US3901802A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extraction of heavy metals from wastes
Assignee: Belgonucleaire SA
•
Filing: 1973-03-26
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Granted: 1975-08-26
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Expires: 1993-03-26
Abstract
Abstract A method for extracting heavy metal ions from wastes including contacting the wastes with a mixed salt consisting of iron sulfide and barium sulfate containing a surplus of sulfide ions.
Inventors
- 👤 Karel Peeters
- 👤 De Voorde Norbert Van
- 👤 Paul Dejonghe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:14
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5236; B; B01; B01J; B01J20/00; C02F1/28; C02F1/281
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
PROCESS FOR EXTRACTING SMALL QUANTITIES OF HEAVY METAL IONS SELECTED FROM THE GROUP CONSISTING OF MERCURY, COPPER, LEAD, ZINC, AND CADMIUM FROM WATER, WHEREIN THE WATER IS BROUGHT INTO CONTACT WITH AN INSOLUBLE MIXED SALT OF IRON SULFIDE AND BARIUM SULPHATE, CONTAINING A SURPLUS OF SULFIDE IONS, WHEREIN THE MOLAR RATION OF IRON/BARIUM IS BETWEEN 1 AND 3.
Claim 2
Dependent Claim
58 words
PROCESS FOR EXTRACTING SMALL QUANTITIES OF HEAVY METAL IONS SELECTED FROM THE GROUP CONSISTING OF MERCURY, COPPER, LEAD, ZINC, AND CADMIUM FROM WATER, WHEREIN THE WATER IS BROUGHT INTO CONTACT WITH AN INSOLUBLE MIXED SALT OF IRON SULFIDE AND BARIUM SULPHATE, CONTAINING A SURPLUS OF SULFIDE IONS, WHEREIN THE MOLAR RATION OF IRON/BARIUM IS BETWEEN 1 AND 3.
Claim 3
Dependent Claim
14 words
Process according to claim 1, wherein the mixed salt also comprises a calcium salt.
Claim 4
Dependent Claim
15 words
Process according to claim 2, wherein the molar ratio iron/calcium is between 2 and 0.5.
Claim 5
Dependent Claim
16 words
Process according to claim 3, wherein the molar ratio of sulfide/iron is between 4:1 and 2.
Claim 6
Dependent Claim
16 words
Process according to claim 4, wherein the molar ratio of iron/barium is between 2 and 2.5.
Claim 7
Dependent Claim
12 words
Process according to claim 2, wherein the calcium salt is calcium hydroxide.
Claim 8
Dependent Claim
27 words
Process according to claim 6 wherein the molar ratio of iron/calcium is between 2 and 0.5 and the molar ratio of sulfide/iron is between 4:1 and 2:1.
Claim 9
Dependent Claim
16 words
Process according to claim 7 wherein the molal ratio of iron/barium is between 2 and 2.5.
Claim 10
Dependent Claim
16 words
Process according to claim 1, wherein the molar ratio of iron/barium is between 2 and 2.5.
Claim 11
Dependent Claim
15 words
Process according to claim 1, wherein the molar ratio sulfide/iron is between 4:1 and 2:1.
References Cited (Backward Citations)
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Cited
US3408291A
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US3575854A
Cited
US3674428A
Cited
US3716484A
Cited
US3740331A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |