WO2015083590A1 - Catalyseur de purification de gaz d'échappement et procédé pour sa production - Google Patents

Catalyseur de purification de gaz d'échappement et procédé pour sa production Download PDF

Info

Publication number
WO2015083590A1
WO2015083590A1 PCT/JP2014/081205 JP2014081205W WO2015083590A1 WO 2015083590 A1 WO2015083590 A1 WO 2015083590A1 JP 2014081205 W JP2014081205 W JP 2014081205W WO 2015083590 A1 WO2015083590 A1 WO 2015083590A1
Authority
WO
WIPO (PCT)
Prior art keywords
catalyst
zirconium
barium
slurry
catalyst layer
Prior art date
Application number
PCT/JP2014/081205
Other languages
English (en)
Japanese (ja)
Inventor
明生 立見
勝 香川
和人 板谷
和剛 武田
Original Assignee
田中貴金属工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 田中貴金属工業株式会社 filed Critical 田中貴金属工業株式会社
Priority to CN201480066003.3A priority Critical patent/CN105792929B/zh
Publication of WO2015083590A1 publication Critical patent/WO2015083590A1/fr

Links

Images

Classifications

    • 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
    • F01N3/101—Three-way catalysts
    • 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
    • B01D53/9445—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
    • B01D53/945—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC] characterised by a specific catalyst
    • 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
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/63—Platinum group metals with rare earths or actinides
    • 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
    • B01J37/0234—Impregnation and coating simultaneously
    • 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
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/204—Alkaline earth metals
    • B01D2255/2042—Barium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/206—Rare earth metals
    • B01D2255/2061—Yttrium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/206—Rare earth metals
    • B01D2255/2063—Lanthanum
    • 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
    • B01D2255/40—Mixed oxides
    • B01D2255/407—Zr-Ce mixed oxides
    • 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
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • B01J35/19—
    • B01J35/391—
    • B01J35/40—
    • 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
    • B01J37/04—Mixing
    • 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
    • F01N2370/00—Selection of materials for exhaust purification
    • F01N2370/02—Selection of materials for exhaust purification used in catalytic reactors
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the present invention relates to an exhaust gas purification catalyst and a method for producing the same, and more particularly to a catalyst suitable as a three-way catalyst for purifying carbon monoxide, hydrocarbons and nitrogen oxides in exhaust gas.
  • a three-way catalyst is used that simultaneously purifies by oxidizing or reducing carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx), which are harmful substances contained in the exhaust gas.
  • an oxygen storage material such as a ceria-zirconia composite oxide is used in addition to a general metal oxide support such as alumina as a support for supporting a catalyst metal.
  • OSM oxygen storage material
  • Patent Document 1 describes an exhaust gas purification catalyst in which palladium is disposed in a first coating layer and platinum and rhodium are disposed in a second coating layer.
  • the catalyst in which a plurality of catalyst layers are formed in this way needs to be individually manufactured for each catalyst layer to be formed, such as preparation of the slurry, application to the support, and firing in preparation of the catalyst.
  • the number of manufacturing steps is increased, resulting in an expensive catalyst.
  • Patent Document 2 discloses that rhodium and palladium are used as catalyst metals and two types of ceria-zirconia composite oxidation as a support. The catalyst using the product is described. In such a catalyst, the catalyst metal alloying is suppressed by carrying different catalyst metals on the two types of carriers.
  • Patent Document 2 describes a method for supporting a catalytic metal using tetraethylammonium hydroxide (TEAH) as an alkaline solution.
  • TEAH tetraethylammonium hydroxide
  • TEAH TEAH is added to raise the pH. Rhodium is deposited.
  • the second type carrier is suspended in the slurry, and TEAH is added to the slurry that has become acidic again by adding a palladium salt to raise the pH again, thereby precipitating palladium.
  • the catalyst of Patent Document 2 does not have sufficient purification performance when put to practical use as an exhaust gas purification catalyst, and further improvement in catalytic activity is expected.
  • a catalyst in which a catalytic metal is deposited using an alkaline solution is difficult to have a high catalytic activity.
  • the present inventors can realize further improvement in catalyst performance by reliably supporting the catalyst metal while suppressing the rearrangement of the catalyst metal and precipitation as a hydroxide.
  • the exhaust gas purifying catalyst of the present invention was obtained.
  • the obtained catalyst was analyzed in detail. When the ratio of zirconium concentration to cerium concentration (zirconium concentration / cerium concentration) was high on the catalyst layer surface, the supported state of the catalyst metal on the support was certain. As a result, the inventors have conceived the exhaust gas purifying catalyst of the present invention.
