Metal particle-dispersed composite oxides, metal particle-dispersed composite oxide-sintered bodies, method of manufacturing metal particle-dispersed composite oxides, and hydrocarbon-based fuel reformer

• US 20040168367A1
• Filed: 02/26/2004
• Published: 09/02/2004
• Est. Priority Date: 02/27/2003
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Suetsuna, Tomohiro, Fukasawa, Takayuki, Goto, Yasuhiro, Suenaga, Seiichi, Harada, Koichi
• Granted Patent: US 7,435,274 B2
• Time in Patent Office: Days
• US Class Current: 48/127.9
• CPC Class Codes: B01J 15/005 in the presence of catalytically active bodies, e.g. porous plates
• CPC Class Codes: B01J 2219/00157 by means of a burner
• CPC Class Codes: B01J 23/825 with gallium, indium or thallium
• CPC Class Codes: B01J 23/83 with rare earths or actinides
• CPC Class Codes: B01J 23/84 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
• CPC Class Codes: B01J 35/392 Metal surface area
• CPC Class Codes: B01J 35/393 Metal or metal oxide crystallite size
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: B01J 37/08 Heat treatment B01J37/0009, B01J37/0018 take precedence
• CPC Class Codes: B01J 37/18 with gases containing free hydrogen
• CPC Class Codes: C01B 2203/0233 the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/0805 Methods of heating the process for making hydrogen or synthesis gas
• CPC Class Codes: C01B 2203/1023 Catalysts in the form of a monolith or honeycomb
• CPC Class Codes: C01B 2203/1058 Nickel catalysts
• CPC Class Codes: C01B 2203/1094 Promotors or activators
• CPC Class Codes: C01B 2203/1223 Methanol
• CPC Class Codes: C01B 2203/1276 Mixing of different feed components
• CPC Class Codes: C01B 2203/1288 Evaporation of one or more of the different feed components
• CPC Class Codes: C01B 3/326 characterised by the catalyst
• CPC Class Codes: C01B 3/40 characterised by the catalyst
• CPC Class Codes: H01M 8/0618 : Reforming processes, e.g. autothermal, partial oxidation or steam reforming
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 20/52 : using catalysts, e.g. selective catalysts
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

There is disclosed a metal particle-dispersed composite oxide comprising a matrix material containing a composite oxide comprising a non-reducible metal oxide and an easily reducible metal oxide, the composite oxide containing 0.01 to 0.25 mol % of at least one additive metal selected from Al, Sc, Cr, B, Fe, Ga, In, Lu, Nb and Si, surface metal particles precipitated on an outer surface of the matrix material containing the composite oxide, and inner metal particles precipitated on an inner surface of the matrix material containing the composite oxide.

Claims

1. A metal particle-dispersed composite oxide comprising:

a matrix material containing a composite oxide comprising a non-reducible metal oxide and an easily reducible metal oxide, the composite oxide containing 0.01 to 0.25 mol % of at least one additive metal selected from Al, Sc, Cr, B, Fe, Ga, In, Lu, Nb and Si;

surface metal particles precipitated on an outer surface of the matrix material containing the composite oxide; and

inner metal particles precipitated on an inner surface of the matrix material containing the composite oxide.

2. The metal particle-dispersed composite oxide according to claim 1, wherein a volume fraction of the inner metal particles is 0.01% to 1%.

3. The metal particle-dispersed composite oxide according to claim 1, wherein an average particle diameter of the surface metal particles is 10 nm or more.

13. A hydrocarbon fuel reformer comprising:

a fuel tank accommodating a hydrocarbon fuel;

a reforming agent tank accommodating a reformer for reforming the hydrocarbon fuel;

a preliminary heater vaporizing the hydrocarbon fuel and the reforming agent;

a mixer mixing the vaporized hydrocarbon fuel and the vaporized reforming agent;

a reformer having a catalyst layer containing a reforming catalyst occurring a reaction in a mixed gas obtained from the mixer to reform the mixed gas into a fuel mainly comprising hydrogen gas, the reforming catalyst being formed of metal particles-dispersed composite oxide of claim 1;

and

a heater heating the reformer.

14. The hydrocarbon fuel reformer according to claim 13, wherein a volume fraction of the inner metal particles in the metal particle-dispersed composite oxide is 0.01% to 1%.

15. The hydrocarbon fuel reformer according to claim 13, wherein an average particle diameter of the surface metal particles in the metal particle-dispersed composite oxide is 10 nm or more.

