Potential of cobalt ferrite nanoparticles (CoFe₂O₄) for remediation of hexavalent chromium from synthetic and printing press wastewater

Cobalt ferrite (CoFe₂O₄) nanoparticles were successfully synthesized, characterized and utilized for the treatment of chromium containing synthetic wastewater and printing press wastewater. Characterization of CoFe₂O₄ nanoparticles was carried out by XRD, TEM, SEM, AFM, VSM and BET surface area analysis. TEM analysis confirmed the formation of nanoparticles in the range of approximate 12-21 nm having the surface area of 41.31 m² g^-1. The saturation magnetization of nanoparticles was determined to be 50.8 Am² kg^-1. Langmuir adsorption capacity of CoFe₂O₄ nanoparticles was calculated to be 16.73 mg g^-1. Kinetic study revealed that the Cr(VI) removal on CoFe₂O₄ nanoparticles followed the pseudo-second-order kinetic model. Further, the temperature study revealed the endothermic nature of Cr(VI) adsorption. Thermodynamic study revealed the feasibility of Cr(VI) adsorption on CoFe₂O₄ nanoparticles. Desorption study suggested that nanoparticles could be efficiently reused up to three cycles. The present study demonstrated that synthesized nanoparticles were quite efficient for the treatment of chromium ions and other metallic ions from printing press wastewater which further suggested that CoFe₂O₄ nanoparticles could be successfully used for the treatment of metal- rich industrial effluents.