从电子垃圾中有效回收黄金和铜,采用选择性沉
Abhijit Nag1, Mukesh K Singh1, Carole A Morrison1
1EaStCHEM School of Chemistry, University of Edinburgh, EH9 3FJ, Edinburgh, UK.
Angewandte Chemie (International ed. in English)
|August 18, 2023
概括
这项研究引入了新的沉方法,可以从电子废物中选择性地回收黄金和铜,避免使用有机溶剂. 这些可持续技术提供了有效的金属回收利用,这对循环经济至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 环境化学环境化学
- 金工程 金工程 金工程
背景情况:
- 电子废物 (电子废物) 的回收对于循环经济和净零目标至关重要.
- 电子废物金属回收的传统溶剂提取方法通常依赖于有机溶剂.
- 开发选择性和可持续的沉过程对于高效的金属净化至关重要.
研究的目的:
- 开发新的选择性沉方法,从电子废物中回收黄金和铜.
- 用更可持续的替代品取代传统的基于有机溶剂的工艺.
- 为了证明这些方法在实际电子废物组件上的有效性.
主要方法:
- 在盐酸溶液中使用三酸氧化物 (TPPO) 选择性沉黄金.
- 使用2,3-pyrazinedicarboxylic酸 (2,3-PDCA) 选择性沉铜.
- 调酸度用于多种金属 (Au, Zn, Fe) 的受控沉.
主要成果:
- 选择性沉的黄金形式为[(TPPO) 4(H5O2) ]][AuCl4].
- 选择性沉的铜形式为[Cu(2,3-PDCA-H) 2) n·2n(H2O).
- 从电子废物连接针中获得99.5%的Au和98.5%的Cu回收.
结论:
- 开发的沉方法对于从电子废物中回收黄金和铜具有高度的选择性和效率.
- 这些工艺为传统的溶剂提取提供了可持续的替代方案,避免使用有机溶剂.
- 沉物的简单操作和可重复使用性表明电子废物净化具有重要的工业潜力.
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