US4480067A
Expired / Lapsed
US
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Impeding sedimentation of clays in water
Assignee: Societe National Elf Aquitaine
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Filing: 1983-08-24
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Granted: 1984-10-30
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Expires: 2003-08-24
Abstract
Abstract A method for impeding the sedimentation of clays in water by adding a water-soluble compound. This compound is constituted by a polymer bearer of hydroxamic groups attached to a linear hydrocarbon chain. The amount of this adjuvant is small on the order of a few milligrams.
Inventors
- 👤 Lino Vio
- 👤 Gilles Meunier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:59
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/12
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
37 words
A method of impeding the sedimentation of clays in a water containing the same, which consists in adding to the water a slight amount of a polymer which bears hydroxamic groups attached to a linear hydrocarbon chain.
Claim 2
Independent Claim
37 words
A method of impeding the sedimentation of clays in a water containing the same, which consists in adding to the water a slight amount of a polymer which bears hydroxamic groups attached to a linear hydrocarbon chain.
Claim 3
Dependent Claim
22 words
The method according to claim 1, wherein said hydrocarbon chain is selected from the group consisting of polyolefins, polyvinyl, polyacryl and polybutenyl.
Claim 4
Dependent Claim
31 words
Method according to claim 1, wherein sais polymer, which bears hydroxamic groups, is a copolymer of the hydrocarbon chain with acrylic acid, an acrylic ester or a salt of acrylic acid.
Claim 5
Dependent Claim
31 words
Method according to claim 1, wherein said polymer, which bears hydroxamic groups, is a copolymer of the hydrocarbon chain with maleic acid, a maleic ester or a salt of maleic acid.
Claim 6
Dependent Claim
34 words
Method according to claim 1, wherein said polymer, which bears hydroxamic groups, is a copolymer of the hydrocarbon chain with units selected from the group consisting of vinyl, vinyl pyrrolidone, butadiene, styrene and acrylonitrile.
Claim 7
Dependent Claim
15 words
Method according to claim 1, wherein said polymer bears amide groups beside the hydroxamic ones.
Claim 8
Dependent Claim
28 words
Method according to claim 6, wherein said polymer is constituted by a chain of polyacrylamide in which 10 to 90% of amide groups are replaced by hydroxamic groups.
Claim 9
Dependent Claim
24 words
Method according to claim 1, wherein at least one of the oxygene atoms in the hydroxamic function ##STR6## is replaced by a sulfur atom.
Claim 10
Dependent Claim
24 words
Method according to claim 7, wherein at least one of the oxygen atoms in the hydroxamic function ##STR7## is replaces by a sulfur atom.
Claim 11
Dependent Claim
16 words
Method according to claim 7, wherein the molecular mass of the polymer is 500 to 25000.
Claim 12
Dependent Claim
23 words
Method according to claim 1, wherein the concentration of the hydroxamic groups bearing polymer is 0.1×10 -6 to 5×10 -6 macromolecules per liter.
Claim 13
Dependent Claim
31 words
Method according to claim 1, wherein one or two hydrogen atoms in the --NHOH moiety of the hydroxamic group are substituted with C 1 to C 6 alkyles, phenyls or alkylaryls.
Claim 14
Dependent Claim
22 words
Method according to claim 7, wherein the concentration of the polymer in the water treated is 0.5 to 10 mg per liter.
Claim 15
Dependent Claim
22 words
Method according to claim 13, wherein the water to be treated contains about 150 to about 1,540 mg of clay per liter.
Claim 16
Dependent Claim
57 words
Method of impeding the sedimentation of clays in a water containing the same, which consists in dissolving, per liter of the water, 0.5 to 10 mg of a copolymer constituted by polyacrylamide in which 10 to 90% of --CONH 2 groups are replaced by ##STR8## groups, the molecular mass of the copolymer being of 500 to 25000.
Claim 17
Dependent Claim
57 words
Method of impeding the sedimentation of clays in a water containing the same, which consists in dissolving, per liter of the water, 0.5 to 10 mg of a copolymer constituted by polyacrylamide in which 10 to 90% of --CONH 2 groups are replaced by ##STR8## groups, the molecular mass of the copolymer being of 500 to 25000.
Claim 18
Dependent Claim
47 words
Method according to claim 15, wherein the amount of said copolymer is 1 to 5 mg per liter, the copolymer being formed by polyacrylamide in which 30 to 60% of --CONH 2 groups are replaced ##STR9## the molecular mass of the copolymer being about 800 to 2000.
Claim 19
Dependent Claim
20 words
Method according to claim 16, wherein the water to be treated contains 150 to 1,540 mg of clay per liter.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-30 | 1988-04-30 | 1988-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-30 | 1992-04-30 | 1992-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-30 | 1996-04-30 | 1996-10-30 | $7700.00 | Window Closed / Lapsed |