氧化还原潜力模型用于指导土壤中多环芳的中度氧化
Yanping Ji1, Jiang Xu1, Lizhong Zhu1
1College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China.
Journal of hazardous materials
|April 28, 2024
概括
一个新的土壤氧化还原潜力 (Eh) 模型准确地预测了在现场化学氧化过程中污染物的去除,防止过量剂量和保护土壤健康. 这种方法优化了氧化剂的使用,以实现有效和可持续的土壤整治.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 环境化学环境化学
背景情况:
- 在现场化学氧化 (ISCO) 对于修复多环芳 (PAH) 等持久有机污染物至关重要.
- 目前的ISCO实践往往涉及大量氧化剂的应用,没有精确的模型,风险二级土壤损害过量,改变土壤有机物质和酸度.
- 预测和控制氧化还原潜力 (Eh) 对于有效的ISCO至关重要.
研究的目的:
- 建立土壤氧化还原潜力 (Eh) 模型,以量化氧化参数,土壤特性和污染物消除之间的关系.
- 系统地澄清氧化剂类型,剂量,土壤pH值和有机碳对土壤Eh的影响.
- 为污染土壤提供适度氧化策略,减少氧化剂消耗和二次损害.
主要方法:
- 开发并完善了一个土壤Eh模型,包括土壤质地和溶解的有机碳.
- 系统地研究了四种常见的氧化系统:KMnO,H,O,Fenton和硫酸盐.
- 使用12个实际受PAH污染的土壤样本和分析的氧化产品,验证了模型的准确性.
主要成果:
- 经过纳入土壤纹理和溶解有机碳后,精细化的Eh模型实现了高精度 (4-16%的相对误差).
- 确定了PAHs的临界氧化潜力 (COP),使得有针对性的整治成为可能.
- 证明PAH的氧化最常见于它们的COP,这表明增强微生物降解的途径.
结论:
- 已建立的Eh模型为ISCO中氧化剂选择和剂量控制提供了一个可行的策略,促进中度氧化.
- 这种方法最大限度地降低了与过度氧化和氧化剂残留相关的二次风险,保护了土壤的有机物质和结构.
- 以Eh模型为指导的中度氧化与随后的微生物降解相结合,为土壤整治和未来利用提供了一个有效的绿色战略.
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