在回收过程中,Cd与 struvite 共同沉
Xingwen Lu1, Jiating Li1, Wang Xu2
1School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
Chemosphere
|November 4, 2023
概括
(Cd2+) 在回收过程中显著降低了斯特鲁维特的纯度. 它破坏了晶体的生长,形成无形化合物,并影响了废物流中的营养回收.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 水处理 处理水的方法
背景情况:
- 斯特鲁维特回收是废水中营养物质回收的关键过程.
- 是一种危险的重金属,经常存在于工业和城市废物流中.
- 了解 struvite 沉期间的金属封存对于工艺效率和安全至关重要.
研究的目的:
- 研究离子 (Cd2+) 对 struvite 的降水和纯度的影响.
- 阐明Cd2+在形成过程中与 struvite 相互作用的机制.
- 在Cd2+的存在下,描述 struvite 的结构和化学变化.
主要方法:
- 定量X射线衍射 (QXRD) 用于确定 struvite 的纯度.
- 扫描电子显微镜 (SEM) 用于表面形态分析.
- X射线光电子光谱 (XPS) 用于分析表面的化学组成和粘合.
主要成果:
- 斯特鲁维特的纯度从99.1%降至73.6%随着Cd2+度 (1500μM) 的增加.
- 由于Cd2+的存在,SEM揭示了粗的石头表面.
- XPS表示Cd2+主要与-OH和-PO4结合,形成与斯特鲁维特共同沉的无形Cd载体化合物.
结论:
- Cd2+ 抑制纯 struvite 晶体的生长,导致产品纯度降低.
- 无形的Cd和Mg载体相与斯特鲁维特一起形成,改变了沉物的组成.
- 这些发现突出了从Cd污染的废物流中矿回收的挑战.
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