US20020033015A1 - Process for denitrification of exhaust gasses, particularly for lean operated internal combustion engines - Google Patents
Process for denitrification of exhaust gasses, particularly for lean operated internal combustion engines Download PDFInfo
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- US20020033015A1 US20020033015A1 US09/912,004 US91200401A US2002033015A1 US 20020033015 A1 US20020033015 A1 US 20020033015A1 US 91200401 A US91200401 A US 91200401A US 2002033015 A1 US2002033015 A1 US 2002033015A1
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- porous carrier
- process according
- lean
- internal combustion
- nitrogen oxide
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- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 13
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims abstract description 57
- 239000000126 substance Substances 0.000 claims abstract description 21
- 239000010948 rhodium Substances 0.000 claims abstract description 14
- 239000000203 mixture Substances 0.000 claims abstract description 11
- 239000007789 gas Substances 0.000 claims abstract description 10
- 239000007787 solid Substances 0.000 claims abstract description 9
- 229910052703 rhodium Inorganic materials 0.000 claims abstract description 7
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 5
- 150000001340 alkali metals Chemical class 0.000 claims abstract description 5
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims abstract description 5
- 150000001875 compounds Chemical class 0.000 claims abstract description 5
- 239000000446 fuel Substances 0.000 claims abstract description 5
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 5
- 150000002910 rare earth metals Chemical class 0.000 claims abstract description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 3
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910021536 Zeolite Inorganic materials 0.000 claims abstract description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims abstract description 3
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910052814 silicon oxide Inorganic materials 0.000 claims abstract description 3
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000010457 zeolite Substances 0.000 claims abstract description 3
- 229910001928 zirconium oxide Inorganic materials 0.000 claims abstract description 3
- 229910000510 noble metal Inorganic materials 0.000 claims description 16
- 229910052697 platinum Inorganic materials 0.000 claims description 6
- 229910052763 palladium Inorganic materials 0.000 claims description 4
- 239000000969 carrier Substances 0.000 claims description 2
- 239000008188 pellet Substances 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- 230000003197 catalytic effect Effects 0.000 description 21
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 17
- 238000003860 storage Methods 0.000 description 14
- 238000006243 chemical reaction Methods 0.000 description 9
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 8
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 7
- 239000012876 carrier material Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 5
- 239000012495 reaction gas Substances 0.000 description 3
- 239000011232 storage material Substances 0.000 description 3
- QQONPFPTGQHPMA-UHFFFAOYSA-N Propene Chemical compound CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012432 intermediate storage Methods 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
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- PMTRSEDNJGMXLN-UHFFFAOYSA-N titanium zirconium Chemical compound [Ti].[Zr] PMTRSEDNJGMXLN-UHFFFAOYSA-N 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
- 239000011787 zinc oxide Substances 0.000 description 1
- 229910052845 zircon Inorganic materials 0.000 description 1
Images
Classifications
-
- 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
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
- B01J21/066—Zirconium or hafnium; Oxides or hydroxides thereof
-
- 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
- B01D53/9404—Removing only nitrogen compounds
- B01D53/9409—Nitrogen oxides
- B01D53/9413—Processes characterised by a specific catalyst
- B01D53/9422—Processes characterised by a specific catalyst for removing nitrogen oxides by NOx storage or reduction by cyclic switching between lean and rich exhaust gases (LNT, NSC, NSR)
-
- 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
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
-
- 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
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/46—Ruthenium, rhodium, osmium or iridium
- B01J23/464—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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/207—Transition metals
- B01D2255/20715—Zirconium
-
- 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
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
-
- 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
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/064—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof containing iron group metals, noble metals or copper
- B01J29/068—Noble metals
Definitions
- Both noble metals are provided as atomic mixtures upon the same porous carrier substance, which for its part is applied upon a geometric carrier.
- the NOx input concentration in this experiment corresponded to 280 ppm.
