在减少和再氧化过程中,在受污染的土中调动合体和纳米粒子结合
Pengjie Hu1, Yu Zhang1, Jiajia Wang2
1State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Environmental science & technology
|June 21, 2023
概括
在土中的 (As) 与铁和有机物合物结合. 了解这些相互作用是管理的关键.
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:
- (As) 与状颗粒的结合影响了其在土壤-大米系统中的运输和可用性.
- 有限的知识存在于粒子束的As大小分布和米土壤中的组成,特别是在不断变化的氧化还原条件下.
研究的目的:
- 为了研究在小米土壤中的土壤减少和再氧化过程中颗粒结合的调动.
- 为了确定粒子结合的主要载体和尺寸分数.
- 了解铁和有机物质在结合中的作用.
主要方法:
- 化四个被A污染的土,具有明显的地质化学特性.
- 传输电子显微镜-能量分散光谱 (TEM-EDS) 用于元素分析.
- 不对称的流量场流量分成 (AF4) 用于尺寸分布分析.
主要成果:
- 有机物 (OM) 稳定型体铁,可能是 (氧) 氧化物-粘土复合物,被确定为主要的载体.
- 体主要与两个大小分数有关:0.3-40 kDa和>130 kDa.
- 土壤的减少释放了两个分数中的As,而再氧化导致了快速沉积,与溶液铁的变化有关.
- 作为度与纳米尺度 (0.3-40 kDa) 的Fe和OM正相关,具有pH依赖关系.
结论:
- 纳米铁-有机物-相互作用在米土壤地化学循环中至关重要.
- 了解尺寸解析颗粒结合对于预测其命运和在米环境中的运输至关重要.
- 氧化还原条件显著影响粒子结合的调动和沉积.
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