A study on the preparation and application of a core–shell surface imprinted uranyl magnetic chelating adsorbent

A core–shell surface imprinted uranyl magnetic chelating adsorbent (UMCA) was synthesized by combining the sol–gel process with the surface molecular imprinting technique (SMIT). A specific salophen and uranyl–salophen were designed and synthesized. Then, the synthesized uranyl–salophen complex was used as a template (in which uranyl is the target analyte), 3-aminopropyltriethoxysilane as a functional monomer and tetraethylorthosilicate as a cross-linker. The obtained UMCA was characterized by a variety of modern analytical and detection techniques. The adsorbent can be used for the solid-phase extraction of uranyl with good selectivity, high adsorption capacity, magnetic separation characteristics and good reusability. The chelating sorbent was successfully applied for the separation of uranyl, followed by multiphase photocatalytic resonance fluorescence method determination in several environmental water samples with a relative standard deviation of <5.48% and spiked recoveries of 92.5% to 103.0%. The adsorption mechanism was preliminarily discussed.