Removal of oxide nanoparticles in a model wastewater treatment plant: Influence of agglomeration and surfactants on clearing efficiency
Removal of oxide nanoparticles in a model wastewater treatment plant: Influence of agglomeration and surfactants on clearing efficiency
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DOI：
10.1021/es800091f
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发表时间：
2008-08-01
影响因子：
11.4
通讯作者：
Stark, Wendelin J.
中科院分区：
文献类型：
--
作者：
Limbach, Ludwig K.;Bereiter, Robert;Stark, Wendelin J.
工程纳米颗粒的产量迅速增加，产生了从工业和公共废水流中去除颗粒的需求。鉴于越来越多的长期持久性和证据表明特定纳米颗粒具有相当大的生态毒性，有效的去除尤为重要。目前的工作调查使用一个模型污水处理厂去除氧化物纳米颗粒。虽然大多数纳米颗粒可以通过粘附在清除污泥上被捕获，但很大一部分工程纳米颗粒逃脱了污水厂的清除系统，并且在模型厂的出口流中发现高达6wt %的模型化合物氧化铈。我们的研究表明，表面电荷和分散稳定表面活性剂的添加对纳米颗粒衍生产品的制备有重要影响。对废水流中氧化纳米颗粒团聚的详细研究表明，颗粒在清除（污泥中细菌的吸附）方面具有很高的稳定性。这一意想不到的发现表明，有必要更详细地研究纳米颗粒的清除，并证明在不断变化的清除污泥环境中，溶解物质与纳米颗粒之间的复杂相互作用。
The rapidly increasing production of engineered nanoparticles has created a demand for particle removal from industrial and communal wastewater streams. Efficient removal is particularly important in view of increasing long-term persistence and evidence for considerable ecotoxicity of specific nanoparticles. The present work investigates the use of a model wastewater treatment plant for removal of oxide nanoparticles. While a majority of the nanoparticles could be captured through adhesionto clearing sludge, a significant fraction of the engineered nanoparticles escaped the wastewater plant's clearing system, and up to 6 wt % of the model compound cerium oxide was found in the exit stream of the model plant. Our study demonstrates a significant influence of surface charge and the addition of dispersion stabilizing surfactants as routinely used in the preparation of nanoparticle derived products. A detailed investigation on the agglomeration of oxide nanoparticles in wastewater streams revealed a high stabilization of the particles against clearance (adsorption on the bacteria from the sludge). This unexpected finding suggests a need to investigate nanciparticle clearance in more detail and demonstrates the complex interactions between dissolved species and the nanoparticles within the continuously changing environment of the clearing sludge.