Process for the preparation of substantially crystalline calcium sodium metaphosphate
US4725369A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1986 |
| Grant date | Feb 16, 1988 |
| Priority date | — |
| Expiry date | Nov 5, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/45
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Substantially crystalline calcium sodium metaphosphate having a degree of crystallinity from about 60% to about 75% as determined from density and differential thermal analysis measurements is prepared by (a) bringing together in water source materials for CaO, Na.sub.2 O, and P.sub.2 O.sub.5 in proportions sufficient to provide a CaO/Na.sub.2 O/P.sub.2 O.sub.5 mol percent ratio on a dry basis of about 29.0-34.0/16.0-18.0/50.0-53.0 and form a wet mix slurry containing a solid phase and an aqueous liquid phase and (b) heating the wet mix slurry at a temperature and for a time sufficient to remove the aqueous liquid phase and calcine the resulting solid phase to form the substantially crystalline calcium sodium metaphosphate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.