TiO₂/CPAN-AO heterojunction in-situ grow on carbonized melamine sponge for photocatalytic reduction of uranium (VI)

Extraction of uranium from seawater is of great significance to the development of nuclear energy. Photocatalytic reduction technology offers an innovative solution for the uranium recovery. However, traditional photocatalysts in powder form are limited by recyclable issue. Herein, a constructed novel composite sponge with TiO₂/CPAN-AO binary photocatalyst that improved performance in uranium recovery from seawater on account of its exceptional photocatalytic performance, high selectivity, and recyclability. In addition, a new adsorption system called “Diffusion-Capture-Anchoring” was developed for photocatalytic reduction of uranyl ions. The removal rate of uranium within 105 min was 98%, when the initial uranium concentration was 100 mg/L. The selectivity and specificity of the material for uranium were established by the addition of interfering cations. Antimicrobial experiment proved that a great inhibitory effect on Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Pseudoalteromonas xiamenensis (P. xiamenensis). More importantly, the excellent recycling property of the CS/TiO₂/CPAN-AO was tested via the ten cycles of experiment. As an efficient and recyclable adsorbent, the CS/TiO₂/CPAN-AO composite sponge demonstrates great potential for extracting uranium from the seawater.