从水性酸性废物溶液中回收和的"两步"电化学方法
Rahul Agarwal1,2, Jayashree S Gamare2, Chiranjit Nandi3
1Homi Bhabha National Institute, Mumbai 400 094, India.
Inorganic chemistry
|January 18, 2024
概括
一种新的两步电化学方法有效地从酸性废物溶液中回收 (Pu) 和 (U). 这种简化过程避免了二次废物产生,并为核燃料再加工提供了高回收率.
科学领域:
- 核化学 核化学 核化学
- 电化学 电化学 电化学
- 废物管理 废物管理
背景情况:
- 核燃料的化学质量控制产生含有 (Pu) 和 (U) 的酸性水性废物.
- 有效的和的回收对于放射性废物整治至关重要.
- 现有的回收方法很复杂,涉及化学氧化剂/减少剂,并产生二次废物.
研究的目的:
- 开发一种新的,简化的电化学方法,从酸性水性废物中回收和.
- 在存在各种金属杂质的情况下有效分离和.
- 为传统的,繁的回收方法提供可行的替代方案.
主要方法:
- 一个两步的批量电解过程,使用白金带电极.
- 步骤1:在0.1V的电压下将PuO2^2+减少为Pu^3+而不是Ag/AgCl/3M KCl,然后进行沉.
- 步骤2:在 -0.35 V 与 Ag/AgCl/3 M KCl 相比,将 UO2^2+ 减少为 U^4+ ,然后进行沉.
主要成果:
- 实现了高回收率:为97.8%,为99.1%.
- 成功地将和从金属杂质 (Fe, Cr, Mn, Cd, Al, Ni, Co, Zn, Mg) 中分离出来.
- 产生的K2 (K0.5Pu0.5) (SO4) 2和K2 (K0.67U0.33) (SO4) 2的纯沉物,产生没有Pu和U的废物溶液.
结论:
- 这种新的两步电化学方法为和的回收提供了操作简单性和高提取效率.
- 这种方法有效地修复放射性酸性水性废物,最大限度地减少二次废物产生.
- 该过程适合远程处理,与传统技术相比显著改进.
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