氧化Fe转化诱导吸附的减少和增强Cr (VI) 的降解,由酸-铁酸铁共降
Hui Wang1, Fengping Liu2, Yankun Zhang3
1State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China; Beijing Key Laboratory of Water Resources & Environmental Engineering, China University of Geosciences, Beijing 100083, PR China.
Journal of hazardous materials
|August 25, 2024
概括
酸-铁共沉积物的有氧转化增强了它们对Cr6的解毒能力. 这一过程通过促进这些有机矿物联的结构变化,促进了有毒Cr (VI) 的减少.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 土壤科学 土壤科学
背景情况:
- 化物质-铁共沉积物是土壤和含水层中关键的有机矿物联体.
- 这些材料可以固定和排毒六价 (CrVI)).
- 在有氧条件下转化后,这些共同沉物的环境行为尚未得到充分理解.
研究的目的:
- 模拟酸 (HA) -Fe (III) 共同沉的有氧转化.
- 评估这种转化对的吸附和减少对环境的影响.
- 了解结构变化如何影响共沉积物处理Cr的能力.
主要方法:
- 模拟HA-Fe (III) 共同沉积物的有氧转化.
- 使用Cr(VI) 的吸附降解批量实验.
- 分析共沉积物结构及其对Cr (VI) 整治的影响.
主要成果:
- 氧化转化显著改变HA-Fe (III) 共沉积物结构,影响它们的Cr (VI) 结合和减少能力.
- 类似铁酸盐的共沉积物转化为晶体形式 (血石,甲石),减少表面积,但增强了Cr (VI) 的减少.
- 类似胺物质的 precipitates 显示Fe (III) 减少到Fe (II) 由HA,然后驱动Cr (VI) 减少.
结论:
- 氧化转化在提高HS-Fe (III) 共同沉积物的Cr (VI) 降解能力方面发挥着至关重要的作用.
- 结构演变决定了对Cr (VI) 的共同沉积物的环境功能.
- 这些发现表明,对于CrVI污染的场地,有可能开发现场修复剂.
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