- the NOx concentration is shown in ppm, and on the right ordinate the ⁇ -signal is shown.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Combustion & Propulsion (AREA)
- Biomedical Technology (AREA)
- Environmental & Geological Engineering (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Catalysts (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
The invention is concerned with a process for denitrification of exhaust gasses of primarily lean operated internal combustion engines, including the following process steps:
placing in the exhaust gas stream of the internal combustion engine a nitrogen oxide storing and catalytically effective solid which is free of alkali earth metals, alkali metals and rare earth, comprising
(a) a porous carrier substance and
(b) rhodium, which is provided on the porous carrier substance,
storing the nitrogen oxide during the lean motor operating phase with an air/fuel ratio λ>1,
releasing and catalytically converting the nitrogen oxide during the rich motor operating phase with a air/fuel ratio X>1,
thereby characterized, that the porous carrier substance is comprised of at least 50 wt. % zirconium oxide, titanium oxide, silicon oxide or a zeolite, or a mixture of two or more of these compounds.
Description
- The invention concerns a process for denitrification of primarily lean operated internal combustion engines according to the precharacterizing portion of Patent claim 1.
-
EP 0 890 389 A1 discloses an NOx storage catalytic converter for cleansing the exhaust gasses of vehicle exhaust gas systems. The disclosed storage catalytic converter is comprised of two material components, wherein the one material component serves for intermediate storage of nitrogen oxide during lean operation of the vehicle internal combustion engine and the other material component is a catalytic material with three-way characteristics in which, during short term rich exhaust gas operation, stored nitrogen oxide is released and converted to molecular nitrogen (N2) - The required relationship between the lean operating phase and the rich operating phase in the combustion control of the vehicle internal combustion engine is determined by various parameters such as the NOx storage capacity of the material, the amount of NOx arriving, the exhaust gas temperature and, in the case of sulfur-containing exhaust gas, by the sulfur content. In order to achieve a low fuel consumption, it is desired to operate the vehicle internal combustion engine as long as possible with lean operating phases and as briefly as possible with rich operating phases. The NOx storage catalytic converter thus operates discontinuously, since the combustion control of the exhaust gas must be switched alternatingly from lean to rich.
-
EP 0 707 882 A1 discloses an NOx storage catalytic converter with an aluminum oxide containing carrier, upon which a Ti—Zr mixed oxide is applied. On the aluminum oxide containing carrier material there is further provided, for the collection and storage of nitrogen oxide, a compound selected from the group of elements of the alkali metals, alkali earth metals and rare earth. The aluminum oxide containing carrier material is further doped with a noble metal, for example palladium (Pd), platinum (Pt) or rhodium (Rh). - Alternative published embodiments of the known NOx storage catalytic converter exhibit a carrier material of a mixed oxide of the elements titanium (Ti), zircon (Zi) and yttrium (Y). The employed alkali metals, alkali earth metals or rare earth for storage of nitrogen oxide have the disadvantages of a low temperature stability as well as a low So 2-tolerance.
-
EP 0 927 571 A2 discloses a further NOx storage catalytic converter which is free of alkali metals, alkali earth metals and rare earth, with a carrier material comprising at least 50 wt. % aluminum oxide, which is doped with platinum and optionally with palladium, rhodium or other compounds. The disclosed aluminum oxide containing NOx storage catalyst (Pt/Al2O3 catalytic converter) absorbs nitrogen oxide from the exhaust gas in the lean motor operating phase and releases the nitrogen oxide during the rich motor operating phase with simultaneous conversion on platinum. - In the disclosed NOx storage catalytic converter the relationship of the lean motor operating phase to the rich motor operating phase was found to be problematic. It is only in a lean-rich cycle with respectively equal durations of a lean and rich motor operating phases (for example 60 seconds each) that, at a temperature of 350° C., a maximum NOx conversion of approximately 65% could be achieved. With shorter duration of the rich motor operating phase in comparison to the lean motor operating phase, a lower NOx conversion is achieved.
- It is the task of the invention to provide a process for denitrification of exhaust gasses from primarily lean operated internal combustion engines, which process achieves a good effectiveness even in the case of very short rich motor operating phases.
- The solution to the task is set forth in Patent claim 1. Further advantageous embodiments of the inventive process are set forth in the further claims.
