Process for producing unsintered cristobalite silica
US4853198A · kind A · utility
19Cited by
3References
9Claims
0Family size
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Key dates
| Filing date | Mar 17, 1988 |
| Grant date | Aug 1, 1989 |
| Priority date | — |
| Expiry date | Mar 17, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C1/022
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
There is disclosed a process for producing unsintered cristobalite silica by heating an amorphous silica in the presence of an alkali component, which comprises heating an amorphous silica having a specific surface area (measured according to BET method) of 50 m.sup.2 /g or more at a temperature in the range of 1000.degree. to 1300.degree. C., in the presence of an alkali metal element in a concentration of 5 to 600 ppm to said silica to change it partially or completely into cristobalite and then heating at a temperature of exceeding 1300.degree. C. to eliminate alkali.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.