4. A metal particle-dispersed composite oxide-sintered body comprising:

a metal particle-dispersed composite oxide existing in a region of the sintered body extended from the surface thereof to a depth of 10 μ

m, the metal particle-dispersed composite oxide including a matrix material containing a composite oxide comprising a non-reducible metal oxide and an easily reducible metal oxide, the composite oxide containing 0.01 to 0.25 mol % of at least one additive metal selected from Al, Sc, Cr, B, Fe, Ga, In, Lu, Nb and Si;

surface metal particles precipitated on an outer surface of the matrix material containing the composite oxide; and

inner metal particles precipitated on an inner surface of the matrix material containing the composite oxide.

5. The metal particle-dispersed composite oxide-sintered body according to claim 4, wherein a volume fraction of the inner metal particles in the metal particle-dispersed composite oxide is 0.01% to 1%.

6. The metal particle-dispersed composite oxide-sintered body according to claim 4, wherein an average particle diameter of the surface metal particles in the metal particle-dispersed composite oxide is 10 nm or more.

7. A method of manufacturing a metal particle-dispersed composite oxide comprising:

mixing a powder of a non-reducible metal oxide, a powder of an easily reducible metal oxide and a powder containing at least one additive metal selected from Al, Sc, Cr, B, Fe, Ga, In, Lu, Nb and Si to obtain a mixed powder containing the additive metal at a ratio of 0.01 to 0.25 mol %;

molding the mixed powder into a molded body;

sintering the molded body to obtain a sintered body formed of a composite oxide comprising the non-reducible metal oxide and the easily reducible metal oxide; and

subjecting the sintered body to a reducing treatment to precipitate particles of the easily reducible metal oxide on a surface of the composite oxide.

8. The method according to claim 7, wherein the powder of a non-reducible metal oxide includes a carbonate hydroxide compound phase.

9. The method according to claim 7, wherein the powder of a non-reducible metal oxide includes not less than 5% by weight of a carbonate hydroxide compound phase.

10. A method of manufacturing a metal particle-dispersed composite oxide sintered body comprising:

preparing a couple of green sheets each containing a powder of a non-reducible metal oxide, a powder of an easily reducible metal oxide and an organic binder;

preparing a carbon slurry containing carbon, an easily reducible metal oxide and a binder;

coating the carbon slurry on one major surface of one of the green sheets to form a carbon slurry layer having a pattern of channel;

laminating the other one of the green sheets on the one of green sheets having the carbon slurry layer formed thereon and pressing these green sheets together to obtain an integrated green body;

eliminating the binder from the green body;

burning the carbon included in the carbon slurry layer to obtain a channel pattern;

sintering the green body having the channel pattern to obtain a sintered body; and

subjecting the sintered body to heat treatment in a reducing gas atmosphere to reduce the easily reducible metal oxide to precipitate metal particles in a form of the channel pattern.

11. A method of manufacturing a metal particle-dispersed composite oxide sintered body comprising:

preparing three green sheets each containing a non-reducible metal oxide, an easily reducible metal oxide and an organic binder;

forming a pattern of channel in one of the green sheet by punching;

interposing the green sheet having the channel pattern formed therein between the remaining couple of the green sheets and pressing these green sheets together to obtain an integrated green body;

cutting the integrated green body into a predetermined size to expose ends of the channel pattern;

eliminating the binder from the green body;

sintering the green body eliminated of the binder to obtain a sintered body; and

subjecting the sintered body to heat treatment in a reducing gas atmosphere to reduce the easily reducible metal oxide to precipitate metal particles in a form of the channel pattern.

12. A method of manufacturing a metal particle-dispersed composite oxide sintered body comprising:

preparing a couple of sheets each formed of a non-reducible metal oxide and having a first major surface and a second major surface;

forming a fluid passage groove on the first major surface of each of the sheets;

forming a layer of an easily reducible metal on a surface of the fluid passage groove;

laminating the couple of sheets each other with the first major surfaces of these sheets being contacted with each other to obtain a laminate;

subjecting the laminate to heat treatment to occur diffusion solid solution between the non-reducible metal oxide and the easily reducible metal to form a diffusion solid solution layer; and

subjecting the heat-treated laminate to heat treatment in a reducing gas atmosphere to reduce the easily reducible metal included in the diffusion solid solution layer to precipitate particles of the easily reducible metal in the fluid passage groove.