Abstract
A new CoZn nanoferrite and its moderately calcined counterpart were produced by the polyol method aiming to assess their effectiveness for the removal of Cr(VI) species from aqueous solutions. The produced nanoparticles (NPs) were systematically studied by various techniques. X-ray diffraction revealed the formation of nanosized single-phase cubic spinel-type ferrites, and transmission electron microscopy showed the presence of almost similar to 10 nm sized spherical NPs. Magnetic study showed a superparamagnetic behavior at room temperature and a reasonable Curie temperature for both the as-prepared and calcined NPs. Adsorption study of Cr(VI) onto the moderately calcined NPs was carried out at pH 2.0. The uptake of the Cr(VI) was found to increase rapidly with the increase of the NP dose. Additionally, the adsorption of Cr(VI) onto the nanoferrite was found to follow a pseudo-second-order kinetics in agreement with a chemisorption process. Moreover, the equilibrium data points were found to follow the Langmuir isotherm model with an adsorption capacity of approximate to 16.0 mg g(-1) for an adsorbent concentration of 4.0 mg mL(-1). The nanoadsorbent was also tested in ten adsorption-desorption-regeneration cycles without any significant loss in sorption capacity. All the features demonstrate that the moderately calcined CoZn ferrite is a promising nonmaterial for the treatment of chromium (VI)-bearing wastewaters.