2 + C0 2

Reverse reaction: CO + H ₂ 0 — H ₂ + C0 ₂

There is an equilibrium between the forward reaction (water gas shift reaction) and the reverse reaction (reverse water gas shift reaction), as shown by the reaction formula:

This equilibrium favors the forward reaction at lower temperatures (the lower the temperature, the higher the hydrogen concentration at equilibrium). That is, the lower the temperature at which the water gas shift reaction is carried out, the higher the efficiency of hydrogen production.

Furthermore, focusing on the reaction temperature, in general, the higher the temperature of a chemical reaction, the faster the reaction rate. Therefore, in order to increase the efficiency of hydrogen production, in principle, the water gas shift reaction described above must be performed at a relatively high temperature ( (About 250 to 350 ° C.). However, at high temperatures, reactions (side reactions) other than the intended reaction (in this case, the water gas shift reaction) are also promoted, and as a result, the reaction at a high temperature may reduce the hydrogen production efficiency. This side reaction is

CO + 3H ₂ → CH ₄ + H ₂ O

C0 ₂ + 4H ₂ → CH ₄ + 2H ₂ 0

It is a methanation reaction represented by the following reaction formula.

This methanation reaction is a major problem in that it consumes the target product, hydrogen, and reduces the efficiency of hydrogen production. In other words, if the aqueous shift reaction can proceed at a desired high reaction rate even at a low temperature, a heat source for performing the reaction at a high temperature becomes unnecessary, and consumption of hydrogen generated by the methanation reaction can be avoided. However, the production efficiency of hydrogen can be significantly increased.

For the above reasons, there is a strong demand for the development of a new highly active catalyst that can realize a water gas shift reaction at low temperatures.

Conventionally, the following catalysts have been reported as catalysts exhibiting catalytic activity in the water gas shift reaction, but all have low hydrogen production efficiency.

1. Chromium oxide catalyst supporting copper

2. Iron oxide catalyst supporting copper.

3. Copper supported zinc oxide catalyst

4. Cerium oxide catalyst supporting platinum

5. Palladium-supported cerium oxide catalyst

6. Gold supported manganese oxide catalyst

7. Titanium oxide catalyst supporting gold Disclosure of the invention

The present inventor has found that when a specific noble metal is supported on a specific metal oxide, a novel catalyst capable of promoting a water gas shift reaction with high efficiency under low temperature conditions can be obtained.

The inventor has also found that the novel catalyst can exert catalytic activity with high efficiency over a long period of time. _j

Five

That is, the present invention relates to the following items 1 to 30.

Item 1. A water gas shift reaction catalyst containing gold and copper oxide.

Item 2. (1) Gold, (2) Copper oxide (3) At least one selected from the group consisting of magnesium, aluminum, manganese, iron, cobalt, nickel, zinc, zirconium and cerium A water gas shift reaction catalyst comprising an oxide of a metal. Item 3. A catalyst for a water gas shift reaction, wherein the catalyst according to Item 1 or 2 is supported on a carrier.

Item 4. The carrier is a metal oxide carrier selected from the group consisting of alumina, silica, alumina-silica, cordierite, zirconia, cerium oxide, zeolite and titanium oxide, and stainless steel, iron, copper and aluminum. Item 4. The water gas shift reaction catalyst according to the above item 3, wherein the catalyst is at least one metal support selected from the group consisting of:

Item 5. The water gas shift reaction catalyst according to any one of Items 1 to 4, wherein the content of gold is 0.05 to 30% by weight based on the total weight of the catalyst.

Item 6. The water gas shift reaction catalyst according to Item 5, wherein the gold content is 0.1 to 0% by weight based on the total weight of the catalyst.

Item 7. The water gas shift reaction catalyst according to Item 6, wherein the gold content is 0.1 to 3% by weight based on the total weight of the catalyst.

Item 8. A method for performing a water gas shift reaction in the presence of the catalyst according to any one of Items 1 to 7 above.

Item 9. A method for producing hydrogen by performing a water gas shift reaction in the presence of the catalyst according to any one of Items 1 to 7 above.

Item 10. A method for removing carbon monoxide by performing a water gas shift reaction in the presence of the catalyst according to any one of Items 1 to 7 above.

Item 11. (1) A catalyst reaction section containing the catalyst according to any of the above items 1 to 7, and (2) a water gas shift reaction including a supply section for supplying carbon monoxide and water to the catalyst reaction section. Item 12. The method according to Item 11 above, wherein hydrogen is produced by a water gas shift reaction. Item 13. A catalyst reaction section containing the catalyst according to any one of Items 1 to 7 above, wherein the catalyst reaction section includes the catalyst according to any one of Items 1 to 7 for removing carbon monoxide by a water gas shift reaction. ) A fuel cell system including a fuel cell and a mechanism for supplying a hydrogen-containing gas having a reduced carbon monoxide level from the catalytic reaction section to the fuel cell.

Item 15. (1) A fuel cell, (2) a catalyst reaction section containing the catalyst according to any of Items 1 to 7 above, and (3) a carbon monoxide-containing gas from the fuel cell to the catalyst reaction section. A fuel cell system comprising: a supply unit for supplying a gas containing carbon monoxide; and a mechanism for recycling a hydrogen-containing gas having a reduced carbon dioxide level from the catalyst reaction unit to the fuel cell. Item 16. A water gas shift reaction catalyst comprising palladium and manganese oxide. Item 17. (1) Palladium, (2) Oxide of manganese and (3) Oxide of at least one metal selected from the group consisting of iron, cobalt, nickel, copper, zinc, magnesium, zirconium and cerium A catalyst for a water gas shift reaction.

Item 18. A catalyst for a water gas shift reaction, wherein the catalyst according to Item 16 or 17 is supported on a carrier.

Item 19. The carrier is a metal oxide carrier selected from the group consisting of alumina, silica, alumina-silica, cordierite, zirconia, cerium oxide, zeolite and titanium oxide, stainless steel, iron, copper and aluminum. Item 19. The water gas shift reaction catalyst according to Item 18, which is at least one metal-based support selected from the group.

Item 20. The water gas shift reaction catalyst according to any one of Items 16 to 19, wherein the content of palladium is 0.1 to 30% by weight based on the total weight of the catalyst.

Item 21. The water gas shift reaction catalyst according to item 20, wherein the content of palladium is 0.1 to 10% by weight based on the total weight of the catalyst.

Item 22. The water gas shift reaction catalyst according to Item 21, wherein the content of palladium is from 0 :! to 3% by weight based on the total weight of the catalyst.

Item 23. A method for performing a water gas shift reaction in the presence of the catalyst according to any one of Items 16 to 22 above.

Item 2 4. Water gas shift reaction in the presence of the catalyst according to any of Items 16 to 22 above A method of producing hydrogen by performing a reaction.

Item 25. A method for removing carbon monoxide by performing a water gas shift reaction in the presence of the catalyst according to any one of Items 16 to 22 above.

Item 26. (1) For a water gas shift reaction including a catalyst reaction section containing the catalyst according to any of the above items 16 to 22, and (2) a supply section for supplying carbon monoxide and water to the catalyst reaction section Item 27. The apparatus according to the above item 26, wherein the water gas shift reaction removes carbon monoxide according to the above item 26 for producing hydrogen by the water gas shift reaction.

Item 29. (1) a catalyst reaction section including the catalyst according to any of the above items 16 to 22, and (2) a hydrogen-containing gas having a reduced carbon monoxide level from the catalyst reaction section including a fuel cell. A fuel cell system including a mechanism for supplying a fuel cell.

Item 30. (1) A fuel cell, (2) a catalyst reaction section containing the catalyst according to any of the above items 16 to 22, and (3) a supply of supplying carbon monoxide from the fuel cell to the catalyst reaction section A fuel cell system including a unit and a mechanism for recycling a hydrogen-containing gas having a reduced carbon monoxide level from a catalytic reaction unit to a fuel cell. Detailed description of the invention

The present invention provides a water gas shift reaction catalyst obtained by using a combination of a specific noble metal and a specific metal oxide.

