Highly efficient sorption of U(VI) from aqueous solution using amino/amine-functionalized magnetic mesoporous silica nanospheres

The amino/amine-functionalized magnetic mesoporous silica nanospheres (MSN-DETA) exhibited relatively high sorption capacity (q_m = 153.68 mg/g) as well as excellent selectivity for U(VI). The U4f_7/2 X-ray photoelectron spectrometry revealed two binding energies at 380.8 ± 0.3 eV (with the proportion of 75.2%) and 382.3 ± 0.3 eV, which indicated the inner-surface complexation mechanism. The sorption isotherms fitted well with the Langmuir model, whereas the sorption kinetics could be fitted by pseudo-second-order model. The U(VI)-loaded MSN-DETA could be efficiently regenerated by acidified EDTA (0.4 M). These findings indicated that MSN-DETA could be used as a potential material for the efficient sorption/separation of U(VI) from wastewater. (author)