在化学稳定后,通过加速老化系统的土壤长期稳定性的机制和影响因素
Jianli Jia1, Linying Yao1, Bing Xiao1
1School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, PR China.
Journal of hazardous materials
|June 23, 2024
概括
(Cr) 污染土壤的化学稳定降低了Cr (VI),但可能导致长期的不稳定性. 一个加速老化系统模拟了环境因素,揭示了稳定虽然最初是有效的,但随着时间的推移对土壤Cr稳定性构成风险.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 地质化学 地质化学
背景情况:
- 化学稳定是一种常见的 (Cr) 污染土壤修复方法,主要是通过将六价 (Cr(VI)) 减少为三价 (Cr(III)).
- 这种修复策略的长期有效性受到自然和人为环境过程的挑战,这些过程会影响长期的稳定性.
研究的目的:
- 建立一种方法来评估土壤中修复的长期有效性.
- 开发一种加速老化系统,模拟酸雨浸出和冷解周期,以评估的长期稳定性.
- 研究化学稳定后土壤物种化长期变化的机制和影响因素.
主要方法:
- 开发了一种加速老化系统,以模拟酸雨浸和融周期.
- 使用Metafix®对污染的土壤样本进行化学稳定.
- 利用包括X射线吸收近边缘结构 (XANES) 在内的技术分析了土壤物种化和性变化.
主要成果:
- 化学稳定显著减少了土壤Cr6和可浸的,Cr6在土壤中的去除率为89.70%.
- 尽管最初有效,但化学稳定加剧了土壤的不稳定性,在模拟老化过程中,可浸的增加.
- 加速老化表明,酸雨激活了Cr{III}并溶解了Cr{VI},而融周期主要影响有机物结合的 (OM-Cr).
结论:
- 化学稳定虽然短期有效,但会导致土壤中长期的不稳定.
- 酸雨的浸和老化时间是影响稳定的关键因素,冷-解周期加剧了酸雨的影响.
- 该研究提供了一种新的方法来评估化学稳定污染场所的长期性能和不稳定机制.
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