Removal of selenium from acidic copper/nickel solutions
US4374808A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1982 |
| Grant date | Feb 22, 1983 |
| Priority date | — |
| Expiry date | Jun 24, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Selenium (IV) and selenium (VI) are removed from acidic copper-nickel sulphate solutions in a two-stage process by adjusting and maintaining the sulphuric acid content of the solution in a range of 10 to 50 g/L and, in a first stage, contacting the solution with sulphur dioxide or a sulphite-containing solution at an elevated temperature in the range of about 140.degree. to 175.degree. C. and, in a second stage, maintaining the said solution at an elevated temperature in the range of about 140.degree. to 200.degree. C. and pressure within the range of about 400 to 1750 kPa in an essentially oxygen-free atmosphere for a sufficient retention time to reduce and precipitate selenium (VI) as cuprous selenide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.