Synthesis and Characterization of Nano-CoFe2O4 Ferrite: Application to the Adsorption of AG25 Dye in Aqueous Solution.

Nano spinel of cobalt ferrite CoFe₂O₄ (NCF) has been synthesized by Sol–gel auto-combustion method and used as an adsorbent to remove Acid Green AG25 dye from aqueous solution. The NCF was investigated by XRD, Rietveld refinement, SEM coupled with EDX, VSM, FTIR and pH of the zero-point charge pH_zpc. The efficiency of the treatment was evaluated according to the characteristic parameters influencing the adsorption process: adsorbent dose, contact time, initial dye concentration, initial solution pH and temperature. The adsorption of AG25 followed pseudo-second order kinetic model. The equilibrium adsorption data fit to the Langmuir isotherm with a maximum capacity of 8.71 mg g⁻¹. Thermodynamic data revealed that the process was exothermic, spontaneous and a physisorption nature. Through the established adsorption process and magnetization measurements, a mechanism was proposed to highlight the idea that the nano spinel of cobalt ferrite material has both magnetic and electronic characteristics. NCF is an efficient adsorbent, low cost, easily synthesized and environmental friendly for removal AG25 from aqueous solution.Highlights: Adsorption of AG25 dye by nanoferrite CoFe₂O₄ Synthèse by sol–gel auto-combustion mechanism study Combination between results of adsorption process and the proved magnetic properties CoFe₂O₄ material has both magnetic and electronic characteristics which can be beneficial for water pollution control [ABSTRACT FROM AUTHOR]