METHOD OF PRODUCING CONCENTRATED PHOSPHORIC ACID

Monocalcium phosphate, advantageously in the form of single superphosphate or triple superphosphate, is mixed with sulfuric acid or ammonium bisulfate and methanol. The monocalcium phosphate and the sulfuric acid or ammonium bisulfate react to form phosphoric acid and a precipitate which contains calcium sulfate. The phosphoric acid is substantially entirely dissolved in the methanol. Next the methanol containing the dissolved phosphoric acid is separated from the solid precipitate by decantation, filtration or centrifugation. By evaporation of the methanol a phosphoric acid concentrate is obtained, or by the addition of a base to the methanolic acid solution, the corresponding phosphate salts are formed and precipitated in an easily separatable and dryable form.