Advanced Treatment of the Antibiotic Production Wastewater by Ozone/Zero-Valent Iron Process

In this study, ozone/zero-valent iron (ZVI) process is investigated to treat the refractory noxious antibiotic production wastewater. Effects of reaction conditions such as initial pH (2.5-8), ozone flow rate (0-0.5 L min(-1)), Fe-0 dosage (0-7 g L-1), stirring speed (0-400 rpm), temperature (8-80 degrees C), and reaction time (0-60 min) on biochemical oxygen demand after five days (BOD5), chemical oxygen demand (COD) removal are studied, respectively. The results showed that high COD removal (79.9%) and BOD5/COD ratio (0.36) are obtained under the optimal conditions (initial pH 2.5, Fe-0 dosage = 60 g L-1, ozone flow rate = 0.25 L min(-1), reaction temperature = 30 degrees C, stirring speed = 300 rpm, reaction time = 60 min). The results indicate that refractory noxious compositions can be transferred and decomposed by the ozone/ZVI process dramatically. In addition, three control experiments (i.e., air/ZVI process, ZVI process, and ozone process) are performed to confirm the superiority of the ozone/ZVI process. Moreover, the degradation process is analyzed by UV-vis, Fourier-transform infrared (FTIR), and excitation-emission matrix (EEM) fluorescence spectroscopies. Therefore, the ozone/ZVI process is a potential and effective method for the advanced treatment of antibiotic production wastewater.