  • the present invention is an exhaust gas purification catalyst in which a single catalyst layer is formed on a support, the catalyst layer comprising an inorganic oxide composed of at least one of alumina, ceria, and zirconia, and ceria- the carrier comprising a mixture of a zirconia composite oxide, which palladium and rhodium are supported, furthermore, the ratio of the zirconium concentration in the surface of the catalyst layer (S Zr) and cerium concentration (S Ce) (S Zr / S Ce ) is 1.05 to 6.0 with respect to the ratio (C Zr / C Ce ) of zirconium concentration (C Zr ) to cerium concentration (C Ce ) at the interface of the catalyst layer with the support.
  • the present invention relates to an exhaust gas purification catalyst.
  • the exhaust gas purifying catalyst of the present invention is one in which two layers of palladium and rhodium are supported on a carrier as a catalyst metal while the catalyst layer is a single layer.
  • the catalyst of the present invention is characterized in that the ratio of zirconium concentration to cerium concentration (zirconium concentration / cerium concentration) is higher near the surface of the catalyst layer than near the interface with the support.
  • Such a catalyst of the present invention has a high degree of dispersion of the catalyst metal and high catalyst performance (particularly, CO oxidation and NOx reduction ability).
  • the zirconium / cerium concentration (S Zr / S Ce , C Zr / C Ce ) is the value at the surface of the catalyst layer (S Zr / S Ce ) and the value at the interface with the support of the catalyst layer (C Zr / C Ce). ) ((S Zr / S Ce ) / (C Zr / C Ce )), 1.05 to 6.0, preferably 1.1 to 5.0, and preferably 1.1 to 3.5 Particularly preferred. If it is less than 1.05, the durability of the catalyst metal tends to be insufficient, and if it exceeds 6.0, the degree of dispersion of the catalyst metal tends to be low.
  • Zirconium / cerium concentration ratio (S Zr / S Ce ) on the surface of the catalyst layer is measured from the outermost surface of the catalyst layer to the support side at the measurement position in the depth direction of the catalyst layer from the catalyst layer surface to the interface with the support.
  • the analysis result at a measurement position having a depth of 5 to 10 ⁇ m can be applied.
  • the zirconium / cerium concentration (C Zr / C Ce ) at the interface with the support of the catalyst layer the analysis result at a measurement position having a depth of 5 to 10 ⁇ m on the surface side from the interface with the support can be applied.
  • the above zirconium concentration / cerium concentration (S Zr / S Ce , C Zr / C Ce ) can be measured by an electron beam microanalyzer (EPMA).
  • CZ ceria-zirconia composite oxide
  • an inorganic oxide such as alumina.
  • CZ is preferably such that the ratio of zirconium oxide to cerium oxide (zirconia / ceria) is 95/5 to 5/95 in terms of mass ratio.
  • oxides of rare earth elements such as yttrium, lanthanum, and praseodymium, and oxides of alkaline earth elements such as magnesium and calcium may be included.
  • the content of CZ is preferably 20 to 80% by mass with respect to the total mass of the catalyst.
  • the inorganic oxide one or more of alumina, ceria, zirconia and the like can be used, and alumina is particularly preferable.
  • alumina ⁇ -alumina is suitable, and it may be doped with rare earth elements such as yttrium, lanthanum, and praseodymium.
  • the content of the inorganic oxide is preferably 20 to 80% by mass with respect to the total mass of the catalyst layer.
  • Catalyst metals include both palladium and rhodium.
  • the amount of the catalyst metal supported is preferably 0.1 to 2.5% by mass relative to the support. If it is less than 0.1% by mass, sufficient catalyst performance is difficult to obtain, and if it exceeds 2.5% by mass, it is not economical and the catalyst metal tends to aggregate.
  • the catalyst layer preferably contains a barium compound in addition to the carrier and the catalyst metal.
  • a catalyst containing barium is likely to have a higher CO oxidizing power and NOx reducing power.
  • the barium compound any of barium sulfate, barium carbonate, and barium oxide is preferable. These barium salts are present as barium sulfate or barium carbonate in unused exhaust gas purification catalysts, and are often present in the catalyst layer as barium carbonate or barium oxide after the catalyst is used.
  • the exhaust gas purification catalyst of the present invention is provided with the catalyst layer described above on a support made of a structural body such as a ceramic honeycomb, a metal honeycomb, or a nonwoven fabric.
  • a palladium salt and a rhodium salt are added to a carrier slurry in which a ceria-zirconia composite oxide and an inorganic oxide are suspended to form a catalyst layer precursor.
  • a catalyst layer precursor a ceria-zirconia composite oxide and an inorganic oxide.
  • a manufacturing method in which a zirconium compound is contained in the carrier slurry can be applied.
  • the catalyst metal is surely supported in a supported state because the catalyst metal can be prevented from precipitating as a hydroxide as in the case where the catalyst metal is supported using an alkaline solution, and the catalyst metal is supported on the carrier as ions. It is thought to be for this purpose. Further, as in the case where the catalyst metal is precipitated as a hydroxide, the catalyst metal is hardly coarsened due to the bond between the hydroxides.
  • the carrier, ceria-zirconia composite oxide and inorganic oxide are suspended in water to prepare a carrier slurry.
  • the amount of each carrier added is preferably 20 to 70% by mass of the inorganic oxide and 20 to 70% by mass of the ceria-zirconia composite oxide with respect to the entire catalyst layer obtained.
