电凝中Zn电极的阳极溶解和被动化:尿素度和化物诱导腐蚀的影响
Wafa Atba1, Mouna Cherifi1, Kamilia Moussaoui2
1Laboratory of Water Treatment and Valorization of Industrial Wastes, Badji Mokhtar-Annaba University, Annaba, Algeria.
概括
电极通过促进凝血,有效地处理废水中的尿素. 优化电流密度,pH值和度平衡溶解和被动化,以有效地去除污染物.
科学领域:
- 电化学 电化学 电化学
- 环境工程 环境工程
- 材料科学 材料科学 材料科学
背景情况:
- 电极被用作废水处理的牺牲阳极.
- 废水中的尿素可以导致离子凝结,但也会导致电极被动和腐蚀.
- 优化电化学处理需要了解电极的行为.
研究的目的:
- 用电极调查影响尿素去除的操作参数.
- 分析电极的电化学行为和表面变化.
- 为了确定有效的尿素处理的最佳条件,并尽量减少被动化.
主要方法:
- 电化学阻抗光谱学 (EIS) 是一种电化学阻抗光谱技术.
- 潜在动力学极化 (PDP) 是一种
- 循环电压计是循环电压计.
- 扫描电子显微镜使用能量分散光谱学 (SEM-EDS).
- 在X射线衍射 (XRD) 中.
主要成果:
- 尿素去除的最佳条件是:22 mA/cm2,pH为10,NaCl为25 mmol/L,尿素为20 mmol/L.
- 实现了12 mmol/L的尿素去除 (91 mg/L的 Zn 溶解,110%的法拉达效率).
- 通过氧化的形成观察到被动化,由XRD和SEM-EDS证实,限制溶解.
结论:
- 电极被动化 (ZnO形成) 和腐蚀是电极性能的关键因素.
- pH,化物和尿素度显著影响的腐蚀和溶解.
- 平衡溶解和被动化是优化污染物的电化学处理的关键.
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