As described in detail below, the catalyst according to the present invention can be roughly classified into a gold-copper oxide-based catalyst (referred to as “first catalyst”) and a palladium-manganese oxide-based catalyst (referred to as “second catalyst”). .

(1-1) Gold-copper oxide catalyst

The water gas shift reaction catalyst as the first catalyst of the present invention is a catalyst containing gold and copper oxide as essential components.

The first catalyst of the present invention comprises (1) gold, (2) copper oxide and (3) magnesium, aluminum, manganese, iron, cobalt, nickel, zinc, zirconium and cell oxide. More preferably, the composition has a composition containing at least one metal oxide selected from the group consisting of platinum.

In the first catalyst of the present invention, the metal oxide used in combination with gold (hereinafter referred to as “metal oxide”) includes a mixture of copper oxide and another metal oxide (hereinafter also referred to as “composite oxide”). say.), mixed oxide containing copper, as the AB ₂ 0 ₄ (a having a spinel crystal structure, Cu, Mg, Al, Mn , Fe, Co, Ni, Zn, Zr , etc. are exemplified, and as B is, Cu, Mn Fe, Co, or Ti are exemplified. However, a and a double oxide represented by not the same) and B, Cu as CD0 ₃ (C having a perovskite-type crystal structure, Mn, Fe, etc. are exemplified, and D is Ce, etc.).

As particularly preferred of the present invention the first _{_{_{catalyst, AuZCuAl 2 O 4, AuZCuMn 2}}} 0 4, Au / CuFe 2 O 4, Au / CuZr 2 0 4> Au / Cu'Mg- Oxide, Au / Cu-Co-Oxide > AuZ Cu-Ni-Oxide, AuZCu_Zn-Oxide, Au / Cu-Ce- Oxide, Au / Cu-Fe-Oxide Au ZMg'Cu-Oxide, AuZAl-Cu-Oxide, AuZMn-Cu_Oxide, Au / Co-Cu- Oxide ^ Au / Ni-Cu-Oxide, AuZZirCu-Oxide, AuZZrCu-Oxide, Au / Ce-Cu-Oxide and the like (the description of "Oxide" indicates a composite oxide). The raw material for forming the metal oxide is not particularly limited, and includes nitrates, sulfates, acetates, carbonates, and the like of various metals such as Cu, Mg Al, Mn, Fe Co, Ni, Zn, Zr, and Ce. Various salts such as chlorides (hereinafter referred to as “metal salts”) can be used. The metal oxide is prepared, for example, as follows.

First, a predetermined metal salt is dissolved in water according to the composition of the target catalyst to obtain a first aqueous solution. The concentration of the first aqueous solution can be appropriately selected according to the kind of the metal salt and the like, and is usually about 0.01 to 1 mol ZL, more preferably about 0.05 to 0.3 mol / L.

Separately, at least one selected from the group consisting of hydroxides such as sodium hydroxide and potassium hydroxide, and carbonates such as sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, and ammonium hydrogencarbonate. Dissolve in water to obtain a second aqueous solution. The concentration of the second aqueous solution is not particularly limited, and is usually about 0.01 to 1 mol ZL, more preferably about 0.05 to 0.3 mol ZL. Next, the first aqueous solution and the second aqueous solution are mixed, the resulting precipitate is washed with water, filtered, dried, and calcined to obtain the metal oxide in the first catalyst of the present invention. Can be. ,

The mixing ratio of the first aqueous solution and the second aqueous solution is not limited, but, for example, with respect to 1 volume of the first aqueous solution, about 0.3 to 3 volumes of the second aqueous solution, preferably about 0.5 to 1.5 volumes Use in proportions. At this mixing ratio, a precipitate is efficiently generated, and the loss of the metal salt can be suppressed.

The conditions for washing, filtering, drying, and baking the precipitate are not particularly limited, and can be appropriately selected. For example, drying may be performed at about 30 to 200 ° C., preferably at about 50 to 150 ° C .: for about! To about 15 hours, preferably for about 2 to about 10 hours. The higher the temperature, the shorter the drying time.

The firing conditions may be appropriately selected from the range in which a high-purity oxide is formed.In the atmosphere, the firing temperature is usually about 200 to 600 ° C, preferably about 250 to 550 ° C, and more preferably 250 to 400 ° C. It may be carried out for about 0.5 to 12 hours, preferably for about 1 to 8 hours, more preferably for about 3 to 8 hours. The higher the temperature, the shorter the firing time.

Metal oxides can also be produced by heating the salts of these metals as raw materials, for example, by heating them at about 200 to 600 ° C in the air to remove the salt components and oxidize the metal components. can do.

If necessary, the obtained metal oxide may be further purified according to a known method using a binder such as silica sol, alumina sol, or polyethylene glycol, using honeycomb, peas, pellets, plate, It can be formed into various shapes such as rings.

The molding method can be appropriately selected depending on the desired shape of the catalyst and the like. For example, injection molding, extrusion molding, compression molding, casting into a mold and the like can be mentioned. In the method for producing the first catalyst of the present invention, the gold compound used as a gold component source includes a water-soluble gold compound, a compound soluble in an organic solvent, a sublimable compound, and further, gold chloride, chloroauric acid, And inorganic and organic gold complex compounds.

Examples of water-soluble compounds of gold include gold chloride and chloroauric acid.Examples of compounds soluble in organic solvents include gold acetyl acetonate, and chloro (triphenylphosphine). Gold (I) [AuCl {P (C ₆ H ₅ ) ₃ }] is exemplified, and the sublimable compound is exemplified by gold acetyl acetonate.

The method of immobilizing gold on the metal oxide or its molded body can be performed according to a conventional method. For example, (i) a method of immersing a metal oxide or a molded article thereof in a gold solution (impregnation method), and (ii) mixing the first aqueous solution, the second aqueous solution, and the gold solution, and then adding a gold-metal oxide (Iii) a method of depositing and depositing gold on the surface of a metal oxide or its molded body using a gold solution and various reducing agents, and (iv) using a gold solution. A method of depositing and depositing gold on the surface of a metal oxide or its molded product by light irradiation, and (V) Precipitating and depositing gold on the surface of the metal oxide or its molded product by pH-controlled neutralization of the gold solution (Vi) a method of adsorbing an organic gold complex in a solution on the surface of a metal oxide or a molded body thereof, and (vii) a chemical reaction of an organic gold complex in a gas phase with the surface of the metal oxide or the molded body thereof. (CVD method), (viii) Metal oxide or its molded surface A method of physically vapor-depositing an organic gold complex in the gas phase (PVD); (ix) a method of vacuum-depositing an organic gold complex on the surface of a metal oxide or its molded body; (X) The method can be carried out by a method of injecting gold ions into the surface of the metal oxide or molded article thereof, or (xi) a method of mixing ultrafine gold particles and metal oxide particles. Alternatively, a binder is added to the gold-metal oxide-containing precipitate obtained by the co-precipitation method in the same manner as in the above-mentioned metal oxide molding method, and then, a binder, a bead, a pellet, a plate-like material is formed. It may be formed into a predetermined shape such as a ring shape. The gold immobilized on the metal oxide is preferably in the form of ultrafine particles having a particle size of about lOnm or less, preferably about 2 to 5 mn. A catalyst in which gold particles are immobilized on a metal oxide has a large contact area between the gold and the metal oxide, and can exhibit synergistically excellent catalytic activity.

In the first catalyst of the present invention, the content (amount) of gold is usually about 0.05 to 30% by weight, preferably about 0.1 to 10% by weight, based on the total weight of the metal oxide and gold. , More preferably 0:! ~ 3 weight. /. It is about.

(1-2) A catalyst obtained by supporting the catalyst obtained in (1-1) on a carrier

In the present invention, the fine-particle catalyst obtained in the above step (1-1) is further supported on a metal oxide-based carrier or a metal-based carrier of various shapes to achieve practicality. Can be further improved.

