TiO2-Based Sorbent of Lead Ions

The non-magnetic TiO₂ powder and magnetically modified TiO₂ powder were employed for the sorption experiments. FeSO₄.7H₂O was used for synthesis of magnetically responsive TiO₂. The non-magnetic and prepared magnetic materials were characterized by scanning electron microscopy and X-ray diffraction methods. The particle size and specific surface area were determined. A detailed study of the adsorption process performed using batch adsorption experiments was carried out with various concentrations of lead ions and contact time. A flame atomic absorption spectrometer was used for determination of Pb²⁺ ions concentration in solution. Adsorption process has been modeled by the Langmuir and Freundlich isotherms using linear and non-linear regression. The results showed that the adsorption of Pb²⁺ ions on the magnetic and non-magnetic TiO₂ particles occurred in a monolayer. Presence of magnetic iron oxides particles on the surface of sorbents increased the adsorption rate, and increased the maximum amount of adsorbed Pb²⁺ ions per mass in comparison with adsorption on the non-magnetic TiO₂ particles. The magnetically modified TiO₂ particles allow magnetic separation of the sorbents with already adsorbed ions of pollutants.