从复杂的水矩阵中快速,选择性地提取银,采用金属有机框架/通过超临界CO2构建的寡合复合物
Tianwei Xue1, Li Peng1, Olga A Syzgantseva2
1College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, China.
Angewandte Chemie (International ed. in English)
|September 4, 2023
概括
研究人员开发了一种使用超临界二氧化碳的绿色方法,以创建金属有机框架 (MOF) /寡合物复合物,以有效地回收银离子. 这种新型材料迅速从废物流中去除银,超过了环境标准,并提供了抗菌的好处.
科学领域:
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
- 绿色化学 绿色化学
背景情况:
- 银是一种有价值但日益减少的资源,在工业废物流中发生了重大损失.
- 由于需求增加和供应有限,有效和环保的白银回收方法至关重要.
研究的目的:
- 开发一种可控制的绿色工艺,用于生产高度多孔的金属有机框架 (MOF) /寡合物复合材料.
- 评估这些复合材料对复杂矩阵中的银离子 (Ag+) 吸附和回收的有效性.
主要方法:
- 使用超临界二氧化碳 (ScCO2) 作为合成MOF/寡合物复合物的介质.
- 研究了MIL-127/Poly-o-phenylenediamine (PoPD) 复合物的Ag+吸附能力和去除效率.
- 采用理论模拟来理解Ag+复合的机制.
主要成果:
- 该MIL-127/PoPD复合材料表现出优异的Ag+吸附能力,并实现了>99%的去除效率.
- 在短短5分钟内实现了快速Ag+提取,使银度降低到0.1ppm以下.
- 在MOF内的空间排序的聚合物单元促进了对竞争离子的选择性Ag+复合.
结论:
- 开发的基于ScCO2的工艺为生产用于白银回收的MOF/寡合物复合材料提供了绿色和高效的途径.
- 该MIL-127/PoPD复合材料显示了银的环境修复和资源回收的巨大潜力.
- 复合材料能够将银离子减少到金属银的能力也赋予了宝贵的抗菌特性.
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