Facile synthesis, characterisation and application of zinc ferrite in removal of uranium from water by adsorption.

The present study features about the adsorption efficacy of Zinc ferrite (ZnFe₂O₄) in removing uranium from both synthetic and real groundwater samples. ZnFe₂O₄ was synthesized via the Solution Combustion Method and subsequently characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and spectroscopic techniques, including Fourier transform Infrared (FTIR) spectroscopy and Raman spectroscopy, to assess its structural properties. The textural characteristics of the synthesized material were examined through N₂ adsorption-desorption isotherm analysis. Furthermore, X-ray photoelectron spectroscopy (XPS) and Electron spin resonance (ESR) spectroscopy were used to check and investigate the electronic states and magnetic properties of ZnFe₂O₄, respectively. Parametric batch adsorption experiments were conducted at ambient conditions by varying the uranyl (U(VI)) concentration (10-50 ppm), contact time (0-90 min), adsorbent dosage (0.1-1 g), and solution pH (3-10). The ZnFe₂O₄ nanoparticles exhibited >90 % of U (VI) adsorption at a contact time of 60 min, at pH 6, and an adsorbent dosage of 0.3 g for a 10-ppm U(VI) solution. The adsorption process was best described by the Langmuir model, with a maximum adsorption capacity of 5 mgg-1. Additionally, kinetic studies revealed a pseudo-second-order kinetic model with an equilibrium adsorption capacity of 28.68 mgg-1. The application of 0.3 g of ZnFe₂O₄ was also found to facilitate approximately 90 % U(VI) removal from groundwater samples. The ZnFe₂O₄ nanoparticles demonstrated notable adsorption efficiency and regeneration capability, sustaining performance over five consecutive adsorption-desorption cycles. These findings suggest that ZnFe₂O₄ has potential for remediation of U(VI)-contaminated water under ambient conditions.