State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
J Environ Sci (China). 2022 Jul;117:141-150. doi: 10.1016/j.jes.2022.03.046. Epub 2022 Apr 15.
UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5-1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.
UV/过一硫酸盐（UV/PMS）高级氧化工艺因其在水中去除微量污染物的能力而受到广泛关注。然而，在实际的水处理应用中，PMS 处理必须在 UV 处理之前进行，以实现完全接触。在本研究中，磺胺甲恶唑（SMX）被选为目标微量污染物。比较了四种不同的操作方法，包括单独的 UV、单独的 PMS、同时的 UV/PMS 和顺序的 PMS-UV，以比较它们在氯驱动消毒过程中去除 SMX 和消毒副产物（DBP）形成潜力方面的差异。在这四种方法中，UV/PMS 和 PMS-UV 对 SMX 的去除率均超过 90%，没有明显差异。对于原水，PMS-UV 处理后的三氯硝基甲烷（TCNM）形成潜力低于 UV/PMS 处理后的形成潜力。进行 PMS-UV 处理的时间间隔对 SMX 的最终去除效率影响不大。然而，短暂（5 分钟）的预 PMS 处理可显著降低 TCNM 的形成潜力和 DBPs 的遗传毒性。在氯消毒过程中，TCNM 的形成风险随着 PMS 剂量的增加而显著增加，建议在这些实验条件下的适当剂量为 0.5-1.0mmol/L。在碱性条件下，PMS-UV 处理可以增强 SMX 的降解，同时显著降低卤代酮、卤代乙腈和卤代硝基甲烷的形成潜力。本研究表明，适当优化 UV/PMS 工艺可以去除 SMX 并减少其 DBP 的形成。
