Patent US4642194A successfully refreshed from Google Patents.
US4642194A
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Method for prevention of phosphonate decomposition by chlorine
Assignee: Ecolab USA Inc
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Filing: 1985-09-16
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Granted: 1987-02-10
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Expires: 2005-09-16
Abstract
Abstract The decomposition of phosphonates by chlorine in industrial process waters can be diminished or prevented by treating such waters with certain water-soluble nitrogen-containing compounds.
Inventors
- 👤 Donald A. Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:13
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
83 words
A method of preventing the decomposition of phosphonates from the group consisting of: 1,1-hydroxyethylidene diphosphonic acid; tris aminomethane phosphonic acid; 1-phosphono glycolic acid; ethylene diamine tetra(methylenephosphonic acid): Hexamethylene diamine tetra(methylenephosphonic acid); and, diethylene triamine penta(methylenephosphonic acid); which are present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
Claim 2
Independent Claim
83 words
A method of preventing the decomposition of phosphonates from the group consisting of: 1,1-hydroxyethylidene diphosphonic acid; tris aminomethane phosphonic acid; 1-phosphono glycolic acid; ethylene diamine tetra(methylenephosphonic acid): Hexamethylene diamine tetra(methylenephosphonic acid); and, diethylene triamine penta(methylenephosphonic acid); which are present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
Claim 3
Dependent Claim
24 words
The method of claim 1 where the dosage of the sulfamic acid is at least 1/2 ppm for each ppm of Cl 2 .
Claim 4
Independent Claim
67 words
A method of preventing the decomposition of phosphonates from the group consisting of: 1,1-hydroxyethylidine diphosphonic acid; and, 1-phosphono glycolic acid; which are present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
Claim 5
Independent Claim
67 words
A method of preventing the decomposition of phosphonates from the group consisting of: 1,1-hydroxyethylidine diphosphonic acid; and, 1-phosphono glycolic acid; which are present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
Claim 6
Independent Claim
57 words
A method of preventing the decomposition of 1,1-hydroxyethylidine diphosphonic acid which is present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
Claim 7
Independent Claim
57 words
A method of preventing the decomposition of 1,1-hydroxyethylidine diphosphonic acid which is present in an effective amount to prevent scale in industrial cooling waters which contain an effective amount of chlorine for microbiological control which comprises treating said waters with at least 1/4 ppm of sulfamic acid for each ppm of Cl 2 present in these waters.
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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) | 1990-02-09 | 1990-08-11 | 1991-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-09 | 1994-08-11 | 1995-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-09 | 1998-08-11 | 1999-02-10 | $7700.00 | Window Closed / Lapsed |