  • the particle size distribution is preferably 0.1 to 20 ⁇ m.
  • the ceria-zirconia composite oxide and the inorganic oxide those having the same types and particle sizes as described above can be applied as the exhaust gas purification catalyst.
  • the carrier slurry it is preferable to make a slurry by mixing an insoluble barium compound as an additive together with the ceria-zirconia composite oxide and the inorganic oxide.
  • an insoluble barium compound in addition to the zirconium compound, a catalyst with higher catalytic performance can be easily obtained.
  • the insoluble barium compound may be added at any time before or after the preparation of the catalyst slurry as long as it is before the addition of the catalyst metal, but is added together with the ceria-zirconia composite oxide or inorganic oxide as the support at the time of preparation of the support slurry. It is preferable to do. Since the insoluble barium compound is in a particulate form, it is easy to adjust a mixed slurry having a uniform particle size distribution by pulverizing and mixing together with a particulate carrier to form a slurry.
  • an insoluble barium compound when applied as in the present invention, the particle shape can be maintained in the carrier slurry, so that the oxygen absorption / release capability is not inhibited on the surface of the ceria-zirconia composite oxide, and the barium is not contained in the catalyst layer. It is also possible to disperse the components uniformly.
  • an insoluble barium compound the thing similar to the above-mentioned particle diameter as a structure of an exhaust gas purification catalyst is applicable.
  • a palladium salt and a rhodium salt are added as catalyst metal salts to the carrier slurry to prepare a mixed slurry that becomes a precursor of the catalyst layer.
  • a general water-soluble compound such as nitrate and acetate can be used, and nitrate is preferred.
  • the amount of each catalyst metal salt added is preferably 0.1 to 2.5% by mass of palladium and 0.1 to 0.5% by mass of rhodium with respect to the support.
  • the catalyst metal in the production method of the present invention, by adding a zirconium salt, the catalyst metal can be immobilized on the support without using an alkaline solution as in the production method described in Patent Document 2, so that the catalyst metal is water. Precipitation as an oxide can be suppressed.
  • the pH of the mixed slurry after the addition of the catalyst metal salt is a value that varies depending on the amount of addition of the catalyst metal salt, but in the implementation conditions of the present invention, it is often within the range of about 2.5 to 6.0, It is particularly often about 3.0 to 5.0. According to the present invention, after the addition of the catalyst metal salt, the catalyst metal can be reliably deposited on the support without adding an alkaline solution.
  • the catalyst metal may fall off in the step of drying and firing the mixed slurry to which the catalyst metal is added, but the catalyst metal deposited by the production method of the present invention is dried and fired. In such cases, the catalyst metal is unlikely to fall off.
  • the mixed slurry prepared above is preferably prepared such that the solid content of all catalyst components in the slurry is 20 to 50% by mass with respect to the mixed slurry.
  • the obtained mixed slurry is applied to a support to form a single catalyst precursor layer, and then fired to form a catalyst layer to produce an exhaust gas purification catalyst.
  • the firing temperature of the support is preferably 400 to 700 ° C.
  • the viscosity of the slurry may be adjusted using a regulator such as acetic acid or water. However, addition of an alkaline solution that tends to reduce the dispersibility of the catalyst metal is also avoided when adjusting the viscosity.
  • the support coated with the mixed slurry is preferably dried before firing. The drying temperature is preferably 90 to 200 ° C.
  • the exhaust gas purification catalyst of the present invention is particularly excellent in catalyst performance while utilizing the characteristics of a plurality of catalyst metals.
  • First embodiment 100 g of activated alumina (lanthanum-doped ⁇ -alumina) which is an inorganic oxide, 60 g of ceria-zirconia composite oxide (CeZrLaY, zirconia / ceria ratio 65/35), and barium acetate (purity 99% or more) 7.0 g was added to a mixed solution of 1.8 g of acetic acid and 0.17 L of pure water, and pulverized and mixed with an alumina media mill to prepare a carrier slurry.
  • activated alumina lanthanum-doped ⁇ -alumina
  • CaZrLaY ceria-zirconia composite oxide
  • barium acetate purity 99% or more
  • zirconium oxynitrate (purity 99.0% or more) or the like is added to and mixed with this carrier slurry, and further 8.3 g of palladium nitrate (Tanaka Kikinzoku Kogyo Co., Ltd.) and rhodium nitrate (Tanaka Kikinzoku Kogyo). 1.7 g was added and mixed to prepare a mixed slurry.
  • the slurry had a pH of about 4.4.
  • Acetic acid and water were added to the slurry to adjust the viscosity, and the slurry was applied to a support (monolith manufactured by cordierite, volume 1 L, cell number 600 cpsi, wall thickness 4.3 mil).
  • a catalyst to which no barium salt or zirconium salt was added (Test No. 1-1), a catalyst in which the amount of zirconium salt added was changed (Test Nos. 1-3 to 1-5), Catalysts (test Nos. 1-6 to 1-8) using zirconium acetate, zirconium hydroxide, and zirconia sol instead of zirconium oxynitrate were also produced in the same manner as described above. Further, a catalyst (Test No. 1-9) containing zirconium oxynitrate and using barium sulfate as the barium salt instead of barium acetate was also produced.
