稀土元素在煤炭和煤炭燃烧副产品中的特异化:XANES和EXAFS研究
Brendan A Bishop1, Karthik Ramachandran Shivakumar2, Jamie Schmidt1
1Department of Earth Sciences, University of Regina. 3737 Wascana Parkway, Regina S4S 0A2, Saskatchewan, Canada.
Environmental science & technology
|July 30, 2024
概括
从煤炭燃烧副产品 (CCB) 中提取稀土元素 (REE) 是低碳经济的关键. 这项研究发现,在燃烧过程中,REE宿主阶段在很大程度上从煤炭转移到CCB,有助于有效的回收.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 过渡到低碳经济需要增加对稀土元素 (REE) 等关键矿物质的需求.
- 煤炭燃烧的副产品 (CCB) 正在成为可再生能源的潜在次要来源,通过利用废物促进循环经济.
- 关于控制从CCB中回收REE的因素,特别是它们的物种和发生方式的研究有限.
研究的目的:
- 调查煤炭及其相关的CCB中的伊 (REE的代理) 的物种化和局部结合环境.
- 了解燃烧过程中REE轴承相的转变.
- 为从CCB中开发高效和环保的REE回收流程提供信息.
主要方法:
- 基于同步的X射线吸收光谱学 (XAS) 用于分析REE物种化.
- 进行了扩展的X射线吸收细结构 (EXAFS) 和X射线吸收近边缘结构 (XANES) 分析.
- 线性组合拟合 (LCF) 用于识别具有REE的矿物相.
主要成果:
- 酸盐和酸盐矿物质被确定为煤炭和CCB中的主要REE承载阶段.
- 在燃烧过程中,REE宿主阶段的变化是最小的.
- 这些发现表明,REE主要从母煤转移到CCB.
结论:
- 在CCB中,REE宿主阶段在很大程度上是从原始煤中继承的,在燃烧过程中变化最小.
- 对REE物种化和发生的理解对于优化CCB的提取策略至关重要.
- 结果支持CCB作为关键稀土元素的可持续来源的可行性.
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