在硫化-再氧化过程中,化对铁化转化和相关的行为的影响
Kun Gao1, Xudong Bai1, Meiling Yin2
1College of Chemistry and Chemical Engineering, Shantou University, Shantou 515063, China.
Journal of hazardous materials
|March 14, 2026
概括
在大米土壤中添加加化会减少 (As) 的释放,通过抑制铁的减少和促进As的固定. 这项研究揭示了Mn Mn.
科学领域:
- 环境地质化学环境地质化学
- 土壤科学 土壤科学
- 生物地质化学生物地质化学
背景情况:
- (As) 在土中的命运是由铁 (Fe) 和硫 (S) 在氧化还原波动下循环控制的.
- (Mn) 与铁酸盐共存,影响Fe的地化学和As的行为,但其在硫化生成和As在动态氧化还原条件下的命运中的作用尚不清楚.
研究的目的:
- 在氧化还原动态条件下,研究化对铁化转化,硫化生成和As固定化的作用.
- 阐明控制在米土壤中的Fe-S-Mn系统中的As行为机制.
主要方法:
- 批量实验模拟在米土壤中的氧化还原动态条件.
- 地化学和矿物学分析以追踪Fe,S,Mn和As的分化和转化.
主要成果:
- 在低硫酸盐的条件下,铁化物转化为磁石,勒皮多克罗石和马基纳石,As释放最小.
- 高硫酸盐负载导致铁化物转化为硫化铁,释放了19.37-33.14%的化As,其中50.74-57.43%转化为残留形式.
- 兴奋剂的Mn抑制了化的减少,抑制了无氧时的As释放,促进了麦克纳石的形成,并增加了残留的As.
- 过渡到氧条件导致Fe (II) 和As (III) 的重新氧化,由新的Fe (III) 氧化物重新固定As,由Mn (III) 种子促进.
结论:
- 在米土壤中的氧化还原动态条件下,化在减轻铁酸盐从铁酸盐释放的过程中起着至关重要的作用.
- 通过促进硫化物形成和促进再氧化和再沉过程来增强As固定.
- 这些发现为Fe-S-Mn-As地化学提供了关键的见解,并为污染土壤中的As修复策略提供了信息.
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