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US20150285116A1 - Exhaust gas purification catalyst, and exhaust gas purification filter and exhaust gas purification method using the same - Google Patents

Exhaust gas purification catalyst, and exhaust gas purification filter and exhaust gas purification method using the same Download PDF

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Publication number
US20150285116A1
US20150285116A1 US14/674,973 US201514674973A US2015285116A1 US 20150285116 A1 US20150285116 A1 US 20150285116A1 US 201514674973 A US201514674973 A US 201514674973A US 2015285116 A1 US2015285116 A1 US 2015285116A1
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Prior art keywords
exhaust gas
gas purification
support
catalyst
active species
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Inventor
Masashi KIKUGAWA
Kiyoshi Yamazaki
Yuichi Sobue
Seiji Okawara
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Toyota Motor Corp
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Toyota Motor Corp
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Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA reassignment TOYOTA JIDOSHA KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Kikugawa, Masashi, YAMAZAKI, KIYOSHI, SOBUE, YUICHI, OKAWARA, SEIJI
Publication of US20150285116A1 publication Critical patent/US20150285116A1/en
Abandoned legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
    • B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/944—Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
    • B01J27/053—Sulfates
    • B01J27/055—Sulfates with alkali metals, copper, gold or silver
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0236—Drying, e.g. preparing a suspension, adding a soluble salt and drying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/04—Gas or vapour treating; Treating by using liquids vaporisable upon contacting spent catalyst
    • B01J38/12—Treating with free oxygen-containing gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/033—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices
    • F01N3/035—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors, e.g. catalysed diesel particulate filters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/103—Oxidation catalysts for HC and CO only
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/104—Silver
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/209—Other metals
    • B01D2255/2092—Aluminium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/92—Dimensions
    • B01D2255/9202—Linear dimensions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/92—Dimensions
    • B01D2255/9207—Specific surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/01—Engine exhaust gases
    • B01D2258/012—Diesel engines and lean burn gasoline engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/48—Silver or gold
    • B01J23/50—Silver
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/391—Physical properties of the active metal ingredient
    • B01J35/393—Metal or metal oxide crystallite size
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/612—Surface area less than 10 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
    • B01J35/61—Surface area
    • B01J35/615—100-500 m2/g
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
    • F01N2570/04—Sulfur or sulfur oxides

Definitions

  • the present invention relates to an exhaust gas purification catalyst, and an exhaust gas purification filter and an exhaust gas purification method using the same.
  • DPF Diesel Particulate Filter
  • JP 2009-45584 A discloses an exhaust gas purification catalyst for purifying particulate matter in exhaust gas exhausted from an internal combustion engine, and an exhaust gas control apparatus using the same.
  • This exhaust gas purification catalyst includes: a composite oxide (for example, LaMnO 3 , CeZrO 2 , or CoTa 2 O 6 ) having an oxygen releasing capability; and Ag and a noble metal (for example, Ru, Pd, or Pt) co-supported on the composite oxide, in which the composite oxide includes at least two elements selected from the group consisting of an alkali earth metal element, a transition metal element, a Group 12 element, and a Group 13 element.
  • the exhaust gas purification catalyst disclosed in JP 2009-45584 A has a problem in that the activity of the Ag catalyst is significantly decreased due to poisoning by a sulfur component contained in fuel or oil.
  • the activity is extremely high in the initial stage, but a decrease in the activity due to the sulfur component is significant. Therefore, when this highly basic support is exposed to gas containing sulfur, the PM oxidation activity thereof is not sufficient.
  • JP 2011-218295 A discloses an exhaust gas purification filter that is provided in an exhaust gas flow path of an internal combustion engine and collects particulate matter in exhaust gas, exhausted from the internal combustion engine, to purify the exhaust gas.
  • This exhaust gas purification filter includes a honeycomb structure including: an outer peripheral wall; a porous cell wall that is provided in the outer peripheral wall in a polygonal lattice shape; and plural cells that are partitioned in the cell wall.
  • the inflow gas-side cell functions as an intake side flow path through which exhaust gas is taken in
  • the exhaust side cell functions as an exhaust side flow path through which the exhaust gas having passed through the cell wall is exhausted.
  • a PM combustion catalyst containing Ag and an oxidation catalyst are supported, the PM combustion catalyst is formed of a catalyst material obtained by dispersing Ag in a layered alumina, and the oxidation catalyst oxidizes at least CO in the exhaust gas.
  • the PM combustion catalyst is supported without the oxidation catalyst being supported.
  • at least the oxidation catalyst is supported.
  • JP 2012-219715 A discloses an exhaust gas control apparatus including an oxidation catalyst.
  • This oxidation catalyst includes a support and a silver-containing material supported on the support.
  • the support is formed of at least one metal salt selected from the group consisting of sulfate and phosphate of Ca.
  • the silver-containing material is at least one selected from the group consisting of silver, silver oxide, silver carbonate, silver sulfate, and silver phosphate.
