College of Architectural and Environmental Engineering, Chengdu Technological University, Chengdu 611730, China.
Center of Big Data for Smart Environmental Protection, Chengdu Technological University, Chengdu 611730, China.
Int J Environ Res Public Health. 2019 May 20;16(10):1781. doi: 10.3390/ijerph16101781.
The degradation effect, degradation mechanism, oxidation kinetics, and degradation products of Atrazine (ATZ) by Ultrasound/Peroxymonosulfate (US/PMS) in phosphate buffer (PB) under different conditions were studied. It turned out that the degradation rate of US/PMS to ATZ was 45.85% when the temperature of the reaction system, concentration of PMS, concentration of ATZ, ultrasonic intensity, and reaction time were 20 °C, 200 μmol/L, 1.25 μmol/L, 0.88 W/mL, and 60 min, respectively. Mechanism analysis showed that PB alone had no degradation effect on ATZ while PMS alone had extremely weak degradation effect on ATZ. HO• and SO• coexist in the US/PMS system, and the degradation of ATZ at pH7 is dominated by free radical degradation. Inorganic anion experiments revealed that Cl, HCO, and NO showed inhibitory effects on the degradation of ATZ by US/PMS, with Cl contributing the strongest inhibitory effect while NO showed the weakest suppression effect. According to the kinetic analysis, the degradation kinetics of ATZ by US/PMS was in line with the quasi-first-order reaction kinetics. ETA with concentration of 1 mmol/L reduced the degradation rate of ATZ by US/PMS to 10.91%. Product analysis indicated that the degradation of ATZ by US/PMS was mainly achieved by dealkylation, dichlorination, and hydroxylation, but the triazine ring was not degraded. A total of 10 kinds of ATZ degradation intermediates were found in this experiment.
研究了超声/过一硫酸盐（US/PMS）在磷酸盐缓冲液（PB）中不同条件下对莠去津（ATZ）的降解效果、降解机制、氧化动力学和降解产物。结果表明，当反应体系温度、过一硫酸盐浓度、莠去津浓度、超声强度和反应时间分别为 20°C、200μmol/L、1.25μmol/L、0.88W/mL 和 60min 时，US/PMS 对 ATZ 的降解速率为 45.85%。机理分析表明，PB 单独对 ATZ 没有降解作用，而过一硫酸盐单独对 ATZ 几乎没有降解作用。US/PMS 体系中同时存在 HO•和 SO•，pH7 下 ATZ 的降解主要由自由基降解主导。无机阴离子实验表明，Cl、HCO 和 NO 对 US/PMS 降解 ATZ 表现出抑制作用，其中 Cl 贡献的抑制作用最强，而 NO 表现出的抑制作用最弱。根据动力学分析，US/PMS 降解 ATZ 的动力学符合准一级反应动力学。浓度为 1mmol/L 的 ETA 将 US/PMS 降解 ATZ 的速率降低至 10.91%。产物分析表明，US/PMS 降解 ATZ 主要通过脱烷基化、二氯化和羟基化实现，但三嗪环未被降解。本实验共发现 10 种 ATZ 降解中间产物。
