CIEPQPF - Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Pólo II, Rua Sílvio Lima, 3030-790 Coimbra, Portugal.
CIEPQPF - Department of Chemical Engineering, Faculty of Sciences and Technology, University of Coimbra, Pólo II, Rua Sílvio Lima, 3030-790 Coimbra, Portugal.
Sci Total Environ. 2020 May 20;718:137321. doi: 10.1016/j.scitotenv.2020.137321. Epub 2020 Feb 14.
Nitrogen-doped TiO was applied in photocatalytic ozonation reactions for the degradation of a mixture of five parabens under UVA radiation, being evaluated the influence of the reaction medium. The initial mixture parabens concentration considered in these experiments was 50 mg L. The parabens degradation rate was considerably enhanced under neutral pH, specially using a buffered solution, leading to a complete removal under 60 min and with transferred ozone dose (TOD) 36% lower compared to reaction under natural conditions. Isopropanol, known radical scavenger, impeded the complete contaminants removal, affecting the reaction route and by-products formation, but when KI was jointly added, total removal was achieved under 30 min and with a TOD of 25.9 mg L. Parabens depletion was also improved in the presence of Cl, SO and HCO, commonly present in wastewaters. The use of river water (RW) and a secondary wastewater (SWW) as water matrices maintained the process efficiency with lower TOD required, and treated solutions presented lower phytotoxicity towards Lepidium sativum.
氮掺杂 TiO 用于光催化臭氧化反应，在 UVA 辐射下降解五种对羟基苯甲酸酯的混合物，评估了反应介质的影响。这些实验中考虑的初始对羟基苯甲酸酯混合物浓度为 50mg/L。在中性 pH 下，特别是使用缓冲溶液，对羟基苯甲酸酯的降解速率大大提高，在 60 分钟内完全去除，与在自然条件下相比，转移臭氧剂量（TOD）降低了 36%。异丙醇是一种已知的自由基清除剂，它阻碍了污染物的完全去除，影响了反应途径和副产物的形成，但当联合添加 KI 时，在 30 分钟内实现了完全去除，TOD 为 25.9mg/L。在废水中常见的 Cl、SO 和 HCO 存在下，对羟基苯甲酸酯的消耗也得到了改善。使用河水（RW）和二级废水（SWW）作为水基质，保持了较低 TOD 要求的处理效率，处理后的溶液对蕹菜的植物毒性较低。
