Clarification of black phosphoric acid with phosphoric acid rinse water
AssigneeMobil Oil Corporation
InventorsMark D. LaVanture, George L. Walker
Life of this patent
Estimating the term…
Abstract
This invention provides a process for clarifying black wet process phosphoric acid that comprises admixing said black phosphoric acid with phosphoric acid rinse water in a weight ratio of rinse water to black acid between about 0.5 and about 5, letting the resultant mixture stand thereby obtaining settled material and supernatant clarified black phosphoric acid, and, when said weight ratio is below about 1 to 1.5, depending on the quality of the black acid being clarified, separating said clarified black phosphoric acid from said settled material.
Claims6
A process for clarifying black wet process phosphoric acid that comprises admixing said black phosphoric acid with phosphoric acid rinse water in a weight ratio of rinse water to black phosphoric acid between about 0.5 and about 5 and letting the resultant mixture stand, thereby obtaining settled material and supernatant clarified black phosphoric acid, said phosphoric acid rinse water being the water collected from aluminum bright dipping water rinsing and containing, by weight, about 10-45% P.sub.2 O.sub.5 and impurities including about 0.5-3% HNO.sub.3 and about 0.2-3% Al.
Dependencies are inferred from the claim text.