检测低度的自由可用的是一种方便的减少方法 - - 使用硫酸作为灭剂
Meiyao Han1, Shiyue Huang1, Xiaoxiao Zhang2
1College of Civil Engineering, Sichuan Agricultural University, Dujiangyan, 611830, China.
Chemosphere
|October 26, 2024
概括
一种新方法通过将其减少为离子来准确测量可自由利用的 (FAC). 与传统方法相比,这种技术提供了较低的检测极限和更好的抗干扰的消毒副产品 (DBPs).
科学领域:
- 环境化学环境化学
- 分析化学 分析化学
- 水处理 处理水的方法
背景情况:
- 消毒是必不可少的,但通过与溶解有机物 (DOM) 反应,形成有害的消毒副产品 (DBPs).
- 精确测量自由可用的 (FAC) 对于有效的消毒和最大限度地减少有毒DBP形成至关重要.
研究的目的:
- 开发一种方便可靠的方法来量化自由可用的 (FAC) 度.
- 评估常见的水矩阵和消毒副产品 (DBPs) 对拟议的FAC检测方法的干扰.
主要方法:
- 使用硫酸 (Na2SO3) 的新型还原方法,将FAC中的氧化转化为离子 (Cl-).
- 使用离子色谱测量化物离子 (Cl-) 的量化,以确定FAC度.
- 将新方法与DPD色度测量,度测量和UV方法进行比较,包括使用DOM,离子和各种DBP进行干扰研究.
主要成果:
- 与传统的FAC检测技术相比,硫酸减少方法显示了较低的检测极限和更高的抗干扰性.
- 像DOM和离子这样的常见水成分对该方法的准确性产生了最小的影响 (<3.6%).
- 碳化DBPs (C-DBPs) 没有干扰,而化DBPs (N-DBPs) 的干扰是可以忽略不计的,这使得该方法适用于C-DBP主导的样本.
结论:
- 拟议的减少方法提供了FAC的精确确定,这对于评估消毒水中的残留有价值.
- 这种技术非常适合用于碳化DBP占主导地位的化工艺.
- 该方法为实验室和现实世界水处理应用中的FAC监测提供了强大的替代方案.
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