Purification of wet process phosphoric acid

摘要

Wet process phosphoric acid is heated by passing alternating current through the acid, preferably in carbon apparatus to concentrations above 76% P2O5 and preferably temperatures above 500 DEG C. to remove sulphate and fluoride and convert organic and basic impurities into a filterable precipitate; the acid is separated from the precipitate preferably after dilution with water to provide a high purity crystallizable product.