Comparative study on early and late-stage crystallization of urea phosphate from untreated Moroccan phosphoric acid

Abstract

Morocco is one of the world’s leading phosphate producers, converting its phosphate reserves into phosphoric acid, which is further used to produce urea phosphate. Urea phosphate is a valuable source of nitrogen and phosphorus for plant growth. However, phosphoric acid purification in Morocco is crucial to ensure high-quality urea phosphate production. In this study, we synthesized urea phosphate via an exothermic reaction of urea and phosphoric acid under optimized conditions for 90 min. Crystals began to form after 60 min, and the final sample was taken after 90 min. Elemental and morphological analyses confirmed the high purity of the synthesized urea phosphate crystals. XRD and FT-IR analyses verified the crystalline phase and elemental composition, focusing on nitrogen (N) and phosphorus (P₂O₅), important nutrients for crops. SEM and microscopy further demonstrated the excellent quality of the final product. Our results suggest that untreated Moroccan phosphoric acid can be effectively used to produce pure urea phosphate crystals, thus providing an effective solution for improving agricultural productivity.