Process for treating chromate waste liquid
US6846416B2 · kind B2 · utility
6Cited by
14References
32Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2001 |
| Grant date | Jan 25, 2005 |
| Priority date | — |
| Expiry date | Sep 30, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/913
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The invention relates to a process for treating a chromate waste liquid containing an organic acid component. This process includes (a) adding a chromium precipitation accelerating agent containing at least one of a calcium component and a magnesium component, to the chromate waste liquid; and (b) adjusting the chromate waste liquid to having a first pH of 9 or higher, thereby precipitating a chromium component from the chromate waste liquid and thereby reducing a concentration of a dissolved chromium component of the chromate waste liquid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.