Production of phosphoric acid
Abstract
Abstract Phosphate rock is reacted with hydrochloric acid in the presence of a water-soluble sodium compound to produce an aqueous acidulate containing phosphoric acid. The aqueous acidulate is extracted with a homogeneous organic liquid extractant comprising a liquid hydrocarbon and a low molecular weight, acidulateimmiscible alcohol to produce an organic solution of phosphoric acid. The organic solution of phosphoric acid is extracted with water and the resulting extract is concentrated to produce phosphoric acid which is low in calcium chloride content. Preferably, the organic solution of phosphoric acid is purified by extraction with aqueous phosphoric acid to remove calcium prior to extraction with water. The product phosphoric acid contains only 0.05-0.5 part by weight of calcium per 100 parts by weight of phosphoric acid, measured as P2O5, and is particularly useful in production of stable fertilizer solutions.
Inventors
- 👤 W Klingelhoefer
- 👤 J Sansing
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |