Selective phosphate extraction

Abstract

The invention relates to a process for the production of phosphoric acid, phosphoric acid obtainable by the process, the production of ammonium phosphate salts, and to the use of ammonium salts. A process for the production of phosphoric acid, comprising: i) reacting a phosphorus-containing material with an acid, without organic solvent, thereby forming a reaction mixture comprising phosphoric acid, wherein said acid has a pKa of 3.5 or lower, and ii) extracting phosphoric acid from the reaction mixture by adding organic solvent to the reaction mixture, thereby forming a phosphoric acid solution, wherein 20 wt. % or less of free water is added to the reaction mixture, based on the total weight of the reaction mixture, and the phosphorus-containing material comprises secondary raw material comprising phosphate.

Dependencies are inferred from the claim text.