Examples of the metal oxide-based carrier include alumina, silica, alumina-silica, zirconium, cerium oxide, titanium oxide, cordierite, and zeolite. Examples of the metal carrier include stainless steel, iron, copper, and aluminum.

For example, when aluminum is used as a metal-based carrier, the surface of the metal carrier (aluminum) is converted into an oxide, and the structure is made of fine particles of gold Z metal oxide Z oxide of aluminum (alumina) Z aluminum This is preferable since the adhesion to the catalyst is improved.

The metal oxide in the gold-metal oxide catalyst and the metal oxide used as the carrier may be the same or different.

The shape of the support is not particularly limited, and may be any shape generally used as a catalyst support. For example, carriers in the form of powder, sphere, granule, honeycomb, foam, fiber, cloth, plate, ring, etc. can be used. The production of the catalyst with a carrier is not particularly limited, and is carried out by a known method such as a push coat method, a spraying method, a kneading method, and a binder-mixing method, depending on the method of using the carrier, the kind of the target catalyst, and the like. be able to. Among these production methods, the push coat method and the kneading method are more preferable. Hereinafter, a method for supporting a catalyst on a carrier by the wet coat method will be described in detail.

First, the fine particle catalyst produced in the above-mentioned step (1-1) is charged into a Pall mill apparatus, and then pulverized for about 1 to 5 hours. If necessary, a binder (for example, 3 to 20% of the catalyst weight) is used. Of silica sol) and water (for example, about 3 to 30% of the catalyst weight), and knead for about 1 to 5 hours.

After immersing a carrier (for example, a cordierite honeycomb carrier) in the obtained suspension for about 1 to 20 minutes, the carrier is taken out and the excess suspension is removed by blowing compressed air using a spray gun.

Then, the carrier having been subjected to the above treatment is dried at about 50 to 150 ° C. for about 2 to about L0 hours, and then calcined in the air at about 250 to 400 ° C. for about 1 to 8 hours, thereby forming a carrier. A catalyst structure carrying a catalyst can be obtained. (1-3) Production of hydrogen or removal of carbon monoxide

When the above-mentioned catalyst for a water gas shift reaction, which is the first catalyst of the present invention, is used, it exhibits higher activity at a lower temperature than the conventional catalyst, so that the production of hydrogen and the removal of carbon monoxide are reduced. It can be performed efficiently.

In the present invention, examples of the gas for supplying carbon monoxide include, but are not limited to, those generated by reforming hydrocarbons derived from fossil fuels such as petroleum, coal, and natural gas. .

The removal of carbon monoxide and the production of hydrogen by the water gas shift reaction can vary depending on the concentration of carbon monoxide in the water gas, the coexisting components in the water gas, the content of gold in the catalyst, and the like. It is carried out by reacting water (steam) and carbon monoxide at a temperature of about 25 to 400 ° C, preferably about 80 to 200 ° C in the presence of the first catalyst of the invention.

The concentration of carbon monoxide in the water gas is not particularly limited. For example, for the purpose of producing hydrogen, it is usually about 1 to 30% by volume, preferably about 5 to 30% by volume, and more preferably about 10 to 30% by volume. About 25% by volume. If the purpose is to remove carbon monoxide, 10 ppm to 10 volumes. /. Degree, preferably ΙΟρρπ! About 1% by volume, more preferably about 10 ppm to 1000 ppm.

The amount of water (steam) in the reaction system should be at least the minimum necessary amount (equimolar to carbon monoxide) to completely decompose the carbon monoxide and produce the corresponding amount of hydrogen. Usually, about 1 to 5 times (molar ratio) of carbon monoxide, more preferably about 2 to 3 times water vapor may be present. Further, in the reaction system, for example, a gas such as hydrogen, carbon dioxide, or nitrogen may be present.

In the water gas shift reaction, the flow rate of the gas containing carbon monoxide can be appropriately selected according to the concentration of carbon monoxide and the like. For example, usually about 50 mL to 10 LZ per _{gram of} catalyst, preferably about 50 mL to: It is about 1 LZ. As the space velocity, for example, typically, Β, ΟΟΟ βΟΟ, ΟΟΟΙιτ · 1 mm, preferably S ^ OC ^ eO'OOOhr ¹ extent.

When a gas containing water vapor and carbon monoxide is subjected to the water gas shift reaction in the presence of the first catalyst of the present invention, if necessary, an inert gas such as nitrogen, argon, or helium is used. Gas can be used as carrier gas. Further, a small amount of oxygen (for example, about 10% by volume or less based on carbon monoxide) or a small amount of air (for example, 50% by volume or less based on carbon monoxide) coexist in the carrier gas. You may.

Furthermore, the pressure of including gas an acid I匕炭oxygen when performing the water gas shift reaction using the present invention the first catalyst is not particularly limited, for example, l X 10 ² kPa shell 5 MPa about high pressure conditions You can choose from a wide range up to the bottom.

In the water gas shift reaction using the first catalyst of the present invention, by circulating the gas to be reacted, the concentration of carbon monoxide can be further reduced, or the obtained hydrogen concentration can be increased.

The present invention according to the first catalyst comprises: a catalyst reaction section containing the first catalyst of the present invention obtained in (1-1) or (1-2); and supplying carbon monoxide and water to the catalyst reaction section. An apparatus for a water gas shift reaction including a supply section is included. Such an apparatus can be used as a hydrogen production apparatus or as a carbon monoxide removal apparatus.

The present invention according to the first catalyst further comprises: (A) a catalyst reaction section containing the first catalyst of the present invention obtained in (1-1) or (1-2); and (B) a fuel cell, The present invention also includes a fuel cell system provided with a mechanism for supplying a hydrogen-containing gas having a reduced carbon monoxide level to a fuel cell from a reaction section.

Furthermore, the present invention according to the first catalyst comprises (C) a fuel cell, (D) a catalyst reaction section containing the catalyst obtained in (1-1) or (112), and (E) the fuel cell. A hydrogen-containing gas having a reduced carbon monoxide level from the catalyst reaction section to the fuel cell, including a carbon monoxide-containing gas supply section for supplying a carbon monoxide-containing gas to the catalyst reaction section from the fuel cell (recycle) The present invention also includes a fuel cell system provided with a mechanism for performing the above.

These fuel cell systems have the same components as the known fuel cell system except that the first catalyst of the present invention is essential.

The first catalyst of the present invention can be supported on a metal oxide-based, semiconductor-based, or metal-based substrate material of any shape. Therefore, by finely processing the first catalyst of the present invention on a silicon substrate or a silicon oxide (silica) substrate generally used in the semiconductor industry and directly supporting the catalyst, a small-sized electronic device such as a portable personal computer, a PDA, and a mobile phone can be obtained. It can also be used in a form suitable as a hydrogen supply device for a source fuel cell. <Second catalyst>

(2-1) Palladium-manganese oxide catalyst

The second catalyst of the present invention is a water gas shift reaction catalyst containing palladium and manganese oxide as essential components.

The second catalyst of the present invention is more preferably selected from the group consisting of (1) palladium, (2) manganese oxide and (3) cobalt, nickel, copper, zinc, magnesium, zirconium and cerium. The catalyst contains at least one metal oxide.

In the second catalyst of the present invention, the metal oxidized product excluding palladium (hereinafter referred to as “metal oxide”) is a mixture of a manganese oxide and another metal oxidized product (hereinafter, referred to as “metal oxide”). also referred to as "composite oxide".), Fukusani匕物, mixed oxide containing iron containing manganese, as the AB ₂ 0 ₄ (a having a spinel type crystal structure Mn, Fe, Co, Ni, Cu , Zn, Mg or the like. Examples of the B Mn, Fe Co, and the like. However, composite oxide represented by not the same) and a and B, CD0 ₃ having a perovskite-type crystal structure (C is exemplified by Ce and the like, and D is exemplified by Mn, Fe and the like).