  • the zirconium / cerium concentration ratio in the catalyst layer was analyzed, and the supported state of the catalyst metal on the carrier was also confirmed. Moreover, the exhaust gas purification ability of CO, NO, and HC was evaluated as catalyst performance.
  • the zirconium / cerium concentration ratio in the catalyst layer was analyzed using an electron beam microanalyzer (EPMA).
  • the electron beam irradiation conditions were an acceleration voltage of 20 kV and an irradiation current of 1.0 ⁇ 10 ⁇ 8 A, and the irradiation position of the electron beam on the catalyst layer was moved every 0.2 ⁇ m from the vicinity of the center of the support toward the surface of the catalyst layer. Line analysis was performed.
  • the average (X 2 ) of the zirconium / cerium concentration ratio was determined. In this test, the measurement position where the X-ray intensity of Zr was 10 or less was defined as the outermost surface of the catalyst layer.
  • the ratio of the obtained surface layer side zirconium / cerium ratio (X 1 ) and the support side zirconium / cerium ratio (X 2 ) was determined to obtain the zirconium concentration ratio (X 1 / X 2 ) of the catalyst layer surface layer side and the support side. . No.
  • the EPMA measurement results for 1-5 are shown in FIG.
  • the supported state of the catalyst metal on the support depending on the presence or absence of addition of Ba salt and Zr salt was confirmed.
  • Test No. In the steps of producing the respective catalysts 1-1, 1-2, and 1-9, the mixed slurry after addition of the catalyst metal salt was used. Specifically, the concentration of noble metals (Pd and Rh) contained in the supernatant of the supernatant obtained by centrifuging the mixed slurry after the addition of palladium nitrate and rhodium nitrate and filter filtration is determined by the high frequency inductively coupled plasma method ( ICP). From the noble metal concentration in the supernatant, the proportion of the noble metal added to the slurry fixed on the inorganic oxide support was determined.
  • ICP inductively coupled plasma method
  • the exhaust gas purification performance (T 50 ) of the catalysts 1-1 to 1-9 was evaluated.
  • a catalyst cored in a cylindrical shape from the support was used for performance evaluation.
  • the cored catalyst was subjected to deterioration treatment at 900 ° C. for 10 hours using an atmospheric furnace before performance evaluation.
  • reaction gas for performance evaluation simulates engine exhaust gas, as Rich gas, CO 2 10%, CO 0.77%, H 2 0.2%, C 3 H 8 100 ppm, C 3 H 6 300 ppm, NO 800 ppm, Using O 2 0.4% and H 2 O 10.0%, as Lean gas, CO 2 10%, CO 0.77%, H 2 0.2%, C 3 H 8 100 ppm, C 3 H 6 300 ppm , NO 800 ppm, O 2 0.4%, H 2 O 10.0%. Any of the atmospheric gas even balance was N 2.
  • the reaction gas supplied to the catalyst was a space velocity (SV) of 90,000 h ⁇ 1 and Rich / Lean was continuously switched every second.
  • the catalyst containing the zirconium salt (Test Nos. 1-3 to 1-9) had a low T 50 and a high catalytic activity in any purification performance of CO, NO, and HC. Further, when both barium and zirconia were contained (Test No. 1-9), T 50 was particularly low, and good catalytic activity was exhibited.
  • the catalyst to which the zirconium salt was added had a larger amount of catalytic metal immobilized on the carrier and the catalytic activity was better than the catalyst to which the zirconium salt was not added.
  • the catalyst to which both barium and zirconia were added most of the catalyst metal used was immobilized, and the catalytic activity was particularly high.
  • Second embodiment A catalyst was produced using barium sulfate having a particle size shown in Table 4 below. Other manufacturing conditions and performance evaluation were performed in the same manner as in the first embodiment.
  • Catalysts were produced using barium salts and zirconium salts shown in Table 5 below.
  • Test No. 3-1 after adding palladium nitrate and rhodium nitrate to the carrier slurry, TEAH was added as an alkaline solution to raise the pH to 7.0.
  • Test No. The catalysts 3-3 to 3-5 were subjected to a aging treatment at 950 ° C. for 10 hours after the production of the catalyst. Other catalyst production conditions were the same as in the first embodiment, and the catalyst was produced.
  • the unit dispersion and average particle size of the catalyst metal were measured by the CO pulse adsorption method. Specifically, the catalyst is held at 400 ° C. for 15 minutes in an oxygen atmosphere, then held at 400 ° C. for 15 minutes in a hydrogen atmosphere, and further cooled to 50 ° C. in a helium atmosphere. Was measured. By this measurement, the number of atoms of the catalyst metal exposed on the catalyst layer surface can be measured.
  • the unit dispersity indicates the ratio (%) of the amount of the catalyst metal supported on the carrier that is exposed on the surface of the catalyst layer, and was calculated from the CO adsorption amount.
  • the average particle diameter was calculated from the surface area of the catalyst metal calculated from the CO adsorption amount, assuming that the shape of the catalyst metal was spherical.
  • the catalyst added with the zirconium salt and not using the alkaline solution was adjusted to pH in the alkaline solution.
  • the catalyst metal unit dispersion was higher and the average particle size was smaller than that of the catalyst with adjusted (Test No. 3-1).
  • the catalyst metal was increased in particle size because the catalyst metal was precipitated as a hydroxide.
  • the exhaust gas purification catalyst of the present invention is particularly suitable as a three-way catalyst.

