US4744950A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of inhibiting the corrosion of copper in aqueous mediums
Assignee: Veolia WTS USA Inc
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Filing: 1986-08-22
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Granted: 1988-05-17
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Expires: 2006-08-22
Abstract
Abstract A method of providing a durable, long lasting chemically resistant, pH tolerant, corrosion inhibiting film on the surfact of copper or copper containing metal in contact with an aggressive aqueous system is disclosed. The copper or copper containing metal generally composes a structure of dynamic cooling water system, and protection is afforded thereto by intermittently feeding to the aqueous medium a sufficient amount of a C3 to C6 alkyl substituted benzotriazole.
Inventors
- 👤 Orin Hollander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:20
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10; C23F11/14; C23F11/149
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
104 words
A method of providing a durable, long lasting chemically resistant, pH tolerant, corrosion inhibiting film on the surface of copper or copper containing metal in contact with an aggressive dynamic aqueous system substantially free of glycols having a pH substantially neutral to alkaline which comprises adding in a non-continuous manner a sufficient amount for the purpose of an alkyl benzotriazole having the formula ##STR2## where R is a C 3 to C 6 linear hydrocarbon, and permitting contact of said triazole for a time sufficient to provide said film and thereafter discontinuing the feed of said triazole and permitting any residual triazole to deplete.
Claim 2
Independent Claim
104 words
A method of providing a durable, long lasting chemically resistant, pH tolerant, corrosion inhibiting film on the surface of copper or copper containing metal in contact with an aggressive dynamic aqueous system substantially free of glycols having a pH substantially neutral to alkaline which comprises adding in a non-continuous manner a sufficient amount for the purpose of an alkyl benzotriazole having the formula ##STR2## where R is a C 3 to C 6 linear hydrocarbon, and permitting contact of said triazole for a time sufficient to provide said film and thereafter discontinuing the feed of said triazole and permitting any residual triazole to deplete.
Claim 3
Dependent Claim
16 words
A method according to claim 1, wherein R is a C 3 or C 4 .
Claim 4
Dependent Claim
20 words
A method according to claim 2 wherein from 0.1 to 100 ppm of alkyl benzotriazole is added to the system.
Claim 5
Dependent Claim
15 words
A method according to claim 3 wherein from about 1 to 50 ppm is added.
Claim 6
Dependent Claim
13 words
A method according to claim 4 wherein the alkyl benzotriazole is fed intermittently.
Claim 7
Dependent Claim
23 words
A method according to claim 5 wherein the time frames of the intermittent feed are predicated upon the durability of the film formed.
Claim 8
Independent Claim
20 words
A method according to any one of claims 2, 4, 5 or 6 wherein the alkyl benzotriazole is butyl benzotriazole.
Claim 9
Independent Claim
123 words
A method of providing a durable, long lasting chemically resistant, pH tolerant, corrosion inhibiting film on the surface of copper or copper containing metal of an open cooling water system which copper or metal is in contact with a dynamic aggressive aqueous medium of said system, which medium is substantially free of glycols and has a pH substantially neutral to alkaline, which method comprises adding in a non-continuous manner a sufficient amount for the purpose of an alkyl benzotriazole having the formula ##STR3## where R is a C 3 to C 6 linear hydrocarbon, and permitting contact of said triazole for a time sufficient to provide said film and thereafter discontinuing the feed of said triazole and permitting any residual triazole to deplete.
Claim 10
Independent Claim
123 words
A method of providing a durable, long lasting chemically resistant, pH tolerant, corrosion inhibiting film on the surface of copper or copper containing metal of an open cooling water system which copper or metal is in contact with a dynamic aggressive aqueous medium of said system, which medium is substantially free of glycols and has a pH substantially neutral to alkaline, which method comprises adding in a non-continuous manner a sufficient amount for the purpose of an alkyl benzotriazole having the formula ##STR3## where R is a C 3 to C 6 linear hydrocarbon, and permitting contact of said triazole for a time sufficient to provide said film and thereafter discontinuing the feed of said triazole and permitting any residual triazole to deplete.
Claim 11
Dependent Claim
15 words
A method according to claim 8 wherein R is C 4 or C 5 .
Claim 12
Dependent Claim
20 words
A method according to claim 9 wherein from 0.1 to 100 ppm of alkyl benzotriazole is added to the system.
Claim 13
Dependent Claim
15 words
A method according to claim 10 wherein from about 1 to 50 ppm is added.
Claim 14
Dependent Claim
13 words
A method according to claim 11 wherein the alkyl benzotriazole is fed intermittently.
Claim 15
Dependent Claim
22 words
A method according to claim 12 wherein the periods for the intermittent feed are predicated upon the durability of the film formed.
Claim 16
Independent Claim
19 words
A method according to any one of claims 9, 10, 11 or 12 wherein the benzotriazole is n-butyl benzotriazole.
Claim 17
Dependent Claim
17 words
A method according to claim 14 wherein the cooling water system is an open recirculating water system.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-17 | 1991-11-16 | 1992-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-17 | 1995-11-16 | 1996-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-17 | 1999-11-16 | 2000-05-17 | $7700.00 | Window Closed / Lapsed |