Synthesis of struvite (MgNH4PO4•6H2O) and its use for sorption of nickel ions

The influence of the conditions of the struvite synthesis on its ability to form crystals with developed faces of different forms (hkl) and on the possibility of the subsequent transition to more stable forms was examined. The correlation between the zeta-potential of the struvite particle surface, struvite crystal size, and tendency to form agglomerates was demonstrated. The sorption rate in the system consisting of struvite, nickel ions, ammonium ions, and water can be increased by combining the internal diffusion and recrystallization of the solid interaction products. The possibility of enhancing the sorption performance by properly choosing the anionic composition of solutions of nickel salts for the sorption was revealed. The conditions for preparing struvite for its use as agent for improvement of contaminated soils to immobilize heavy metal ions were substantiated.