Abstract

La présente invention vise à produire un catalyseur de purification de gaz d'échappement contenant une pluralité de métaux catalyseurs, la couche de catalyseur associée comprenant une couche unique, le degré de dispersion des métaux catalyseurs étant élevé et les performances de catalyseur associées étant également élevées. La présente invention vise également à procurer un procédé pour produire ce catalyseur, lequel peut être définitivement supporté, sans l'utilisation d'une solution alcaline. À cet effet, la présente invention porte sur un catalyseur de purification de gaz d'échappement, lequel catalyseur est obtenu par la formation d'une couche de catalyseur unique sur un corps de support, et dans lequel : la couche de catalyseur est obtenue par le fait de porter du palladium et du rhodium sur un porteur obtenu par mélange d'un oxyde minéral tel que de l'alumine et d'un oxyde composite d'oxyde de cérium et d'oxyde de zirconium l'un avec l'autre ; et le rapport (SZr/SCe) de la concentration de zirconium à la concentration de cérium dans la surface de la couche de catalyseur étant de 1,05 à 6,0 fois le rapport (CZr/CCe) de la concentration de zirconium à la concentration de cérium au niveau de l'interface entre la couche de catalyseur et le corps de support.
PCT/JP2014/081205 2013-12-02 2014-11-26 Catalyseur de purification de gaz d'échappement et procédé pour sa production WO2015083590A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201480066003.3A CN105792929B (zh) 2013-12-02 2014-11-26 废气净化催化剂及其制造方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2013249137A JP5777690B2 (ja) 2013-12-02 2013-12-02 排ガス浄化触媒及びその製造方法
JP2013-249137 2013-12-02

