EP0161743A2
Expired / Lapsed
EP
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Vanadium oxide catalyst for nitrogen oxide reduction and process using the same
Assignee: BASF Catalysts LLC
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Filing: 1985-02-21
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Granted: —
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Expires: 2005-02-21
Abstract
Abstract A catalyst composition effective for selective catalytic reduction of nitrogen oxides with ammonia in a gas stream has an upstream section comprising a phosphorus getter comprised of a phosphorus retaining material, e. g., activated alumina, and a downstream section comprising a vanadium oxide containing catalyst, e. g., a vanadia/titania catalyst. It has surprisingly been found that vanadium oxide catalysts are poisoned by phosphorus which may be contained in the form of phosphorus contaminant compounds in the gas to be treated, so that the positioning of a phosphorus-retaining material upstream of the catalyst prolongs catalyst life. In operation, the gas to be treated is passed first through the phosphorus getter upstream section of the catalyst composition and then contacted in the presence of ammonia with downstream section catalytic material.
Inventors
- 👤 Ronald M. Heck
- 👤 Carl D. Keith
- 👤 Robert J. Farrauto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 23:46
CPC Classifications
F; F01; F01N; F01N13/00; F01N13/08; F01N13/085; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01D53/9418; B01D53/9431; B01J; B01J35/00; B01J35/19; B01D2251/00; B01D2251/20; B01D2251/206; B01D2251/2062; B01D2255/00; B01D2255/20; B01D2255/207; B01D2255/20707; B01D2255/20723; B01D2255/209; B01D2255/2092; B01D2255/90; B01D2255/903; B01D2255/9032; B01D2255/92; B01D2255/9207; B01D2258/00; B01D2258/01; B01D2258/012; B01J23/00; B01J23/16; B01J23/20; B01J23/22; B01J35/50; B01J35/56; B01J35/60; B01J35/61; B01J35/613; B01J35/615; F01N2510/00; F01N2510/06; F01N2510/068; F01N2510/0682; F01N2570/00; F01N2570/08
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
70 words
A catalyst composition effective for selective catalytic reduction of nitrogen oxides with ammonia in a gas stream, the composition having an upstream section and a downstream section as sensed relative to the gas flow path through the composition, the upstream section comprising a phosphorus getter comprised of a phosphorus-retaining material, and the downstream section comprising a catalytic member comprised of a catalytic material containing a catalytically-effective amount of vanadium oxide.
Claim 2
Dependent Claim
70 words
A catalyst composition effective for selective catalytic reduction of nitrogen oxides with ammonia in a gas stream, the composition having an upstream section and a downstream section as sensed relative to the gas flow path through the composition, the upstream section comprising a phosphorus getter comprised of a phosphorus-retaining material, and the downstream section comprising a catalytic member comprised of a catalytic material containing a catalytically-effective amount of vanadium oxide.
Claim 3
Dependent Claim
16 words
The composition of claim 1 wherein the catalytic material further comprises a refractory metal oxide support.
Claim 4
Dependent Claim
35 words
The composition of claim 2 wherein the phosphorus getter comprises a refractory carrier on which the phosphorus-retaining material is disposed and the catalytic member comprises a refractory carrier on which the catalytic material is disposed.
Claim 5
Dependent Claim
13 words
The composition of claim 2 wherein the refractory metal oxide support comprises titania.
Claim 6
Dependent Claim
11 words
The composition of claim 1 wherein the phosphorus-retaining material comprises alumina.
Claim 7
Dependent Claim
20 words
The composition of claim 5 wherein the alumina has a surface area of about 10 to 400 m 2 /gm.
Claim 8
Dependent Claim
28 words
The composition of claim 2 wherein the vanadium oxide comprises about 0.5 to 15X by weight of the combined weight of the vanadium oxide and refractory metal oxide.
Claim 9
Dependent Claim
112 words
A catalyst composition effective for selective catalytic reduction of nitrogen oxides with ammonia in a gas stream, the composition having an upstream section and a downstream section as sensed relative to the gas flow path through the composition; the upstream section comprising a phosphorus getter comprised of a refractory honeycomb-like carrier having a plurality of gas flow passages extending therethrough, the passages being coated with a phosphorus-retaining material; and the downstream section comprising a catalytic member comprised of a refractory honeycomb-like carrier having a plurality of gas-flow passages extending therethrough, the passages being coated with a catalytic material comprising a catalytically effective amount of vanadium oxide on a refractory metal oxide support.
