使用双功能氨基表面活性剂的粘土颗粒的泡浮动
Cyril Micheau1, Yuki Ueda1, Ryuhei Motokawa1
1Materials Sciences Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
Langmuir : the ACS journal of surfaces and colloids
|July 28, 2023
概括
这项研究揭示了使用双功能表面活性剂的粘土漂浮中的pH依赖机制. 最佳的粘土提取在酸性和中性条件下发生,在不同的pH值范围内观察到不同的过程,用于环境修复.
科学领域:
- 环境科学 环境科学
- 合体和表面化学
- 材料科学 材料科学 材料科学
背景情况:
- 粘土漂浮对于从污染的土壤和地下水中去除重金属和放射性核化物至关重要.
- 粘土可以作为吸附剂和除泡剂,但它们与浮动中的表面活性剂的相互作用尚未完全理解.
- 了解这些相互作用是优化环境修复过程的关键.
研究的目的:
- 为了研究粘土浮动的pH依赖机制,使用双功能氨基聚乙化表面活性剂.
- 阐明粘土和表面活性剂在泡生成和稳定性中的分子相互作用的作用.
- 确定pH值如何影响粘土提取效率,并确定不同的漂浮过程.
主要方法:
- 采用双功能氨基聚氧化表面活性剂用于粘土收集和发泡.
- 分析了散装和泡阶段,以了解不同pH条件下的浮动机制.
- 采用电泳测量,动态光散射,小角度中子散射和图像分析来研究静电相互作用和多尺度结构.
主要成果:
- 粘土提取效率严重依赖于pH值.
- 在酸性 (pH < 6) 和中性 (pH 6-10) 条件下,粘土的界面回收几乎达到100%.
- 在性条件下 (pH>10) 观察到负面界面恢复,表明表面活性剂泡分离.
结论:
- 根据pH值确定了三种不同的漂浮机制:表面活性剂泡分化 (pH>10),粘土颗粒泡漂浮 (pH6-10),以及颗粒泡漂浮 (pH<6).
- 静电相互作用和多尺度结构显著影响粘土提取行为.
- 这些发现为优化环境修复应用中的粘土漂浮提供了洞察力.
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