Publications (1)

Publication Number Publication Date
WO2015083590A1 true WO2015083590A1 (fr) 2015-06-11

Family

ID=53273353

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2014/081205 WO2015083590A1 (fr) 2013-12-02 2014-11-26 Catalyseur de purification de gaz d'échappement et procédé pour sa production

Country Status (3)

Country Link
JP (1) JP5777690B2 (fr)
CN (1) CN105792929B (fr)
WO (1) WO2015083590A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017130623A1 (fr) * 2016-01-28 2017-08-03 株式会社キャタラー OXYDE COMPOSITE À BASE DE Zr SUPPORTANT Pd
CN110494215A (zh) * 2017-04-11 2019-11-22 株式会社科特拉 排气净化用催化剂

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111405941B (zh) * 2017-12-28 2022-09-27 优美科触媒日本有限公司 制氢用催化剂及使用其的废气净化用催化剂
CN108993560A (zh) * 2018-07-25 2018-12-14 昆明贵研催化剂有限责任公司 一种耐水耐高温甲烷氧化催化剂及其制备方法
CN112675845B (zh) * 2020-12-28 2022-03-29 四川大学 一种用于天然气车尾气净化的Pd-Rh单涂层催化剂及其制备方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6458347A (en) * 1987-08-28 1989-03-06 Engelhard Nippon Catalyst of superior heat resistance for purifying internal combustion engine exhaust gas and its preparation
WO1990014888A1 (fr) * 1989-06-09 1990-12-13 N.E. Chemcat Corporation Catalyseur purificateur de gaz d'echappement a excellente resistance thermique et sa methode de production
JPH09131530A (ja) * 1995-11-09 1997-05-20 Ict:Kk 内燃機関排ガス浄化用触媒
JPH11151439A (ja) * 1997-11-20 1999-06-08 Daihatsu Motor Co Ltd 排気ガス浄化用触媒
JP2003526493A (ja) * 1998-05-01 2003-09-09 エンゲルハード・コーポレーシヨン 電気アーク噴霧法により噴霧された基質を有する触媒部材およびその製造法
JP2006263583A (ja) * 2005-03-24 2006-10-05 Mazda Motor Corp 排気ガス浄化用触媒
WO2009116468A1 (fr) * 2008-03-19 2009-09-24 株式会社アイシーティー Catalyseur pour l'épuration d'un gaz d'échappement de moteur à combustion interne et procédé d'épuration de gaz d'échappement à l'aide dudit catalyseur

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19847008A1 (de) * 1998-10-13 2000-04-20 Degussa Stickoxid-Speicherkatalysator
CN1854474A (zh) * 2005-04-27 2006-11-01 马自达汽车股份有限公司 柴油汽车尾气微粒子过滤器
JP4841539B2 (ja) * 2007-04-12 2011-12-21 日産自動車株式会社 排気ガス浄化用触媒及びその製造方法
US8038951B2 (en) * 2007-08-09 2011-10-18 Basf Corporation Catalyst compositions
JP5086964B2 (ja) * 2008-10-08 2012-11-28 三井金属鉱業株式会社 排気ガス浄化用触媒の製造方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6458347A (en) * 1987-08-28 1989-03-06 Engelhard Nippon Catalyst of superior heat resistance for purifying internal combustion engine exhaust gas and its preparation
WO1990014888A1 (fr) * 1989-06-09 1990-12-13 N.E. Chemcat Corporation Catalyseur purificateur de gaz d'echappement a excellente resistance thermique et sa methode de production
JPH09131530A (ja) * 1995-11-09 1997-05-20 Ict:Kk 内燃機関排ガス浄化用触媒
JPH11151439A (ja) * 1997-11-20 1999-06-08 Daihatsu Motor Co Ltd 排気ガス浄化用触媒
JP2003526493A (ja) * 1998-05-01 2003-09-09 エンゲルハード・コーポレーシヨン 電気アーク噴霧法により噴霧された基質を有する触媒部材およびその製造法
JP2006263583A (ja) * 2005-03-24 2006-10-05 Mazda Motor Corp 排気ガス浄化用触媒
WO2009116468A1 (fr) * 2008-03-19 2009-09-24 株式会社アイシーティー Catalyseur pour l'épuration d'un gaz d'échappement de moteur à combustion interne et procédé d'épuration de gaz d'échappement à l'aide dudit catalyseur

