在受污染的田土壤中对Cu和Cd进行无机修改的固定机制在短期/长期内
Qing Liu1,2, Yuan Ding1,2, Yuqi Lai1,2
1College of Environment and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063, China.
Toxics
|February 23, 2024
概括
土壤修饰物如石灰,零价值铁,和attapulgite有效地减少污染土壤中可用的铜 (Cu) 和 (Cd). 这些修正案还有助于通过随着时间的推移形成无形氧化铁来稳定重金属.
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:
- 土壤被铜 (Cu) 和 (Cd) 等重金属污染给环境带来了重大风险.
- 了解金属的物种化和转移对于有效的整治策略至关重要.
- 土壤合性质的变化影响金属的流动性和生物可用性.
研究的目的:
- 为了研究土壤的合性特性如何影响Cu和Cd在修改处理后的物种化和转移.
- 评估石灰,零价值铁和attapulgite在固定Cu和Cd的短期和长期有效性.
- 为了澄清金属激活危险和受这些修正案影响的老化过程背后的机制.
主要方法:
- 污染的土壤样本用石灰 (L),零价值铁 (ZVI) 和attapulgite (ATP) 进行处理.
- 可用的Cu和Cd度是在治疗后6个月和12年测量的.
- 土壤和合物分析的重点是铁和氧化物分数和无形氧化铁含量的变化.
主要成果:
- 所有的修订都在短期内 (6个月) 显著减少了可用的Cu和Cd.
- 石灰没有显著的长期不动效应,而ZVI和ATP显示Cu和Cd在12年内持续不动.
- 无形氧化铁含量增加与Cu和Cd的强化固定相关,表明该分数的稳定.
结论:
- 土壤修饰,特别是ZVI和ATP,为污染土壤中的Cu和Cd固定提供了有效的长期解决方案.
- 无形氧化铁的形成在稳定重金属,减轻其生物利用性和转移方面发挥着关键作用.
- 修改选择和土壤的合性质是管理重金属污染和老化过程的关键因素.
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