Continuous process for production of ceramic powders with controlled morphology
US5453262A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1992 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Jun 10, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/626
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A continuous process for making a crystalline ceramic powder having a perovskite structure, ABO.sub.3, comprising: PA1 a. preparing a first acidic aqueous solution containing one or more elements that are insoluble precursor elements capable of forming the perovskite structure; PA1 b. preparing a second basic solution containing a sufficient concentration of hydroxide to precipitate the elements in step (a); PA1 c. mixing the first acidic solution with the second basic solution to precipitate a substantially pure mixture of hydroxides; PA1 d. washing the precipitate to remove hydroxide and salt impurities; PA1 e. forming a slurry of oxides or hydroxides of one or more of the elements that are soluble precursor elements capable of forming in the perovskite structure, and heating the slurry to a temperature sufficient to dissolve the soluble oxides or hydroxides of the soluble precursor elements; PA1 f. redispersing the washed precipitate and heating to the temperature of the soluble oxides or hydroxides of step (e); PA1 g. mixing solubilized oxides or hydroxides of step (e) with the heated slurry of step (f); PA1 h. prereacting the third aqueous slurry at temperature, pressure, conc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.