Diesel particulate filter and exhaust emission control system

• US 7,923,408 B2
• Filed: 02/20/2007
• Issued: 04/12/2011
• Est. Priority Date: 02/21/2006
• Status: Expired due to Fees

• Current Assignee: Dowa Electronics Materials Co. Ltd. (DOWA Holdings Company Limited)
• Original Assignee: Dowa Electronics Materials Co. Ltd. (DOWA Holdings Company Limited), Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Inventors: Yano, Takuya, Takahashi, Masashi, Tanada, Hiroshi
• Primary Examiner(s): Nguyen; Cam N
• Application Number:
  US11/707,893
• Publication Number:
  US 20070196246A1
• Time in Patent Office: 1,512 Days
• Field of Search: 502/302, 502/303, 502/304, 502/324, 502/327, 502/328, 502/332, 502/333, 502/334, 502/336, 502/338, 502/339, 502/340, 502/341, 502/349, 502/350, 502/351, 502/355, 502/439, 422/177
• US Class Current: 502/327
• CPC Class Codes: B01D 2255/2042 Barium
• CPC Class Codes: B01D 2255/2073 Manganese
• CPC Class Codes: B01D 2255/20738 Iron
• CPC Class Codes: B01D 2255/402 Perovskites
• CPC Class Codes: B01D 2258/012 Diesel engines and lean burn gasoline engines
• CPC Class Codes: B01D 53/944 Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts three-way-catalysts [TWC] B01D53/9445
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/8892 Manganese
• CPC Class Codes: B01J 23/8986 with manganese, technetium or rhenium
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/25 Barium
• CPC Class Codes: B01J 2523/3706 Lanthanum
• CPC Class Codes: B01J 2523/72 Manganese
• CPC Class Codes: B01J 2523/842 Iron
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: C01G 45/1264 containing rare earth, e.g. La1-xCaxMnO3, LaMnO3
• CPC Class Codes: C01G 49/009 Compounds containing, besides iron, two or more other elements, with the exception of oxygen or hydrogen
• CPC Class Codes: C01P 2002/34 perovskite-type (ABO3)
• CPC Class Codes: C01P 2002/77 by unit-cell parameters, atom positions or structure diagrams
• CPC Class Codes: C01P 2006/12 : Surface area
• CPC Class Codes: C01P 2006/16 : Pore diameter
• CPC Class Codes: C04B 2235/3215 : Barium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3227 : Lanthanum oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/443 : Nitrates or nitrites
• CPC Class Codes: C04B 2235/5409 : expressed by specific surface values
• CPC Class Codes: C04B 2235/5436 : micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/6562 : Heating rate
• CPC Class Codes: C04B 2235/768 : Perovskite structure ABO3
• CPC Class Codes: C04B 35/016 : based on manganites
• CPC Class Codes: C04B 35/2641 : Compositions containing one or more ferrites of the group comprising rare earth metals and one or more ferrites of the group comprising alkali metals, alkaline earth metals or lead
• CPC Class Codes: C04B 35/6261 : Milling
• CPC Class Codes: F01N 13/0097 : the purifying devices are arranged in a single housing
• CPC Class Codes: F01N 2330/06 : Ceramic, e.g. monoliths
• CPC Class Codes: F01N 3/0222 : the structure being monolithic, e.g. honeycombs
• CPC Class Codes: F01N 3/0253 : adding fuel to exhaust gases
• CPC Class Codes: F01N 3/035 : with catalytic reactors , e.g. catalysed diesel particulate filters
• CPC Class Codes: F02B 37/00 : Engines characterised by provision of pumps driven at least for part of the time by exhaust
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

Diesel particulate filter that can lower the particulate matter (PM) combustion start temperature and use material containing silicon (Si) for a carrier. The carrier, which has a filter function, is allowed to support a perovskite-type complex oxide expressed by formula (1) as follows, wherein 0<x<0.7 and 0≦y≦1: formula (1)=La_1-xBa_xMn_yFe_1-yO₃.

Claims

1. A diesel particulate filter, comprising:

a carrier which has filter functions, wherein fine pores are formed in said carrier; and

a perovskite type complex oxide in particulate form supported by said carrier and expressed by the following formula (1);

La_1-xBa_xMn_yFe_1-yO₃  

 

(1)

in which 0<

x<

0.7 and 0≦

y≦

1,

wherein the particle diameter of the perovskite type complex oxide is smaller than the fine pore diameter of said carrier.

2. The diesel particulate filter according to claim 1 wherein 0.1≦

x≦

0.6 in formula (1) above.

3. The diesel particulate filter according to claim 1 wherein y=0 in formula (1) above.

4. The diesel particulate filter according to claim 1 wherein y=1 in formula (1) above.

5. The diesel particulate filter according to claim 1

further comprising an oxidation catalyst containing at least one element selected from the group consisting of Pt, Rh, and Pd, which is supported by a carrier.

6. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises a carrier which has filter functions and a perovskite type complex oxide supported by said carrier and expressed by the following formula (1); and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter;

La_1-xBa_xMn_yFe_1-yO₃ (1)

(where 0<

x<

0.7 and 0≦

y≦

1 in formula (1) above).

7. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises a carrier which has filter functions and a perovskite type complex oxide supported by said carrier and expressed by the following formula (1); and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter;

La_1-xBa_xMn_yFe_1-yO₃ 

 

(1)

(where 0.1≦

x≦

0.6 and 0≦

y≦

1 in formula (1) above).

8. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises a carrier which has filter functions and a perovskite type complex oxide supported by said carrier and expressed by the following formula (1); and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter;

La_l-xBa_xMn_yFe_1-yO₃ 

 

(1)

(where 0<

x<

0.7 and y=0 in formula (1) above).

9. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises a carrier which has filter functions and a perovskite type complex oxide supported by said carrier and expressed by the following formula (1); and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter;

La_1-xBa_xMn_yFe_1-yO₃ 

 

(1)

(where 0<

x<

0.7 and y=1 in formula (1) above).

10. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises a carrier which has filter functions and a perovskite type complex oxide supported by said carrier and expressed by the following formula (1), wherein the perovskite type complex oxide exists in a particulate form, fine pores are formed in the carrier, and the particle diameter of the perovskite type complex oxide is smaller than the fine pore diameter of the carrier; and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter;

La_1-xBa_xMn_yFe_1-yO₃ 

 

(1)

(where 0<

x<

0.7 0≦

y≦

1 and in formula (1) above).

11. An exhaust emission control system installed in an exhaust gas passage of a diesel engine, comprising:

a diesel particulate filter that comprises

a carrier which has filter functions,

a perovskite type complex oxide supported by said carrier and expressed by the following formula (1)

La_1-xBa_xMn_yFe_1-yO₃ 

 

(1)

in which 0<

x<

0.7 0≦

y≦

1, and

an oxidation catalyst containing at least one element selected from the group consisting of Pt, Rh, and Pd, which is supported by said carrier; and

a carrier which supports an oxidation catalyst installed separately from the diesel particulate filter.