WO2017119101A1 - フィルター - Google Patents
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- WO2017119101A1 WO2017119101A1 PCT/JP2016/050353 JP2016050353W WO2017119101A1 WO 2017119101 A1 WO2017119101 A1 WO 2017119101A1 JP 2016050353 W JP2016050353 W JP 2016050353W WO 2017119101 A1 WO2017119101 A1 WO 2017119101A1
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- WIPO (PCT)
- Prior art keywords
- catalyst
- filter
- filter according
- cells
- base material
- Prior art date
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- 239000003054 catalyst Substances 0.000 claims abstract description 62
- 239000000463 material Substances 0.000 claims abstract description 56
- 238000005192 partition Methods 0.000 claims abstract description 35
- 239000000126 substance Substances 0.000 claims abstract description 23
- 239000011148 porous material Substances 0.000 claims description 43
- 239000007789 gas Substances 0.000 claims description 33
- 239000002585 base Substances 0.000 claims description 23
- 239000002245 particle Substances 0.000 claims description 20
- 239000000758 substrate Substances 0.000 claims description 12
- 229910052763 palladium Inorganic materials 0.000 claims description 9
- 229910052697 platinum Inorganic materials 0.000 claims description 9
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 230000003197 catalytic effect Effects 0.000 claims description 8
- 229910000510 noble metal Inorganic materials 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 8
- 239000011232 storage material Substances 0.000 claims description 8
- 229910052783 alkali metal Inorganic materials 0.000 claims description 6
- 150000001340 alkali metals Chemical class 0.000 claims description 6
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 17
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 17
- 238000002485 combustion reaction Methods 0.000 description 15
- 238000000034 method Methods 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 238000011049 filling Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 238000000746 purification Methods 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000010953 base metal Substances 0.000 description 4
- 239000003575 carbonaceous material Substances 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 239000010931 gold Substances 0.000 description 4
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 4
- 229910052753 mercury Inorganic materials 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 229910052792 caesium Inorganic materials 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 3
- 229910052737 gold Inorganic materials 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 229910052700 potassium Inorganic materials 0.000 description 3
- 230000001737 promoting effect Effects 0.000 description 3
- 238000001878 scanning electron micrograph Methods 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 150000003624 transition metals Chemical group 0.000 description 3
- 229910052684 Cerium Inorganic materials 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000004453 electron probe microanalysis Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000010948 rhodium Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910000505 Al2TiO5 Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 241001124569 Lycaenidae Species 0.000 description 1
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910052777 Praseodymium Inorganic materials 0.000 description 1
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052741 iridium Inorganic materials 0.000 description 1
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 238000007561 laser diffraction method Methods 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052762 osmium Inorganic materials 0.000 description 1
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- AABBHSMFGKYLKE-SNAWJCMRSA-N propan-2-yl (e)-but-2-enoate Chemical compound C\C=C\C(=O)OC(C)C AABBHSMFGKYLKE-SNAWJCMRSA-N 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000004071 soot Substances 0.000 description 1
- JBQYATWDVHIOAR-UHFFFAOYSA-N tellanylidenegermanium Chemical compound [Te]=[Ge] JBQYATWDVHIOAR-UHFFFAOYSA-N 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Images
Classifications
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- 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
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2418—Honeycomb filters
- B01D46/2425—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material
- B01D46/2429—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material of the honeycomb walls or cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2418—Honeycomb filters
- B01D46/2425—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material
- B01D46/24491—Porosity
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
- B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
- B01D46/2418—Honeycomb filters
- B01D46/2425—Honeycomb filters characterized by parameters related to the physical properties of the honeycomb structure material
- B01D46/24492—Pore diameter
-
- 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
- B01D2255/102—Platinum group metals
- B01D2255/1021—Platinum
-
- 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
- B01D2255/102—Platinum group metals
- B01D2255/1023—Palladium
-
- 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
- B01D2255/102—Platinum group metals
- B01D2255/1025—Rhodium
-
- 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
- B01D2255/102—Platinum group metals
- B01D2255/1026—Ruthenium
-
- 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
- B01D2255/102—Platinum group metals
- B01D2255/1028—Iridium
-
- 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
- B01D2255/10—Noble metals or compounds thereof
- B01D2255/106—Gold
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/90—Physical characteristics of catalysts
- B01D2255/908—O2-storage component incorporated in the catalyst
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/90—Physical characteristics of catalysts
- B01D2255/915—Catalyst supported on particulate filters
- B01D2255/9155—Wall flow filters
Definitions
- the present invention relates to a filter.