  • an exhaust gas control apparatus can be provided, in which a decrease in particulate matter oxidation performance due to ash deposition is sufficiently suppressed, and the particulate matter oxidation performance is also superior after ash deposition.
  • the requirements in an exhaust gas purification catalyst have increased, and an exhaust gas purification catalyst capable of exhibiting sufficiently high PM oxidation activity even when being exposed to gas containing sulfur has been required.
  • the invention provides an exhaust gas purification catalyst capable of exhibiting sufficiently high PM oxidation activity even when being exposed to gas containing sulfur, and an exhaust gas purification filter and an exhaust gas purification method using the same.
  • the present inventors have found that, by causing an active species fine particle containing silver sulfate as a major component to be supported on a surface of a support containing alumina as a major component, surprisingly, the obtained exhaust gas purification catalyst can exhibit sufficiently high PM oxidation activity even when being exposed to gas containing sulfur. Based on this finding, the invention has been completed.
  • an exhaust gas purification catalyst includes: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component and having an average crystallite size of 3 nm to less than 100 nm, in which the active species fine particle is supported on a surface of the support.
  • a support amount of the silver sulfate with respect to a total amount of the support and the active species fine particle may be 2 mass % to 50 mass % in terms of metal silver.
  • a specific surface area of the support may be 5 m 2 /g to 300 m 2 /g.
  • an exhaust gas purification filter includes: an air-permeable substrate; and an exhaust gas purification catalyst according to the above aspect of the invention supported on the air-permeable substrate.
  • an exhaust gas purification method includes oxidizing and removing particulate matter (PM) by bringing exhaust gas exhausted from an internal combustion engine into contact with the exhaust gas purification catalyst according to the above aspect of the invention.
  • PM particulate matter
  • silver sulfate which is used while being supported on the surface of the support containing alumina as a major component is less likely to be affected by sulfur poisoning as compared to metal silver or silver oxide.
  • silver sulfate used as the active species fine particle has higher dispersibility on alumina used as the support as compared to metal silver or silver oxide, the contact probability thereof with particulate matter (PM) is improved, and thus sufficiently high PM oxidation activity is exhibited.
  • silver sulfate as an active species is stable on the surface of the support containing alumina as a major component even at a high temperature and is not likely to be decomposed.
  • FIGS. 1A to 1D are schematic diagrams showing initial states of exhaust gas purification catalysts and states thereof during sulfur poisoning regeneration.
  • FIGS. 1A to 1D are schematic diagrams showing initial states of exhaust gas purification catalysts and states thereof during sulfur poisoning regeneration.
  • An oxygen active species is adsorbed on a surface of the silver (Ag) particle, this oxygen active species is transferred to particulate matter (PM) through the alumina support, and this oxygen active species can oxidize the PM.
  • the exhaust gas purification catalyst of the related art is exposed to gas containing sulfur, as shown in FIG. 1D , a portion of the silver particle supported on the surface of the alumina support may be converted into silver sulfate due to sulfur poisoning.
  • the oxygen active species cannot be adsorbed on the surface of the sulfur-poisoned Ag particle.
  • the Ag particle is coarse, the contact probability of silver sulfate, which is produced on a portion of the surface of Ag supported on the surface of the alumina support, with the PM is low.
  • the active species fine particle containing silver sulfate as a major component and having an average crystallite size of 3 nm to less than 100 nm is supported on the surface of the support containing alumina as a major component.
  • oxygen of a silver sulfate fine particle which is the active species fine particle supported on the surface of the support such as alumina can be used to oxidize particulate matter (PM) near the silver sulfate fine particle.
  • Oxygen of the silver sulfate fine particle is used for the oxidation when particulate matter (PM) approaches the silver sulfate fine particle.
  • the average crystallite size of the active species fine particle containing silver sulfate as a major component is sufficiently small at 3 nm to less than 100 nm. Therefore, the present inventors presume that, when the exhaust gas purification catalyst according to the invention is exposed to gas containing sulfur, the contact probability with particulate matter (PM) is sufficiently maintained even after sulfur poisoning regeneration, and high PM oxidation activity can be maintained.
  • the present inventors presume that, in the exhaust gas purification catalyst according to the invention in which the active species fine particle containing silver sulfate as a major component and having an average crystallite size of 3 nm to less than 100 nm is supported on the surface of the support containing alumina as a major component, due to the above-described actions, sufficiently high PM oxidation activity is exhibited even when being exposed to gas containing sulfur.
  • an exhaust gas purification catalyst capable of exhibiting sufficiently high PM oxidation activity even when being exposed to gas containing sulfur; and an exhaust gas purification filter and an exhaust gas purification method using the same can be provided.
