从电子废物中通过直接从MoS2阴极启用的孕液中逐步放电回收黄金和银的高度选择性回收
Deshou Wang1, Yumeng Liang1, Yong Zeng1
1Key Laboratory of Green Utilization of Critical Non-metallic Mineral Resources of Ministry of Education, Wuhan University of Technology, Wuhan 430073, Hubei, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, Hubei Province 430070, China.
Journal of hazardous materials
|January 6, 2024
概括
这项研究开发了一种MoS2涂层的阴极,用于从废弃印刷电路板的液中选择性电沉积贵金属 (黄金和白银) 和铜. 这种方法实现了高回收率,并支持电子行业的循环经济.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 环境科学 环境科学
背景情况:
- 废弃印刷电路板 (WPCB) 含有比开采的矿石更高的贵金属和普通金属度.
- 从WPCB的水溶液中选择性地提取低度贵金属是具有挑战性的,因为它与铜等高度基础金属共同沉积.
- 开发有效的WPCB回收工艺对于环境和经济效益至关重要.
研究的目的:
- 开发一个阶段性电沉积方法,从WPCB的硫酸盐浸出溶液中选择性地回收贵金属 (Au,Ag) 和铜.
- 为了研究使用涂有二硫化 (MoS2) 的阴极 (MoS2/Ti) 来提高电沉积效率和选择性.
- 为了优化关键参数的逐步电解过程.
主要方法:
- 一个MoS2涂层的阴极 (MoS2/Ti) 的制造.
- 循序渐进的电沉积过程:第一步是固定电位 (0.6V) 的贵金属 (Au,Ag),第二步是恒定电流 (0.03A) 的铜 (Cu).
- 优化降解潜力,氨度 (NH3·H2O) 和硫酸硫酸盐度 (S2O32-).
- COMSOL 多物理模拟用于现场丰富机制的可视化和确认.
主要成果:
- 电极MoS2/Ti促进了黄金和白银的选择性电沉积,在第一步中实现了92.44%的Au和98.18%的Ag回收,而没有铜的共同沉积.
- 第二步在12小时内成功回收了100%的铜.
- 优化条件提高了逐步电沉积过程的效率和选择性.
- 科姆索尔的模拟证实了MoS2表面的贵金属复合物的现场丰富.
结论:
- 开发的MoS2/Ti阴极能够从WPCB的漏溶液中有效和选择性地逐步回收贵金属和铜.
- 这种电化学方法为WPCB回收提供了一个有希望的解决方案,为电子行业的闭环循环经济做出了贡献.
- 这些发现为设计可持续的金属回收技术提供了宝贵的见解.
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