- In the inventive process the porous carrier substance is comprised of at least 50 wt. % zirconium oxide, titanium oxide, silicon oxide or a zeolite, or a mixture of two or more of these compounds.
- The BET-surface of the above-listed carrier substances is preferably between 10 and 500 m 2/g. The rhodium concentration upon the listed carrier materials is preferably 0.1 to 2 wt. %, but can however be appropriately increased or reduced for targeted changes of the solids characteristics.
- For improvement of the nitrogen oxide storage and catalytic characteristics of the process it is possible to supplementally apply one or more noble metals, for example platinum, iridium or palladium upon the porous carrier substance. Thereby the activity of the material may be significantly increased.
- In an advantageous embodiment of the inventive process the nitrogen oxide storing and catalytically effective solid can, commensurate with the intended use, be employed in various forms such as, for example, pellets or extradites. The solid employed in the inventive process can however also be applied upon a geometric or shaped carrier made, for example, of metal or ceramic.
- The two noble metals applied upon the porous carrier substance (rhodium+supplemental noble metal) can be used together in accordance with the invention in the following manner:
- Micro-mixture
- Both noble metals are provided as atomic mixtures upon the same porous carrier substance, which for its part is applied upon a geometric carrier.
- Macro-mixture
- Both noble metal components are individually provided on respective separate porous carrier materials, wherein the carrier materials could be the same or different type. The respective noble metal doped carrier substances are applied as a powder mixture onto a geometric carrier.
- Layer Arrangement
- Noble metal components are provided, separately, in layers upon the porous carrier substances, which porous carrier substances are then provided upon a geometric carrier.
- Structured Arrangement
- Both noble metal components are provided respectively individually upon porous carrier substances, which are respectively, separately from each other, applied upon different geometric carriers, for example in serial arrangement.
- The inventive process is particularly suitable for employment in internal combustion vehicle motors, and in particular diesel motors, stoichiometrically and lean operated Otto motors, as well as gas motors.
- The invention will be described in greater detail below on the basis of the experimental results with reference to the figures. There is shown:
- FIG. 1 the temperature-dependent NOx conversion of an inventive Pt/Rh/ZrO 2-solid in λ-alternating operation,
- FIG. 2 the NOx concentration over time using the inventive Pt/Rh/ZrO 2-solid at T=280° C. in λ-alternating operation.
- During the experiments a lean operating phase of 90 seconds was alternated with a rich operating phase of 4 seconds. The reaction-gas had the following compositions in the lean and rich operating conditions:
Lean (λ = 2.4) Rich (λ = 0.7) NO 280 Vol.-ppm 280 Vol.-ppm O2 12.5 Vol.-% 0 Vol.-% CO 0.25 Vol.-% 9.3 Vol.-% H2 1500 Vol.-ppm 2.6 Vol.-% Propene 75 Vol.-ppm 2700 Vol.- ppm CO 2 10 Vol.-% 10 Vol.-% H2O 10 Vol.-% 10 Vol.-% N2 Rest Rest - The space velocity in the operating phases corresponded to 20000 1/h.
- FIG. 1 shows NOx conversion of the reaction gas for a catalytic converter operated in λ-alternating operation, using an exemplary Pt/Rh/ZrO 2 catalytic converter with 1.5 wt. % Pt and 0.5 wt. % Rh on microporous zinc oxide, as a function of the temperature (measured in advance of the catalytic converter). The catalytic converter was operated alternatingly 90 seconds lean and 4 seconds rich using synthetic exhaust gas. Simultaneously thereto a temperature program from 100° C. to 500° C. was carried out with a temperature ramp of 2° C./min. From the difference between the amount of nitrogen oxide supplied to the catalytic converter and the amount exiting from the catalytic converter, it was possible to determine an integral NOx conversion per lean-rich cycle carried out.
- With the present catalytic converter an NOx conversion maximum was observed in the temperature range between 160° C. and 500° C. This maximum was plotted at a temperature of approximately 280° C. and represented approximately 90w. Further, the present Pt/Rh/ZrO 2 catalytic converter achieved an NOx conversion of at least 50% over a broad temperature range (160° C.-370° C.)
