在酸-酸系统中的吸附和脱附行为和机制
Cong Li1, Chao Xie1,2,3, Tianjiao Jiang1,3
1School of Nuclear Science and Technology, University of South China, Hengyang 421001, China.
Toxics
|March 27, 2024
概括
从核废物中提升的分离,使用酸中化中的SiPyR-N3树脂. 这种复合树脂具有较高的吸附能力和对的选择性,可有效回收.
科学领域:
- 核化学 核化学 核化学
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
背景情况:
- 从高水平液体废物 (HLLW) 中分离 (Ru) 是非常重要的,因为它的价值和对玻璃化的负面影响.
- 鲁的复杂化特性使其分离具有挑战性.
- 开发高效的吸附剂是核废物管理和资源回收的关键.
研究的目的:
- 在合成的SiPyR-N3复合物上研究的吸附和脱附特性.
- 探索在酸和酸-酸系统中的吸附机制.
- 评估SiPyR-N3在从HLLW中选择性去除的性能.
主要方法:
- 合成的SiPyR-N3 (弱基离子交换树脂与皮里丁的功能组).
- 在酸和酸-酸系统中研究了的吸附.
- 分析了吸附动力学 (伪二阶) 和同热量 (Langmuir).
- 使用FT-IR,XPS和UV-Vis光谱学的特征吸附机制.
- 评估了使用混合氨酸和酸溶液的脱吸效率.
主要成果:
- 与单独的酸相比,SiPyR-N3在酸-酸中的吸附能力增加了三倍.
- 在化-酸系统中,最大吸附能力达到45.6 mg/g.
- 观察到对其他金属离子 (SF ≈100) 的高吸附选择性.
- 吸附遵循伪二次动力学和兰格穆尔异热模型.
- 发现酸盐离子参与复杂化和吸附过程.
- 有效的脱吸 (92%的效率在328K) 是通过尿酸和酸混合物实现的.
结论:
- SiPyR-N3在化-酸介质中表现出优越的吸附性能,显著提高了分离效率.
- 树脂显示出优异的选择性和容量,使其成为从HLLW中回收的有希望的候选人.
- 了解酸盐离子在吸附机制中的作用,为优化分离过程提供了洞察力.
- 开发的脱吸法为吸附后的回收提供了一条有效的途径.
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