溶解土壤Pb通过热转化减少到含Pb的田
Yohey Hashimoto1, Kento Sonoda1, Yuki Nagao1
1Tokyo University of Agriculture and Technology, Japan.
Journal of hazardous materials
|June 3, 2023
概括
热处理通过将其转化为不太溶解的形式,有效地使土壤 (Pb) 固定不动. 将土壤加热到900°C有助于Pb-feldspar的形成,显著降低了的溶解性和提取性.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 土壤科学 土壤科学
背景情况:
- 土壤被 (Pb) 污染造成了严重的环境和健康风险.
- 热处理是一种有前途的修复策略,用于固定土壤中的重金属.
- 了解热处理期间的Pb物种变化对于有效的补救至关重要.
研究的目的:
- 在不同温度 (100-900°C) 进行热处理后,研究Pb在土壤中的可溶性.
- 使用X射线吸收细结构 (XAFS) 光谱学,将Pb溶解度与Pb物种变化的相关性.
- 为了阐明在土壤加热过程中Pb固定化的机制.
主要方法:
- 土壤样本在100°C至900°C的温度下进行热处理.
- 使用水和HCl提取方法评估了Pb溶解度.
- 使用X射线吸收细结构 (XAFS) 光谱分析了Pb的特异性.
- 对氧化铁的相变化进行了监测.
主要成果:
- 热处理后存在的Pb化学物种与Pb溶解度有很强的相关性.
- 石和土相关Pb的分解发生在300°C左右.
- 在900°C时观察到水和HCl可提取Pb的显著减少.
- 在900°C时,含有Pb的地形成达到土壤Pb总量的70%左右.
- 铁氧化物转化为血,对Pb物种的影响最小.
结论:
- 热处理有效地固定了土壤Pb,将其转化为不太溶解的矿物相.
- 的固定机制涉及不稳定的物种的分解,与富含Si-Al的液体的结合,以及在高温下形成Pb-feldspar类似的矿物质.
- 该研究提供了有关Pb在污染土壤中的热稳定性和转化途径的见解.
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