Eco-friendly and low-cost amidoxime-functionalized microcrystalline cellulose/mesoporous silica composite for the selective adsorption of U(VI) from aqueous solution

Eco-friendly and low-cost composite, amidoxime-functionalized microcrystalline cellulose/mesoporous silica (MCC/MS-AO), were synthesized by co-condensation method. The obtained materials were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and N 2 adsorption–desorption analysis. Batch experiments were carried out to study the adsorption capacity of U(VI) on MCC/MS-AO. The results show that the material has good adsorption capabilities for U(VI) including high capacity, good selectivity, and reusability. The adsorption process conforms to pseudo-second-order kinetic model and Langmuir model, and it is spontaneous and endothermic. Finally, the possible adsorption mechanism was further studied by X-ray photoelectron spectroscopy (XPS) techniques. Graphical abstract