US4253969A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Deposit control through the use of oligomeric phosphonic acid derivatives
Assignee: Veolia WTS USA Inc
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Filing: 1979-07-16
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Granted: 1981-03-03
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Expires: 1999-07-16
Abstract
Abstract The present disclosure is directed to oligomeric phosphonic acid derivatives which possess excellent chlorine resistance and acceptable calcium tolerance and which, at substoichiometric amounts, inhibit the formation of scale in aqueous mediums. Additionally, the oligomers have been found to be quite active as dispersants for particulate matter contained in an aqueous medium.
Inventors
- 👤 Larry W. Becker
- 👤 Philip S. Davis
- 👤 Ian D. Morrison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:09
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
115 words
A method of dispersing iron hydroxide particulate matter contained in an aqueous medium, and thereby controlling the settling thereof on the structural parts of the system bearing said medium, which comprises adding to said system an effective amount for the purpose of a water soluble, chlorine-resistant, high calcium tolerance phosphonate having the formula ##STR12## wherein R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to and including 13; Y is (i) a mixture of ##STR13## with H and/or ##STR14## and (ii) C x H 2x+1 where x is as above defined; M is a water soluble cation; and n is 1 or greater.
Claim 2
Independent Claim
115 words
A method of dispersing iron hydroxide particulate matter contained in an aqueous medium, and thereby controlling the settling thereof on the structural parts of the system bearing said medium, which comprises adding to said system an effective amount for the purpose of a water soluble, chlorine-resistant, high calcium tolerance phosphonate having the formula ##STR12## wherein R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to and including 13; Y is (i) a mixture of ##STR13## with H and/or ##STR14## and (ii) C x H 2x+1 where x is as above defined; M is a water soluble cation; and n is 1 or greater.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein the amount added is from about 0.5 to about 600 parts per million parts of said medium.
Claim 4
Dependent Claim
15 words
A method according to claim 2, wherein n is from about 1 to about 16.
Claim 5
Dependent Claim
14 words
A method according to claim 3, wherein the system is a cooling water system.
Claim 6
Dependent Claim
14 words
A method according to claim 3, wherein the system is a gas scrubber system.
Claim 7
Dependent Claim
30 words
A method according to claim 1, wherein the phosphonate is added to said system in an amount ranging from 0.5 to 100 parts per million parts of said aqueous medium.
Claim 8
Dependent Claim
15 words
A method according to claim 6, wherein n is from about 1 to about 16.
Claim 9
Dependent Claim
14 words
A method according to claim 7, wherein the system is a cooling water system.
Claim 10
Dependent Claim
14 words
A method according to claim 7, wherein the system is a gas scrubber system.
Claim 11
Dependent Claim
30 words
A method according to claim 1, wherein R 1 and R 2 are C 2 H 5 , Y is hydrogen and n is from about 1 to about 16.
Claim 12
Dependent Claim
30 words
A method according to claim 10, wherein the phosphonate is added to said system in an amount ranging from 0.5 to 600 parts per million parts of said aqueous medium.
Claim 13
Dependent Claim
14 words
A method according to claim 11, wherein the system is a cooling water system.
Claim 14
Dependent Claim
14 words
A method according to claim 11, wherein the system is a gas scrubber 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) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |