US4201669A
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: 1978-09-11
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Granted: 1980-05-06
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Expires: 1998-09-11
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
2026-10-28 07:22
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/14
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
103 words
A method of controlling the formation and subsequent deposition of scale-forming salts on the structural parts of a system having an aqueous medium, which medium contains scale-imparting cations and anions, which comprises adding to said medium a sufficient threshold amount for the purpose of a water soluble, chlorine-resistant phosphonate of high calcium tolerance having the structural formula ##STR12## where R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to and including 4; Y is hydrogen, ##STR13## or mixtures thereof; M is a water soluble cation; and n is 1 or greater.
Claim 2
Independent Claim
103 words
A method of controlling the formation and subsequent deposition of scale-forming salts on the structural parts of a system having an aqueous medium, which medium contains scale-imparting cations and anions, which comprises adding to said medium a sufficient threshold amount for the purpose of a water soluble, chlorine-resistant phosphonate of high calcium tolerance having the structural formula ##STR12## where R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to and including 4; Y is hydrogen, ##STR13## or mixtures thereof; M is a water soluble cation; and n is 1 or greater.
Claim 3
Dependent Claim
15 words
A method according to claim 1, wherein n is from about 1 to about 16.
Claim 4
Dependent Claim
38 words
A method according to claim 2, wherein the phosphonate is added to said aqueous medium in an amount which represents a mole ratio of said cation to said phosphonate of 20 to 1 up to 34,000 to 1.
Claim 5
Dependent Claim
37 words
A method according to claim 1, wherein the scale-imparting ions are cations selected from the group consisting of calcium, magnesium, and mixtures thereof, and anions selected from the group consisting of carbonates, sulfates, or mixtures thereof oxalates.
Claim 6
Dependent Claim
38 words
A method according to claim 4, wherein the phosphonate is added to said aqueous medium in an amount which represents a mole ratio of said cations to said phosphonate of 20 to 1 up to 34,000 to 1.
Claim 7
Dependent Claim
15 words
A method according to claim 5, wherein n is from about 1 to about 16.
Claim 8
Dependent Claim
22 words
A method according to claim 6, wherein M is selected from the group consisting of hydrogen, sodium, potassium, ammonium, or ammonium salts.
Claim 9
Dependent Claim
20 words
A method according to claim 7, wherein both R 1 and R 2 are --CH 3 and Y is hydrogen.
Claim 10
Dependent Claim
32 words
A method according to claim 8, wherein the system is a cooling water system, the aqueous medium is the cooling water, the cations are calcium and magnesium, and the anion is carbonate.
Claim 11
Dependent Claim
26 words
A method according to claim 8, wherein the system is a gas scrubber, the cations are calcium and magnesium, and the anion is sulfate and/or carbonate.
Claim 12
Dependent Claim
27 words
A method according to claim 8, wherein the system is a pulp and/or paper mill system, the cation is calcium, and the anion is carbonate and/or oxalate.
Claim 13
Independent Claim
97 words
A method of controlling the formation and subsequent deposition of calcium phosphate on the structural parts of a system having an aqueous medium, which medium contains calcium and phosphate ions, which comprises adding to said medium a sufficient threshold amount for the purpose of a water soluble, chlorine-resistant phosphonate having the structural formula ##STR14## where R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to 13; Y is hydrogen, ##STR15## or mixtures thereof; M is a water soluble cation; and n is 1 or greater.
Claim 14
Independent Claim
97 words
A method of controlling the formation and subsequent deposition of calcium phosphate on the structural parts of a system having an aqueous medium, which medium contains calcium and phosphate ions, which comprises adding to said medium a sufficient threshold amount for the purpose of a water soluble, chlorine-resistant phosphonate having the structural formula ##STR14## where R 1 and R 2 each represent a group having the formula C x H 2x+1 ; x is from 1 to 13; Y is hydrogen, ##STR15## or mixtures thereof; M is a water soluble cation; and n is 1 or greater.
Claim 15
Dependent Claim
15 words
A method according to claim 12, wherein n is from about 1 to about 16.
Claim 16
Dependent Claim
39 words
A method according to claim 13, wherein the phosphonate is added to said aqueous medium in an amount which represents a mole ratio of said calcium ions to said phosphonate of 20 to 1 up to 34,000 to 1.
Claim 17
Dependent Claim
22 words
A method according to claim 14, wherein M is selected from the group consisting of hydrogen, sodium, potassium, ammonium, or ammonium salts.
Claim 18
Dependent Claim
12 words
A method according to claim 15, wherein x is 1 to 5.
Claim 19
Dependent Claim
22 words
A method according to claim 16, wherein the system is a cooling water system and the aqueous medium is the cooling water.
Claim 20
Dependent Claim
13 words
A method according to claim 16, wherein the system is a gas scrubber.
Claim 21
Dependent Claim
12 words
A method according to claim 12, wherein x is 1 to 5.
Claim 22
Dependent Claim
39 words
A method according to claim 19, wherein the phosphonate is added to such aqueous medium in an amount which represents a mole ratio of said calcium ions to said phosphonate of 20 to 1 up to 34,000 to 1.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1983-05-06 | 1983-11-05 | 1984-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-06 | 1987-11-05 | 1988-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-06 | 1991-11-05 | 1992-05-06 | $7700.00 | Window Closed / Lapsed |