在水系统中激进处理酸二烯:一项动力学研究
Stephen P Mezyk1, Maya H Rogalski1, Anh N Dang1
1Department of Chemistry and Biochemistry, California State University at Long Beach, 1250 N. Bellflower Blvd., Long Beach, California 90840, United States.
概括
饮用水中的有毒消毒副产品酸 (HANs) 通过在先进的氧化/减少过程 (AO/RP) 中降解物种有效降解. 这项研究量化了HAN与关键的AO/RP激素的反应性,表明减少途径对水处理最有希望.
科学领域:
- 环境化学环境化学
- 水处理技术水处理技术
- 放射性溶解过程 放射性溶解过程
背景情况:
- 乙二 (HANs) 是饮用水中细胞毒性和基因毒性消毒副产品.
- HAN可以在水中持续存在,因此需要有效的清除策略来直接重新利用水.
- 先进的氧化/还原过程 (AO/RPs) 是去除HANs.的潜在方法.
研究的目的:
- 系统地研究HAN反应的动力学与主要的AO/RP放射解物种.
- 评估不同AO/RP激素 (氧化和还原) 在降解HANs中的有效性.
- 确定使用AO/RPs.去除HAN的最佳条件.
主要方法:
- 电子脉冲放射溶解被用来研究五个HAN与四个关键的AO/RP基的反应.
- 反应是在环境温度和pH值1-7的水溶液中进行的.
- 测量了HAN和水合电子 (eaq-),原子 (H·),基 (·OH) 和硫酸盐基 (SO4-·) 之间的反应速率常数.
主要成果:
- 显著的反应性被观察到减少激素:水合电子 (k = (1-5) × 10 10 M-1 s-1) 和原子 (k = (1-40) × 10 7 M-1 s-1).
- 氧化基的反应性是最小的:基 (k = (0.6-10) × 10 7 M-1 s-1) 和硫酸盐基 (k = (0.2-4) × 10 6 M-1 s-1).
- 这些发现表明,减少途径在HANs被AO/RP降解时占主导地位.
结论:
- 先进的氧化/还原过程有效地从水中去除酸.
- 降低性电子诱导降解是消除HANs在脱气系统中的主要机制.
- 该研究为设计HAN污染水的AO/RP处理策略提供了关键的动力学数据.
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