聚胺膜模型单体与二氧化的反应:动力学,途径和影响
Ao Wang1, Shouliang Huo2, Jean-Philippe Croué3
1Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Water research
|June 8, 2023
概括
二氧化 (ClO2) 为控制反透 (RO) 系统中的生物污染提供了一个有希望的替代. 研究表明,ClO2 降解芳香聚胺模型单体的速度比慢,这表明在海水淡化处理中改善了膜寿命.
科学领域:
- 水处理技术水处理技术.
- 膜科学是一种科学.
- 氧化化学 氧化化学 氧化化学
背景情况:
- 芳香聚胺 (PA) 膜对于反透 (RO) 至关重要,但易受用于生物污染控制的自由的降解.
- 二氧化 (ClO2) 作为一种替代消毒剂,以减轻PA膜损伤,正在被探索.
研究的目的:
- 研究PA膜模型单体 (甲和甲) 与二氧化 (ClO2) 之间的反应动力学和反应机制.
- 评估ClO2作为RO系统预处理的潜力,以控制生物污染,同时最大限度地减少膜降解.
主要方法:
- 进行了动力学研究,以确定在不同pH值和温度下与ClO2发生的二 (BA) 和二 (AC) 反应的速率常数和激活能.
- 分析了降解途径和副产品的形成.
- 开发了一种运动模型,并根据实验数据进行验证.
主要成果:
- 用BA和AC进行ClO2反应的速率常数在pH8.3和21°C下确定.
- 反应显示了强大的基辅和显著的温度依赖.
- 二氧化的降解通过两种途径发生:对二氧化部分的攻击 (主要) 和氧化解 (小).
- 用ClO2处理的BA的半衰期比在典型的海水条件下用处理的BA要长得多.
结论:
- 与相比,二氧化与PA模型单体具有较慢的降解动力学.
- 这些发现支持ClO2在海水淡化过程中RO处理之前用于生物污染控制的潜在应用.
- 在RO应用中,ClO2为提高PA膜的耐用性提供了一个可行的选择.
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