Recovery of non-ferrous metals by thermal treatment of solutions containing non-ferrous and iron sulphates
US4415540A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 1982 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | Feb 8, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S423/16
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The specification discloses a method for recovering non-ferrous metals such as zinc or copper iron from their concentrates, ores or any other metal containing materials into a solution containing these non-ferrous metals as sulphates and a minimal amount of dissolved iron. The resultant solution is suited without or with minimum pre-purification treatment for conventional electrowinning processes to recover such non-ferrous metals with less difficulties than the previous methods involving complex iron-removal processing. There is disclosed a method for recovering at least one non-ferrous metal soluble in sulphuric acid from a strong sulphuric acid solution containing said metal and iron as sulphates, said method comprising the following consecutive steps: PA0 subjecting said solution in a sub-divided form to thermal decomposition in a fluidized bed reactor at a temperature of from 600.degree. to 750.degree. C. with 20-150% excess air for an average retention time of 1-12 hours to obtain calcine containing ferric oxide and the sulphate of said non-ferrous metal; PA0 leaching said non-ferrous metal sulphate out from said calcine with water or dilute sulphuric acid solutions; PA0 sepa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.