  • FIG. 1A to 1D are schematic diagrams showing initial states of exhaust gas purification catalysts and states thereof during sulfur poisoning regeneration, in which FIG. 1A is a schematic diagram showing an initial state of an exhaust gas purification catalyst according to the invention, FIG. 1B is a schematic diagram showing a state of the exhaust gas purification catalyst according to the invention during sulfur poisoning regeneration, FIG. 1C is a schematic diagram showing an initial state of an exhaust gas purification catalyst of the related art, and FIG. 1D is a schematic diagram showing a state of the exhaust gas purification catalyst of the related art during sulfur poisoning regeneration;
  • FIG. 2 is a graph showing the PM 50% oxidation temperatures of exhaust gas purification catalysts in the initial state obtained in Examples 1 and 2 and Comparative Examples 1 to 7;
  • FIG. 3 is a graph showing the PM 50% oxidation temperatures of exhaust gas purification catalysts after a sulfur poisoning regeneration treatment obtained in Examples 1 and 2 and Comparative Examples 1 to 3, 6, and 7.
  • the exhaust gas purification catalyst according to the embodiment of the invention includes: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component, in which the active species fine particle is supported on a surface of the support.
  • the exhaust gas purification catalyst according to the embodiment of the invention can be suitably adopted as a PM oxidation catalyst which oxidizes and removes particulate matter (PM) in exhaust gas, which is exhausted from an internal combustion engine such as a diesel engine, to purify the exhaust gas. More preferably, the exhaust gas purification catalyst according to the embodiment of the invention can be adopted as a diesel PM oxidation catalyst.
  • the support according to the embodiment of the invention is a support containing alumina (Al 2 O 3 ) as a major component.
  • This support containing alumina as a major component is not particularly limited as long it contains alumina as a major component.
  • “containing alumina as a major component” represents the support consisting of only alumina or the support consisting of alumina, which is a major component, and other components.
  • compounds other than alumina which can be used as a support of an exhaust gas purification catalyst for the above-described application can be used.
  • the content of the alumina in the support is preferably 90 mass % or more, more preferably 95 mass % or more, and still more preferably 98 mass % or more with respect to 100 mass % of the total mass of the support.
  • the content of alumina in the support is less than the lower limit, silver sulfate reacts with the support, and thus the activity decreases.
  • Alumina as the support may be at least one alumina selected from the group consisting of boehmite alumina, pseudo-boehmite alumina, ⁇ -alumina, ⁇ -alumina, ⁇ -alumina, ⁇ -alumina, pseudo- ⁇ -alumina, ⁇ -alumina, ⁇ -alumina, and ⁇ -alumina. From the viewpoint of heat resistance, ⁇ -alumina or ⁇ -alumina is preferably used, and ⁇ -alumina having high activity is more preferably used.
  • oxides of metals can be used, the metals including: rare earth metals such as yttrium (Y), lanthanum (La), praseodymium (Pr), cerium (Ce), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), scandium (Sc), and vanadium (V); alkali metals; alkali earth metals; and transition metals.
  • rare earth metals such as yttrium (Y), lanthanum (La), praseodymium (Pr), cerium (Ce), neodymium (Nd), prome
  • the support containing alumina as a major component is a support containing 90 mass % or more of alumina with respect to 100 mass % of the total mass of the support and an oxide of at least one metal selected from the group consisting of yttrium (Y), lanthanum (La), praseodymium (Pr), cerium (Ce), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), scandium (Sc), and vanadium (V).
  • Y yttrium
  • La lanthanum
  • Pr praseodymium
  • Ce cerium
  • the specific surface area of the support containing alumina as a major component is not particularly limited, but is preferably 5 m 2 /g to 300 m 2 /g and more preferably 8 m 2 /g to 200 m 2 /g.
  • the specific surface area is more than the upper limit, the heat resistance of the support decreases, and thus the heat resistance of the catalyst tend to decrease.
  • the specific surface area is less than the lower limit, the dispersibility of the active species fine particle (silver sulfate) decreases.
  • the specific surface area can be calculated from an adsorption isotherm as a BET specific surface area using a BET isotherm adsorption equation.
  • the shape of the support containing alumina as a major component is not particularly limited and may be a well-known shape of the related art such as a ring shape, a spherical shape, a cylindrical shape, or a pellet shape. It is preferable that the active species fine particle is particulate from the viewpoint of adopting the form having high dispersibility.
  • the average primary particle size of particles of the support is preferably 1 nm to 300 nm and more preferably 3 nm to 200 nm.
  • the average primary particle size of the support can be measured by being calculated using Scherrer's equation after obtaining the line width of a powder X-ray diffraction peak using an X-ray diffractometer.
  • the average secondary particle size of particles of the support is preferably 0.05 ⁇ m to 100 ⁇ m and more preferably 0.1 ⁇ m to 10 ⁇ m.
  • the average secondary particle size is less than the lower limit, the particles are likely to aggregate in a high-temperature atmosphere, and thus the catalytic activity decreases.
  • the average secondary particle size is more than the upper limit, the contact with PM is lost. Therefore, the activity decreases, and it is difficult to support the particles on the filter.
  • the average secondary particle size of the support can be measured using a laser diffraction particle size distribution analyzer.
  • the average particle size of powder of the support containing alumina as a major component in the catalyst may be changed.
