Abstract
Adsorption of thorium onto nitric acid modified multi-walled carbon nanotubes was investigated by central composite design as a function of contact time, pH, initial thorium concentration and temperature. The results showed that optimum uptake capacity was 65.75±2.23 mg·g−1 with respect to pH=4, initial thorium concentration of 100 mg·L−1, 25 °C and 15 min contact time. Thermodynamic parameters [standard enthalpy (ΔH0), entropy (ΔS0), and free energy (ΔG0)] were calculated, and the results indicated that adsorption was endothermic. Langmuir, Freundlich and Dubinin-Radushkevich isotherms have been investigated in order to characterize the adsorption process in the range of 25–100 mg·L−1 initial thorium concentration. The Freundlich isotherm is the best suited as a model because it has the highest correlation coefficient (R2=0.9485). The pseudo-second order kinetics well defined the adsorption process.
Dye degradation performance, bactericidal behavior and molecular docking analysis of Cu-doped TiO2 nanoparticles
