METHOD OF DECOLORIZATION OF PURIFIED PHOSPHORIC ACID

摘要

FIELD: inorganic chemistry, chemical technology. SUBSTANCE: invention relates to method of decolorization of phosphoric acid obtained as result of purification of wet-process phosphoric acid by liquid extraction method using organic solvent and used in production of phosphates of technical and food grading. Method involves treatment of purified phosphoric acid with hydrogen peroxide aqueous solution that is added under layer of acid by discrete 3-5 portions in equal parts as measured for required amount at stirring and process is carried out at temperature of acid feeding for treatment. Treatment of acid with hydrogen peroxide is carried out either before its concentrating or after that and decolorized acid is passed additionally through activated carbon layer. Light transmission coefficient is 92-95%. Method provides to reduce equipment corrosion and enhance effectiveness of hydrogen peroxide consumption. EFFECT: improved method of decolorization. 3 cl, 3 ex