Method for continuous synthesis of metal oxide powders
US9126833B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 2014 |
| Grant date | Sep 8, 2015 |
| Priority date | — |
| Expiry date | Jun 5, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/62
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for the rapid and continuous production of crystalline mixed-metal oxides from a precursor solution comprised of a polymerizing agent, chelated metal ions, and a solvent. The method discharges solution droplets of less than 500 μm diameter using an atomizing or spray-type process into a reactor having multiple temperature zones. Rapid evaporation occurs in a first zone, followed by mixed-metal organic foam formation in a second zone, followed by amorphous and partially crystalline oxide precursor formation in a third zone, followed by formation of the substantially crystalline mixed-metal oxide in a fourth zone. The method operates in a continuous rather than batch manner and the use of small droplets as the starting material for the temperature-based process allows relatively high temperature processing. In a particular embodiment, the first zone operates at 100-300° C., the second zone operates at 300-700° C., and the third operates at 700-1000° C., and fourth zone operates at at least 700° C. The resulting crystalline mixed-metal oxides display a high degree of crystallinity and sphericity with typical diameters on the order of 50 μm or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.