  • a method of producing the support is not particularly limited, but a well-known method capable of producing the support containing alumina as a major component can be appropriately used.
  • a support for example, a commercially available alumina or a composite oxide containing alumina as a major component may be used.
  • the size of the support may be appropriately adjusted by milling with a ball mill or the like.
  • the active species fine particle according to the embodiment of the invention is supported on the surface of the support containing alumina as a major component. It is necessary that this active species fine particle contains silver sulfate (Ag 2 SO 4 ) as a major component and has an average crystallite size of 3 nm to less than 100 nm.
  • the active species fine particle is not particularly limited as long as it contains silver sulfate (Ag 2 SO 4 ) as a major component and has an average crystallite size of 3 nm to less than 100 nm.
  • containing silver sulfate as a major component represents the active species fine particle consisting of only silver sulfate (Ag 2 SO 4 ) or the active species fine particle consisting of silver sulfate (Ag 2 SO 4 ), which is a major component, and other components.
  • the other components for example, compounds other than alumina which can be used as a supported material of an exhaust gas purification catalyst for the above-described application can be used.
  • the content of silver sulfate (Ag 2 SO 4 ) in the active species fine particle is preferably 80 mass % or more, more preferably 90 mass % or more, and still more preferably 95 mass % or more with respect to 100 mass % of the total mass of the active species fine particle.
  • the content of silver sulfate (Ag 2 SO 4 ) in the active species fine particle is less than the lower limit, the resistance to sulfur poisoning decreases.
  • examples of other components other than silver sulfate, which are contained in the active species fine particle containing silver sulfate (Ag 2 SO 4 ) as a major component include metal silver (Ag), silver oxide, silver carbonate, silver sulfite, silver thiosulfate, and silver halide.
  • the active species fine particle containing silver sulfate as a major component is used.
  • the dispersibility of silver sulfate on the surface of the alumina support is high, the contact probability between silver sulfate (Ag 2 SO 4 ) as the active species and particulate matter (PM) is improved, and thus sufficiently high PM oxidation activity can be exhibited.
  • silver sulfate (Ag 2 SO 4 ) as the active species has high dispersibility on the surface of the alumina support, is stable even at a high temperature, and thus is not likely to be decomposed and is less likely to be affected by sulfur poisoning. As a result, even when the catalyst is exposed to gas containing sulfur, high PM oxidation activity can be maintained, and sufficiently high PM oxidation activity can be exhibited.
  • the type of the support and silver sulfate and the like of the active species fine particle supported on the support can be verified by obtaining an X-ray diffraction pattern through X-ray diffraction measurement and then obtaining the types of existing crystals from the peak positions.
  • the average crystallite size (average primary particle size) of silver sulfate or the active species fine particle containing silver sulfate as a major component be 3 nm to less than 100 nm.
  • the average crystallite size of silver sulfate or the active species fine particle containing silver sulfate as a major component is less than the lower limit, the stability of silver sulfate is insufficient.
  • the average crystallite size is 100 nm or more, the dispersibility decreases, and the contact with PM is insufficient.
  • the average crystallite size of the active species fine particle is preferably 5 nm to 80 nm and more preferably 10 nm to 50 nm.
  • the average crystallite size (average primary particle size) of silver sulfate or the active species fine particle containing silver sulfate as a major component can be measured by being calculated using Scherrer's equation after obtaining the line width of a powder X-ray diffraction peak using an X-ray diffractometer.
  • the support amount of silver sulfate used in the embodiment of the invention is not particularly limited, but is preferably 2 mass % to 50 mass %, more preferably 5 mass % to 30 mass %, and still more preferably 7.5 mass % to 15 mass % in terms of silver (metal) with respect to the total amount of the support and the active species fine particle.
  • the support amount of silver sulfate is less than the lower limit, the particulate matter oxidation performance is not sufficiently high.
  • the support amount of silver sulfate is more than the upper limit, the oxidation performance is saturated, and thus the cost increases.
  • the average secondary particle size of silver sulfate or the active species fine particle containing silver sulfate as a major component is not particularly limited, but is preferably 3 nm to 300 nm, more preferably 5 nm to 100 nm, and still more preferably 10 nm to 50 nm.
  • the average secondary particle size of silver sulfate or the active species fine particle containing silver sulfate as a major component is less than the lower limit, the stability of silver sulfate decreases. On the other hand, when the average secondary particle size is more than the upper limit, the contact probability with PM decreases.
  • the average secondary particle size of silver sulfate or the active species fine particle containing silver sulfate as a major component can be measured using a laser diffraction particle size distribution analyzer.
  • a method of causing the active species fine particle to be supported on the support containing alumina as a major component is not particularly limited, and a well-known method can be appropriately used.
  • the active species fine particle is caused to be supported on the support by appropriately adopting methods including: a method of coating (optionally, followed by firing) the surface of the support with a dispersion or sol of the active species fine particle containing silver sulfate (Ag 2 SO 4 ) as a major component or of a precursor thereof; and a vapor deposition method (for example, a chemical vapor deposition method, a physical vapor deposition method, or a sputter deposition method).
