Method of recovering metal from metalliferous waste
US3966569A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1975 |
| Grant date | Jun 29, 1976 |
| Priority date | — |
| Expiry date | Feb 25, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S423/14
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Metal can be recovered from metal-containing waste by means of liquid extraction processes. The waste is leached with sulphuric acid. The resulting metal sulphate solution is contacted with an organic solution of a reagent, so as to extract iron and zinc to the organic solution. The organic solution is washed with sulphuric acid in two steps, viz. with weaker acid in the first step, so as to transfer zinc to the washing solution, and with stronger acid in the second step, so as to transfer iron to the washing solution. Zinc and iron have now been separated, and are recovered from the washing solutions in known ways, for example by crystallization. If the waste contains other metals, in addition to iron and zinc, additional selective liquid extraction processes are added, before or after the iron-zinc-extraction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.