Highly efficient uranium (VI) remove from aqueous solution using nano-TiO2-anchored polymerized dopamine-wrapped magnetic photocatalyst

Radioactive uranium containing wastewater discharged from uranium mining and associated nonferrous metallurgy posing a serious threat to human health and aquatic ecosystem. In this paper, we attempted to use photocatalytic technology to reduction U(VI) from diluted uranium-containing wastewater and recover dispersed uranium by constructing a highly efficient photocatalyst. A polymerized dopamine (PDA)-wrapped magnetic base was introduced to support spherical anchoring of TiO2 nanoparticles, and the newly designed photocatalyst (TiO2/PDA@Fe3O4) with a particle size of 450∼700 nm had a remarkable multilayer-ball structure and displayed remarkably high recyclability and photocatalytic reduction efficiency for aqueous uranium under UV radiation. Uranyl with an initial concentration of 2.0 mg/L, and solution pH of 6.0 was ∼100% removed within 40 min, and no interference by coexisting anionic and cation ions was not observed. In determination of photocatalytic mechanism, the results showed that nanoscale TiO2 particles on TiO2/PDA@Fe3O4 surface can adsorb U(VI) efficiently and reducing them under UV radiation. Furthermore, TiO2/PDA@Fe3O4 nanocomposites displayed high stability performance, the uranium removal efficiency was greater than 83.5% after six times recycle. The proposed engineered interface fabricate strategy has the potential for use in universal hydro-stable micro/nano-particle production and may contribute to more effective uranium extraction from waste liquids.