US4120655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the inhibition of corrosion of ferrous metals in an aqueous medium
Assignee: Societe National Elf Aquitaine
•
Filing: 1977-07-11
•
Granted: 1978-10-17
•
Expires: 1997-07-11
Abstract
Abstract The method for the inhibition of corrosion of ferrous metals in an aqueous medium consists in adding to the aqueous medium 10 to 2000 ppm of a mixture constituted by a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydroxycarboxylic acid and by a phosphoric ester of alkanolamine.
Inventors
- 👤 Michel Crambes
- 👤 Henri Grangette
- 👤 Pierre Pivette
- 👤 Philippe Haicour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:43
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
A method for the inhibition of corrosion of ferrous metals in an aqueous medium consisting of adding to the aqueous medium from about 10 to 2000 ppm of a mixture consisting essentially of a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydrocarboxylic acid selected from the group consisting of tartaric, citric, maleic, gluconic and salicylic acids together with a phosphoric ester of an alkanolamine.
Claim 2
Independent Claim
75 words
A method for the inhibition of corrosion of ferrous metals in an aqueous medium consisting of adding to the aqueous medium from about 10 to 2000 ppm of a mixture consisting essentially of a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydrocarboxylic acid selected from the group consisting of tartaric, citric, maleic, gluconic and salicylic acids together with a phosphoric ester of an alkanolamine.
Claim 3
Dependent Claim
18 words
A method according to claim 1, wherein the phosphoric ester of alkanolamine is a phosphoric ester of diethanolamine.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein the mixture is employed in the form of a solution.
Claim 5
Dependent Claim
15 words
A method according to claim 1, wherein the aqueous medium has a high salt content.
Claim 6
Dependent Claim
30 words
A method according to claim 1, wherein the metal employed for salifying the hydroxycarboxylic acid is selected from the group consisting of zinc, iron, nickel, manganese, cobalt, cadmium and lead.
Claim 7
Dependent Claim
12 words
A method according to claim 5, wherein the salifying metal is zinc.
References Cited (Backward Citations)
US3518203A
Cited
US3699052A
Cited
US3714066A
Cited
US3718603A
Cited
US3723347A
Cited
US3873465A
Cited
US3868217A
Cited
US4066398A
Cited
US3932303A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-16 | 1982-04-17 | 1982-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-16 | 1986-04-17 | 1986-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-16 | 1990-04-17 | 1990-10-17 | $7700.00 | Window Closed / Lapsed |