Treatment system for alkaline or acidic solution containing heavy metals
US5308501A · kind A · utility
Inventor
Key dates
| Filing date | Apr 2, 1993 |
| Grant date | May 3, 1994 |
| Priority date | — |
| Expiry date | Apr 2, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/913
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
There is disclosed a method of treating a solution, e.g., an alkaline or acidic solution, containing heavy metals ions therein. With respect to alkaline solutions, the method includes providing a body of the solution; contacting the body with a material such as carbon dioxide to change the pH, e.g., to lower the pH to a pH in the range of 9 to 10.5; then treating the solution to further change the pH and cause precipitation of hydroxides, including chromium hydroxide; and separating the hydroxide precipitates from the solution to provide a substantially neutral solution having a reduced amount of chromium ions, for example, contained therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.