Claim 10
Dependent Claim
112 words
A catalyst composition effective for selective catalytic reduction of nitrogen oxides with ammonia in a gas stream, the composition having an upstream section and a downstream section as sensed relative to the gas flow path through the composition; the upstream section comprising a phosphorus getter comprised of a refractory honeycomb-like carrier having a plurality of gas flow passages extending therethrough, the passages being coated with a phosphorus-retaining material; and the downstream section comprising a catalytic member comprised of a refractory honeycomb-like carrier having a plurality of gas-flow passages extending therethrough, the passages being coated with a catalytic material comprising a catalytically effective amount of vanadium oxide on a refractory metal oxide support.
Claim 11
Dependent Claim
37 words
The composition of claim 8 wherein the phosphorus-retaining material is activated alumina and the catalytic material contains about 0.5 to 15X by weight vanadium oxide and comprises about 2 to 25X by weight of the catalytic member.
Claim 12
Dependent Claim
13 words
The composition of claim 9 wherein the refractory metal oxide is predominantly titania.
Claim 13
Dependent Claim
50 words
The composition of claim 9 wherein the alumina has a surface area of about 10 to 400 m 2 /gm, and the catalytic material is comprised of about 1 to 10X by weight vanadium oxide and comprises about 5 to 15% by weight of the weight of the catalyst member.
Claim 14
Dependent Claim
22 words
A process of treating a gas containing phosphorus contaminant and nitrogen oxides to selectively catalytically reduce the nitrogen oxides with ammonia, comprising:
Claim 15
Dependent Claim
22 words
A process of treating a gas containing phosphorus contaminant and nitrogen oxides to selectively catalytically reduce the nitrogen oxides with ammonia, comprising:
Claim 16
Dependent Claim
70 words
(a) flowing the gas through a phosphorus getter comprising a phosphorus-retaining material to remove phosphorus contaminant from the gas; and (b) flowing the resultant phosphorus contaminant-depleted gas through a catalytic member comprising a catalytic material containing a catalytically-effective amount of vanadium oxide, and contacting the gas with the vanadium oxide in the presence of ammonia at a temperature sufficiently high to reduce nitrogen oxides to nitrogen by reaction with ammonia.
Claim 17
Dependent Claim
70 words
(a) flowing the gas through a phosphorus getter comprising a phosphorus-retaining material to remove phosphorus contaminant from the gas; and (b) flowing the resultant phosphorus contaminant-depleted gas through a catalytic member comprising a catalytic material containing a catalytically-effective amount of vanadium oxide, and contacting the gas with the vanadium oxide in the presence of ammonia at a temperature sufficiently high to reduce nitrogen oxides to nitrogen by reaction with ammonia.
Claim 18
Dependent Claim
22 words
The process of claim 12 wherein the gas is introduced into the catalytic member at a temperature of at least about 250°C.
Claim 19
Dependent Claim
25 words
The process of claim 13 wherein the phosphorus-retaining material comprises activated alumina and the catalytic material comprises vanadium oxide and a refractory metal oxide support.
Claim 20
Dependent Claim
41 words
The process of claim 14 wherein the catalytic material comprises about 0.5 to 15X by weight vanadium oxide on a predominantly titania support and the phosphorus-retaining material comprises alumina having a surface area of about 10 to 400 m 2 /gm.
Claim 21
Dependent Claim
68 words
The process of claim 15 wherein step (a) comprises flowing the gas through a phosphorus getter comprising a honeycomb-like structure having a plurality of gas flow passages extending therethrough and coated with the phosphorus-retaining material, and step (b) comprises flowing the resultant phosphorus contaminant-depleted gas through a catalytic member comprising a refractory carrier having a plurality of gas flow passages extending therethrough and coated with the catalytic material.
Claim 22
Dependent Claim
23 words
The process of claim 16 wherein the catalytic material comprises about 2 to 25X by weight of the weight of the catalyst member.
Claim 23
Dependent Claim
18 words
The process of claim 17 wherein the catalytic material comprises about 1 to 10% by weight vanadium oxide.
Claim 24
Dependent Claim
34 words
The process of claim 12 wherein the ammonia is present in necessary at least about 70% of the stoichiometric amount/to react with all of the nitrogen oxides present to reduce the latter to nitrogen.
Claim 25
Dependent Claim
22 words
The process of claim 12 wherein the gas is introduced into the catalytic member at a temperature of about 250 to 400°C.
References Cited (Backward Citations)
No citation records indexed.
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