在中性条件下由CoO快速激活甲酸:多种反应性物种的贡献
Zizheng Liu1, Jinlan Tang1, Lu Liu1
1School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
Environmental research
|September 26, 2024
概括
一种新的一氧化物 (CoO) 激活酸 (PAA) 工艺有效地去除水中的新出现的微污染物. 这种先进的氧化过程利用了活性氧物种,并且可以在可持续的水处理中高度重复使用.
科学领域:
- 环境化学环境化学
- 催化剂是一种催化剂.
- 水处理 处理水的方法
背景情况:
- 新出现的微污染物对水生生态系统和人类健康构成风险.
- 传统的水处理方法往往不足以去除这些持久污染物.
- 先进的氧化工艺 (AOP) 为微污染物降解提供了有前途的解决方案.
研究的目的:
- 开发和研究一种新的一氧化物 (CoO) 激活酸 (PAA) 系统,以有效地去除新出现的微污染物.
- 阐明反应性氧物种 (ROS) 生成的机制及其在污染物降解中的作用.
- 评估AOP中的CoO催化剂的稳定性和可重复使用性.
主要方法:
- 在中性条件下使用一氧化物 (CoO) 催化剂激活酸 (PAA).
- 产生反应性氧物种 (ROS) 的识别和量化,包括基激素,单片氧,有机激素和高价值物种.
- 通过电子转移机制降解新出现的微污染物.
- 密度函数理论 (DFT) 计算以支持反应机制.
- 通过多个反应周期评估催化剂的可重复使用性.
主要成果:
- CoO/PAA系统有效地激活了PAA,产生了多个ROS,包括基激素 (HO•),单片氧 (1O2),有机激素 (RO•) 和高价值 (Co(IV)).
- 有机基和高价值物种被确定为新兴微污染物通过电子转移降解的主要驱动因素.
- DFT计算证实了PAA在CoO表面的自发吸附,导致过氧键裂变和基因生成.
- CoO催化剂的结构变化最小,在多个处理周期中具有很高的可重复使用性.
结论:
- 新的CoO/PAA系统代表了一种有效的先进氧化工艺,用于去除水中的新出现的微污染物.
- 涉及异质和同质相的双激活机制提高了ROS生成和污染物降解效率.
- 催化剂的稳定性和可重复使用性使其成为水处理应用的有希望和可持续的方法.
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