基于-CTAB的乳液的稳定性,光诱导的不稳定性和光交换性
Guguloth Naresh1, Roopesh Patali2, Ethayaraja Mani2
1Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
Langmuir : the ACS journal of surfaces and colloids
|August 18, 2025
概括
这项研究表明,紫外线如何使用特殊表面活性剂来破坏和重建稳定的油水乳液. 这种可光切换的工艺为石油回收和废水处理等应用提供了高效的控制.
科学领域:
- 合体和表面科学科学
- 材料化学 材料化学
- 物理化学 物理化学
背景情况:
- 与散装方法相比,刺激诱导的乳液不稳定提供了节能加工.
- 含有亚的表面活性剂使其具有光敏的界面特性.
- 高度稳定的乳液 (>45天) 很难以传统方式加工.
研究的目的:
- 为了证明n-decane-in-water乳液的光诱导不稳定和重建.
- 研究紫外线诱导脱的机制和动力学.
- 探索使用亚博烯表面活性剂的光交换性和控制乳液稳定性.
主要方法:
- 由含有阿佐的 cetyltrimethylammonium 化物 (Azo-CTAB) 稳定的 n-decane-in-water 乳液的配方.
- 暴露于紫外线 (UV) 和可见光以诱导和逆相分离.
- 滴滴凝聚和相位分离的动态分析.
- 系统变化紫外线光强度,电解质度和辅溶剂.
主要成果:
- 紫外线照明通过滴滴凝聚引发了快速相位分离,其速率常数比环境条件高5个数量级.
- 脱硫效率可以通过紫外线功率,电解质添加 (与NaCl的凝聚速度快4-5倍) 和挥发性共同溶剂进行调整.
- 通过暴露在可见光下,实现了原始乳液的重建,证明了可逆光交换性.
- 可逆过程在5-7个周期内稳定,滴滴特性没有显著变化.
结论:
- 含有亚的表面活性剂为光控制的乳液不稳定和重建提供了强大的工具.
- 亚-CTAB稳定乳液的可光切换性使其易于进行易于重复的乳液加工.
- 这项技术在需要动态乳液控制的应用中具有重大潜力,例如增强的石油回收和废水处理.
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