  • the exhaust gas purification catalyst according to the embodiment of the invention only needs to include: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component, in which the active species fine particle is supported on a surface of the support.
  • the form of the exhaust gas purification catalyst is not particularly limited, and may be a pellet form or a form of being supported on a filter.
  • a method of producing the exhaust gas purification catalyst according to the embodiment of the invention is not particularly limited, and a well-known method can be appropriately used.
  • the exhaust gas purification catalyst is produced using a method including: a step of impregnating the surface of the support containing alumina as a major component with an aqueous solution containing ions of the active species fine particle containing silver sulfate as a major component and the like; and a step of heating and firing the support.
  • a method can be adopted, the method including: bringing the support containing alumina as a major component into contact with a solution containing silver sulfate (Ag 2 SO 4 ) in a predetermined concentration to impregnate (support) the support with the solution containing a predetermined amount of silver sulfate (Ag 2 SO 4 ); and heating and firing the support.
  • a solution containing silver sulfate Ag 2 SO 4
  • the heating and firing (firing step) in the supporting method of the active species fine particle containing silver sulfate as a major component may be performed in air.
  • the firing temperature in the firing step is preferably 200° C. to 700° C.
  • the firing temperature is lower than the lower limit, it is difficult to cause the active species fine particle containing silver sulfate as a major component to be supported on the support, and sufficient PM oxidation activity of the exhaust gas purification catalyst cannot be obtained.
  • the firing temperature is higher than the upper limit, the specific surface area of the support containing alumina as a major component is likely to decrease, and thus the oxidation activity decreases.
  • the firing time is preferably 0.1 hours to 100 hours.
  • the exhaust gas purification catalyst according to the embodiment of the invention exhibits high PM oxidation activity against particulate matter, which is contained in gas (exhaust gas) exhausted from an internal combustion engine, and can oxidize and remove PM. Therefore, an exhaust gas control apparatus can be configured by disposing the exhaust gas purification catalyst so as to be in contact with the exhaust gas.
  • the exhaust gas control apparatus oxidizes and purifies particulate matter (PM) contained in exhaust gas, and the configuration thereof is not particularly limited as long as it includes the exhaust gas purification catalyst according to the invention.
  • the exhaust gas control apparatus In order to oxidize and purify (remove) particulate matter contained in gas (exhaust gas) exhausted from an internal combustion engine, the exhaust gas control apparatus only needs to be disposed so as to be in contact with the exhaust gas.
  • the exhaust gas control apparatus may have a configuration of being disposed at a gas flow path inside an exhaust gas pipe through which exhaust gas exhausted from an internal combustion engine flows.
  • the internal combustion engine is not particularly limited, and a well-known internal combustion engine such as an automobile engine (for example, a gasoline engine or a diesel engine) may be used.
  • the exhaust gas purification catalyst according to the invention is supported on an air-permeable substrate (filter).
  • the exhaust gas purification filter according to the embodiment of the invention is not particularly limited as long as the exhaust gas purification catalyst according to the invention is supported on the air-permeable substrate.
  • a well-known air-permeable substrate (filter) can be appropriately used, and examples thereof include a particulate filter, a monolithic filter, a honeycomb filter, a pellet filter, a plate filter, and a ceramic foam filter.
  • the exhaust gas purification catalyst according to the embodiment of the invention is supported on an air-permeable substrate (filter), it is more preferable that the exhaust gas purification catalyst according to the embodiment of the invention is supported on a particulate filter because higher particulate matter (PM) oxidation performance than before can be obtained.
  • PM particulate matter
  • the material of the air-permeable substrate of the exhaust gas purification filter is not particularly limited, and a well-known material can be appropriately used.
  • the well-known material include ceramics such as cordierite, silicon carbide, mullite, and aluminum titanate; and metals such as stainless steel containing chromium and aluminum.
  • the exhaust gas purification filter has pores having an average pore size of 1 ⁇ m to 300 ⁇ m.
  • the substrate having the above-described average pore size particulate matter can be oxidized and purified more efficiently.
  • a coating layer formed of the exhaust gas purification catalyst according to the embodiment of the invention is formed.
  • the thickness of the coating layer is preferably 0.025 ⁇ m to 25 ⁇ m and more preferably 0.035 ⁇ m to 10 ⁇ m.
  • the surface of the filter cannot be sufficiently coated with the catalyst including: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component, in which the active species fine particle is supported on a surface of the support. Therefore, the number of contact points with particulate matter decreases, and it is difficult to impart sufficiently high oxidation performance.
  • the pores of the filter are blocked by the catalyst including: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component, in which the active species fine particle is supported on a surface of the support. Therefore, the pressure loss of exhaust gas increases, and the engine efficiency decreases.
  • the amount of the catalyst supported on the air-permeable substrate is not particularly limited, and can be appropriately adjusted depending on an internal combustion engine and the like.