- the inventor of the present invention uses an on-wall type catalyst in which a catalytic substance is loaded on the surface of the partition wall of the filter cell. It has been found that the coating method has a problem that the PM collection efficiency is low because the amount of PM that can be collected inside the cell is reduced. On the other hand, when the catalyst substance is simply applied to the inside of the porous partition wall, in the in-wall type, if the coating amount is too large, the porosity of the partition wall decreases, and the PM collection efficiency decreases. Moreover, it discovered that there existed a problem that the PM oxidation efficiency by a catalyst also fell.
- the present invention has been made in view of the above background, and an object of the present invention is to provide a filter capable of ensuring the processing efficiency by a catalyst without impairing the performance related to the PM collection efficiency.
- a plurality of cells including a base material and a catalytic substance provided in the base material, wherein the base material has a gas inflow end and an outflow end and serves as a gas flow path. And a plurality of porous partition walls that define these cells, at least a part of the cells is plugged, and the filter has a pore occupancy of 10% or less in the pores of the partition walls Provided.
- the catalyst material has an average particle diameter D50 that is equal to or less than one tenth of the average pore diameter D50 of the pores of the partition walls.
- the ratio of the concentration of the noble metal contained in the catalytic substance at the gas inflow end and the outflow end is 10/90 to 90/10.
- the catalyst material is included in the range of 10% to 50% of the total length in the length direction of the partition wall from the gas inflow side end.
- the filter further includes at least one material selected from the group consisting of an oxygen storage material, an alkali metal, and a perovskite type material.
- the porosity of the base material is 40% to 70%.
- the vacancy occupation rate of the catalyst is less than 5%.
- the present invention can provide a filter that can ensure the processing efficiency by the catalyst without impairing the performance related to the PM collection efficiency.
- the filter according to this embodiment includes a base material 1 and a catalytic substance 2 provided in the base material 1, and the base material 1 has a gas inflow side end 2 and an outflow side end 3. And a plurality of porous partition walls 5 that define the cells 4, and at least some of the ends of the cells 4 are sealed, and pores (not shown) of the partition walls
- the vacancy occupancy rate of the catalyst material (not shown) is 10% or less.
- the filter according to the present embodiment can ensure the processing efficiency by the catalyst without impairing the performance related to the PM collection efficiency.
- the filter according to this embodiment includes a base material 1 and a catalyst material provided in the base material, as illustrated in FIG.
- the base material 1 supports a catalyst substance, and is preferably durable without reducing the combustion efficiency of the connected engine.
- the material constituting the substrate 1 is not particularly limited as long as at least the partition walls 5 can be provided with pores.
- a porous ceramic material is preferably used. .
- Examples of the material of the substrate 1 include cordierite ceramics, silicon carbide, aluminum titanate, and the like composed of three components of aluminum oxide (Al 2 O 3 : alumina), silicon dioxide (SiO 2 : silica) and magnesium oxide (MgO). preferable.
- Al 2 O 3 aluminum oxide
- SiO 2 silicon dioxide
- MgO magnesium oxide
- the substrate 1 preferably has a honeycomb shape made of these materials.
- a honeycomb-shaped filter includes a plurality of cells serving as gas flow paths, but the cross-sectional shape of the cells is not particularly limited, and may be, for example, a grid pattern as shown in FIG. 1 or a hexagonal shape. Good, but not limited by its shape. Or what is called an asymmetrical cell structure from which the size of the cell of an entrance / exit differs may be used.
- the structure of the base material 1 is not limited, but at least the base material 1 has a gas inflow side end 2 and an outflow side end 3.
- the substrate 1 includes at least a plurality of cells 4 serving as gas flow paths and a plurality of porous partition walls 5 defining the cells 4.
- the filter according to the present embodiment at least some of the end portions of the cells 4 are partially sealed with respect to the plurality of cells 4.
