Colloidal dispersion of particles of a rare-earth vanadate or phosphovanadate
US7674834B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 2007 |
| Grant date | Mar 9, 2010 |
| Priority date | — |
| Expiry date | Aug 18, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/64
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention concerns a colloidal dispersion of a vanadate or a phosphovanadate of at least a rare earth comprising either a complex-forming agent having a pK higher than 2.5, or an anion of a monovalent acid, soluble in water and having a pKa ranging between 2.5 and 5. The dispersion is obtained by contacting a colloidal dispersion or a dispersion of initial complexes comprising at least a rare earth compound and at least a complex-forming agent or an anion of said monovalent acid and whereof the pH has been adjusted to a value of at least 7, with vanadate ions, then, in adjusting the pH of the resulting medium to a value of at least 9 and heating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.