As particularly preferred of the present invention the second _{_{catalyst, Pd / FeMn 2 O 4,}} PdZCoMn 2 O 4, Pd, NiMn 2 0 4, Pd, CuMn 2 0 4, Pd / ZnMn 2 0 4, Pd / MgMn 2 0 4 _{_{, Pd / MnCo 2 0 4,}} Pd / MnNi 2 0 4, PdZMnFe 2 0 4, PdZCoFe 2 0 4, Pd / NiPe 2 O 4,

_{_{Pd / ZnFe 2 0 4, Pd}} / MgFe 2 0 4, Pd / FeCo 2 0 4, Pd / ZrMn xide, Pd / Ce- Mn-Oxide, Pd / Zr-Fe-Oxide Pd / Ce'Fe- Oxide, etc. (What is described as “Oxide” indicates a composite oxide.)

The metal oxide raw material for obtaining the metal oxide is not particularly limited, and includes nitrates, sulfates, and acetic acids of various metals such as Mn, Fe, Co, Ni, Cu, Zn, Mg, Τί, La, Sr, and Ce. Various salts such as salts, carbonates and chlorides (hereinafter referred to as “metal salts”) can be used.

First, a metal salt required according to the target catalyst is dissolved in water to obtain a third aqueous solution. The concentration of the third aqueous solution can be appropriately selected according to the type of the metal salt and the like, and is, for example, about 0.01 to 1 mol / L, preferably about 0.05 to 0.3 mol ZL. Next, various hydroxides such as sodium hydroxide and 7_K potassium oxide, and carbonates such as sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonium hydrogen carbonate, etc. Dissolve at least one species in water to obtain a fourth aqueous solution. The concentration of the fourth aqueous solution is not particularly limited, and may be about 0.01 to 1 mol / L, preferably about 0.05 to 0.3 mol ZL.

Next, the third aqueous solution and the fourth aqueous solution are mixed, the resulting precipitate is washed with water, filtered, dried, and calcined, whereby the metal oxide in the second catalyst of the present invention can be obtained. .

The mixing ratio of the third aqueous solution and the fourth aqueous solution is not limited, but about 0.3 to 3 volumes, preferably about 0.5 to 1.5 volumes, of the fourth aqueous solution is used per 1 volume of the third aqueous solution. Is preferred. This is because precipitates can be efficiently generated and the loss of metal salts can be suppressed.

The conditions for washing, filtration, drying, and baking are not particularly limited and can be appropriately selected. For example, the same conditions as those used for obtaining the first catalyst of the present invention may be used.

In addition, it can also be produced by heating salts of these metals, which are metal oxide raw materials, in air at, for example, about 200 to 600 ° C.

The obtained metal oxidized product may be mixed with a known binder such as silica sol, alumina sol, or polyethylene glycol, if necessary, and then molded, dried, and fired to obtain a honeycomb, beads, or the like. It can be formed into various shapes such as pellets, plates and rings.

The molding method can be appropriately selected according to the desired shape of the catalyst and the like, and examples thereof include injection molding, extrusion molding, compression molding, and casting into a mold. In the method for producing the second catalyst of the present invention, the palladium compound used as the source of the palladium component includes a water-soluble compound of palladium, a compound soluble in an organic solvent, a sublimable compound, and further, palladium salt and palladium nitrate. , Palladium acetate and various inorganic and organic palladium complex conjugates.

The water-soluble compound of palladium, palladium nitrate, palladium sulfate, Shioi匕palladium, palladium _{_{_{bromide, H 2 PdCl 4, K 2}}} PdCl 4, K 2 PdBi '4, Pd (NH 3) 4 Cl 2, Pd ( NH ₃ ) ₂ Cl ₂ , Pd (N0 ₂ ) ₂ (NHL) ₂ , Pd (NH ₃ ) ₄ (OH) ₂ , PdCl ₂ (C ₂ H ₈ N ₂ ) Compounds soluble in organic solvents include palladium acetate, palladium (II) acetylacetonate, palladium chloride, Pd (NH ₃ ) ₄ Cl ₂ , Pd (NH ₃ ) ₂ Cl ₂ Pd (N0 ₂ ) ₂ (NH ₃ ) ₂ , Pd (N0 ₃₎ ₂ and the like. examples of palladium ([pi) Asechiruaseto diisocyanate and the like can be exemplified as a sublimable compound.

The method of immobilizing palladium on a metal oxide or its molded body can be performed according to a standard method. For example, in the methods described in (i) to (xi) of the first catalyst of the present invention, gold can be used instead of palladium.

The palladium immobilized on the metal oxidized product is preferably in the form of fine particles having a particle diameter of about 10 nm or less, preferably about 2 to 5 nm. A catalyst in which palladium fine particles are immobilized on a metal oxide film has a large contact area between the palladium and the metal oxide film, and can exhibit synergistically excellent catalytic activity.

In the second catalyst of the present invention, the content (supporting amount) of palladium is about 0 :! to about 30% by weight, preferably about 0.1 to: L0% by weight, based on the total amount of the metal oxide and the palladium. It is more preferably about 0.1 to 3% by weight.

(2-2) A catalyst body in which the catalyst obtained in (2-1) is supported on a carrier

In the second aspect of the present invention, the particulate catalyst obtained in (2-1) is further supported on a metal oxide-based carrier or a metal-based carrier in various shapes to improve the practicality. Can be. The same catalyst as the first catalyst of the present invention can be used as the metal oxide-based carrier and the metal-based carrier.

The metal oxide in the palladium-metal oxide catalyst and the metal oxide used as the carrier may be the same or different.

The shape of the carrier is not particularly limited, and those exemplified for the first catalyst of the present invention can be used. Further, the method for supporting the catalyst on the carrier and the production conditions are not limited, and for example, the method used for the first catalyst of the present invention can be used.

(2-3) Production of hydrogen or removal of carbon monoxide

In the case where the above-mentioned water gas shift reaction catalyst, which is the second catalyst of the present invention, is used, it exhibits higher activity at a lower temperature than the conventional catalyst, so that the production of hydrogen and the removal of carbon monoxide are reduced. It can be performed efficiently.

Various conditions for performing the water gas shift reaction using the second catalyst of the present invention are also limited. Absent. For example, the same conditions as those for performing a water gas shift reaction using the first catalyst of the present invention can be mentioned.

In particular, for example, 0.5 volume of carbon monoxide. /. Degree, hydrogen 2.7 capacity. /. Degree, carbon dioxide

0.3 capacity. /. Degree, steam 1 ~ 1.5 volume. /. 80 ~: 120 ° C, about 1% by volume of carbon monoxide, about 5% by volume of hydrogen, 0.5% of carbon dioxide. /. If the gas contains about 2 to 3% by volume of water vapor, 80 to: LOOt: About 1 to 7 LZ of palladium is passed through at a flow rate of about 1 to 7 LZ. Carbon concentration

This is a very low value of about 20 ppm or less, and can be used as hydrogen for polymer electrolyte fuel cells.

Also in the water gas shift reaction using the second catalyst of the present invention, by circulating the gas to be reacted, the concentration of carbon monoxide can be further reduced, or the obtained hydrogen concentration can be increased.

The second catalyst of the present invention, like the first catalyst of the present invention, can also be used in a water gas shift reaction device, a hydrogen production device, a carbon monoxide removal device, or a fuel cell system. Further, similarly to the first catalyst of the present invention, it can be used in a form suitable as a hydrogen supply device for a fuel cell for a small power source such as a portable personal computer, a portable terminal, and a mobile phone. Example

Examples are shown below to further clarify the features of the present invention. Hereinafter, Examples 11 to 11 are examples relating to the first catalyst of the present invention, and Examples 2-1 to 2-3 are examples relating to the second catalyst of the present invention.

