School of Environment, Tsinghua University, Beijing 100084, China; School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China.
School of Environment, Tsinghua University, Beijing 100084, China; School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100084, China.
Sci Total Environ. 2022 Feb 1;806(Pt 4):151372. doi: 10.1016/j.scitotenv.2021.151372. Epub 2021 Oct 30.
Monochloramine (NHCl) oxidant combined with a Ultraviolet (UV)-Light-emitting-diode (LED) light source forms a new advanced oxidation process (AOP), which can achieve high-efficiency degradation of carbamazepine (CBZ). The degradation of CBZ displayed pseudo-first-order reaction kinetics (R > 0.98, k = 0.0043 cm mJ at pH 7). The degradation of CBZ was dependent on UV-LED wavelength, with maximum degradation efficiency observed at 265 nm since it was the lowest wavelength studied among UV-LEDs. Variation in pH across the range, which might be expected under normal environmental conditions (pH 6-8), and the presence of Cl had no significant effect on the degradation efficiency of CBZ, while the presence of HCO and natural organic matter (NOM) inhibited degradation. Electron paramagnetic resonance (EPR) experiments detected OH in the system. Probe compounds were used to distinguish the contribution of reactive chlorine species (RCS). It was proved that OH and Cl played major roles and OH was responsible for around 50% of the observed degradation of CBZ. Eight transformative products (TPs) in the degradation process of CBZ were identified, with a generally decreasing toxicity. The concentration of disinfection by-products (DBPs) formed during CBZ degradation was all within limits of WHO and China standard for drinking water. Although the concentration of nitrogen-containing DBPs (N-DBPs) was the lowest, N-DBPs were the main contributors to toxicity, and these would require more attention in practical applications. UV-LED/NHCl AOP was identified as an effective way to degrade pharmaceutically active compounds.
一氯胺 (NHCl) 氧化剂与紫外线 (UV)-发光二极管 (LED) 光源结合形成一种新的高级氧化工艺 (AOP)，可实现高效降解卡马西平 (CBZ)。CBZ 的降解符合假一级动力学反应 (R>0.98，k=0.0043 cm mJ，pH 为 7)。CBZ 的降解取决于 UV-LED 波长，在 265nm 时降解效率最高，因为它是研究的 UV-LED 中最低的波长。在正常环境条件下 (pH 为 6-8)，预计会发生 pH 变化，而 Cl 的存在对 CBZ 的降解效率没有显著影响，而 HCO 和天然有机物 (NOM) 的存在则抑制了降解。电子顺磁共振 (EPR) 实验检测到系统中存在 OH。探针化合物用于区分活性氯物种 (RCS) 的贡献。结果证明，OH 和 Cl 起主要作用，OH 负责观察到的 CBZ 降解的约 50%。在 CBZ 降解过程中鉴定出 8 种转化产物 (TP)，其毒性普遍降低。在 CBZ 降解过程中形成的消毒副产物 (DBP) 的浓度均在世界卫生组织和中国饮用水标准的限制范围内。尽管含氮 DBP (N-DBP) 的浓度最低，但 N-DBP 是毒性的主要贡献者，在实际应用中需要更多关注。UV-LED/NHCl AOP 被确定为一种有效降解药物活性化合物的方法。