- the gas flowing in from the inflow side end 2 moves inside the cell 4 without passing through the partition wall, and part of the gas passes through the hole of the partition wall 5 and flows out. It flows out from the side end 3.
- the ratio of the sealed cells is not limited, and the arrangement of the sealed cells is not limited.
- the filter according to the present embodiment preferably employs a base material having the above-described configuration, but the base material supporting the catalyst substance is not limited to these configurations.
- the catalyst substance is supported and held on the surface of the substrate 1 and is composed of an active metal, an active metal carrier, a catalyst auxiliary, and the like.
- the active metal functions as a catalytically active component of the oxidation catalyst.
- Active metals include noble metals and base metals, preferably noble metals. Specific examples of the noble metal include platinum (Pt), palladium (Pd), rhodium (Rh), ruthenium (Ru), iridium (Ir), osmium (Os), gold (Au), and silver (Ag). Platinum, palladium, or gold is more preferably used. Moreover, these noble metals can be used as a 1 type, or 2 or more types of mixture, According to the preferable aspect of this invention, the mixture of platinum and palladium and the mixture of platinum, palladium, and gold are more preferable.
- the base metal examples include copper (Cu), iron (Fe), cobalt (Co), zinc (Zn), potassium (K), cesium (Cs), silver (Ag), a so-called oxygen storage material made of a rare earth metal. And perovskites composed of Fe, Mn, Y, Ce, La, and the like. Among these, alkali metals, oxygen storage materials, and iron are more preferable. Moreover, these base metals can be used as a 1 type, or 2 or more types of mixture.
- the occupancy rate of the catalyst material in the pores of the plurality of porous partition walls is 10% or less.
- the occupancy rate of the catalyst material in the pores of the plurality of porous partition walls is 10% or less.
- the presence of a catalyst material having a pore occupancy of 10% or less inside the pores of the partition walls 5 can suppress the passage resistance of the gas flowing inside the cell 4 and secure the PM component collection capacity. Can be compatible.
- the shape of the pores and the hole occupation ratio of the catalyst substance can be determined using SEM (scanning electron microscope) / EPMA (electron beam microanalyzer).
- SEM scanning electron microscope
- EPMA electron beam microanalyzer
- the pore area (A) of the base material before application of the catalyst substance can be obtained by image processing (illustrated in FIG. 2) with a field of view of 150 to 500 times by SEM / EPMA.
- the pore area (B) after catalyst application can also be calculated
- the ratio of the pore area of the pores of the base material 1 and the area occupation ratio can be calculated by obtaining the area of the base material portion by image processing in the same two-dimensional method.
- the mercury intrusion method is used as a three-dimensional pore structure volume measurement method.
- the correlation between this method and the above-mentioned method is as shown in FIG. 3, and is obtained from the SEM image.
- an EPM image with a magnification of 150 to 200 is preferably used.
- the occupied area can be obtained by separating the occupied area of the base material and the catalyst by color by the RGB method.
- the filter according to the present embodiment when the occupation area is obtained by image processing, the image is binarized, and calculation is performed in an automatic mode or the like in order to prevent an artificial error.
- the average particle diameter D50 of the catalyst material is 1/10 or less of the average pore diameter D50 of the pores of the partition walls 5.
- the average particle diameter D50 of the catalyst substance can be specifically measured by a laser diffraction method or the like. Specifically, the average pore diameter D50 of the pores of the partition walls 5 can be measured by a mercury porosimeter method. For example, when the average pore diameter D50 of the pores of the partition walls 5 is 10 ⁇ m, the average particle diameter D50 of the catalyst substance is preferably 0.5 ⁇ m or less.
- average particle diameter D50 means a particle diameter (median diameter) corresponding to the median value (50%) of the particle size distribution of the particles.
- the average pore diameter D50 of the pores of the partition walls 5 is preferably 8 ⁇ m to 20 ⁇ m, and more preferably 10 ⁇ m or more from the viewpoint that the collection efficiency of the carbonaceous material is large from the beginning.
- the average particle diameter D50 of the catalyst material is preferably 1/10 or less of the average pore diameter of the partition walls, but preferably has an average particle diameter of 20 nm or more for reasons such as the stability of the dispersion state of the solid content in the catalyst slurry. .