Example 11

* Preparation of catalyst Nos. L-l to l-9

Chloroauric acid [HAuCl ₄ '4H ₂ 0] 0.250 g (0.000606 mol), Copper nitrate [Cu (N0 ₃ ) ₂ ' 3H ₂₀ ] 4.83 g (0.020 mol), Iron nitrate [Fe (N0 ₃ ) ₃ '9H ₂₀ ] 16.2 g (0.040 mol) was dissolved in 600 ml of distilled water to obtain solution A. On the other hand, 9.47 g (0.0893 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 400 ml of distilled water to obtain a solution B.

Solution A was added dropwise to Solution B above, and the mixture was stirred for 1 hour.The obtained precipitate was washed thoroughly with water. Then, by drying and baking in air at 400 ° C. for 5 hours, a gold-immobilized copper-iron oxide in which ultrafine gold particles having a particle diameter of about 2 to 3 nm are immobilized (catalyst No. 1-4) [Au / CuFe ₂ O ₄ > atomic ratio Au: Cu: Fe 2 1:33:66] was obtained.

In addition, the catalysts of the present invention No.l-l to No.l-3 and No.l-5 to No.l-9 were obtained in the same manner as described above using various metal salts.

* Catalyst No.1-10 ~: Preparation of L-18

Manganese nitrate _{_{[Μη (ΝΟ 3) 2 ·}} 6Η 2 0] 11.5g (0.040 mol) and copper nitrate _{_{[Cu (N0 3) 2 -}} 3H 2 0] dissolved 19.3g of (0.080 mol) l, distilled water 000ml The solution C was obtained. On the other hand, 17.8 g (0.168 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 700 ml of distilled water to obtain a solution D.

The solution C was dropped into the solution D, and the mixture was stirred for 1 hour.The resulting precipitate was thoroughly washed and dried, and calcined in air at 400 ° C for 5 hours to obtain manganese copper oxide. [MnCu ₂ Ox] was obtained.

To a 0.001 mol ZL aqueous solution containing 0.0877 g (0.000213 mol) of salted arsenic acid [HAuCl ₄ '4H ₂₀ ], a 0.1 mol ZL aqueous solution of hydroxylating sphere [KOH] was added to adjust the pH to 8. Thereafter, 5 g of the above-mentioned manganese cuprate [MnCu ₂ O _x ] was added, and the mixture was aged for 1 hour.

The obtained mixture was washed with water, dried, and then calcined in air at 400 ° C. for 5 hours to obtain manganese copper oxide immobilized with ultrafine gold particles (catalyst No. 1-12 of the present invention) [AuZ

MnCu ₂ O _x , atomic ratio Au: Mn: Cu = 1: 33: 66] was obtained.

Further, using various metal salts, the catalyst of the present invention No. 1-

10, No.l-ll, No.l-13 to No.l-18 were obtained.

* Hydrogen generation and carbon monoxide removal

Next, 0.15 g of each of the above catalysts (No.l-:! ~ 1-18) sieved to 70 ~: 120 mesh was filled into a glass tube with an inner diameter of 8 nmi, and the temperature was reduced to 50, 80, 120, 150 ° C. At each temperature of, nitrogen gas containing 1% by volume of carbon monoxide and 2% by volume of water vapor was contained in this glass tube.

The water gas shift reaction was carried out at a flow rate of 50 mlZ to measure the hydrogen concentration and the carbon monoxide concentration. Next, based on the following formula, the hydrogen generation rate (%) and the carbon monoxide removal rate (%) were calculated for each catalyst. Hydrogen production rate (%)

Ii {H2 concentration at catalyst layer outlet (%) / Carbon monoxide concentration at catalyst layer inlet (%)} X 100 Removal rate of carbon monoxide (%)

= [1— {Carbon monoxide concentration at catalyst layer outlet (%) / carbon monoxide concentration at catalyst layer inlet (%)}] X 100 The results after 3 hours from the start of the reaction are shown in Table 11-11.

In Table 1-1, for comparison _{_{Cu-ZnO-Al 2 O 3}} ( Comparative Example 1- 1) [Cu = 38 by weight%, Sud 'Chemie Ltd.], Au / Mn0 ₂ (Comparison Example 1-2) The results when Au = 8% by weight and Au / TiO ₂ (Comparative Example 1-3) [Au = 3% by weight] are also shown.

From the results shown in Table 1-1, the use of the catalyst according to the present invention in which ultrafine gold particles were fixed to a metal oxide showed that hydrogen was efficiently converted from water vapor and carbon monoxide at a relatively low temperature. It is clear that it can be manufactured. Furthermore, it is clear that carbon monoxide can be removed efficiently.

Further, the concentration of the generated carbon dioxide was measured with an infrared carbon dioxide meter, and was almost equal to the amount of the consumed carbon. This indicates that carbon monoxide reacted stoichiometrically with water and was converted to carbon dioxide.

(Μ)

z-τ mm

Τ 一! : Halla

0Ζ

819 Mongolian Odf / e :) d 1 ^ 660 / £ 0 OAV Ltd., the GB_ ⁴³⁾ 50g, manganese nitrate _{_{DVtn (N0 3) 2 '6H}} 2 0] 3.63g and copper nitrate _{_{[Cu (N0 3) 2.}} 3H 2 O] 1.53g impregnated with an aqueous solution of, 400 ° It was fired for 5 hours in C, and to obtain an alumina beads carrying CuMn ₂ 0 _4.

Dissolve 0.542 g of salted acid [HAuCl ₄ '4H ₂₀ ] in 300 ml of distilled water and adjust it to ρΗ8 using a 0.5 mol ZL aqueous solution of τΚoxidizing realm [ΚΟΗ] to obtain a solution. Was. Transfer the solution A to Na scan type flask, was added CuMn ₂ 0 ₄ supported alumina beads described above therein. This eggplant type flask was attached to a mouthpiece and aged at 60 ° C. for 1 hour. The resulting catalyst was washed with water, dried and calcined 2 hours at 400 ° C, ultrafine gold particles immobilized copper-manganese oxide on alumina beads catalyst (AuZCuMn ₂ 0 ₄ Z § Ruminabi Ichizu, containing gold the amount 0.5 wt% to obtain a CuMn ₂ 0 ₄ content 3 wt%). 0.75 g of the above catalyst is filled in a glass tube with an inner diameter of 12 mm, and at each temperature of 80, 120, and 150 ° C, 500 ml of nitrogen gas containing 1% by volume of carbon monoxide and 2% by volume of 7K vapor in this glass tube. The hydrogen gas and carbon monoxide concentrations were measured by performing a water gas shift reaction at a flow rate of 1 min, and the hydrogen production rate (%) and the carbon monoxide removal rate (%) were calculated. . The results obtained 3 hours after the start of the reaction are shown in Table 12 (I), and the results obtained 24 hours after the start of the reaction are shown in Table 12 (II).

Table 11-2 (I)

From the results shown in Tables 1-2 (I) and (Π), as a practical form, even when the metal oxide on which ultrafine gold particles were immobilized was supported on alumina beads, water vapor and carbon monoxide were This shows that hydrogen can be produced efficiently at a relatively low temperature for a long time. Furthermore, it is clear that carbon monoxide can be removed efficiently at relatively low temperatures and over a long period of time. Example 11

Cordierite honeycomb with 400 cells (400 cells / square inch) (15 cells x 15 cells x length 2cm, weight 5g), copper naphthenate (5% Naphtex copper (registered trademark), Nippon Chemical Industry Co., Ltd.) Dip coating of a mixed solution (mixed so that the atomic ratio becomes CnZFe = l / 2) with iron naphthenate (5% Naphtex iron (registered trademark), manufactured by Nippon Chemical Industry Co., Ltd.) and dried. after, and calcined 5 hours at 400 ° C, to obtain a co-one diethyl write honeycomb carrying CuFe ₂ 0 _4. CuFe ₂ 0 ₄ support amount (CuFe ₂ O ₄ calculated by the weight change of the honeycomb that put around the carrier) was 3 wt%.

