Hydrothermal Fabrication of Amine-Grafted Magnetic Gelatin Hybrid Composite for Effective Adsorption of Nitrate and Phosphate

Magnetic composites possess benefits like easy separation, high porous structure, chemically modified surface, and good sorption capacity toward toxic ions removal. Herein, amine-grafted magnetic gelatin (AGMGel) composite was prepared and applied for the adsorption of nitrate (NO3 –) and phosphate (PO4 3–) from water. The prepared AGMGel composite minimizes the irrevocable methemoglobinemia (blue baby syndrome) and algae growth (eutrophication) problems, which are often caused by both NO3 – and PO4 3– in water. X-ray diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer, energy dispersive X-ray analysis, Brunauer–Emmett–Teller and scanning electron microscopy were characterized to find the nature of iron oxide (Fe3O4), gelatin (Gel), and amine present in the prepared composite. The contact period, adsorbent dosage, solution pH, initial adsorbate concentration, temperature, and co-anions often affect the adsorption system optimized in batch mode. The removal mechanism of AGMGel composite toward NO3 –/PO4 3– was found to be electrostatic attraction and complexation. The kinetics and isotherms with thermodynamic factors demonstrated the nature and order of the adsorption system. The regeneration and field studies of AGMGel composite were also evaluated.