Photocatalytic uranium removal from basic effluent by porphyrin-Ni COF as the photocatalyst

• A new green method for uranium removal via photocatalytic produced H 2 O 2 . • Uranium can be recovered without sacrificial agent under air. • Uranium can be removed from basic solution under solar energy. • Removal rate from simulated uranium-containing basic effluent reaches to 95.5%. Photocatalytic uranium removal from radioactive wastewater is considered as a green method to prevent environment contamination. However, almost all photocatalysts are used in anaerobic condition or with extra sacrificial agent. Herein, we report a strategy for non-sacrificial photocatalytic uranium removal from basic solution under air by photocatalyst TT-Por COF-Ni, which was synthesized via Aldamine reaction between 5,10,15,20-(tetra-4-aminophenyl)porphyrin-Ni (TPP-Ni) and thieno[3,2-b]thiophene-2,5-dicarbaldehyde (TT). Hydrogen peroxide (H 2 O 2 ) is generated by photocatalytic reduction of O 2 , and followed by formation of metastudtite via in situ reaction with uranyl. As a result, uranium can be photo-driven removed to 1 ppm residual in basic solution under air atmosphere without adding extra sacrificial agent, and uranium removal reached to 97.1% upon solar illumination. Remarkably, our strategy can recover uranium with 95.5% removal rate from simulated uranium-containing effluent from nuclear fuel cycle in basic condition, which suggests a potential for practical application.