US5219545A
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Catalyst and method for catalytically decomposing nitrogen oxides
Assignee: Tosoh Corp
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Filing: 1991-03-08
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Granted: 1993-06-15
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Expires: 2011-03-08
Abstract
Abstract A catalyst and a method for catalytically decomposing nitrogen oxides, wherein the catalyst comprises a zeolite having a mole ratio of SiO2/Al2O3 of at least 20, and containing (i) copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium and barium ions, (c) yttrium ions, or (a) silver ions.
Inventors
- 👤 Shuichi Kagawa
- 👤 Yasutake Teraoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:57
CPC Classifications
B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/064; B01J29/072; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01D2255/00; B01D2255/10; B01D2255/104; B01D2255/20; B01D2255/204; B01D2255/2042; B01D2255/2045; B01D2255/206; B01D2255/2061; B01D2255/207; B01D2255/20761; B01D2255/50
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
131 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per Al in the zeolite.
Claim 2
Independent Claim
131 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per Al in the zeolite.
Claim 3
Dependent Claim
42 words
A method as claimed in claim 1, wherein said catalyst comprises a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) copper ions and (ii) transition metal ions other than copper ions.
Claim 4
Dependent Claim
49 words
A method as claimed in claim 1, wherein said catalyst comprises a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) copper ions and (ii) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions.
Claim 5
Dependent Claim
36 words
A method as claimed in claim 1, wherein said catalyst comprises a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) copper ions and (ii) yttrium.
Claim 6
Dependent Claim
37 words
A method as claimed in claim 1, wherein said catalyst comprises a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) copper ions and (ii) silver ions.
Claim 7
Independent Claim
136 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides in the absence of ammonia, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per Al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per al in the zeolite.
Claim 8
Independent Claim
136 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides in the absence of ammonia, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per Al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per al in the zeolite.
Claim 9
Independent Claim
137 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides in the absence of a hydrocarbon, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per Al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per Al in the zeolite.
Claim 10
Independent Claim
137 words
A method of removing nitrogen oxides from a gas containing the same by catalytically decomposing the nitrogen oxide, which comprises bringing a catalyst into contact with the gas containing nitrogen oxides in the absence of a hydrocarbon, said catalyst comprising a zeolite having a mole ratio of SiO 2 /Al 2 O 3 of at least 20 and containing (i) 0.01 to 1.5, in terms of the atomic ratio of Cu per Al in the zeolite of copper ions and (ii) (a) transition metal ions other than copper ions, (b) at least one alkaline earth metal ion selected from calcium, strontium, and barium ions, (c) yttrium ions, or (d) silver ions, the amount of the metal ions (ii) being at least 0.01 in terms of the atomic ratio of the metal ions per Al in the zeolite.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-06-14 | 1996-12-14 | 1997-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-14 | 2000-12-14 | 2001-06-15 | $3760.00 | Window Closed / Lapsed |
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