Preparation of mixed metal oxides by decomposition of carbonate solid solutions having the calcite structure
US4060500A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1976 |
| Grant date | Nov 29, 1977 |
| Priority date | — |
| Expiry date | May 10, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for the preparation of high surface area mixed metal oxides by decomposition of solid solutions of carbonates possessing the calcite structure. Oxide compounds comprising mixtures of Ca, Mn, Fe, Co, Ni, Zn, Cd and Mg can be prepared by this method. For example, CaMnO.sub.3 with a surface area of 11 m.sup.2 /g useful as a battery cathode, has been prepared by the instant method, that is, by decomposition of a CaMn(CO.sub.3).sub.2 precursor. The mixed metal carbonate solid solutions which are used as precursors for the preparation of the mixed metal oxides are themselves prepared by the precipitation from solution of the appropriate metal ions by the addition of an excess of a carbonate ion source (such as (NH.sub.4).sub.2 CO.sub.3). The metal-ion ratio in this solution is adjusted so that the resulting precipitate has the same stoichiometry as the desired oxide. The intimate mixing achieved by using the carbonate precipitation technique allows calcination to metal oxide to be run at lower temperatures for shorter periods of time, thereby achieving higher surface areas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.