Laboratório de Nanoestruturas Plasmônicas, Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, 36036-900, Juiz de Fora, MG, Brazil.
Laboratório de Nanoestruturas Plasmônicas, Departamento de Química, Instituto de Ciências Exatas, Universidade Federal de Juiz de Fora, 36036-900, Juiz de Fora, MG, Brazil.
Chemosphere. 2023 Oct;338:139490. doi: 10.1016/j.chemosphere.2023.139490. Epub 2023 Jul 12.
Chemical oxidation technologies have been notably used for the mineralization of organic pollutants from aqueous effluents, been especially relevant for the degradation of pesticides. In this context, both tebuconazole (TEB) and 2,4-dichlorophenoxyacetic acid (2,4-D) pesticides were photodegraded by a combined catalyst of TiO and silver nanoparticles irradiated by UV-A light (λ = 368 nm), and the experiments were tracked by surface-enhanced Raman scattering (SERS) spectroscopy. For 2,4-D, the degradation of about 70% was observed after almost 200 min, while for TEB, a decrease of 80% of the initial concentration was observed after approximately 100 min. The SERS monitoring allowed the proposal of some by-products, such as oxidized aliphatic chain and triazole from TEB besides glycolic, glyoxylic and dihydroxyacetic acids from 2,4-D. Their toxicities were predicted through ECOSAR software, verifying that most of them were not harmful to populations of fish, Daphnia and green algae. Thus, the performed oxidative process was efficient in the photodecomposition of TEB and 2,4-D pesticides, inclusive in terms of the decreasing of the toxicity of contaminated effluents.
化学氧化技术已被广泛用于水污染物中有机污染物的矿化，特别是在农药降解方面具有重要意义。在这种情况下，三唑酮（TEB）和 2,4-二氯苯氧乙酸（2,4-D）农药都被 TiO 和银纳米粒子的组合催化剂在 UV-A 光（λ=368nm）下光降解，实验通过表面增强拉曼散射（SERS）光谱进行跟踪。对于 2,4-D，经过近 200 分钟的降解，观察到约 70%的降解，而对于 TEB，初始浓度约 100 分钟后观察到 80%的减少。SERS 监测允许提出一些副产物，如 TEB 的氧化脂肪链和三唑，以及 2,4-D 的乙二醇、乙醛酸和二羟乙酸。它们的毒性通过 ECOSAR 软件进行预测，验证了它们中的大多数对鱼类、水蚤和绿藻的种群没有危害。因此，所进行的氧化过程对 TEB 和 2,4-D 农药的光解非常有效，同时也降低了受污染废水的毒性。