  • the amount of the catalyst is preferably 1 g to 300 g and more preferably 10 g to 100 g with respect to 1 L of the volume of the air-permeable substrate.
  • the support amount is less than the lower limit, it is difficult to exhibit sufficiently high catalytic performance.
  • the support amount is more than the upper limit, the pores of the air-permeable substrate are blocked by the catalyst including the support and the silver-containing material, the pressure loss of exhaust gas increases, and the engine efficiency decreases.
  • the exhaust gas purification filter has a porosity of preferably 30% to 70% (more preferably 40% to 65%).
  • “Porosity” described herein refers to a volume ratio of void portions in the air-permeable substrate. When the porosity is lower than the lower limit, the pores are likely to be blocked by particulate matter in exhaust gas. On the other hand, when the porosity is higher than the upper limit, it is difficult to collect particulate matter in exhaust gas, and the strength of the filter decreases.
  • a method of causing the exhaust gas purification catalyst according to the invention to be supported on the air-permeable substrate is not particularly limited, and various methods can be adopted.
  • a method can be adopted, the method including: preparing a catalyst; and causing the catalyst to be supported on an air-permeable substrate.
  • the catalyst includes: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component, in which the active species fine particle is supported on a surface of the support.
  • a method in which a catalyst is caused to be supported on a filter through the following steps including: a step of causing a support to be supported on an air-permeable substrate; and a step of causing the active species fine particle containing silver sulfate as a major component to be supported on the support which is supported on the air-permeable substrate.
  • the catalyst includes: a support containing alumina as a major component; and an active species fine particle containing silver sulfate as a major component which is supported on the surface of the support.
  • a method of causing the catalyst or the support and the active species fine particle to be supported on the air-permeable substrate is not particularly limited, and a well-known method can be appropriately adopted.
  • a method can be appropriately used, the method including: preparing a slurry of the catalyst or the support and the like; and coating (optionally, followed by firing) the air-permeable substrate with this slurry.
  • other well-known components which can be used in a catalyst to oxidize particulate matter may be appropriately used within a range in which the effects of the invention are not impaired.
  • the exhaust gas purification method according to the embodiment of the invention includes: oxidizing and removing particulate matter (PM) by bringing exhaust gas exhausted from an internal combustion engine into contact with the exhaust gas purification catalyst according to the embodiment of the invention.
  • PM particulate matter
  • a method of bringing exhaust gas into contact with the exhaust gas purification catalyst is not particularly limited, and a well-known method can be appropriately used.
  • a method may be adopted, the method including: bringing exhaust gas exhausted from an internal combustion engine into contact with the exhaust gas purification catalyst according to the embodiment of the invention by disposing the exhaust gas purification catalyst inside an exhaust gas pipe through which gas exhausted from an internal combustion engine flows.
  • the exhaust gas purification catalyst according to the embodiment of the invention used in the exhaust gas purification method according to the embodiment of the invention, even when being exposed to gas containing sulfur, high PM oxidation activity can be maintained. Therefore, even when the exhaust gas purification catalyst is exposed to gas containing sulfur, sufficiently high PM oxidation activity can be exhibited.
  • particulate matter (PM) in the exhaust gas can be sufficiently oxidized and removed to purify the exhaust gas. Further, even when the exhaust gas purification catalyst is exposed to gas containing sulfur, particulate matter (PM) in the exhaust gas can be sufficiently oxidized and removed to purify the exhaust gas.
  • the exhaust gas purification method according to the invention can be suitably adopted, for example, as a method of purifying particulate matter (PM) in exhaust gas exhausted from an internal combustion engine such as a diesel engine.
  • a catalyst powder was obtained.
  • this powder was mixed in a mortar and was molded into a pellet shape having a particle size of 0.3 mm to 0.5 mm using an ordinary method (cold isostatic pressing (CIP)).
  • CIP cold isostatic pressing
  • a pellet catalyst (Ag 2 SO 4 / ⁇ -Al 2 O 3 ) was obtained.
  • the support amount of silver sulfate was 10.0 mass % in terms of Ag with respect to the total amount of the ⁇ -Al 2 O 3 support and the active species fine particle formed of silver sulfate.
  • a pellet catalyst (Ag 2 SO 4 / ⁇ -Al 2 O 3 ) was obtained in the same procedure as that of Example 1, except that ⁇ -Al 2 O 3 powder (8.56 g, manufactured by Wako Pure Chemical Industries Ltd., ⁇ -Al 2 O 3 , specific surface area: 8 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver sulfate was 10.0 mass % in terms of Ag with respect to the total amount of the ⁇ -Al 2 O 3 support and the active species fine particle formed of silver sulfate.
  • a catalyst powder for comparison was obtained.
  • this powder was mixed in a mortar and was molded into a pellet shape having a particle size of 0.3 mm to 0.5 mm using an ordinary method (cold isostatic pressing (CIP)).
