Process for removing sulfate ions from extracted phosphoric acid with a barium compound
US4070443A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1976 |
| Grant date | Jan 24, 1978 |
| Priority date | — |
| Expiry date | Jun 22, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/234
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for removing sulfate ions from extracted phosphoric acid which is substantially free of metallic ion impurities and which has been prepared by extracting wet process phosphoric acid with an organic solvent which comprises: A. adjusting the extracted phosphoric acid concentration to a concentration greater than 70%; B. adding an amount of a barium compound which is less than the stoichiometric equivalent amount of barium relative to the amount of dissolved sulfate ion to form barium sulfate crystals; and C. separating said barium sulfate from the resulting slurry at a temperature less than 80.degree. C and recovering purified, extracted phosphoric acid; Wherein the amount of barium compound added is such that said purified extracted phosphoric acid contains at least 5 ppm of sulfate ions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.