在含有硫酸盐的系统中,二氧化碳涂层对纳米尺寸零价值铁在序列还原氧化过程中的作用
Quoc Bien Nguyen1, Cheolyong Kim2, Inseong Hwang1
1Department of Civil and Environmental Engineering, Pusan National University, Busandaehak-ro 63beon-gil 2, Geumjeong-gu, Busan 46241, Republic of Korea.
Journal of hazardous materials
|September 26, 2024
概括
一个新型的序列降解氧化工艺,使用涂有的纳米级零价值铁 (nZVI@SiO2) 和硫酸盐有效地矿化酸. 这种涂层提高了效率,并保护了颗粒,以便在地下水中持续清除污染物.
科学领域:
- 环境化学环境化学
- 纳米技术 纳米技术
- 水处理 处理水的方法
背景情况:
- 地下水中的反弹性有机化合物给环境带来了重大挑战.
- 传统的减少或氧化方法本身往往显示出完全矿化效率有限的效率.
- 纳米化零价值铁 (nZVI) 是有效的减少,但可能是不稳定的,容易产生副作用.
研究的目的:
- 开发和评估一个连续的降解-氧化过程,使用覆盖的nZVI (nZVI@SiO2) 和硫酸盐来增强反化合物的矿化.
- 研究SiO2涂层在提高nZVI的效率和稳定性方面的作用.
- 优化工艺,有效地去除酸及其转化产品.
主要方法:
- 使用了一种连续的工艺,将nZVI@SiO2降解与硫酸盐氧化相结合.
- 二被用作一种模型复杂化合物来评估过程的有效性.
- 分析了SiO2涂层对nZVI反应性,产品转化和颗粒稳定性的影响.
- 优化了工艺参数,以最大限度地提高污染物矿化.
主要成果:
- 序列的nZVI@SiO2/硫酸盐工艺显著增强了酸矿化,而不是单独的减少或氧化.
- nZVI@SiO2 快速将酸降解为氨酸,随后氨酸被硫酸盐持续氧化降解.
- SiO2涂层提高了酸转化为氨酸的效率,并通过受控的Fe (II) 释放延长了酸盐激活.
- 涂层的nZVI@SiO2颗粒表现出对地下水成分的优越稳定性,导致整体酸-氨酸矿化较高.
结论:
- 开发的使用nZVI@SiO2和硫酸盐的顺序降解氧化工艺为地下水中的反抗性有机污染物矿化提供了一种高度有效的方法.
- SiO2涂层对于提高nZVI在环境应用中的效率,稳定性和寿命至关重要.
- 这种方法为水处理中的先进氧化过程提供了一个有希望的策略.
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