- In FIG. 2 there is shown for the Pt/Rh/ZrO 2 catalytic converter described in FIG. 1, operated for exemplary purposes at T=280° C.—the temperature of the greatest NOx conversion—a plot over time of the NOx concentration downstream of the NOx storage material, measured in the λ-cycle operation of the reaction gas. The NOx input concentration in this experiment corresponded to 280 ppm. In FIG. 2 on the left ordinate the NOx concentration is shown in ppm, and on the right ordinate the λ-signal is shown. The upper curve shows the course of the λ-signal, the lower curve the corresponding time sequence of the NOx concentration. From this, according to the shown λ-signal prior to the NOx storage material, the lean operating phases (λ=2.4) and the rich operating phases (λ=0.7) can be designated.
- During the lean operation phase nitrogen oxide storage is determined wherein, on the basis of increasing loading of the nitrogen oxide storing solid, the NOx concentration downstream of the catalytic converter slowly increases. Therein the NOx concentration at the beginning of a lean operating phase (time point at which in the λ-cycle operating λ achieves the value 2.4), for example at approximately time 113.3 min., is approximately 10 ppm and increases towards the end of the lean operating phase after 90 seconds, corresponding to approximately time 114.8 min., up to approximately 80 ppm. The subsequent rich operating phase of approximately 4 s leads to a short time NOx concentration peak with a maximum at approximately 200 ppm, which lies clearly below the NOx intake concentration.
- Accordingly the nitrogen oxide bonded to the NOx storage material is released. A renewed alternation back to lean operation leads then to a lowering of the NOx concentration to approximately 10 ppm, and the cycle of the NOx storage and NOx release is repeated. Thereby an integral nitrogen oxide conversion of approximately 90% per cycle is achieved with the Pt/Rh/ZrO 2 catalytic converter.
Claims (8)
1. Process for denitrification of exhaust gasses of an internal combustion engine operated primarily in the lean phase including the following process steps:
placing in the exhaust gas stream of the internal combustion engine a nitrogen oxide storing and catalytically effective solid which is free of alkali earth metals, alkali metals and rare earth, comprising
(a) a porous carrier substance and
(b) rhodium, which is provided on the porous carrier substance,
storing nitrogen oxide during the lean motor operating phase with an air/fuel ratio λ>1,
releasing and catalytically converting the nitrogen oxide during the rich motor operating phase with an air/fuel ratio λ>1,
thereby characterized, that the porous carrier substance is comprised of at least 50 wt. % zirconium oxide, titanium oxide, silicon oxide or a zeolite or a mixture of two or more of these compounds.
2. Process according to claim 1 , thereby characterized, that a second noble metal, for example Pt, Pd, or Ir, or a mixture of noble metals, is provided upon the porous carrier substance.
3. Process according to one of the preceding claims, thereby characterized, that the solid is in the form of a pellet or extradite, or is provided upon a geometric carrier.
4. Process according to one of the preceding claims, thereby characterized, that the noble metals are provided as atomic mixture upon the porous carrier substance.
5. Process according to one of the preceding claims, thereby characterized, that the noble metals are respectively individually applied upon the same or different porous carrier substances.
6. Process according to claim 5 , thereby characterized, that the noble metals are respectively individually applied upon the same or different porous carrier substances to form a powder mixture.
7. Process according to claim 5 , thereby characterized, that the respective noble metals applied on identical or different porous carrier substances are provided upon a geometric carrier in layers.
