Removal of heavy metals from waste water
US4731187A · kind A · utility
63Cited by
2References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1986 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Jul 22, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/914
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A heavy metal can be removed from waste water, in which the metal is contained as ions, by adding to the waste water a metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide to form a metal ion containing floc. The resulting floc is then removed from the waste water by filtration. The metal scavenger contains at least one carbodithio group and/or at least one carbodithioate salt group as N-substituents per molecule.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.