US4662948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
On-site removal of PCB and dioxins from soils
Assignee: Electric Power Research Institute
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Filing: 1984-11-28
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Granted: 1987-05-05
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Expires: 2004-11-28
Abstract
Abstract A method is provided for removing PCBs and/or dioxins from solids contaminated therewith comprising contacting such solids with a halogenated hydrocarbon and a polar solvent.
Inventors
- 👤 Leo Weitzman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:52
CPC Classifications
B; B09; B09C; B09C1/00; B09C1/02; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/908; Y10S210/909
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
75 words
A method for removing polychlorinated biphenyls and dioxins from soil, landfill, gravel, sand, clay or a mixture thereof, contaminated with said biphenyls and/or said dioxins, comprising the steps of (a) contacting said soil, landfill, gravel, sand, clay or a mixture thereof with a liquid consisting essentially of 99-70% by volume halogenated hydrocarbon and 1-30% by volume of a polar solvent selected from the group consisting of lower alcohols and ketones; and (b) separating said liquid.
Claim 2
Independent Claim
75 words
A method for removing polychlorinated biphenyls and dioxins from soil, landfill, gravel, sand, clay or a mixture thereof, contaminated with said biphenyls and/or said dioxins, comprising the steps of (a) contacting said soil, landfill, gravel, sand, clay or a mixture thereof with a liquid consisting essentially of 99-70% by volume halogenated hydrocarbon and 1-30% by volume of a polar solvent selected from the group consisting of lower alcohols and ketones; and (b) separating said liquid.
Claim 3
Dependent Claim
13 words
A method according to claim 1 wherein said halogenated hydrocarbon comprises a chlorofluorocarbon.
Claim 4
Dependent Claim
12 words
A method according to claim 1 wherein said polar solvent comprises methanol.
Claim 5
Dependent Claim
14 words
A method according to claim 3 wherein said halogenated hydrocarbon consists essentially of 1,2-dichloro-1,2-difluroethane.
References Cited (Backward Citations)
US2999816A
Cited
US3477952A
Cited
US3734774A
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US3945932A
Cited
US4425949A
Cited
US4483717A
Cited
US4483716A
Cited
US4447541A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-04 | 1990-11-03 | 1991-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-04 | 1994-11-03 | 1995-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-04 | 1998-11-03 | 1999-05-05 | $7700.00 | Window Closed / Lapsed |