-化物复合物的形成损害了基凝固的脱效率
Ziniu Deng1, An Xu1, Xin Wei1
1State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
Environmental science & technology
|August 6, 2024
概括
基于的凝结剂对除化作用的效果不如人们所认为,形成不可替换的化物种. 这些物种可以在环境中重新转化为自由化物,超过排放限制.
科学领域:
- 环境化学环境化学
- 水处理技术水处理技术
- 材料科学 材料科学 材料科学
背景情况:
- 基于的凝固是一种常见的方法,用于从工业废水中去除化物.
- 现有的方法可能低估了化物总含量,可能导致不遵守排放法规.
研究的目的:
- 制定一项协议,用于区分处理废水中的不同类型的化物.
- 研究化物与凝固剂结合的机制.
- 评估基于的脱化对环境的长期影响.
主要方法:
- 开发了一种区分自由化物 (F-),可交换化物 (EF) 和不可交换化物 (NEF) 的协议.
- 利用19F/23Al NMR和ESI-MS分析化物种及其与的相互作用.
- 对光伏和电废水进行了实验,使用不同剂量的凝剂.
主要成果:
- EF与AlO6形成表面复合体,而NEF则被纳入聚的AlO4核心.
- 由于NEF受到固体阻碍,因此不能与CDTA进行交换.
- 虽然自由F-水平下降了,但总化物 (包括EF和NEF) 超过了排放限制.
结论:
- 基于的凝固产生了大量的EF和NEF,限制了其脱效率.
- 在自然水中,EF和NEF可以转化为自由化物,构成环境风险.
- 目前的基于的脱化实践可能不符合严格的环境标准,原因是形成了持久的化物种.
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