铁在本托尼特泥中的阳极溶解机制
Pranav Vivek Kulkarni1, Anna Igual-Munoz1, Jean-Michel Sallese2
1EPFL-École Polytechnique Fédérale de Lausanne, Tribology and Interfacial Chemistry (TIC) Group, Lausanne, Switzerland.
概括
研究了与放射性废物处理相关的托尼特泥中的铁腐蚀. 较高的本托尼特度加速了铁的溶解,形成了酸性凝,影响了处置的安全性.
科学领域:
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
- 电化学 电化学 电化学
背景情况:
- 石对于放射性废物处理的安全性至关重要.
- 之前的研究集中在紧的本托尼特中对铁的腐蚀,而不是泥.
- 如果防护外套断裂,可以形成本托尼特泥,使钢铁暴露在水中.
研究的目的:
- 在托尼特泥中研究铁腐蚀.
- 了解腐蚀产品形成的机制.
- 评估本托尼特度对腐蚀的影响.
主要方法:
- 在纯铁上进行加速腐蚀实验.
- 电化学腐蚀技术 电化学腐蚀技术.
- 对本托尼特泥化学的分析 (pH 9-10).
主要成果:
- 铁的溶解与本托尼特泥的度增加.
- 一种酸性凝,由于电离子交换 (Fe2+换H+) 形成.
- 凝生长是由接口反应控制的,而不是扩散.
结论:
- 班托尼特泥中的铁腐蚀取决于度.
- 形成的酸性凝会影响处置环境.
- 了解凝形成是放射性废物仓库长期安全的关键.
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