Process for the production of phosphoric acid and hydrogen fluoride from phosphate rock and fluosilicic acid

摘要

A process for the preparation of phosphoric acid from a feedstock of phosphate rock and fluosilicic acid is described, which process comprises reacting the phosphate rock and the fluosilicic acid together to produce a reaction slurry of phosphoric acid, calcium fluoride, silicon dioxide and undigested phosphate rock and wherein an excess stoichiometric amount of calcium to fluorine is initially present in the slurry. The phosphoric acid and calcium fluoride is then separated and the phosphoric acid is finally recovered.