硫酸攻击下的富含铁活性材料的化动力学:使用低场NMR放松计的现场方法
Ziyou Yu1, Rodrigo de Oliveira-Silva1, Everton Lucas Oliveira2
1M2S, cMACS, KU Leuven, Celestijnenlaan 200F, Leuven 3001, Belgium.
Analytical chemistry
|April 14, 2025
概括
质子核磁共振 (NMR) 放松计提供了一种新的现场方法,用于追踪酸中活性材料 (AAM) 释放的铁离子. 在AAM中较高的含量增强了对硫酸攻击的抵抗力.
科学领域:
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
- 物理化学 物理化学
背景情况:
- 富含铁的活性材料 (AAMs) 容易受到酸性攻击,影响其耐用性.
- 评估抗酸性的传统方法是现场的,耗时的,容易出错的.
- 实时监测铁离子 (Fe3+) 泄漏对于了解AAM降解动力学至关重要.
研究的目的:
- 开发和验证使用质子核磁共振 (NMR) 放松计来监测Fe3+离子度的现场方法.
- 量化测量硫酸中富含铁的AAMs中Fe3+离子的实时释放.
- 为了研究含量对富含铁的AAMs的抗酸性的影响.
主要方法:
- 使用质子核磁共振 (NMR) 放松计利用Fe3+离子的偏磁性质.
- 在质子放松率和Fe3+离子度之间进行了校准.
- 现场核磁共振技术被用来观察随着时间的推移,硫酸溶液中的AAMs的漏行为.
主要成果:
- 该研究成功地对Fe3+度的NMR放松率进行了校准,从而实现了实时定量监测.
- 现场核磁共振方法显示出高时间分辨率,允许对Fe3+释放的动态分析.
- 对于含有较低含量 (<20 mol %) 的富含铁的 AAM,较高的含量与较低的表面反应速率常数相关,表明更好的抗酸性.
结论:
- 质子NMR放松计提供了一种非破坏性,非侵入性和高效的现场技术,用于研究富含铁的AAMs上的酸攻击动力学.
- 这些发现强调了含量在增强AAM的硫酸耐药性方面的重要性.
- 这种基于NMR的方法补充了传统方法,并为材料降解机制提供了宝贵的见解.
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