US4729795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stable slurries comprising powdered activated carbon
Assignee: Veolia WTS USA Inc
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Filing: 1986-07-25
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Granted: 1988-03-08
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Expires: 2006-07-25
Abstract
Abstract Stable, thixotropic slurries comprising wood-based powdered activated carbon and an effective amount of a polysaccharide suspending agent are disclosed. Such slurries are useful as water clarification and coagulation aids.
Inventors
- 👤 Bruce K. Fillipo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:34
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/283; C02F1/52; C02F1/54
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
82 words
Slurry composition comprising powdered activated carbon prepared by the destructive distillation of a wood precursor, sodium carboxymethylcellulose, and hectorite clay, wherein, based on the total weight of said slurry, said powdered activated carbon being present in an amount of from about 1% to about 50 wt %, said sodium carboxymethylcellulose being present in an amount of from about 0.25% to about 5 wt %, and said hectorite clay being present in an amount of from about 0.25% to about 5 wt %.
Claim 2
Dependent Claim
82 words
Slurry composition comprising powdered activated carbon prepared by the destructive distillation of a wood precursor, sodium carboxymethylcellulose, and hectorite clay, wherein, based on the total weight of said slurry, said powdered activated carbon being present in an amount of from about 1% to about 50 wt %, said sodium carboxymethylcellulose being present in an amount of from about 0.25% to about 5 wt %, and said hectorite clay being present in an amount of from about 0.25% to about 5 wt %.
Claim 3
Dependent Claim
45 words
Composition as recited in claim 1 wherein said powdered activated carbon is present in an amount of about 25 wt %, said sodium carboxymethylcellulose being present in an amount of about 0.5 wt % and said hectorite being present in an amount of about 0.25%.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-08 | 1991-09-07 | 1992-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-08 | 1995-09-07 | 1996-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-08 | 1999-09-07 | 2000-03-08 | $7700.00 | Window Closed / Lapsed |