Process for the preparation of diammonium phosphate and potassium nitrate from potassium phosphate and ammonium nitrate

摘要

Diammonium orthophosphate is prepared by reacting at a constant elevated temperature ammonium nitrate and dipotassium orthophosphate in an aqueous phase and in relative proportions to yield a solid phase consisting of substantially pure diammonium orthophosphate which is separated from the aqueous solution consisting essentially of water, diammonium orthophosphate and potassium nitrate. The aqueous phase of ammonium nitrate and dipotassium orthophosphate is obtained by reacting ammonia with a mixture of solid and aqueous phases containing NH4+, K+, NO3-an PO43- ions, for example ammonium nitrate and monopotassium orthophosphate. The reaction temperature is in the range 80 DEG C. to 100 DEG C. On cooling the product aqueous solution phase to between 30 DEG C. to 40 DEG C. solid potassium nitrate separates out and can be recovered.