Hybrid anion exchanger for selective removal of contaminating ligands from fluids and method of manufacture thereof
US7291578B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2004 |
| Grant date | Nov 6, 2007 |
| Priority date | — |
| Expiry date | Dec 24, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2103/06
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
Polymeric anion exchangers are used as host materials in which hydrated Fe(III) Oxides (HFO) are irreversibly dispersed within the exchanger beads. Since the anion exchangers have positively charged quaternary ammonium functional groups, anionic ligands such as arsenates, chromates, oxalates, phosphates, phthalates can permeate in and out of the gel phase and are not subjected to the Donnan exclusion effect. Consequently, anion exchanger-supported HFO micro particles exhibit significantly greater capacity to remove arsenic and other ligands in comparison with cation exchanger supports. Loading of HFO particles is carried out by preliminary loading of the anion exchange resin with an oxidizing anion such as MnO4− or OCl−, followed by passage of a Ferrous Sulfate solution through the resin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.