Rapid Degradation of Chlortetracycline Using Hydrodynamic Cavitation with Hydrogen Peroxide
Meng Chen, Min Meng, Xun Sun, Congcong Gu, Huiyun Zou, Xuewen Li
Abstract
Chlortetracycline (CTC), which has been frequently detected in surface water, is generated primarily by the discharge of high-concentration CTC wastewater from pharmaceutical and livestock plants. The development of effective CTC degradation technology is critical. In this study, the extent of CTC degradation at 80 mg/L was investigated by combining hydrodynamic cavitation (HC) and hydrogen peroxide (H2O2). The results indicate degradation ratios of 88.7% and 93.8% at 5 and 30 min, respectively. Furthermore, the possible mechanisms of CTC degradation were determined via HPLC-MS. The CTC degradation pathways include ring openings, C–N bond cleavage, demethylation, dehydroxylation, and desaturation in the sole system of HC, and a series of additional reactions, such as glycine conjugation and the cleavage of C–C double bonds, occurs in the binary system of HC + H2O2. Nevertheless, the treated water poses ecological risks and cannot be directly discharged into the environment. Therefore, HC + H2O2 treatment may be a rapid and effective primary method for the degradation of high-concentration CTC in pharmaceutical factories.