Preparation of sodium orthophosphate mixtures
US4224294A · kind A · utility
3Cited by
5References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 15, 1979 |
| Grant date | Sep 23, 1980 |
| Priority date | — |
| Expiry date | Jan 15, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/412
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A mixture of disodium and monosodium orthophosphate in a 2:1 mole ratio is prepared by sequentially reacting phosphoric acid with monohydrate process soda ash and caustic soda in a semi-solid reaction medium. Milled monohydrate process soda ash is contacted in less than stoichiometric proportions with phosphoric acid and the resultant orthophosphate containing reaction mixture is brought to a sodium to phosphorus mole ratio of about 1.67:1 by subsequent reaction with caustic soda. The final reaction product of mixed disodium and monosodium orthophosphate is suitable feedstock for conversion to sodium tripolyphosphate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.