- the amount of the catalyst substance may have a gradient in the length direction of the base material, but the pore occupancy rate of the catalyst is preferably 10% or less.
- the amount of the catalytic substance means the concentration of active metal such as Pt or Pd acting as a catalyst. That is, the active metal concentration has a gradient in the length direction of the substrate, and the ratio of the active metal concentration at the gas inflow end portion to the gas outflow end portion is 10/90 to 90/10. Good.
- the base metal on this filter can contribute to exhaust gas purification.
- the concentration on the outflow side is high, for example, it is effective to supply NO 2 or the like downstream. is there.
- the PM collection efficiency and the treatment with the catalyst are performed in a state where the catalyst is localized at the inflow side end 2 and the outflow side end 3. It can suppress that efficiency falls.
- the catalyst material is preferably included in the range of 10% to 50% of the total length in the length direction of the partition walls from the gas inflow side end.
- the coating range is from the end portion on the gas inflow side, and no catalyst substance is provided on the gas outflow side.
- Pt and Pd are contained as a catalyst material in a ratio of 1: 1 to 10: 1.
- the effect that the thermal sintering (aggregation) of a noble metal can be suppressed is acquired. More preferably, Pt and Pd are included in a ratio of 2: 1 to 5: 1.
- a PM combustion catalyst composed of a noble metal and a transition metal group may be used in combination, or only a PM combustion catalyst composed of a transition metal group may be applied, or a mixture of both may be used.
- the filter according to this embodiment preferably further includes at least one material selected from the group consisting of an oxygen storage material, an alkali metal, and a perovskite type material as a catalyst auxiliary.
- a PM combustion catalyst comprising such a transition metal group, the effect of promoting the combustion of the carbonaceous material can be obtained.
- oxygen storage materials include materials containing Ce, Pr, Zr, and Nd. Among these, Ce is particularly preferably used for the reason of promoting combustion.
- alkali metals examples include K, Cs, and Mg.
- K and Cs are particularly preferably used for the reason of promoting combustion.
- perovskite type material examples include Bi 4 Ti 3 O 4 (Japanese Patent Laid-Open No. 2010-69471) and Ce 0.5 Bi 0.1 Pr 0.4 (Japanese Patent Laid-Open No. 2009-112907).
- oxygen storage materials alkali metals, and perovskite materials
- the most preferable one is an oxygen storage material.
- the filter according to the present embodiment it is preferable that only one of the gas inflow end and the outflow end is partially sealed. With such a configuration, it is possible to obtain an effect that the filter is less likely to be clogged in an actual market.
- the porosity of the substrate 1 is preferably 40% to 70%. By setting it as such a structure, the effect of coexistence of low pressure loss and a carbonaceous material collection capacity
- the hole occupation ratio of the holes of the partition walls 5 by the catalytic material by image processing is less than 10%. By setting it as such a structure, the effect that the fall of PM collection efficiency and a pressure loss raise can be suppressed is acquired. More preferably, the hole occupation ratio of the pores of the partition walls 5 by the catalyst material is less than 5%.
- the filter according to the present embodiment is used for purifying exhaust gas, and the apparatus using the filter according to the present embodiment is used for an internal combustion engine, in particular, a spark ignition type engine (for example, a gasoline engine), a compression ignition type engine (for example, for example). , Diesel engine).
- a spark ignition type engine for example, a gasoline engine
- a compression ignition type engine for example, for example.
- Diesel engine for example, Diesel engine
- these engines may be engines that adjust the air-fuel ratio and burn fuel, and preferred examples thereof include lean burn engines, direct injection engines, and preferably combinations of these engines (ie, direct injection).
- Type lean burn engine is an engine that employs a fuel supply system that can achieve a high compression ratio, an improvement in combustion efficiency, and a reduction in exhaust gas. For this reason, when combined with a lean burn engine, it is possible to further improve the combustion efficiency and reduce the exhaust gas.
- the filter according to this embodiment is preferably used for an exhaust system of an internal combustion engine mounted on a transporter, a machine, or the like.
