Method for preparing iron oxides
US7442362B2 · kind B2 · utility
1Cited by
7References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2004 |
| Grant date | Oct 28, 2008 |
| Priority date | — |
| Expiry date | Feb 7, 2026 |
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.