Magnesia granule coated with silica or forsterite
US4977024A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1988 |
| Grant date | Dec 11, 1990 |
| Priority date | — |
| Expiry date | Jun 2, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2993
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A magnesia granule having a surface covered with a continuous and uniform coating of silica or forsterite, and suitable for use as a filler. The magnesia granule is prepared by a process comprising granulating a magnesia powder into a spherical shape, heat treating the granular particles at a temperature in a range of from 1400.degree. C. to 1700.degree. C. for not more than 1 hour, and then subjecting the particles to gas-solid phase mixing with a heated vapor of an organic silicate compound in a fluidized bed reactor to cover the surface of the granular magnesia particles with a continuous and uniform coating of silica, or a process comprising granulating a magnesia powder of particles coated with a silica layer into a spherical shape, and then heat treating the granular particles at a temperature in a range of from 1400.degree. C. to 1700.degree. C. for not more than 1 hour to cover the surface of the granular particles with a continuous and uniform coating or forsterite.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.