Degradation of Diclofenac Sodium by Pre-magnetization Fe /Persulfate System: Efficiency and Degradation Pathway Study

摘要

The degradation of diclofenac sodium (DCF) in pre-magnetization Fe-0/persulfate (Pre-Fe-0/PS) and Fe-0/PS systems were studied in detail in this study. The influencing operational conditions (initial PS dosage, Fe(0)dosage, and pH) were studied for their effects on the DCF degradation. The removal rate constant for DCF by the Pre-Fe-0/PS system was 2.1-6.2 times higher than that of the Fe-0/PS system. A higher TOC removal efficiency (81.5%) was observed during the mineralization of DCF in the Pre-Fe-0/PS process than that of the Fe-0/PS process (70%). The results of electron paramagnetic resonance (EPR) confirmed that the Pre-Fe-0/PS system could produce much more(center dot)OH and SO(4)(-center dot)at a faster rate than the Fe-0/PS system. Moreover, the degradation mechanism of DCF by the Pre-Fe-0/PS process was elucidated. This work would provide a perspective on the Pre-Fe-0/PS process for efficient degradation of DCF, exhibiting advantages to removing DCF, such as broaden the range of working pH and reduce the amount of chemicals. So, it is an efficient and potential method to remove DCF from wastewater by the Pre-Fe-0/PS process.