Manufacture of phosphoric acid
US3984525A · kind A · utility
4Cited by
1References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1974 |
| Grant date | Oct 5, 1976 |
| Priority date | — |
| Expiry date | Mar 25, 1994 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/22
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Production of phosphoric acid by the wet process and by-product calcium sulphate hemihydrate. Sulphuric acid reacts with phosphate rock in such conditions that gypsum is precipitated, the resulting slurry is transferred to a second vessel in which the conditions are such that the gypsum recrystallises to calcium sulphate hemihydrate. Calcium sulphate hemihydrate so produced may be converted to cement and sulphuric acid by a process analogous to the anhydrite process for production of sulphuric acid. The phosphoric acid produced may be desulphated in a process integrated with the phosphoric production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.