Preparation of Fe3O4@SiO2@MnO2 microspheres as an adsorbent for Th(IV) removal from aqueous solution

A magnetic nano-composites Fe3O4@SiO2@MnO2 were fabricated for efficient removal of Th(IV) from aqueous solutions, and characterized by SEM, TEM, XRD, FT-IR, BET, VSM, TGA and XPS. And the sorption of Th(IV) on Fe3O4@SiO2@MnO2 were investigated as a function of pH, adsorbent dosage and initial Th(IV) concentration. The results showed that the adsorption maximum was 53.19 mg g(-1) for Th(IV) at pH = 3.5 and T = 298 K. In addition, the adsorption kinetics followed the second-order kinetic model, and the adsorption isotherm could be perfectly depicted by the Langmuir model. Finally, XPS analysis illustrated that the lattice oxygen (M-O) and the surface hydroxyl oxygen (M-OH) participated in adsorption. In brief, the Fe3O4@SiO2@MnO2 material could efficiently eliminate Th(IV) from aqueous solutions, which might become a promising material for adsorbing Th(IV) from environmental wastewater.

Automated summary

A magnetic nano-composites Fe3O4@SiO2@MnO2 was prepared for efficient removal of Th(IV) from aqueous solutions, achieving a maximum adsorption capacity of 53.19 mg g(-1) at pH = 3.5 and T = 298 K. The adsorption kinetics followed the second-order kinetic model, and the adsorption isotherm was well described by the Langmuir model, with lattice oxygen (M-O) and surface hydroxyl oxygen (M-OH) participating in the adsorption process. This material shows promise as a potential material for removing Th(IV) from environmental wastewater.