- transporters and machines include transporters and transporters of machines such as automobiles, buses, trucks, dump trucks, airway cars, motorcycles, motorbikes, ships, tankers, motor boats, airplanes, etc.
- Agricultural and forestry industrial machines such as cultivators, tractors, combine harvesters, chain saws, timber carriers, etc .; marine fishery machines such as fishing boats;
- the filter according to the present embodiment can be installed as a start catalyst, an under floor, or a manifold converter.
- the average particle size (D50) is 0.02 ⁇ m, 0.5 ⁇ m, 2.1 ⁇ m or 4.5 ⁇ m against a DPF (diesel particulate filter) substrate (diameter 143.8 mm, length 152.4 mm).
- a slurry containing alumina particles was coated at 11 g / L, dried and fired at 500 ° C. to prepare a catalyst-supported DPF.
- the pressure loss (BP) under 300 kg / h air circulation was measured.
- FIG. 4 is a graph showing the relationship between the catalyst particle diameter (D50) and the pressure loss (BP) for a DPF having an average pore diameter of 10 ⁇ m. From this graph, it is understood that particles having an average particle diameter of about 0.5 ⁇ m or less are desirable for a DPF having an average pore diameter of 10 ⁇ m.
- Example 2 Three types of catalyst-supported CSFs (catalyzed soot filters) were prepared using alumina particles having an average particle size of 0.02 ⁇ m and catalyst amounts of 11 g / L, 25 g / L, and 45 g / L.
- the filling rate of the pores of each catalyst-supporting CSF was obtained by a method based on image processing, and the PM collection efficiency was measured with a PM generator. The result is shown in FIG. From the results shown in FIG. 5, it can be seen that the PM collection efficiency decreases as the pore filling rate increases.
- Example 3 The pressure loss was measured using the catalyst-supported CSF prepared in Example 2. The result is shown in FIG. From the results of FIG. 6, it can be seen that the pressure loss increases with an increase in the pore filling rate. From the viewpoint of PM combustion, it is desirable that a catalyst be present, but from the results of Examples 2 and 3, it can be seen that it is preferable that the filter substrate has a lower pore filling rate.
- FIG. 7 is a graph showing the relationship between the Pt / Pd ratio and the combustion temperature.
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- Oil, Petroleum & Natural Gas (AREA)
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- Environmental & Geological Engineering (AREA)
- Biomedical Technology (AREA)
- Health & Medical Sciences (AREA)
- Combustion & Propulsion (AREA)
- Catalysts (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Filtering Materials (AREA)
- Processes For Solid Components From Exhaust (AREA)
