Nano-TiO2 Imparts Amidoximated Wool Fibers with Good Antibacterial Activity and Adsorption Capacity for Uranium(VI) Recovery

Marine bacteria play a key role in marine ecosystems and are one of the main causes of biofouling. Biofouling of adsorbents that are used for uranium recovery usually results in a decrease in uranium recovery. A novel adsorbent with antibacterial activity for uranium recovery in bacterial environments was prepared in our study to address this concern. Amidoxime-functionalized wool fibers with nano-TiO2 particles (Wool-AO@TiO2) was synthesized by radiation-induced graft polymerization combined with in situ coprecipitation of nano-TiO2 particles onto the wool fibers. The presence of nano-TiO2 on the adsorbent was verified by scanning electron microscopy with energy-dispersive X-ray spectroscopy. The maximum uranium adsorption capacity of Wool-AO@TiO2, acquired from the Langmuir isotherm, was 113.12 mg/g. The introduced nano-TiO2 imparted excellent antibacterial activity to Wool-AO@TiO2. The inhibition of Staphylococcus aureus and Escherichia coli by Wool-AO@TiO2 was 95.2% and 90%, respectively. The adsorption capacity was mostly unaffected in bacterial environments, even after four cycles of culturing with bacteria. These results suggest that the prepared Wool-AO@TiO2 adsorbent may promote the development of novel antifouling adsorbents for uranium recovery from seawater.