Obtaining nano calcium fluoride and ammonium sulfate from phosphogypsum

Abstract

This study presents an efficient and sustainable procedure for converting phosphogypsum (PG) waste, along with hydrofluoric acid (HF) and ammonia (NH₃), into valuable materials. The results obtained demonstrate the high efficiency of this proposed procedure, resulting in the synthesis of relatively pure calcium fluoride (CaF₂) nanoparticles and ammonium sulfate ((NH₄)₂SO₄). The latter is recommended for agricultural use as a fertilizer, while the obtained CaF₂ can be utilized in the metallurgical industry. Furthermore, this procedure not only offers a solution for reducing fluorine gas emissions and managing PG waste but also contributes to the conservation of fluorite reserves.