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US4394356A
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Recuperation of cyanides from rinsing solutions of cyanidric processes for eletrodeposition of metals
Assignee: Individual
•
Filing: 1980-01-18
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Granted: 1983-07-19
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Expires: 2000-01-18
Abstract
Abstract Process for the recuperation of an insoluble salt of a metal from the rinsing solution of an electrodeposition of the metal.
Inventors
- 👤 Michael F. Peuser
- 👤 Jose B. Bartolo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:39
CPC Classifications
C; C01; C01C; C01C3/00; C01C3/08; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/903; Y10S210/904; Y10S210/911; Y10S210/912
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
116 words
A process for recuperation of a cyanide from a rinsing solution of a cyanidric process for electrodeposition of copper, the solution containing a soluble complex cyanide of an alkali metal and copper, comprising adding to the solution a soluble simple salt of bivalent copper reacting with said complex cyanide and any free cyanide ions in said solution to form and precipitate an insoluble cyanide of copper, and separating said precipitant for reuse, said precipitation, being conducted without using hydrochloric acid by adding sodium bisulfite to the solution to reduce the pH of the solution to between 1.5 and 4.0 and the copper ion of the simple salt to a cuprous state for precipitating insoluble cuprous cyanide.
Claim 2
Dependent Claim
116 words
A process for recuperation of a cyanide from a rinsing solution of a cyanidric process for electrodeposition of copper, the solution containing a soluble complex cyanide of an alkali metal and copper, comprising adding to the solution a soluble simple salt of bivalent copper reacting with said complex cyanide and any free cyanide ions in said solution to form and precipitate an insoluble cyanide of copper, and separating said precipitant for reuse, said precipitation, being conducted without using hydrochloric acid by adding sodium bisulfite to the solution to reduce the pH of the solution to between 1.5 and 4.0 and the copper ion of the simple salt to a cuprous state for precipitating insoluble cuprous cyanide.
Claim 3
Dependent Claim
19 words
A process according to claim 1, wherein the added salt is a salt of copper and a strong acid.
Claim 4
Dependent Claim
117 words
A process for recuperation of a cyanide from a rinsing solution of a cyanidric process for electrodeposition of cadmium, the solution containing a soluble complex cyanide of an alkali metal and cadmium, comprising conducting the process in two stages, in a first whereof the solution is diluted to a cadmium content below 17 g/l, a soluble salt of zinc and a strong acid is added to the diluted solution to precipitate insoluble zinc cyanide, and the precipitate is separated from the solution, and in the second stage adding to the solution from the first stage an alkali compound reacting with cadmium ions in the solution to form and precipitate an insoluble cadmium salt, and separating the precipitate.
Claim 5
Dependent Claim
117 words
A process for recuperation of a cyanide from a rinsing solution of a cyanidric process for electrodeposition of cadmium, the solution containing a soluble complex cyanide of an alkali metal and cadmium, comprising conducting the process in two stages, in a first whereof the solution is diluted to a cadmium content below 17 g/l, a soluble salt of zinc and a strong acid is added to the diluted solution to precipitate insoluble zinc cyanide, and the precipitate is separated from the solution, and in the second stage adding to the solution from the first stage an alkali compound reacting with cadmium ions in the solution to form and precipitate an insoluble cadmium salt, and separating the precipitate.
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) | 1986-07-18 | 1987-01-17 | 1987-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-18 | 1991-01-17 | 1991-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-18 | 1995-01-17 | 1995-07-19 | $7700.00 | Window Closed / Lapsed |