EP0062718A1
Expired / Lapsed
EP
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Method and composition for treating aqueous mediums
Assignee: BetzDearborn Europe Inc
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Filing: 1981-10-30
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Granted: —
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Expires: 2001-10-30
Abstract
Abstract There are disclosed a method and a composition for inhibiting scale formation and dispersing solids particulate matter in aqueous mediums. The composition comprises an acrylic acid/lower alkyl hydroxy acrylate copolymer (1) in combination with a water soluble polymeric material (II) having the formula wherein a or b may be zero or a positive integer, with the proviso that a + b > 1; and wherein d is H or HSO 3 . The method comprises administering an effective amount of each of copolymer (I) and water soluble polymeric material (II) to the particulate aqueous system for which treatment is desired.
Inventors
- 👤 William Richard Snyder
- 👤 Diane Feuerstein
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 05:45
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/12
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
198 words
.Composition for controlling the deposition of scale imparting precipitates on the structural parts of a system exposed to an aqueous medium containing scale imparting precipitates under deposit forming conditions, said composition also being adapted for dispersing solids particulate matter, characterized in that said composition comprises an effective amount for the purpose of a water soluble polymer (I) comprising moieties (a) derived from an acrylic acid or water soluble salt thereof, and moieties (b)'of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formula wherein R is hydrogen or a lower alkyl of from about 1 to 3 carbon atoms, R 1 is OH, OM, or NH 2 where_M is a water soluble cation, R 2 is a lower alkyl group of from about 2-6 carbon atoms and the molar ratio of x:y is about 34:1 to 1:4; and an effective amount for the purpose of a water soluble polymer. (II) or water soluble salt or hydrolgsate acid form thereof said polymer (II). having the formula: wherein a or b may be zero or a positive integer, with the proviso that (a + b) must be >1, d = H or HSO 3 .
Claim 2
Dependent Claim
198 words
.Composition for controlling the deposition of scale imparting precipitates on the structural parts of a system exposed to an aqueous medium containing scale imparting precipitates under deposit forming conditions, said composition also being adapted for dispersing solids particulate matter, characterized in that said composition comprises an effective amount for the purpose of a water soluble polymer (I) comprising moieties (a) derived from an acrylic acid or water soluble salt thereof, and moieties (b)'of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formula wherein R is hydrogen or a lower alkyl of from about 1 to 3 carbon atoms, R 1 is OH, OM, or NH 2 where_M is a water soluble cation, R 2 is a lower alkyl group of from about 2-6 carbon atoms and the molar ratio of x:y is about 34:1 to 1:4; and an effective amount for the purpose of a water soluble polymer. (II) or water soluble salt or hydrolgsate acid form thereof said polymer (II). having the formula: wherein a or b may be zero or a positive integer, with the proviso that (a + b) must be >1, d = H or HSO 3 .
Claim 3
Dependent Claim
45 words
Composition as claimed in claim 1, characterized in that said scale imparting precipitates are selected from the group consisting of calcium carbonate, calcium phosphate and calcium sulphate and said solids particulate matter is selected from the group consisting of iron oxide, clay and mixtures thereof.
Claim 4
Dependent Claim
25 words
Composition as claimed in claim 1 or 2, charac- terized in that said polymer (II) is a sulfonated styrene/ maleic anhydride copolymer having the formula
Claim 5
Dependent Claim
17 words
Composition as claimed in claim 3, characterized in that the molar ratio of a:b is about 3:1.
Claim 6
Dependent Claim
23 words
Composition as claimed in claim 3 or 4, characterized in that the molecular weight of said sulfonated styrene/maleic anhydride copolymer is about 1500.
Claim 7
Dependent Claim
20 words
Composition as claimed in claim 1, characterized in that said polymer (II) is a sulfonated styrene polymer having the formula
Claim 10
Dependent Claim
20 words
Composition as claimed in claim 6, characterized in that said sulfonated styrene polymer has a molecular weight of about 70,000.
Claim 11
Dependent Claim
20 words
Composition as claimed in claim 1, characterized in that said polymer (II) is a styrene/maleic anhydride polymer having the formula
Claim 12
Dependent Claim
17 words
Composition as claimed in claim 8, characterized in that the molar ratio of a:b is about 1:1.
Claim 13
Dependent Claim
22 words
Composition as defined in claim 8 or 9, characterized in that said styrene/maleic anhydride polymer has a molecular weight of about 1600.
Claim 14
Dependent Claim
20 words
Composition as claimed in claim 1, characterized in that said polymer (II) is a polymaleic anhydride polymer having the formula
Claim 15
Dependent Claim
20 words
Composition as claimed in claim 11, characterized in that the molecular weight of said polymaleic anhydride polymer is about 800-1000.
Claim 16
Dependent Claim
52 words
.13. Composition as claimed in any one of the preceding claims, characterized in that said polymer (I) comprises acrylic acid/2-hydroxypropyl acrylate copolymer, wherein the molar ratio of acrylic acid to 2 hydroxypropyl acrylate copolymer is about 3:1 and wherein the molecular weight of said acrylic acid/2 hydroxypropyl acrylate copolymer is about 6,000.
Claim 17
Dependent Claim
124 words
Method of treating an aqueous medium so as to (i) control the deposition of scale imparting precipitates on the structural parts of a system exposed to an aqueous medium containing scale imparting precipitates under deposit forming conditions, and/or (ii) disperse and maintaining dispersed particulate- matter in such a system having an aqueous medium which contains particulate matter; which method is characterized by adding to said aqueous medium an effective amount for the purpose of a water soluble polymer (I) as defined in claim 1 or 13; and also adding to said aqueous medium and effective amount for the purpose of a water soluble polymer (II) as defied in any one of claims 1 to 12, or water soluble salt or hydrolysate acid form thereof.
Claim 18
Dependent Claim
47 words
Method as claimed in claim 14, characterized in that. said scale imparting precipitates are selected from the group consisting of calcium carbonate, calcium phosphate and calcium sulphate and said solids particulate . matter is selected from the group consisting of clay, iron . oxide and mixtures thereof.
Claim 19
Dependent Claim
57 words
Method as claimed in claim 14 or 15, characterized in that the molar ratio of polymer (I) to polymer (II) is about 10:1 to 1:10, and wherein said polymer (I) and polymer (II) are added to said aqueous medium in an amount of about 0.1-500 parts polymer (I) and (II) per million parts of said aqueous medium.
Claim 20
Dependent Claim
18 words
Method as claimed in claim 14 or 15, characterized in that said system is a steam generating system.
Claim 21
Dependent Claim
18 words
Method as claimed in claim 14 or 15, characterized in that said system is a cooling water system.
Claim 22
Dependent Claim
27 words
Method as claimed in any one of claims 14 to 18, characterized in that said polymer (I) has a molecular weight of from about 500 to 1,000,000.
Claim 23
Dependent Claim
34 words
Method as claimed in any one of claims 14 to 19, characterized in that said polymer (I) comprises a copolymer of acrylic acid or a water soluble salt thereof and 2-hydroxypropyl acrylate or hydroxyethylacrylate.
Claim 24
Dependent Claim
33 words
Aqueous medium characterized by having been treated by a composition as claimed in any one of claims 1 to 13, or a method as claimed in any one of claims 14 to 20.
References Cited (Backward Citations)
FR2223308A1
Cited
US4048066A
Cited
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