Method for preparing iron oxides
US6790274B2 · kind B2 · utility
4Cited by
4References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2003 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Mar 12, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/13
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Highly pure iron oxides are prepared by reaction of metallic iron, in the form of microspheroidal particles or of scraps or cuttings, with an agitated aqueous solution of a mono- or polycarboxylic acid with a pKa of 0.5 to 6 relative to the first carboxyl and capable of decomposing, by heating in air at 200 to 350° C., to carbon dioxide and water, using 0.03 to 1.5 moles of acid per g-atoms of iron, a water/iron weight ration of 1 to 20, and by oxidation of the ferrous carboxilate to ferric salt, with an agent selected from oxygen, mixtures containing oxygen, hydrogen peroxide, organic peroxides and hydroperoxides.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.