Preparation and Characterization of Nano-Sized Iron-Titanium Mixed Oxide for Removal of Some Lanthanides from Aqueous Solution

Nano-structured iron(III)-titanium(IV) mixed oxide, Fe-O-Ti, was prepared by co-precipitation technique and characterized using Transmission Electron Microscopy, Fourier Transform Infra Red, Energy Dispersive X-ray spectroscopy, and Thermal Analysis. The particle size of the prepared material was found to be 10-15 nm. The sorptive potential of nano-composite, Fe-O-Ti, for the removal of some lanthanide elements (including, Ce, Nd, and Gd) was assessed in this work. The percent uptake was found to be 95.6%, 89.5, and 81.9 for Ce3+, Nd3+, and Gd3+ ions, respectively. Three kinetic models, pseudo-first-order, pseudo-second-order, and intra particle diffusion models, were tested. The results indicated that the pseudo-second-order model is more applicable for the sorption process. The experimental equilibrium data were tested for the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models; it was well predicted by the Freundlich model. The thermodynamic parameters were calculated. The results indicated that the nano-sized iron-titanium mixed oxide can be considered as a promising material for the removal of some lanthanides from aqueous solution.