Yajie Qian, Xiang Liu, Ke Li
Mar 15, 2020
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Influential Citations
32
Citations
Journal
Chemical Engineering Journal
Abstract
Abstract The extensive use of cephalosporin antibiotics (CEFs) leads to the frequent detection of CEFs in different aquatic matrices. Sulfate radical based advanced oxidation processes are efficient in eliminating CEFs. However, the efficiency of CEFs degradation in elevated salt concentration and the transformation products, as well as the corresponding toxicity are still unknown. In this study, CEFs degradation by thermally activated persulfate (PS) in various matrix components were investigated systematically. CEFs degradation could be promoted in Cl− and HCO3− containing matrices, while the mixed matrices of NOM with salt could have an inhibitory effect on CEFs degradation. SO4 −, OH and chlorine radicals were identified to contribute to CEFs transformation in the presence of Cl−. Based on the pseudo-steady kinetic modeling, the contribution of chlorine radicals was estimated to be >90% as Cl− concentration increased to 50 mM. CO3 − was the predominant radical for CEFs degradation in the HCO3− containing matrix. However, the contribution of CO3 − was much less than chlorine radicals, and 70–80% of CEFs degradation was ascribed to CO3 − at HCO3− concentration of 500 mM. The same major products were identified in non-matrix and matrix containing systems, but the products concentration and the evolution rate were enhanced in matrix containing systems. The acute toxicity assay demonstrated that the toxicity of CEFs solution was reduced by thermally activated PS in both non-matrix and matrix containing systems. Compared with surface water and wastewater, CEFs degradation was promoted in high salt containing hospital wastewater, suggesting that thermally activated PS is a promising approach to treat antibiotics in high salinity wastewater.