Removal of Cadmium (II) Using CoFe2O4 Powders Synthesized by Solution Combustion Method

Cobalt ferrite (CoFe2O4) powders were successfully prepared by solution combustion synthesis using metal nitrates as oxidant and glycine as fuel at various fuel to oxidant molar ratios (?=0.5, 0.75, 1 and 1.25). The structure, morphology and specific surface area of as-combusted CoFe2O4 powders were characterized by X-ray diffraction, scanning electron microscopy and nitrogen adsorption-desorption techniques. By increasing of fuel content, the specific surface area and pore volume decreased from 285 to 35 m2/g and 1.38 to 0.17 cm3/g, respectively. The as-combusted magnetic CoFe2O4 powders were used as adsorbent for removal of Cd(II). The effect of the contact time showed the kinetics of adsorption process followed the pseudo-second-order model and was controlled by film diffusion process. The adsorption isotherms were also well fitted on the Freundlich model. The as-combusted CoFe2O4 powders at ?=0.75 exhibited excellent adsorption capacity (694 mg g?1) and high adsorption rate.