Production of Crystalline Urea Phosphate using

Relatively pure and large crystalline urea phosphate of 17-44-0 (N-P2O5-K2O wt%) grade has been obtained from untreated Jordanian wet process phosphoric acid of about 50 % P2O5 content. The modified procedure involves the addition of a certain percentage of mother liquor to the urea and untreated wet process phosphoric acid in the reaction vessel. The preferred reaction temperature was found to be 45oC, and the reaction and nucleation (crystallization) time is 2 to 3 hr. The slurry must be pumped to the cooled crystallizer at 15oC to allow further growth of the urea phosphate crystals and increase product recovery. The urea phosphate crystals produced contain about 80 % of the urea, and phosphoric acid feeds and almost free of the impurities present in the wet process phosphoric acid. This modified procedure has some advantages over the conventional procedure in many aspects such as easy agitation and pumping, less cooling, easy separation of the urea phosphate crystals from the mother liquor, efficient drying, and low energy consumption.