Biochar Loaded with CuFeO2 Activated Persulfate to Degrade Antibiotics of the Soil
CuFeO2 nanoparticles were decorated on biochar by one-step hydrothermal method to form the CuFeO2/BC catalyst for persulfate(PS)activation and application of CuFeO2/BC in sulfadiazine(SDZ)contaminated soil was explored in this study.The influence of some key factors such as catalyst doses,PS concentration,initial pH and different soil types on degradation of SDZ were investigated.The results showed that CuFeO2/BC system has better catalytic performance and PS utilization efficiency compared with the pure CuFeO2.Under the condition of CuFeO2/BC dosage of 8 g/kg and PS addition of 3 g/kg,91.72％SDZ(initial concentration of 20 mg/kg)could be removed from the soil within 120 minutes.Furthermore,the mechanism of the CuFeO2/BC/PS system was revealed by quenching experiments and electron paramagnetic resonance(EPR)tests.It demonstrated that active species(SO4·-,HO·,O2·-)were involved in SDZ degradation,the weak EPR signal confirmed the existence of 1O2 but not participated in the degradation of SDZ.The steady-state concentrations of HO·and SO4·-were calculated by using free radical probes.Afterwards,the contribution rates of SO4·-,HO·,O2·-to the degradation of SDZ were obtained to be 43.89％,32.87％,and 23.24％,respectively.Combined X-ray photoelectron spectroscopy revealed that the high catalytic efficiency was attributed to the synergistic effect of Cu+/Cu2+and Fe2+/Fe3+redox cycles.These findings help to achieve more comprehensive understanding of the heterogeneous activation process of PS by CuFeO2/BC to degrade SDZ in actual contaminated sites.
万方数据
