Process for the purification of phosphoric acid by solvent extraction

摘要

The invention relates to a process for the purification of phosphoric acid by solvent extraction. This process is of the type in which an aqueous solution of impure phosphoric acid is brought into contact with an organic solvent which has little or no miscibility with water and which extracts the purified phosphoric acid and the phases obtained are separated, and it is characterised in that the organic solvent comprises at least one compound chosen from the group of diesters of a phosphinic acid, esters of a phosphinic acid and phosphine oxides, and in that the solvent is brought into contact with the aqueous solution in the presence of sulphuric acid.