的吸附通过分层的双氧化物:性能,结构相关的机制,和封存稳定性评估
Dong Zhang1, Zhishun Zhong2, Zilong Liu1
1Department of Environmental Science, College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, China.
Chemosphere
|February 8, 2024
概括
层状双氧化物 (LDHs) 显示了去除的巨大潜力. 在LDH中的同态替代增强了Cd吸附能力和稳定性,这对于废水处理和土壤整治至关重要.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 层状双氧化物 (LDH) 是重金属修复的有希望的.
- 异形替代是LDH中重金属吸附的关键机制,但其对性能和稳定性的影响尚未完全理解.
研究的目的:
- 为了合成和评估 (Cd) 吸附性能和稳定性的LDHs.
- 为了研究Cd修复中的等态置换的结构-属性关系.
主要方法:
- 合成具有不同结构的各种LDHs.
- 评估Cd吸附能力和稳定性,使用诸如同态置换分析等技术.
- 在各种条件下进行测试,包括不同的共存和环境矩阵.
主要成果:
- 双价阴离子类型显著影响Cd吸附能力和同态替代,遵循氧化物溶解度趋势.
- CaAl-LDH显示出高的Cd吸附能力 (625.0毫克g-1).
- 在不同的条件下,Mg2.9Cd0.1AlCl-LDH显示出最小的Cd出 (≤7.69%),表明其高稳定性.
结论:
- 同态置换对于增强LDHs中的Cd吸附和稳定性至关重要.
- 双价离子的类型和LDH的结构性质影响了Cd修复效率.
- 装有Cd的LDH具有很高的稳定性,使其适用于废水处理和土壤整治的实际应用.
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