- Treating Waste Gases (AREA)
- Filtering Of Dispersed Particles In Gases (AREA)
Abstract
Description
一方、単に多孔質の隔壁の内部に触媒物質を塗布する場合イン・ウォール(in-wall)タイプでは、塗布量が多すぎると隔壁の多孔性が低下し、PMの捕集効率が低下し、また触媒によるPM酸化効率も低下するという問題があることを見出した。
本実施形態に係るフィルターは、基材1と基材1内に設けられた触媒物質2とを含み、基材1が、気体の流入側端部2と流出側端部3とを有し気体の流路となる複数のセル4と、これらセル4を画定する多孔質の複数の隔壁5とを備え、少なくとも一部のセル4の端部が目封じされ、隔壁の孔(図示せず)内における触媒物質(図示せず)の空孔占有率が10%以下であることを特徴とする。
また、これらの貴金属は、一種または二種以上の混合物として用いることができ、本願発明の好ましい態様によれば、白金とパラジウムの混同物、白金とパラジウムと金の混合物がより好ましい。
本実施形態に係るフィルターにおいては、画像処理で占有面積を求める際に、画像を2値化し、人為的な誤差を防ぐために自動モード等で計算をする。
触媒物質の塗布範囲を、隔壁の長さ方向の全長に対して、10%から50%の範囲とすることで、特に高いNOx浄化性能を得ることができるといった効果を得ることができる。この場合、塗布範囲を気体の流入側端部からとして、気体の流出側には触媒物質を設けないことが好ましい。
圧損とPM捕集性能のバランスの上からより好ましくは、基材1の気孔率が45%から65%である。
より好ましくは、触媒物質による隔壁5の孔の空孔占有率が5%未満である。
DPF(ディーゼル・パーティキュレート・フィルター)基材(直径143.8mm、長さ152.4mm)に対して、平均粒子径(D50)が0.02μm、0.5μm、2.1μm又は4.5μmのアルミナ粒子を含むスラリーを、11g/Lでコートし、乾燥後に500℃で焼成して、触媒担持DPFを作成した。この触媒担持DPFについて、300kg/hの空気流通下での圧力損失(BP)を測定した。
平均粒子径0.02μmのアルミナ粒子を用いて、触媒量を11g/L、25g/L、45g/Lとした3種の触媒担持CSF(キャタライズド・スート・フィルター)を調製した。
それぞれの触媒担持CSFの細孔の充填率を画像処理による方法で求め、PM発生器にてPM捕集効率の測定を行った。その結果を図5に示す。図5の結果から、細孔充填率の増加に伴いPM捕集効率が低下することがわかる。
実施例2で調製した触媒担持CSFを用いて、圧力損失を測定した。その結果を図6に示す。図6の結果から、細孔充填率の増加に伴い圧力損失が増加することがわかる。PM燃焼の観点からは触媒が存在することが望ましいが、実施例2と3の結果から、フィルター基材の細孔充填率は低い方が好ましいことがわかる。
図7は、Pt/Pd比と燃焼温度との関係性を示すグラフである。図7のグラフの点は、それぞれPt/Pd=1/0、3/1、2/1、1/1を示している。図7の結果から、PFFをエミッションの低減に寄与させるためにはPdの割合が高いことが好ましく、PM燃焼に寄与させるためにはPtの割合が高いことが好ましいことがわかる。
Claims (9)
- 基材と基材内に設けられた触媒物質とを含み、
基材が、気体の流入側端部と流出側端部とを有し気体の流路となる複数のセルと、これらセルを画定する多孔質の複数の隔壁とを備え、少なくとも一部のセルの端部が目封じされ、
隔壁の孔内における触媒物質の空孔占有率が10%以下であるフィルター。 - 触媒物質が、隔壁の孔の平均細孔径D50の10分の1以下の平均粒子径D50を有する請求項1に記載のフィルター。
- 気体の流入側端部と流出側端部の触媒物質に含有される貴金属の濃度の比が10/90から90/10である請求項1又は2に記載のフィルター。
- 触媒物質が、気体の流入側端部から、隔壁の長さ方向の全長の10%から50%の範囲で含まれる請求項1から3のいずれか一項に記載のフィルター。
- 触媒物質として、PtとPdとを、1:1から10:1の割合で含む請求項1から4のいずれか一項に記載のフィルター。
- 酸素貯蔵材料、アルカリ金属およびペロブスカイト型材料からなる群より選択される少なくとも一種の材料を更に含む請求項1から5のいずれか一項に記載のフィルター。
- 気体の流入側端部と流出側端部のいずれか一方のみが部分的に目封じされている請求項1から6のいずれか一項に記載のフィルター。
- 基材の気孔率が40%から70%である請求項1から7のいずれか一項に記載のフィルター。
- 触媒物質の空孔占有率が5%未満である請求項1から8のいずれか一項に記載のフィルター。
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PCT/JP2016/050353 WO2017119101A1 (ja) | 2016-01-07 | 2016-01-07 | フィルター |
RU2018128585A RU2018128585A (ru) | 2016-01-07 | 2016-01-07 | Фильтр |
BR112018013815-0A BR112018013815A2 (ja) | 2016-01-07 | 2016-01-07 | Filter |
EP16883604.7A EP3400999B1 (en) | 2016-01-07 | 2016-01-07 | Filter |
CN201680081724.0A CN108697956A (zh) | 2016-01-07 | 2016-01-07 | 过滤器 |
US15/324,278 US10137412B2 (en) | 2016-01-07 | 2016-01-07 | Filter |
JP2017559989A JPWO2017119101A1 (ja) | 2016-01-07 | 2016-01-07 | フィルター |
DE102017100241.3A DE102017100241A1 (de) | 2016-01-07 | 2017-01-09 | Filter |
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