US4944885A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water treatment polymers and methods of use thereof
Assignee: Veolia WTS USA Inc
•
Filing: 1989-10-05
•
Granted: 1990-07-31
•
Expires: 2009-10-05
Abstract
Abstract A water soluble polymer composition is disclosed. The polymer has repeat units characterized by the structural formulae: ##STR1## wherein R 1 is H or lower alkyl (C 1 -C 3 ); R 2 is OH, OM, or NH 2 ; M is a water soluble cation; R 3 is a hydroxy substituted alkyl or alkylene radical having from 1 to about 6 carbon atoms or a non-substituted alkyl or alkylene radical having from 1 to 6 carbon atoms; X is an anionic radical; Z is H or hydrogens or a water soluble cation or cations which together counterbalance the valence of X, and a is 0 or 1. The copolymer is effective in inhibiting the precipitation of certain scale forming salts, and also acts to inhibit corrosion of metal parts in contact with water systems.
Inventors
- 👤 Fu Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:18
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/105; C02F5/12; C02F5/125; C23F14/00; C23F14/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
143 words
A method of controlling the deposition of calcium phosphate on the structural parts of a system exposed to an aqueous medium containing said calcium and phosphate ions under deposit forming conditions, said method comprising adding to said aqueous medium at least about 10 ppm of a water soluble polymer comprising repeat unit moieties (a) and (b) wherein said repeat unit (a) comprises the structure ##STR10## and wherein said repeat unit (b) comprises the structure ##STR11## wherein each R 1 is independently H or lower alkyl (C 1 -C 3 ); R 2 is OH, or OM; M is a water soluble cation; R 3 is 2-hydroxypropylidene; and Z is H or hydrogen atoms or a water soluble cation or cations which together counterbalance the valence of SO 3 ; and the molar ratio x:y of said polymer being between about 8:1 to 1:5.
Claim 2
Independent Claim
143 words
A method of controlling the deposition of calcium phosphate on the structural parts of a system exposed to an aqueous medium containing said calcium and phosphate ions under deposit forming conditions, said method comprising adding to said aqueous medium at least about 10 ppm of a water soluble polymer comprising repeat unit moieties (a) and (b) wherein said repeat unit (a) comprises the structure ##STR10## and wherein said repeat unit (b) comprises the structure ##STR11## wherein each R 1 is independently H or lower alkyl (C 1 -C 3 ); R 2 is OH, or OM; M is a water soluble cation; R 3 is 2-hydroxypropylidene; and Z is H or hydrogen atoms or a water soluble cation or cations which together counterbalance the valence of SO 3 ; and the molar ratio x:y of said polymer being between about 8:1 to 1:5.
Claim 3
Dependent Claim
24 words
A method as recited in claim 1, wherein the number average molecular weight of said water soluble polymer is between about 1,500 to 500,000.
Claim 4
Dependent Claim
24 words
A method as recited in claim 1, wherein the number average molecular weight of said water soluble polymer is between about 1,500 to 20,000.
Claim 5
Dependent Claim
45 words
A method as recited in claim 3, wherein R 1 in both said repeat units (a) and (b) is hydrogen, R 2 is OH, Z is a member or members selected from the group consisting of H, Na, NH 4 + , Ca and K.
Claim 6
Dependent Claim
51 words
A method as recited in claim 3, wherein R 1 in said repeat unit (b) is methyl, R 1 in said repeat unit (a) is H, R 2 is OH, Z is a member or members selected from the group consisting of H, Na, NH 4 + , Ca and K.
Claim 7
Dependent Claim
36 words
A method as recited in claim 4 or 5, wherein said water soluble polymer is added to said aqueous medium in an amount of 10-500 parts polymer based upon 1 million parts of said aqueous medium.
Claim 8
Dependent Claim
15 words
A method as recited in claim 6, wherein said system is a steam generating system.
Claim 9
Dependent Claim
15 words
A method as recited in claim 6, wherein said system is a cooling water system.
Claim 10
Dependent Claim
15 words
A method as recited in claim 6, wherein said system is a gas scrubbing system.
References Cited (Backward Citations)
US2634296A
Cited
US2847477A
Cited
US2723971A
Cited
US2847478A
Cited
US3228979A
Cited
US3262903A
Cited
US3549548A
Cited
US3706717A
Cited
US3799893A
Cited
US3891568A
Cited
US3992318A
Cited
US4018702A
Cited
GB1491701A
Cited
US4046707A
Cited
DE2522637A1
Cited
US3989636A
Cited
US4288327B1
Cited
US4288327A
Cited
US4029577A
Cited
US4209398A
Cited
JPS5375138A
Cited
US4095029A
Cited
US4149969A
Cited
US4207405A
Cited
US4176059A
Cited
US4432879A
Cited
US4324684A
Cited
US4303568A
Cited
JPS56155692A
Cited
JPS587415A
Cited
US4500693A
Cited
JPS589987A
Cited
US4457847A
Cited
US4457847B2
Cited
US4457847B1
Cited
US4469615A
Cited
JPS58147412A
Cited
JPS58154761A
Cited
JPS58171576A
Cited
US4490308A
Cited
US4546156A
Cited
US4659480A
Cited
EP0142929A2
Cited
US4759851A
Cited
US4659482A
Cited
US4659481A
Cited
US4732698A
Cited
US4717499A
Cited
US4701262A
Cited
US4708815A
Cited
US4640793A
Cited
US4560481A
Cited
US4575425A
Cited
US4650591A
Cited
US4671880A
Cited
US4678840A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-30 | 1994-01-29 | 1994-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-30 | 1998-01-29 | 1998-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-30 | 2002-01-29 | 2002-07-31 | $7700.00 | Window Closed / Lapsed |