On the other hand, 0.0314 g of salted gold acid [HAuCl ₄ '4H ₂ O] was dissolved in 50 ml of distilled water, and the pH was adjusted to 8 with an aqueous solution of 0.5 mol ZL of a hydroxide hydroxide [KOH]. Obtained. A liquid above CuFe ₂ 0 ₄ supported a cordierite Ha and second cam immersed in this, and kept for 1 hour at 60 ° C.

The obtained catalyst is washed with water, and then calcined at 400 ° C. for 5 hours to obtain a gold-immobilized copper-iron oxide-carrying copper oxide having fine-particle gold having a particle diameter of about 2 to 3 nm immobilized thereon. A honeycomb catalyst (AuZCuFe ₂ O ₄ Z cordierite honeycomb, gold content 0.3% by weight, CuFe ₂ O ₄ content 3% by weight) was obtained.

A part of the above catalyst was cut out (5 cells x 5 cells x 1 cm in length), filled into a glass tube with an inner diameter of 12 mm, and 1 volume of carbon monoxide was added to this glass tube at 80, 120, and 150 ° C. Gas at a flow rate of 140 mlZ (equivalent to a space velocity of 20,000 / hr) while measuring the concentration of hydrogen and carbon monoxide in the gas at the outlet of the glass tube, and then shifting the water gas flow. The catalytic performance for the reaction was determined. The results 3 hours after the start of the reaction are shown in Table 13 (I), and the results 24 hours after the start of the reaction are shown in Table 1-3 (II).

Table 1-3 (I)

Temperature (° C) 80 120 150 Hydrogen generation rate (%) 15.4 28.4 42.1 Carbon monoxide removal rate (%) 16.1 28.9 43.7 Table 1-3 (II)

From the above results, as a practical form, a catalyst for hydrogen production using steam and carbon monoxide as raw materials even when a metal oxide having immobilized ultrafine gold particles is supported on a cordierite honeycomb. As a result, or as a catalyst for removing carbon monoxide, it can be seen that the catalyst exhibits practically sufficient activity.

Example 2-1

* Preparation of catalyst No. 2-l, 2-4 to 2-6

0.140 g (0.000606 mol) of palladium nitrate [Pd (NO ₃ ) ₂ ], 11.5 g (0.040 mol) of manganese nitrate [Μη (Ν0 ₃ ) ₂ · 6H ₂ 0], and iron nitrate [Fe (N0 ₃ ) ₃ · 9H ₂₀ ] 8.08 g (0.020 mol) was dissolved in 600 ml of distilled water to obtain solution A. On the other hand, 8.98 g (0.0847 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 400 ml of distilled water to obtain a solution B.

After the solution A is dropped into the solution B and stirred for 1 hour, the obtained precipitate is sufficiently washed with water, dried, and calcined in air at 400 ° C. for 5 hours to obtain hydrogen (2% by volume). By carrying out a reduction treatment at 400 ° C for 2 hours while flowing nitrogen gas containing palladium, palladium-immobilized iron manganese oxide in which ultrafine palladium having a particle size of about 2 to 5 mn is immobilized (the present invention) catalyst _{_{No. 2-1) [PdZFeMn 2 0 4}} , an atomic ratio Pd: Fe: Mn = l: 33: 66] to obtain a 'Further, by the same method as above, using various metal salts, the present invention 2 Catalyst Nos. 2-4 to 2-6 were obtained.

* Preparation of catalyst No.2-2, 2-7 ~ 2_9

Dissolve 23.0 g (0.080 mol) of manganese nitrate [Μη (Ν0 ₃ ) ₂ · 6Η ₂₀ ] and 11.6 g (0.040 mol) of cobalt nitrate [Co (N0 ₃ ) ₃ -6H ₂ O] in 1,000 ml of distilled water The solution C was obtained. On the other hand, 15.3 g (0.144 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 700 ml of distilled water to obtain a solution D.

After the solution C was dropped into the solution D and stirred for 1 hour, the obtained precipitate was thoroughly washed with water, dried, and calcined in air at 400 ° C for 5 hours to obtain cobalt manganese oxide. Danimono [CoMn ₂ Oj was obtained. 0.0500 g (0.000217 mol) of palladium nitrate [Pd (NO ₃ ) ₂ ] was dissolved in 100 ml of distilled water to obtain a solution E. Solution E was transferred to an eggplant-shaped flask container, and 5 g of the above-mentioned cobalt manganese oxide [CoMn ₂ O ₄ ] was added thereto. This eggplant-shaped flask was attached to a rotary evaporator overnight, and dried under reduced pressure at 60 ° C. to remove water to obtain a mixture.

This mixture is calcined in air at 400 ° C for 5 hours, and subjected to a reduction treatment at 400 ° C for 2 hours while flowing a nitrogen gas containing hydrogen (2% by volume) to oxidize palladium-fixed cobalt manganese. objects (invention catalyst _{No. 2-2) [Pd / CoMn 2} 0 4, the atomic ratio Pd: Co: Mn = l: 33: 66] was obtained.

Further, catalysts of the present invention Nos. 2-7 to 2-9 were obtained using various metal salts in the same manner as described above.

氺 Preparation of catalyst Nos. 2-3 and 2-10

Dissolved manganese nitrate _{_{[Mn (NO 3) 2 '}} 6H 2 0] 23.0g (0.080 mol) and nickel nitrate _{_{[Ni (N0 3) 2 -6H}} 2 O] 11.6g of (0.040 mol) of distilled water 1,000ml To obtain solution F. On the other hand, 15.3 g (0.144 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 700 ml of distilled water to obtain a solution G.

After the solution F was dropped into the solution G and stirred for 1 hour, the obtained precipitate was sufficiently washed with water, dried, and calcined in air at 400 ° C for 5 hours to obtain a nickel manganese oxide. [NiMn ₂ O was obtained.

To a 0.001 mol ethanol mixed solution containing 0.0487 g (0.000217 mol) of palladium acetate [Pd (CCOO) ₂ ] (water: ethanol volume ratio = 1: 1), add a 0.1 mol aqueous solution of hydroxylating water [KOH]. In addition, the pH was adjusted to 8. To this solution, 5 _g of the above-mentioned nickel manganese oxide [NiMn ₂ O ₄ ] was added and kept for 1 hour.

The obtained mixture is washed with water, dried, and calcined in air at 400 ° C for 5 hours, and subjected to a reduction treatment at 400 ° C for 2 hours while flowing nitrogen gas containing hydrogen (2% by volume). As a result, a palladium-immobilized nickel manganese oxide (catalyst No. 2-3 of the present invention) [Pd ZNiMn ₂ O ₄ , atomic ratio Pd: Ni: Mn = 1: 33: 66] was obtained.

In addition, in the same manner as described above, various catalysts (manganese nitrate, nickel nitrate, and palladium acetate) were used to obtain Catalyst No. 2-10 of the present invention. * Preparation of Catalyst No. 2-ll, 2-14 to 2-16

0.140 g (0.000606 mol) of palladium nitrate [Pd (NO ₃ ) ₂ ], 16.2 g (0.040 mol) of iron nitrate [Fe (N0 ₃ ) ₃ 9H ₂₀ ], and manganese nitrate [Μη (ΝΟ ₃ ) ₂ 6 0] 5.73 g (0.020 mol) was dissolved in 600 ml of distilled water to obtain solution H. On the other hand, 10.3 g (0.0967 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 400 ml of distilled water to obtain a solution I.

After the solution H was dropped into the solution I and stirred for 1 hour, the obtained precipitate was thoroughly washed with water, dried, and calcined in air at 400 ° C for 5 hours to obtain hydrogen (2% by volume). Palladium-immobilized manganese iron oxide with ultra-fine palladium particles having a particle size of about 2 to 5 mn fixed by performing a reduction treatment at 400 ° C for 2 hours while flowing nitrogen gas containing (invention catalyst _{No.2-11) [Pd / MnFe 2 0} 4, an atomic ratio Pd: Mn: Fe = l: 33: 66] c also give, in the same manner as above, using various metal salts Thus, Catalyst Nos. 2-14 to 2-16 of the present invention were obtained.

