Patent US3968037A successfully refreshed from Google Patents.
US3968037A
Expired / Lapsed
US
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Emulsion polymerization of cationic monomers
Assignee: Calgon Corp
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Filing: 1974-06-17
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Granted: 1976-07-06
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Expires: 1994-06-17
Abstract
Abstract Cationic monomers homopolymerized and copolymerized in water-in-oil emulsion systems with crosslinking and branching agents have surprisingly high effectiveness as flocculants and for the treatment of activated sewage sludge.
Inventors
- 👤 Janice Elaine Morgan
- 👤 Jerry Emile Boothe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:21
CPC Classifications
C; C08; C08F; C08F226/00; C08F226/02; C02; C02F; C02F1/00; C02F1/52; C02F1/54; C08F20/00; C08F20/02; C08F20/52; C08F20/54; C08F20/60; C08F36/00; C08F36/02; C08F36/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
184 words
A method of releasing water from activated sewage sludge which comprises steps of adding to the sludge from about 0.1 ppm to about 20 ppm of a cationic polymer prepared by forming an aqueous solution of from about 5% to about 95% by weight dimethyl diallyl ammonium chloride and about 0.005 to about 5 mole %, based on the moles of dimethyl diallyl ammonium chloride of a copolymerizable, polyunsaturated cross-linking monomer selected from the group consisting of methylenebisacrylamide, methyl triallyl ammonium chloride and tetraallyl ammonium chloride, preparing a water-in-oil emulsion of said aqueous solution in a water insoluble liquid containing a surfactant, said water insoluble liquid being about 25% to about 90% by weight of the total emulsion and said surfactant being 0.5 percent to 10 percent by weight of the total emulsion, and heating the emulsion to a temperature sufficient to essentially completely polymerize the monomers in the presence of a free radical polymerization initiator, said free radical polymerization initiator being present in amounts from 10.sup. -7 to 10.sup. -1 mole per mole of dimethyl diallyl ammonium chloride, and filtering the sludge-polymer mixture.
Claim 2
Independent Claim
184 words
A method of releasing water from activated sewage sludge which comprises steps of adding to the sludge from about 0.1 ppm to about 20 ppm of a cationic polymer prepared by forming an aqueous solution of from about 5% to about 95% by weight dimethyl diallyl ammonium chloride and about 0.005 to about 5 mole %, based on the moles of dimethyl diallyl ammonium chloride of a copolymerizable, polyunsaturated cross-linking monomer selected from the group consisting of methylenebisacrylamide, methyl triallyl ammonium chloride and tetraallyl ammonium chloride, preparing a water-in-oil emulsion of said aqueous solution in a water insoluble liquid containing a surfactant, said water insoluble liquid being about 25% to about 90% by weight of the total emulsion and said surfactant being 0.5 percent to 10 percent by weight of the total emulsion, and heating the emulsion to a temperature sufficient to essentially completely polymerize the monomers in the presence of a free radical polymerization initiator, said free radical polymerization initiator being present in amounts from 10.sup. -7 to 10.sup. -1 mole per mole of dimethyl diallyl ammonium chloride, and filtering the sludge-polymer mixture.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-06 | 1980-01-05 | 1980-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-06 | 1984-01-05 | 1984-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-06 | 1988-01-05 | 1988-07-06 | $7700.00 | Window Closed / Lapsed |