US4548718A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treating cyanide-containing effluents
Assignee: JOHANNESBURG CONSOLIDATED INVESTMENT Co Ltd 66 ACACIA ROAD PRIMOSE EAST GERMISTON 1401 TRANSVAAL SA
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Filing: 1983-09-26
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Granted: 1985-10-22
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Expires: 2003-09-26
Abstract
Abstract Effluents from cyanidation operations are treated by contacting the effluent with powdered sulphur and iron to reduce the base metal content and cyanide ion content of the effluents.
Inventors
- 👤 Colin W. A. Muir
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:08
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/70; C02F1/705; C02F2101/00; C02F2101/10; C02F2101/16; C02F2101/18; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/903; Y10S210/904; Y10S210/911; Y10S210/912
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
87 words
A method of treating an effluent containing metal cyanide complexes and free cyanide to reduce the metal and cyanide content thereof including the steps of contacting the effluent with at least about 5 grams of powdered sulphur and at least about 11.5 grams of metallic iron for each 500 ml of effluent, at a pH of at least 8 and at a temperature of between 50° C. and the boiling point of the effluent, and filtering of the effluent to reduce the metal and cyanide content thereof.
Claim 2
Independent Claim
87 words
A method of treating an effluent containing metal cyanide complexes and free cyanide to reduce the metal and cyanide content thereof including the steps of contacting the effluent with at least about 5 grams of powdered sulphur and at least about 11.5 grams of metallic iron for each 500 ml of effluent, at a pH of at least 8 and at a temperature of between 50° C. and the boiling point of the effluent, and filtering of the effluent to reduce the metal and cyanide content thereof.
Claim 3
Dependent Claim
19 words
The method claimed in claim 1 in which the sulphur is less than half by mass of the iron.
References Cited (Backward Citations)
US2194438A
Cited
US3235489A
Cited
JPS4924420A
Cited
US3931007A
Cited
DE2307669A1
Cited
JPS50656A
Cited
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Cited
JPS51108672A
Cited
US4250030A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |