Process for recovery of silver from spent, waste, acidic processing fluids
US4740244A · kind A · utility
14Cited by
7References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 31, 1986 |
| Grant date | Apr 26, 1988 |
| Priority date | — |
| Expiry date | Oct 31, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Process for recovery of silver from spent, waste acidic silver halide photographic processing fluid, e.g., fixer solution, comprising passing the fluid through finely divided iron, e.g., steel wool, contained in a vessel in the presence of a metal salt of copper or cadmium, e.g., copper(II)sulfate, copper chloride dihydrate, cadmium sulfate, etc. The ratio of iron to metal salt is 25 to 1 to 4 to 1. An apparatus for recovery of silver is also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.