US4363749A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water clarification coagulant/adsorbent
Assignee: Commonwealth Scientific and Industrial Research Organisation
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Filing: 1981-02-04
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Granted: 1982-12-14
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Expires: 2001-02-04
Abstract
Abstract A particulate coagulant/adsorbent for removing suspended impurities and colored substances from water by coagulation comprises a finely divided particulate mineral or clay material, the individual particles of which have been treated to produce a thin hydroxylated surface layer having a positive zeta potential at the adsorption pH. A process and an apparatus for water treatment utilizing the coagulant/adsorbent and providing for regeneration and recycling thereof are also described.
Inventors
- 👤 Donald E. Weiss
- 👤 Luis O. Kolarik
- 👤 Anthony J. Priestley
- 👤 Nevil J. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:34
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5227; B; B01; B01J; B01J20/00; B01J20/02; B01J20/0203; B01J20/0225; B01J20/0229; B01J20/024; B01J20/0244; B01J20/04; B01J20/043; B01J20/045; B01J20/06; B01J20/08; B01J20/10; B01J20/12; B01J20/22; B01J20/26; B01J20/262; B01J20/28; B01J20/28002; B01J20/28004; B01J20/28009; B01J20/28011; B01J20/28014; B01J20/28047; B01J20/30; B01J20/3021; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3231; B01J20/3234; B01J20/3236; B01J20/34; B01J20/3433; B01J20/345; B01J20/3475; C02F1/28; C02F1/281; C02F1/48; C02F1/488; C02F1/5236; C02F1/54; B01J2220/00; B01J2220/40; B01J2220/46; B01J2220/48; B01J2220/4806; B01J2220/50; B01J2220/56
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
74 words
A particulate coagulant/adsorbent suitable for removing suspended impurities and coloured substances from water by coagulation which comprises a finely divided particulate mineral or clay material, the individual particles of which have a particle size of 10 microns or less and have been treated to produce a thin hydroxylated surface layer derived from the substance of the particulate mineral or clay material and having a positive zeta potential at the adsorption pH (as hereinbefore defined).
Claim 2
Dependent Claim
74 words
A particulate coagulant/adsorbent suitable for removing suspended impurities and coloured substances from water by coagulation which comprises a finely divided particulate mineral or clay material, the individual particles of which have a particle size of 10 microns or less and have been treated to produce a thin hydroxylated surface layer derived from the substance of the particulate mineral or clay material and having a positive zeta potential at the adsorption pH (as hereinbefore defined).
Claim 3
Dependent Claim
19 words
A coagulant/adsorbent as claimed in claim 1, wherein the particulate mineral or clay material is an oxide or silicate.
Claim 4
Dependent Claim
20 words
A coagulant/adsorbent as claimed in claim 1, wherein the particulate mineral or clay material is a magnetic or magnetisable material.
Claim 5
Dependent Claim
27 words
A coagulant/adsorbent as claimed in claim 1, wherein the particulate mineral or clay material is selected from the group consisting of gamma iron oxide, magnetite and ferrites.
Claim 6
Dependent Claim
34 words
A method for preparing the coagulant/adsorbent claimed in claim 1, which consists essentially of suspending the particulate mineral or clay material in an alkali solution for a period sufficient to form the hydroxylated layer.
Claim 7
Dependent Claim
49 words
The method for preparing the coagulant/adsorbent as claimed in claim 1, which consists essentially of suspending the particulate mineral or clay material in a 0.05 to 0.1 N sodium hydroxide solution for a period of from 5 to 10 minutes at a temperature of from 20° to 60° C.
Claim 8
Dependent Claim
23 words
A particulate coagulant/adsorbent according to claim 1 consisting of said finely divided particulate mineral or clay material with said thin hydroxylated surface layer.
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) | 1985-12-13 | 1986-06-14 | 1986-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-13 | 1990-06-14 | 1990-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-13 | 1994-06-14 | 1994-12-14 | $7700.00 | Window Closed / Lapsed |