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017130623A1 (fr) * 2016-01-28 2017-08-03 株式会社キャタラー OXYDE COMPOSITE À BASE DE Zr SUPPORTANT Pd
JP6246424B1 (ja) * 2016-01-28 2017-12-13 株式会社キャタラー Ｐｄ担持Ｚｒ系複合酸化物
CN108602049A (zh) * 2016-01-28 2018-09-28 株式会社科特拉 担载Pd的Zr系复合氧化物
US11084022B2 (en) 2016-01-28 2021-08-10 Cataler Corporation Pd-supporting Zr-based composite oxide
CN108602049B (zh) * 2016-01-28 2021-09-03 株式会社科特拉 担载Pd的Zr系复合氧化物
CN110494215A (zh) * 2017-04-11 2019-11-22 株式会社科特拉 排气净化用催化剂
US11504700B2 (en) 2017-04-11 2022-11-22 Cataler Corporation Exhaust gas purification catalyst

Also Published As

Publication number Publication date
JP2015104715A (ja) 2015-06-08
CN105792929A (zh) 2016-07-20
JP5777690B2 (ja) 2015-09-09
CN105792929B (zh) 2018-06-26

Similar Documents

Publication Publication Date Title
JP4950365B2 (ja) 混合相セラミック酸化物三元合金触媒製剤及びその触媒製造方法
EP2452750A1 (fr) Catalyseur de purification de gaz d échappement et procédé de production associé
EP1900427A1 (fr) Système de catalyseur pour dispositifs de purification de gaz d'échappement de véhicule, dispositif de gaz d'échappement l'utilisant, et procédé de purification de gaz d'échappement
WO2015083590A1 (fr) Catalyseur de purification de gaz d'échappement et procédé pour sa production
JP2005262201A (ja) 排ガス浄化用触媒およびその製造方法
CN111065456B (zh) 废气净化催化剂
WO2014080695A1 (fr) Particules d'oxyde complexe et catalyseur pour la purification de gaz d'échappement l'utilisant
CN113042045B (zh) 排气净化用催化剂
JP2022061979A (ja) 排ガス用浄化触媒組成物、及び自動車用排ガス浄化触媒
JP4831753B2 (ja) 排ガス浄化用触媒
JPS63205141A (ja) 排ガス浄化用触媒
CN113042047A (zh) 排气净化用催化剂
WO2019167515A1 (fr) Catalyseur à trois voies pour purification de gaz d'échappement, procédé de fabrication associé et catalyseur monolithique pour purification de gaz d'échappement
CN106457226B (zh) 废气净化用催化剂
JP6532825B2 (ja) 排ガス浄化用触媒
JP4979087B2 (ja) 複合酸化物粉末、その製造方法及び製造装置、並びに排ガス浄化用触媒
JP2013180283A (ja) 酸化触媒及びそれを用いた排ガス浄化方法
JP6050703B2 (ja) 排ガス浄化用触媒
JP5030573B2 (ja) 複合酸化物粉末及びその製造方法
JP7329060B2 (ja) 排気ガス浄化用触媒、排気ガスの浄化方法、及び排気ガス浄化用触媒の製造方法
JP4775953B2 (ja) 排ガス浄化用触媒及びその再生方法
JP4836187B2 (ja) 排ガス浄化用触媒、並びにその製造方法及びその再生方法
JP6096818B2 (ja) 排ガス浄化触媒、その製造方法、及び、それを用いた排ガス浄化方法
RU2790008C2 (ru) Катализатор для очистки выхлопного газа
JP4836188B2 (ja) 排ガス浄化用触媒、並びにその製造方法及びその再生方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14868109

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14868109

Country of ref document: EP

Kind code of ref document: A1