Post electro-catalytically produced H<sub>2</sub>O<sub>2</sub> induced the formation of nano-uranyl peroxide from uranyl(VI)-containing wastewater

<p indent="0mm">Nuclear energy is widely regarded as one of the most clean, low-carbon and highly efficient baseload energies, which can effectively solve for environmental pollution issues from traditional fossil energy sources. However, uranium-containing wastewater associated with the development of nuclear energy, such as mining, refining and spent fuel reprocessing, poses a potential threat to the health of human beings and environmental ecosystems. Hydrogen peroxide (H₂O₂) is an environment-friendly and efficient oxidant with a wide range of applications in many fields. The traditional industrial anthraquinone process for H₂O₂ requires complex infrastructure and is not feasible for small-scale operations. Therefore, developing high-performance catalysts for the small-scale and efficient production of H₂O₂ by photo/electro-catalytic processes can be straightforwardly consumed with hexavalent uranyl ions (U(VI)) for uranium-containing wastewater treatment. In this paper, aiming to the post electro-catalytically produced H₂O₂, we utilized the electrochemical H₂O₂ products to systematically investigate the influences of different environmental media on between the reaction of H₂O₂ and U(VI), including H₂O₂ concentration, initial U(VI) concentration, temperature, pH and interfering ions through the batch experiments. The results show that the removal efficiencies of high U(VI) concentration by <sc>6.72 mM</sc> H₂O₂ were up to 100% at pH = 3.0 and pH = 6.0, and nano-uranyl peroxide were formed in the majority of interfering ions except (Cu²⁺, Fe³⁺, VO₃⁻) ions. This study demonstrates the great potential of electrocatalytic production of H₂O₂ to induce the formation of nano-uranyl peroxide from uranium-containing wastewater.