  • CIP cold isostatic pressing
  • a pellet catalyst (Ag/ ⁇ -Al 2 O 3 ) for comparison was obtained.
  • the support amount of silver was 10 mass % in terms of Ag with respect to the total amount of the ⁇ -Al 2 O 3 support and silver.
  • a pellet catalyst (Ag/CeO 2 ) for comparison was obtained in the same procedure as that of Comparative Example 1, except that CeO 2 powder (9.00 g, manufactured by Anan Kasei Co. Ltd., low-temperature firing cerium, specific surface area: 150 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver was 10 mass % in terms of Ag with respect to the total amount of the CeO 2 support and silver.
  • a pellet catalyst (Ag 2 SO 4 /CeO 2 ) for comparison was obtained in the same procedure as that of Example 1, except that CeO 2 powder (8.56 g, manufactured by Anan Kasei Co. Ltd., low-temperature firing cerium, specific surface area: 150 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver sulfate was 10 mass % in terms of Ag with respect to the total amount of the CeO 2 support and silver sulfate.
  • a pellet catalyst (Ag 2 SO 4 /TiO 2 ) for comparison was obtained in the same procedure as that of Example 1, except that TiO 2 powder (8.56 g, ST-01, manufactured by Ishihara Sangyo Co. Ltd., specific surface area: 300 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver sulfate was 10 mass % in terms of Ag with respect to the total amount of the TiO 2 support and silver sulfate.
  • a pellet catalyst (Ag 2 SO 4 /SiO 2 ) for comparison was obtained in the same procedure as that of Example 1, except that SiO 2 powder (8.56 g, 90G, manufactured by Nippon Aerosil Co. Ltd., specific surface area: 90 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver sulfate was 10 mass % in terms of Ag with respect to the total amount of the SiO 2 support and silver sulfate.
  • this powder was mixed in a mortar and was molded into a pellet shape having a particle size of 0.3 mm to 0.5 mm using an ordinary method (cold isostatic pressing (CIP)).
  • CIP cold isostatic pressing
  • a pellet catalyst Pt/ ⁇ -Al 2 O 3
  • the support amount of platinum (Pt) was 1.0 mass % in terms of Pt with respect to the total amount of the ⁇ -Al 2 O 3 support and Pt.
  • a pellet catalyst (Ag 2 SO 4 /CaSO 4 ) for comparison was obtained in the same procedure as that of Example 1, except that calcium sulfate powder (8.56 g, calcined plaster (manufactured by Wako Pure Chemical Industries Ltd.) which was fired in air at 500° C. for three hours, specific surface area: 5 m 2 /g) was used instead of ⁇ -Al 2 O 3 as the support.
  • the support amount of silver sulfate was 10 mass % in terms of Ag with respect to the total amount of the CaSO 4 support and silver sulfate.
  • Table 1 shows the supports and the supported materials (active species fine particles) used in Examples 1 and 2 and Comparative Examples 1 to 7.
  • a PM oxidation activity measurement test first, using a rotary stand for testing and research, the pellet catalyst in the initial state and carbon powder (manufactured by Tokai Carbon Co., Ltd., trade name: “Seast 9 (SAF)”, average particle size: 19 nm) as simulated particulate (simulated PM) were filled into a cylindrical sample pipe having an inner diameter of 20 mm.
  • the pellet catalyst and the carbon powder were mixed by being rotated in the rotary stand for testing and research for one hour to prepare an evaluation sample.
  • the simulated PM was mixed with the catalyst at a weight ratio (catalyst:simulated PM) of 49:1.
  • “Initial state” described here refers to the state of the catalyst on which both a heat resistance test and a sulfur poisoning regeneration test described below are not performed after the production of the catalyst.
  • FIG. 2 is a graph showing, as the PM oxidation activity of the catalyst in the initial state, the PM 50% oxidation temperatures of exhaust gas purification catalysts in the initial state obtained in Examples 1 and 2 and Comparative Examples 1 to 7.
  • a mixed gas (intake gas) containing SO 2 (66 ppm), O 2 (10%), CO 2 (10%), H 2 O (10%), and N 2 (remainder) was supplied to the device under conditions of 400° C. (intake gas temperature), 55.5 minutes, and a gas flow rate of 7 L/min (sulfur poisoning treatment).
  • the total supply amount of the sulfur component supplied in the sulfur poisoning treatment was 1.0 g/30 g-cat.
  • the catalyst sample after the sulfur poisoning treatment and the carbon powder were mixed in the same procedure as that of the PM mixing treatment I to prepare an evaluation sample.
  • the simulated PM was mixed with the catalyst at a weight ratio (catalyst:simulated PM) of 49:1.
  • the sulfur poisoning regeneration treatment was performed as follows.
  • a mixed gas (intake gas) containing O 2 (10%)+H 2 O (10%)/N 2 (remainder) with respect to the evaluation sample was supplied to the catalyst sample at a gas flow rate of 10 L/min while increasing the intake gas temperature from 120° C. to 720° C. at a temperature increase rate of 20° C./min.