8. Process according to claim 6 , thereby characterized, that the noble metals are respectively applied individually upon the same or different porous carrier substances are provided separately from each other upon different, for example serially arranged, geometric carriers.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE10036886A DE10036886B4 (en) | 2000-07-28 | 2000-07-28 | Method for denitrification of exhaust gases of predominantly lean-burn internal combustion engines |
| DE10036886.7-43 | 2000-07-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US20020033015A1 true US20020033015A1 (en) | 2002-03-21 |
Family
ID=7650583
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US09/912,004 Abandoned US20020033015A1 (en) | 2000-07-28 | 2001-07-24 | Process for denitrification of exhaust gasses, particularly for lean operated internal combustion engines |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US20020033015A1 (en) |
| EP (1) | EP1181971A3 (en) |
| DE (1) | DE10036886B4 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004022225A2 (en) * | 2002-09-09 | 2004-03-18 | Millennium Chemicals Thann Sas | Method for converting nitrogen oxides (nox) in exhaust gases and catalyst useful for it |
| US20080034740A1 (en) * | 2004-04-16 | 2008-02-14 | Wolfgang Strehlau | Process for the Removal of Harmful Substances From Exhaust Gases of Combustion Engines and Catalyst for Carrying Out Said Process |
| US20090255238A1 (en) * | 2005-11-10 | 2009-10-15 | Toyota Jidosha Kabushiki Kaisha | Exhaust Gas Purifying Apparatus and Exhaust Gas Purifying Method |
| CN113648831A (en) * | 2021-09-07 | 2021-11-16 | 安徽江淮汽车集团股份有限公司 | NSC denitrification method and device |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10340653B4 (en) * | 2003-09-03 | 2006-04-27 | Hte Ag The High Throughput Experimentation Company | Catalyst for the removal of pollutants from exhaust gases of lean-burn engines with ruthenium as active metal |
| CN104474857B (en) * | 2014-11-20 | 2016-07-06 | 浙江大学 | NO in the preposition oxidative absorption coal-fired flue-gas of bioactive moleculexAnd SO2Method and apparatus |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3498453B2 (en) * | 1995-11-27 | 2004-02-16 | 日産自動車株式会社 | Exhaust gas purification catalyst and method for producing the same |
| JPH09201531A (en) * | 1996-01-29 | 1997-08-05 | Toyota Central Res & Dev Lab Inc | Catalyst for purification of exhaust gas and method for purification of exhaust gas |
| EP0890389A1 (en) * | 1997-07-10 | 1999-01-13 | DORNIER GmbH | Solid material for adsorption and catalytic removal of nitrogen oxides |
| US6182443B1 (en) * | 1999-02-09 | 2001-02-06 | Ford Global Technologies, Inc. | Method for converting exhaust gases from a diesel engine using nitrogen oxide absorbent |
-
2000
- 2000-07-28 DE DE10036886A patent/DE10036886B4/en not_active Expired - Fee Related
-
2001
- 2001-07-03 EP EP01116084A patent/EP1181971A3/en not_active Withdrawn
- 2001-07-24 US US09/912,004 patent/US20020033015A1/en not_active Abandoned
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004022225A2 (en) * | 2002-09-09 | 2004-03-18 | Millennium Chemicals Thann Sas | Method for converting nitrogen oxides (nox) in exhaust gases and catalyst useful for it |
| WO2004022225A3 (en) * | 2002-09-09 | 2005-03-24 | Millennium Chemicals Thann Sas | Method for converting nitrogen oxides (nox) in exhaust gases and catalyst useful for it |
| US20080034740A1 (en) * | 2004-04-16 | 2008-02-14 | Wolfgang Strehlau | Process for the Removal of Harmful Substances From Exhaust Gases of Combustion Engines and Catalyst for Carrying Out Said Process |
| US8087235B2 (en) | 2004-04-16 | 2012-01-03 | Hte Aktiengesellschaft The High Throughput Experimentation Company | Process for the removal of harmful substances from exhaust gases of combustion engines and catalyst for carrying out said process |
| US20090255238A1 (en) * | 2005-11-10 | 2009-10-15 | Toyota Jidosha Kabushiki Kaisha | Exhaust Gas Purifying Apparatus and Exhaust Gas Purifying Method |
| CN113648831A (en) * | 2021-09-07 | 2021-11-16 | 安徽江淮汽车集团股份有限公司 | NSC denitrification method and device |
Also Published As
| Publication number | Publication date |
|---|---|
| DE10036886B4 (en) | 2006-01-05 |
| EP1181971A2 (en) | 2002-02-27 |
| EP1181971A3 (en) | 2002-03-27 |
| DE10036886A1 (en) | 2002-02-21 |
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