US4569783A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydroquinone catalyzed oxygen scavenger and methods of use thereof
Assignee: Veolia WTS USA Inc
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Filing: 1984-11-01
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Granted: 1986-02-11
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Expires: 2004-11-01
Abstract
Abstract Compositions and methods for chemically scavenging oxygen from an aqueous medium are disclosed. Salicylaldehyde catalyzed by hydroquinone can be used as an oxygen scavenger in any aqueous medium, but is especially well adapted for use in boiler water systems.
Inventors
- 👤 John A. Muccitelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:37
CPC Classifications
C; C09; C09K; C09K15/00; C09K15/04; C09K15/20; C09K15/24
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
14 words
Oxygen scavenging composition comprising: (a) salicylaldehyde, and a catalytically effective amount of (b) hydroquinone.
Claim 2
Dependent Claim
14 words
Oxygen scavenging composition comprising: (a) salicylaldehyde, and a catalytically effective amount of (b) hydroquinone.
Claim 3
Dependent Claim
28 words
Composition as defined in claim 1 further comprising a (c) neutralizing amine, the weight ratio of (a):(b):(c) being within the range of 1: 0.001 to 0.00004:1.2 to 0.01.
Claim 4
Dependent Claim
9 words
Composition as defined in claim 2 further comprising water.
Claim 5
Dependent Claim
27 words
Composition as defined in claim 2 wherein said neutralizing amine comprises a member or members selected from the group consisting of methoxypropylamine, diethylaminoethanol, dimethylpropanolamine, 2-amine-2-methyl-1-propanol and ammonia.
Claim 6
Independent Claim
34 words
A method for reducing the amount of oxygen in an aqueous medium comprising adding to said medium an effective amount for the purpose of a treatment comprising salicylaldehyde and a catalytic amount of hydroquinone.
Claim 7
Independent Claim
34 words
A method for reducing the amount of oxygen in an aqueous medium comprising adding to said medium an effective amount for the purpose of a treatment comprising salicylaldehyde and a catalytic amount of hydroquinone.
Claim 8
Dependent Claim
14 words
A method as recited in claim 5 wherein said treatment comprises an aqueous solution.
Claim 9
Dependent Claim
45 words
A method as recited in claim 5 wherein said treatment is admitted in an amount sufficient to provide in said aqueous medium from about 2 to 200 parts of salicylaldehyde and from about 0.0004 to 0.040 parts hydroquinone, per million parts of said aqueous medium.
Claim 10
Dependent Claim
40 words
A method as recited in claim 7 further comprising adding a neutralizing amine to said aqueous medium in an amount of from about 0.1 to 50 parts of said neutralizing amine based upon one million parts of said aqueous medium.
Claim 11
Dependent Claim
28 words
A method as recited in claim 8 wherein said neutralizing amine comprises a member or members selected from the group consisting of methoxypropylamine, diethylaminoethanol, dimethylpropanolamine, 2-amino-2-methyl-1-propanol and ammonia.
Claim 12
Dependent Claim
13 words
A method as recited in claim 9 wherein said neutralizing amine comprises methoxypropylamine.
Claim 13
Dependent Claim
16 words
A method as recited in claim 5 wherein said aqueous medium comprises feedwater to a boiler.
Claim 14
Dependent Claim
19 words
A method as recited in claim 5 wherein said aqueous medium comprises condensed steam in a boiler condensate system.
Claim 15
Independent Claim
16 words
A method as recited in claim in 5 wherein said aqueous medium has an alkaline pH.
Claim 16
Dependent Claim
15 words
A method as recited in claim 13 wherein said pH is about 8 or greater.
Claim 17
Dependent Claim
21 words
A method as recited in claim 8 wherein said solution is an aqueous solution and wherein said neutralizing amine comprises methoxypropylamine.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-10 | 1989-08-12 | 1990-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-10 | 1993-08-12 | 1994-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-10 | 1997-08-12 | 1998-02-11 | $7700.00 | Window Closed / Lapsed |