Activation ability of Yellow River (Huanghe) suspended sediment to degrade carbamazepine pollutants in water environment using peroxymonosulfate: Performance, mechanism, and potential toxicity evaluation

By constructing a novel heterogeneous persulfate activation system, the ability of Yellow River's suspended sediment (SS) to promote in-situ oxidative degradation of carbamazepine (CBZ) by peroxymonosulfate (PMS) in water environment was investigated. Our results have shown that the SS could efficiently activate PMS to remove carbamazepine pollutants from water environment. In the SS/PMS system (without any other catalysts), at the SS dosage and PMS concentration of 4 g/L and 6 mM, respectively, the CBZ degradation efficiency could reach 81.7 % within 6 h at natural pH, compared with 15.6 % in PMS alone system. During the CBZ degradation process, the SO4 center dot- and (OH)-O-center dot were the dominant radicals in SS/PMS system. The Fe-O complexation and pi-pi* stack-up on the surface of SS were the main active sites to activate the PMS. The degradation intermediates and potential pathways in the reaction process were analyzed by density functional theory (DFT) calculation and liquid chromatography mass spectrometry (LC-MS). Further, the ECOSAR results confirmed the decreased biological toxicity of CBZ after degradation in SS/PMS system. These findings demonstrated the efficient application of Yellow River's suspended sediment for in-situ remediation of antibiotics contaminated water, with more availability and economic feasibility, especially suitable for treating wastewater from antibiotic manufacturing companies.