Selective removal of phosphates and chromates from contaminated water by ion exchange
US6136199A · kind A · utility
18Cited by
12References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1998 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Dec 7, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/913
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Phosphates and chromates are selectively removed from contaminated water by a new class of sorbent, referred to as a Polymeric Ligand Exchanger (PLE). The exchanger bed comprising a styrene-divinylbenzene or polymethacrylate matrix having an electrically neutral chelating functional group with nitrogen or oxygen donor atoms, and a Lewis-acid type metal cation, such as copper, bonded to the chelating functional group in a manner that the positive charges of the metal cation are not neutralized. PLEs are very selective toward phosphates and chromates, chemically stable, and also amenable to efficient regeneration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.