Patent US4886650A successfully refreshed from Google Patents.
US4886650A
Expired / Lapsed
US
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No reduction using sublimation of cyanuric acid
Assignee: Individual
•
Filing: 1988-03-15
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Granted: 1989-12-12
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Expires: 2008-03-15
Abstract
Abstract An arrangement for reducing the NO content of a gas stream comprises contacting the gas stream with HNCO at a temperature effective for heat induced decomposition of HNCO and for resultant lowering of the NO content of the gas stream. Preferably, the HNCO is generated by sublimation of cyanuric acid and CO or other H-atom generating species is also present or added to the gas stream.
Inventors
- 👤 Robert Perry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:26
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/54; B01D53/56
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
56 words
A method of reducing the NO content of a gas stream comprising contacting the gas stream with HNCO in the presence of an amount of carbon monoxide effective to produce or regenerate H atoms, at a temperature effective for heat induced decomposition of HNCO and for resultant lowering of the NO content of the gas stream.
Claim 2
Independent Claim
56 words
A method of reducing the NO content of a gas stream comprising contacting the gas stream with HNCO in the presence of an amount of carbon monoxide effective to produce or regenerate H atoms, at a temperature effective for heat induced decomposition of HNCO and for resultant lowering of the NO content of the gas stream.
Claim 3
Dependent Claim
15 words
A method of claim 1, wherein the HNCO is generated by sublimation of cyanuric acid.
Claim 4
Dependent Claim
23 words
A method of claim 2, wherein the gas is contacted with HNCO at a temperature of about 500° C. to about 800° C.
Claim 5
Dependent Claim
73 words
A method of claim 1, wherein said contacting is carried out in the presence of a surface which is effective as a catalyst for at least one of the reactions between heat induced decomposition products of HNCO and other components in said gas stream, which reactions lead to lowering of the NO content of the gas streams or is effective as a catalyst for generating free radicals in the thermal decomposition of HNCO.
Claim 6
Dependent Claim
31 words
A method of claim 1, wherein the HNCO is generated by sublimation of a sublimable substituted derivative of cyanuric acid which produces the HNCO upon sublimation, or by sublimation of cyamelide.
Claim 7
Dependent Claim
15 words
A method of claim 2, wherein the NO-containing gas stream is an effluent gas stream.
Claim 8
Dependent Claim
13 words
A method of claim 1, wherein CO is added to the gas stream.
Claim 9
Independent Claim
58 words
A method of reducing the NO content of a gas steam comprising contacting the gas stream with HNCO in the presence of another added compound in an amount effective for production or regeneration of H atoms, at a temperature effective for heat induced decomposition of HNCO and for resultant lowering of the NO content of the gas stream.
Claim 10
Independent Claim
58 words
A method of reducing the NO content of a gas steam comprising contacting the gas stream with HNCO in the presence of another added compound in an amount effective for production or regeneration of H atoms, at a temperature effective for heat induced decomposition of HNCO and for resultant lowering of the NO content of the gas stream.
Claim 11
Dependent Claim
13 words
A method of claim 8, wherein the added compound is an unsaturated hydrocarbon.
Claim 12
Dependent Claim
13 words
A method of claim 9, wherein the added compound is ethylene or acetylene.
Claim 13
Dependent Claim
17 words
A method of claim 9, wherein the added compound is a branched alkene or a branched alkyne.
Claim 14
Dependent Claim
12 words
A method of claim 1, wherein said CO is of exogenous origin.
Claim 15
Dependent Claim
28 words
A method of claim 12, wherein said CO is added to the gas stream by mixing with a separate CO-containing gas stream or by direct injection of CO.
Claim 16
Dependent Claim
12 words
A method of claim 1, wherein said CO is of endogenous origin.
Claim 17
Dependent Claim
86 words
A method of claim 14, wherein said gas stream is an effluent gas stream from a first combustion apparatus, and said CO is produced by operating said first apparatus under conditions producing CO, or by operating a secondary combustion apparatus using a minor portion of the fuel of said first combustion apparatus under conditions producing a CO-containing effluent and mixing the latter with the gas stream, or by placing in contact with said stream, a catalyst effective to generate CO upon contact with said gas stream.
Claim 18
Dependent Claim
34 words
A method of claim 1, wherein the NO-containing gas stream is generated by a chemical reaction and HNCO or a compound which produces HNCO in said NO-containing gas stream is introduced into said reaction.
Claim 19
Dependent Claim
27 words
A method of claim 16, wherein HNCO or a compound which produces HNCO in said NO-containing gas stream is introduced in a feed stream for said reaction.
Claim 20
Dependent Claim
34 words
A method of claim 8, wherein the NO-containing gas stream is generated by a chemical reaction and HNCO or a compound which produces HNCO in said NO-containing gas stream is introduced into said reaction.
Claim 21
Dependent Claim
27 words
A method of claim 18, wherein HNCO or a compound which produces HNCO in said NO-containing gas stream is introduced in a feed stream for said reaction.
Claim 22
Dependent Claim
35 words
A method of claim 1, wherein the HNCO has not been generated substantially by addition directly to the NO-containing stream per se of solid cyanuric acid particles of a diameter of 0.1 to 10 mm.
Claim 23
Dependent Claim
26 words
A method of claim 1, wherein HNCO or a compound which produces HNCO in said NO-containing gas stream is added directly to said NO-containing gas stream.
Claim 24
Dependent Claim
26 words
A method of claim 8, wherein HNCO or a compound which produces HNCO in said NO-containing gas stream is added directly to said NO-containing gas stream.
Claim 25
Dependent Claim
34 words
A method of claim 1, wherein said HNCO is generated under conditions substantially optimized for reducing the NO content of the gas stream by contact therewith of HNCO or decomposition products derived from HNCO.
Claim 26
Dependent Claim
11 words
A method of claim 16, wherein said chemical reaction is combustion.
Claim 27
Dependent Claim
11 words
A method of claim 18, wherein said chemical reaction is combustion.
References Cited (Backward Citations)
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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) | 1992-12-11 | 1993-06-12 | 1993-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-11 | 1997-06-12 | 1997-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-11 | 2001-06-12 | 2001-12-12 | $7700.00 | Window Closed / Lapsed |