Min Zhao,Ting Li,Yizhan Zhang,Jiaming Gan,Yiting Zhao,Xin Yu,Lei Wang
Advanced oxidation technology of KrCl excimer lamp activated H 2 O 2 (UV 222 /H 2 O 2 ) have been received widespread attention in the field of water treatment recently, due to the higher radical yield and environmentally friendly nature compared to UV 254 /H 2 O 2 . In this investigation, four representative parahalogenated phenols (HPs) degradation kinetic and mechanisms by UV 222 alone and UV 222 /H 2 O 2 were studied, respectively. The results showed that the photolysis rate constants ( k obs ) under UV 222 followed the order of p -Chlorophenol ( p -CP) > p -Fluorophenol ( p -FP) > p -Bromophenol ( p -BP) > p -Iodophenol ( p -IP), and the degradation rate constants ( k obs ) by UV 222 /H 2 O 2 followed the order of p -FP > p -CP > p -BP > p -IP. The molar absorption coefficient ( ε 2 22nm ) and quantum yield ( Φ 222nm ) of HPs photolysis were measured. Kinetic model simulating results are in fair agreement with the experimental results. Through HPLC-MS analysis and DFT calculation, the impact of halogen ions on the degradation kinetics of HPS by UV 222 and UV 222 /H 2 O 2 was found, the possible reaction pathways and mechanisms were proposed. Compared with UV 254 /H 2 O 2 for removing p -CP, UV 222 /H 2 O 2 was much more energy efficient.
Advanced oxidation processes based on KrCl* excimer lamps (UV 222 -AOPs) have recently received widespread attention in water treatment due to their high radical yields. In this investigation, the degradation of two typical antibiotics, florfenicol (FLO) and ciprofloxacin (CIP), by UV 222 and its combination with hydrogen peroxide (H 2 O 2 ) or persulfate (PDS) were studied, respectively. The dual effects of inorganic anions on the degradation performance of UV 222 /UV 222 -AOPs were determined. It was found that NO 3 – significantly enhanced the photolysis of CIP, and the degradation rate constants increased from 1.03 × 10 -4 mJ −1 cm 2 (without NO 3 – ) to 2.56 × 10 -4 mJ −1 cm 2 (with 1 mM NO 3 – ). However, NO 3 – markedly inhibited the photolysis of FLO, leading to a decrease in the degradation rate constants from 1.18 × 10 -3 mJ −1 cm 2 (without NO 3 – ) to 5.27 × 10 -4 mJ −1 cm 2 (with 1 mM NO 3 – ). HCO 3 – was found to have a certain promoting effect on the photolysis of FLO and CIP, and SO 4 2- has a negligible effect on the photolysis of both antibiotics. The above three inorganic ions decelerated the degradation of CIP and FLO in UV 222 -AOP, where NO 3 – exerted the most inhibition. Through LC-MS analysis and ECOSAR model, the main transformation products were individually determined and evaluated for toxicity. In addition, the performance of UV 222 -AOPs and UV 254 -AOPs in reclaimed wastewater (RWW) treatment were compared, and the steady-state concentration of radicals was measured. This study provided novel insight into the application of UV 222 -AOPs in RWW treatment.
危险品化学品经营许可证（带存储）