  • the catalyst sample after the sulfur poisoning regeneration treatment and the carbon powder were mixed in the same procedure as that of the PM mixing treatment I to prepare an evaluation sample.
  • the simulated PM was mixed with the catalyst at a weight ratio (catalyst:simulated PM) of 49:1.
  • a mixed gas (intake gas) including O 2 (10%)+H 2 O (10%)/N 2 (remainder) with respect to the evaluation sample was supplied to the catalyst at a gas flow rate of 10 L/min while increasing the intake gas temperature from 120° C. to 720° C. at a temperature increase rate of 20° C./min.
  • the concentration of CO 2 in gas exhausted from the device was measured during a period from the supply start to the supply end of the mixed gas. Based on the concentration of CO 2 in the exhaust gas and the temperature of the intake gas, the temperature of the mixed gas (PM 50% oxidation temperature) required to oxidize 50% of carbon attached to each evaluation sample was calculated as an index of the PM oxidation activity of the catalyst after the sulfur poisoning regeneration treatment.
  • FIG. 3 is a graph showing, as the PM oxidation activity of the catalyst after the sulfur poisoning regeneration treatment, the PM 50% oxidation temperatures of exhaust gas purification catalysts after sulfur poisoning regeneration treatment obtained in Examples 1 and 2 and Comparative Examples 1 to 3, 6, and 7.
  • a powder X-ray diffractometer manufactured by Rigaku Corporation, trade name: “horizontal sample mount X-ray diffractometer RINT-TTR”
  • XRD X
  • an exhaust gas purification catalyst capable of exhibiting sufficiently high PM oxidation activity even when being exposed to gas containing sulfur; and an exhaust gas purification filter and an exhaust gas purification method using the same can be provided. Accordingly, the exhaust gas purification catalyst, and the exhaust gas purification filter and the exhaust gas purification method using the same according to the present invention are particularly useful, for example, as a PM oxidation catalyst for purifying particulate matter in exhaust gas exhausted from an internal combustion engine such as a diesel engine and as an exhaust gas purification filter or an exhaust gas purification method using the same.

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5658542A (en) * 1994-07-15 1997-08-19 Kabushiki Kaisha Riken Exhaust gas cleaner and method for cleaning same
US20050002843A1 (en) * 2003-05-07 2005-01-06 Kocat Inc. Catalytic process for nitrogen oxides reduction by multi-injection and use thereof
US20050288179A1 (en) * 2004-06-24 2005-12-29 Caterpillar Inc. Silver doped catalysts for treatment of exhaust
US20090288400A1 (en) * 2005-10-28 2009-11-26 Yong-Woo Kim Exhaust Gas Purifying Device for Diesel Engine
EP2696047A1 (en) * 2011-04-08 2014-02-12 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification device, and exhaust gas purification method using same

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5714432A (en) * 1992-12-28 1998-02-03 Kabushiki Kaisha Riken Exhaust gas cleaner comprising supported silver or silver oxide particles
JPH06198131A (ja) * 1992-12-28 1994-07-19 Agency Of Ind Science & Technol 窒素酸化物除去材及び窒素酸化物除去方法
JPH0824654A (ja) * 1994-07-15 1996-01-30 Riken Corp 排ガス浄化材及び排ガス浄化方法
EP0770421A1 (en) * 1995-10-25 1997-05-02 Nikki Chemical Co., Ltd. Catalyst for removing nitrogen oxides
US7803338B2 (en) * 2005-06-21 2010-09-28 Exonmobil Research And Engineering Company Method and apparatus for combination catalyst for reduction of NOx in combustion products
JP5350614B2 (ja) 2007-08-22 2013-11-27 本田技研工業株式会社 排ガス浄化触媒及びこれを用いた排ガス浄化装置
WO2010033964A2 (en) * 2008-09-22 2010-03-25 Tufts University Treating catalysts
JP5440339B2 (ja) 2010-04-09 2014-03-12 株式会社デンソー 排ガス浄化フィルタ
CN102658175A (zh) * 2012-05-18 2012-09-12 华东理工大学 一种用于富氧条件下丙烯选择性催化还原NOx的负载银催化剂

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5658542A (en) * 1994-07-15 1997-08-19 Kabushiki Kaisha Riken Exhaust gas cleaner and method for cleaning same
US20050002843A1 (en) * 2003-05-07 2005-01-06 Kocat Inc. Catalytic process for nitrogen oxides reduction by multi-injection and use thereof
US20050288179A1 (en) * 2004-06-24 2005-12-29 Caterpillar Inc. Silver doped catalysts for treatment of exhaust
US20090288400A1 (en) * 2005-10-28 2009-11-26 Yong-Woo Kim Exhaust Gas Purifying Device for Diesel Engine
EP2696047A1 (en) * 2011-04-08 2014-02-12 Toyota Jidosha Kabushiki Kaisha Exhaust gas purification device, and exhaust gas purification method using same

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