* Preparation of catalyst Νο.2-12, 2-Γ7 ~ 2 ・ 18

32.4 g (0.080 mol) of iron nitrate [Fe (NO ₃ ) ₃ '9H ₂₀ ] and 11.6 g (0.040 mol) of cobalt nitrate [Co (NO ₃ ) ₃ ' 6H ₂₀ ] are dissolved in 1,000 ml of distilled water. To obtain liquid J. Separately, 22.9 g (0.216 mol) of sodium carbonate [Na ₂ CO ₃ ] was dissolved in 1,000 ml of distilled water to obtain a liquid K.

The solution J was dropped into the solution K and stirred for 1 hour.The resulting precipitate was thoroughly washed with water, dried, and calcined in air at 400 ° C for 5 hours to obtain cobalt iron oxide. [CoFe ₂ Oj was obtained.

Palladium nitrate _{_{[Pd (N0 3) 2]}} 0.0496g of (0.000215 mol) was dissolved in 100ml distilled water to obtain a K solution. Liquid K was transferred to an eggplant-shaped flask container, and the cobalt

5 g was added. This eggplant-shaped flask was attached to a rotary evaporator, dried at 60 ° C. under reduced pressure to remove water, and a mixture was obtained. This mixture is calcined in air at 400 ° C for 5 hours, and subjected to a reduction treatment at 400 ° C for 2 hours while flowing a nitrogen gas containing hydrogen (2% by volume), so that the palladium-immobilized cobalt iron oxide is oxidized. objects (invention catalyst _{No.2-12) [Pd / CoFe 2 0} 4 atomic ratio Pd: Co: Fe = l: 33: 66] was obtained.

In addition, in the same manner as above, using various metal salts, the present catalyst No. 2-17 ~ 2-18 were obtained.

Preparation of water catalyst No.2-13, 2-19

Iron nitrate _{_{[Fe (N0 3) 3 '}} 9¾0] 32.4g (0.080 mol) and nickel nitrate _{_{[Ni (NO 3) 2 -}} 6H 2 O] 11.6g of (0.040 mol) was dissolved in distilled water 1,000ml with L A liquid was obtained. On the other hand, to obtain a M solution carbonate Natoriumu [Na ₂ C0 _3] 20.4g of (0.192 mol) was dissolved in distilled water 900 ml.

After the solution L was dropped into the solution M and stirred for 1 hour, the resulting precipitate was thoroughly washed with water, dried, and calcined in air at 400 ° C for 5 hours to obtain a nickel-iron oxide. [NiFe ₂ O ₄ ] was obtained.

0.0483 g (0.000215 mol) of palladium acetate [Pd (CH ₃ COO) ₂ ] in a 0.001 mol water-ethanol mixture solution (water: ethanol volume ratio = 1: 1) in 0.1 mol aqueous solution of potassium hydroxide [KOH] Was added to adjust the pH to 8. To this solution, 5 g of the above-mentioned nickel iron oxide was added and kept for 1 hour. The obtained mixture is washed with water, dried, and calcined in the air at 400 ° C for 5 hours, and subjected to a reduction treatment at 400 ° C for 2 hours while flowing a nitrogen gas containing hydrogen (2% by volume). by performing, palladium immobilized nickel ferrate product (invention catalyst No.2-13) [PdZNiFe ₂ 0 _4, the atomic ratio Pd: Ni: Fe = l: 33: 66] was obtained.

Also, in the same manner as described above, various catalysts (iron nitrate, cobalt nitrate, and palladium acetate) were used to obtain Catalyst No. 2-19 of the present invention.

* Hydrogen generation and carbon monoxide removal

Subsequently, each of the above catalysts (No. 2-1 to 2-19) was sieved to 70 to: 120 mesh, and 0.15 g was filled in a glass tube with an inner diameter of 8 mm. At this temperature, while flowing a nitrogen gas containing 1% by volume of carbon monoxide and 2% by volume of water vapor in the glass tube at a flow rate of 50 mlZ, the hydrogen concentration and the carbon monoxide concentration were measured. The hydrogen generation rate (%) and the carbon monoxide removal rate (%) were calculated in the same manner as in 1.

The results 3 hours after the start of the reaction are shown in Table 2-1. In Table 2-1, Cu-ZnO_Al ₂ 0 ₃ for comparison (comparative product 1) [Cu = 38 wt%, scan one de 'Chemie Ltd.], PTZ CeO ₂ (Comparative Example 2 2) [Pt = 10% by weight], PdZMnO. (Comparative Example 2-3) [Pd: Mn two 1: 99], 8

27

Pd / Fe ₂ 0 ₃ (Comparative Product 4) [Pd: Fe =] : 99] are also shown the results obtained by using.

Table 2-1

From the results shown in Table 2-1, it is clear that hydrogen can be produced efficiently from water vapor and carbon monoxide at a relatively low temperature by using a catalyst in which ultrafine palladium particles are fixed to metal oxide. is there. It is also clear that carbon monoxide can be removed efficiently.

When the concentration of the generated carbon dioxide was measured by an infrared carbon dioxide meter, it almost coincided with the amount of carbon monoxide consumed. This indicates that carbon monoxide reacted stoichiometrically with water and was converted to carbon dioxide.

Example 2-2

To 50 g of 3 mm diameter T-Alumina beads having a specific surface area of 200 mVg (Mizusawa Chemical Co., Ltd., GB-43), 3.63 g of manganese nitrate [Μη (ΝΟ ₃ ) ₂ · 6Η ₂₀ ] and copper nitrate [Cu (NO ₃ ) _₂ '3H ₂ 0] 1.53g impregnated with an aqueous solution of, and calcined 5 hours at 400 ° C, to obtain an aluminum navigation one's carrying CuMn ₂ 0 _4. Palladium nitrate [Pd (N0 ₃₎ _2] and dissolved in distilled water 300 ml 0.541 g was obtained A solution. Transfer the solution A in an eggplant type flask vessel were added CuM 0 ₄ supported alumina beads described above therein. This eggplant-shaped flask was attached to a rotary evaporator, and dried under reduced pressure at 60 ° (to remove water). The obtained catalyst was calcined at 400 ° C for 5 hours to obtain hydrogen (2% by volume). A reduction treatment is performed at 400 ° C for 2 hours while flowing nitrogen gas containing palladium, whereby a palladium-fixed copper manganese oxide-supported alumina beads catalyst (PdZCuMi ^ OaZ alumina beads, palladium content 0.5 wt. % to obtain a CuMn content of ₂ 0 ₄ 3 wt%).

0.75 g of the above catalyst was filled in a glass tube with an inner diameter of 12 mra. At each temperature of 50, 80, 120, and 150 ° C, 500 ml of nitrogen gas containing 1% by volume of carbon monoxide and 2% by volume of steam The hydrogen gas and carbon monoxide concentrations at the outlet of the glass tube were measured by conducting a water gas shift reaction at a flow rate of, and the hydrogen production rate (%) and the carbon monoxide removal rate () were determined. . The results 3 hours after the start of the reaction are shown in Table 2-2 (I), and the results 24 hours after the start of the reaction are shown in Table 2-2 (II).

Table 2-2 (I)

Temperature O 50 80 120 150 Hydrogen generation rate (%) 34.6 48.8 71.8 89.4 Carbon monoxide removal rate (%) 35.4 49.7 73.6 91.7 Table 2-2 (II)

From the results shown in Tables 2-2 (I) and (Π), as a practical form, even when metal oxide on which ultrafine palladium particles were fixed was supported on alumina beads, water vapor and carbon monoxide were It can be seen that hydrogen can be produced efficiently at a relatively low temperature and for a long time. Furthermore, it is clear that carbon monoxide can be removed efficiently at relatively low temperatures over a long period of time.

