| 摘要 |
Extraction battery fouling is reduced in the solvent extraction purification of crude phosphoric acid by performing the steps of: (a) extracting crude phosphoric acid with solvent in a main extraction battery without the addition of sulfuric acid; (b) acidulating the raffinate from step (a) with at least a precipitate-forming amount of sulfuric acid; (c) aging the precipitate of step (b) for at least 15 minutes, and separating the precipitate from the acidulated raffinate; (d) extracting with organic solvent the essentially precipitate-free raffinate of step (c) in a secondary extraction battery.
|
