Magnet-Responsive Silica Microrods as Solid Stabilizer and Adsorbent for Simultaneous Removal of Coexisting Contaminants in Water

Because of the differences in physicochemical properties, it is of a great challenge to achieve efficient and simultaneous removal of various pollutants from water only based on one material. In this study, magnetic silica microrods (R-Fe3O4@SiO2) were successfully fabricated and used for the removal of coexisting pollutants (oil, heavy metals, soluble organic dyes) in water. R-Fe3O4@SiO2 could act as an effective solid stabilizer to disperse oil contaminants into droplets, due to its high adsorption energy at the oil water interface. The encapsulated oil by R-Fe3O4@SiO2 could be effectively separated from water by applying a magnetic field. Simultaneously, R-Fe3O4@SiO2 could adsorb soluble cationic dyes and heavy metals through electrostatic interactions. The maximal removal capacity of R-Fe3O4@SiO(2)for various pollutants in water was compared with that of some of the previously reported materials, and they showed a satisfied result. Additionally, the removal capacity of R-Fe3O4@SiO2 particles for multiple coexisting contaminants in water was evaluated. It is worthy to note that R-Fe3O4@SiO2 still showed a great removal capacity for multiple coexisting pollutants even after five runs of a sorption-desorption cycle. These results revealed that this technically simple R-Fe3O4@SiO2 material is a feasible material for the removal of various coexisting pollutants in water, and thus it holds great prospects as a candidate for the one-step water purification in practical applications.