红色泥基粘合剂中的Cr (VI) /Cr (III) 固定机制:从Cr-S-Fe相互作用和水化凝结构演变中的洞察力
Xingzhang Guo1, Haolong Zhang1, Zhaofeng Li1
1State Key Laboratory for Tunnel Engineering, Shandong University, Jinan, Shandong 250061, China; Institute of Geotechnical and Underground Engineering, Shandong University, Jinan, Shandong 250061, China; Solid Waste Recycling Technology Innovation Center of Shandong Province, Jinan, Shandong 250098, China.
Journal of hazardous materials
|November 7, 2025
概括
一种新型的粘合剂有效地固定了污染土壤中的 (Cr),使漏度降低了99%以上. 这种RGCD粘合剂使用红色的泥和工业副产品,为环境中污染的补救提供了一个有希望的解决方案.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
背景情况:
- 工业活动造成的污染对环境构成重大风险.
- 有效的稳定和固化方法对于管理污染土壤至关重要.
研究的目的:
- 开发和评估一种用于稳定/固化的新型RGCD (红色泥土颗粒高炉渣-碳化物渣-脱硫石膏) 粘合剂.
- 对Cr (VI) 和Cr (III) 两种粘合剂的固定机制和效率进行调查.
主要方法:
- 使用工业副产品合成RGCD粘合剂.
- 漂水试验以确定的度和固定效率.
- 动力建模 (伪二阶) 用于描述固定化过程.
- 化学分析 (例如29Si MAS NMR) 来阐明固定机制.
主要成果:
- 在0.25%重量%的剂量下,RGCD粘合剂实现了超过99%的Cr (VI) 和Cr (III) 固定效率.
- 即使在较高的1.00%Cr剂量下,也保持了高的固定效率 (>98%).
- 粘合剂中的低价值硫和反应性Fe2+将Cr (VI) 降低到Cr (III).
- ) 作为CaCrO4沉物固定或纳入;) 形成Fe-Cr氧化物或被替换成C-A-S-H凝.
结论:
- 在污染的土壤中,RGCD粘合剂在固定方面表现出色.
- 粘合剂的还原能力和稳定的沉/凝的形成有助于有效的封存.
- 高聚合C-(A) -S-H凝增强了的固定,尽管高度可以阻碍凝的形成.
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