红泥/钢基地质聚合物的制备和固定机制,用于固化/稳定Pb污染土壤
1Shandong Hi-Speed Engineering Test Co., Ltd., Jinan 250098, China.
Materials (Basel, Switzerland)
|July 13, 2024
概括
一种新型的红色泥/钢渣地质聚合物有效地使污染土壤中的 (Pb) 不动. 这种绿色水泥材料为土壤整治提供了低碳的解决方案,实现了显著的Pb稳定和提高土壤强度.
科学领域:
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
- 地质化学 地质化学
背景情况:
- 土壤中的 (Pb) 污染对环境和健康构成重大风险.
- 使用普通波特兰水泥 (OPC) 的传统土壤整治方法对生态和气候产生不利影响.
- 迫切需要可持续的低碳替代品来固定土壤中的重金属.
研究的目的:
- 设计和评估一种基于红泥/钢 (RM/SS) 的新型地质聚合物,用于污染土壤的固化和稳定.
- 优化RM/SS地质聚合物的制备条件,以获得最大的不受限制的压力强度 (UCS) 和Pb固定效率.
- 阐明开发的地质聚合物的微结构特征和Pb固定机制.
主要方法:
- 盒子-Behnken设计 (BBD) 用于响应表面建模,以优化地质聚合物制备.
- 使用X射线衍射测量,里埃变换红外光谱学,扫描电子显微镜和X射线光电子光谱学进行材料表征.
- 评估固化土壤样本的不受限制的压力强度 (UCS) 和Pb固定效率.
主要成果:
- 确定了最佳地质聚合物制备条件:液体固体比为0.76,RM质量分数为79.82%,活性化剂模量为1.21.
- 在最佳条件下,最大实现的UCS为3.42 MPa,Pb固定效率为71.95%.
- 识别的水化产品包括酸水合物,酸水合物和尼科伊特,有助于提高土壤强度和结构完整性.
结论:
- 开发的RM/SS地质聚合物是一种有希望的低碳材料,用于稳定受Pb污染的土壤.
- 固定主要通过将格子纳入地质聚合物结构 (Si-O-Pb,Al-O-Pb) 和物理封装来发生.
- 地质聚合物有效地增强了土壤的机械性能,同时使危险的重金属不移动.
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