Surface modified magnetic Fe3O4 nanoparticles as a selective sorbent for solid phase extraction of uranyl ions from water samples

► A new sorbent based on functionalized magnetite nanoparticles with quercetin is reported. ► The quercetin based magnetic nanoparticles could be used as a sorbent to remove toxic uranyl ions from water samples. ► The sorbent provides a rapidly and easy separation of uranyl ions only by using a permanent magnet. ► This technique is considered more efficient separation compared to conventional filtering or centrifuging methods for the removing of the sorbent. In this study, silica-coated magnetic nanoparticles modified with quercetin were synthesized by a sol–gel method. These magnetic nanoparticles were assessed as a new solid phase sorbent for extraction of uranyl ions from aqueous solutions. The crystal and chemical structures and magnetic property of the new sorbent were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectrophotometer (FT-IR), and vibration sample magnetometer (VSM). The experimental parameters affecting the extraction efficiency of uranyl ions from aqueous solutions using the synthesized sorbent were optimized by means of the response surface methodology. The adsorption equilibrium of uranyl ions onto the sorbent was explained by Langmuir isotherm and maximum monolayer adsorption capacity was found 12.33mg/g. The synthesized sorbent was applied to extraction of uranyl ions from different water samples.