Removal of thorium and uranium from aqueous solution by adsorption on hydrated manganese dioxide

The hydrated manganese dioxide (HMO) was synthesized by hydrothermal process using MnSO4 and KMnO4. The adsorption of HMO for Th(IV) and U(VI) were investigated by batch static adsorption experiments. The HMO and MnO2 were characterized by FT-IR, XRD and SEM. At the same time, the adsorption mechanism is discussed. The adsorption process was in line with the pseudo-second-order kinetic model and Langmuir isothermal model. The maximum adsorption capacities were Th (T=308K, C-0=200mgL(-1), q(max)=218.34mgg(-1)) and U (T=308K, C-0=200mgL(-1), q(max)=55.19mgg(-1)).