Extraction and purification of silver from sulfates
US3996046A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1975 |
| Grant date | Dec 7, 1976 |
| Priority date | — |
| Expiry date | Jul 25, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22B11/04
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method is provided for extracting silver from a silver sulfate-bearing substance, such as oxide materials, metal or metal sulfate mixtures containing silver sulfate which comprises subjecting said substance to aqueous leaching to remove soluble salts therefrom and leave a residue, taking the residue containing silver sulfate and other insoluble materials, such as insoluble salts, and forming a slurry with an aqueous solution of a metal sulfate, such as calcium nitrate, the amount of calcium nitrate being at least sufficient to effect metathetical exchange with the silver sulfate and form a silver nitrate solution containing substantially the silver originally present in the silver-sulfate bearing substance, and separating the silver nitrate solution from the residue remaining, and then purifying said solution, the silver being thereafter recovered from the silver nitrate solution by hydrolytic precipitation, electrowinning or other suitable means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.