Example 2-3

A cordierite honeycomb (5 cells x 5 cells x length lcm) with 400 cells (400 cells Z square inch), iron naphthenate (5% Naphtex iron (registered trademark), Nippon Chemical Industry Co., Ltd.) and nickel Dip coat a mixed solution with naphthenate (5% Naphtex nickel (registered trademark), manufactured by Nippon Kagaku Sangyo Co., Ltd. (mixed so that the atomic ratio is NiZFe = lZ2)), dry and bake at 400 for 5 hours to obtain a cordierite E light honeycomb carrying NiFe ₂ 0 _4.

NiFe ₂ 0 ₄ support amount (calculated by weight change before and after NiFe ₂ 0 ₄ supported) was 2 wt%. Palladium nitrate [Pd (N0 ₃₎ _2] using 0.5 molar aqueous solution of hydroxide force Riumu [KOH] 0.002 molar aqueous solution 100ml was adjusted to pH 8. Adding one of NiFe ₂ 0 ₄ responsible lifting cordierite honeycomb to 2ml of the liquid was aged for 1 hour at 70 ° C.

The obtained catalyst is washed with water, calcined at 400 ° C. for 5 hours, and subjected to a reduction treatment for 2 hours while flowing a nitrogen gas containing hydrogen (2% by volume) to obtain a particle diameter of 2 to 4 nm. Cordierite honeycomb catalyst supporting palladium-immobilized nickel-iron oxide on which palladium in the form of particles is immobilized (PdZNiFe ₂ O ₄ Z cordierite honeycomb, 0.3% by weight of palladium, NiFe ₂ O ₄ 2% by weight). One of the above catalysts was filled in a glass tube with an inner diameter of 12 nm. At each temperature of 50, 80, 120, and 150 ° C, the glass tube contained 140 ml of nitrogen gas containing 1% by volume of carbon monoxide and 2% by volume of steam. By measuring the concentrations of hydrogen and carbon monoxide while circulating at a flow rate per minute (equivalent to a space velocity of 20,000Z hours), the catalytic performance for the water gas shift reaction is measured. I asked. The results 3 hours after the start of the reaction are shown in Table 2-3 (I), and the results 24 hours after the start of the reaction are shown in Table 2-3 (II).

Table 2-3 (I)

From the results shown in Tables 2-3 (I) and (II), as a practical form, even when metal oxide on which palladium fine particles are immobilized is supported on cordierite honeycomb, water vapor and monoacid It can be seen that the catalyst exhibits practically sufficient activity as a catalyst for hydrogen production using arsenic carbon as a raw material, can efficiently produce hydrogen, and can remove carbon monoxide. Industrial applicability

When the catalyst for aqueous shift reaction of the present invention is used, the reaction between carbon monoxide and water (water gas shift reaction) can efficiently proceed even under low temperature conditions. As a result, the production of hydrogen and the removal of Z or carbon monoxide can be performed efficiently. Further, the catalyst for aqueous shift reaction of the present invention can continue to exhibit high activity for a long time.

Claims

The scope of the claims

1. Water-gas shift reaction catalyst containing gold and copper oxide.

2. Oxidation of (1) gold, (2) copper oxide and (3) at least one metal selected from the group consisting of magnesium, aluminum, manganese, iron, cobalt, nickel, zinc, zirconium and cerium. Catalyst for water gas shift reaction,

3. A catalyst for a water gas shift reaction, wherein the catalyst according to claim 1 or 2 is supported on a carrier.

4. The carrier is a metal oxide carrier selected from the group consisting of alumina, silica, alumina-silica, cordierite, zirconium, cerium oxide, zeolite and titanium oxide, and stainless steel, iron, copper and aluminum. 4. The water gas shift reaction catalyst according to claim 3, wherein the catalyst is at least one kind of a metal-based carrier selected from the group consisting of:

5. The content of gold is 0.05 to 30% by weight based on the total weight of the catalyst.

5. The catalyst for a water gas shift reaction according to any one of 4.

6. The water gas shift reaction catalyst according to claim 5, wherein the content of gold is 0.1 to 0% by weight based on the total weight of the catalyst.

7. The water gas shift reaction catalyst according to claim 6, wherein the content of gold is 0.1 to 3% by weight based on the total weight of the catalyst.

8. A method for performing a water gas shift reaction in the presence of the catalyst according to any one of claims 1 to 7.

9. A method for producing hydrogen by performing a 7_ gas shift reaction in the presence of the catalyst according to any one of! To 7.

10. A method for removing carbon monoxide by performing a water gas shift reaction in the presence of the catalyst according to any one of claims 1 to 7.

11. An apparatus for a water gas shift reaction including (1) a catalyst reaction section containing the catalyst according to any one of claims 1 to 7, and (2) a supply section for supplying carbon monoxide and water to the catalyst reaction section. .

12. The method according to claim 11 for producing hydrogen by a water gas shift reaction.

13. The claim for removing carbon monoxide by a water gas shift reaction.

14. (1) Claim: a catalytic reaction section including the catalyst according to any of! To 7, and (2) a hydrogen-containing gas including a fuel cell and having a reduced carbon monoxide level from the catalytic reaction section. Cell system provided with a mechanism for supplying fuel to the fuel cell.

15. (1) A fuel cell, (2) a catalyst reaction section containing the catalyst according to any one of claims 1 to 7, and (3) a carbon monoxide-containing gas is supplied from the fuel cell to the catalyst reaction section. A fuel cell system, comprising: a carbon monoxide-containing gas supply section for recycling a hydrogen-containing gas having a reduced carbon monoxide level from the catalytic reaction section to the fuel cell.

16. Water gas shift reaction catalyst containing palladium and manganese oxide.

17. (1) Oxide of palladium, (2) manganese and (3) oxide of at least one metal selected from the group consisting of iron, cobalt, nickel, copper, zinc, magnesium, zirconium and cerium A catalyst for a water gas shift reaction.

18. A water gas shift reaction catalyst comprising the carrier according to claim 16 or 17 supported on a carrier.

1 9. The carrier is a metal oxide carrier selected from the group consisting of alumina, silica, alumina-silica, cordierite, zirconia, cerium oxide, zeolite and titanium oxide, and a group consisting of stainless steel, iron, copper and aluminum. 19. The water gas shift reaction catalyst according to claim 18, wherein the catalyst is at least one metal support selected from the group consisting of:

20. The water gas shift reaction catalyst according to any one of claims 16 to 19, wherein the content of palladium is 0.1 to 30% by weight based on the total weight of the catalyst.

21. The water gas shift reaction catalyst according to claim 20, wherein the content of palladium is 0.1 to 10% by weight based on the total weight of the catalyst.

22. The water gas shift reaction catalyst according to claim 21, wherein the content of palladium is 0.1 to 3% by weight based on the total weight of the catalyst.

23. A water gas shift reaction in the presence of the catalyst according to any one of claims 16 to 22. How to do.

24. A method for producing hydrogen by performing a water gas shift reaction in the presence of the catalyst according to any one of claims 16 to 22.

25. A method for removing carbon monoxide by performing a water gas shift reaction in the presence of the catalyst according to any one of claims 16 to 22.

26. An apparatus for a water gas shift reaction comprising (1) a catalyst reaction section containing the catalyst according to any one of claims 16 to 22, and (2) a supply section for supplying carbon monoxide and water to the catalyst reaction section. .

27. The apparatus according to claim 26 for producing hydrogen by a water gas shift reaction.

28. The apparatus according to claim 26 for removing carbon monoxide by a water gas shift reaction.

29. (1) a catalyst reaction section containing the catalyst according to any one of claims 16 to 22, and (2) a hydrogen-containing gas containing a fuel cell and having a reduced level of carbon monoxide from the catalyst reaction section. A fuel cell system provided with a mechanism for supplying fuel to a fuel cell.

30. (1) a fuel cell, (2) a catalyst reaction section containing the catalyst according to any one of claims 16 to 22, and (3) a supply of carbon monoxide from the fuel cell to the catalyst reaction section. A fuel cell system including a unit, and a mechanism for recycling a hydrogen-containing gas having a reduced carbon monoxide level from a catalytic reaction unit to a fuel cell.