Adsorption of selenium (Se4+) ions pollution by pure rutile titanium dioxide nanosheets electrochemically synthesized
Ahmed Mahdi Rheima, Mahdi A. Mohammed, Shaimaa Hamed Jaber, Shahad Abbas Hameed
Abstract
ABSTRACT In this work, pure rutile titanium dioxide (TiO 2 ) nanosheets are synthesized by the electrochemical deposition method using a rectangular titanium plate (4 cm × 2 cm × 0.1 cm) as both cathode and anode with a current density of 9.2 × 10 –3 mA/cm 2 for 3 h. The rutile TiO 2 nanosheets are investigated by both scanning electron microscopy and transmission electron microscopy measurements, and their crystal structure is obtained using the X-ray diffraction technique. The Brunauer–Emmett– Teller analysis was shown the surface area of the rutile phase was 52 m 2 /g. The electrochemical synthesized rutile TiO 2 nanosheets behave as an attractive adsorbent for Se 4+ ions from their aqueous solutions. We examined the impact of contact time, pH, adsorbent mass, temperature and initial concentration of Se 4+ ions. The Se 4+ ions isotherm adsorption showed a good fit with Freundlich isotherm and Langmuir models. The thermodynamic study was done to calculate the ΔS, ΔH and ΔG parameters, which obtained 7.39 kJ/mol, 39.32 J/mol K, and –4.32 kJ/mol, respectively. Moreover, the kinetic study showed the adsorption behaved as pseudo-second-order.