Department of Civil and Environmental engineering, University of Delaware, Newark, DE 19711, United States.
Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19711, United States.
Sci Total Environ. 2017 Jul 15;590-591:809-817. doi: 10.1016/j.scitotenv.2017.03.061. Epub 2017 Mar 11.
The current study developed a rationalized method for the quantification and identification of engineered nanoparticles (ENPs) in wastewaters. A review of current literature revealed that overall, presently available methods focused on single ENP mostly and were applicable mainly to samples of low organic loadings or under well-controlled laboratory conditions. In the present research, procedures including dialysis for desalting and low-temperature oxidation for organic removal were used to pretreat samples of high organic loadings, specifically, municipal wastewater and sludge. SEM mapping technique identified the presence of nanoparticles, which was followed by ICP-OES quantification of different engineering nanoparticles in wastewater and sludge samples collected from two major regional municipal wastewater treatment plants. Results showed successful identification and quantification of nano-size titanium and zinc oxides from wastewater treatment plants studied. Concentration profile was mapped out for the wastewater treatment plants (WWTPs) using the method developed in this research. Results also showed an overall 80% and 68% removal of titanium and zinc by primary and secondary sludge particulates, respectively. Mass flux of engineered nanoparticles (ENPs) was also calculated to estimate the daily flow of engineered nanoparticles in the system.
本研究开发了一种合理化的方法，用于量化和识别废水中的工程纳米粒子（ENPs）。对现有文献的综述表明，目前可用的方法主要集中在单一的 ENP 上，主要适用于低有机负荷的样品或在良好控制的实验室条件下。在本研究中，包括脱盐的透析和去除有机物的低温氧化等程序被用于预处理高有机负荷的样品，特别是城市废水和污泥。SEM 映射技术识别出了纳米粒子的存在，随后通过 ICP-OES 对从两个主要地区性城市污水处理厂采集的废水和污泥样品中的不同工程纳米粒子进行了定量。结果表明，成功地从研究的污水处理厂中识别和定量了纳米级的钛和氧化锌。利用本研究中开发的方法，为污水处理厂（WWTP）绘制了浓度分布。结果还表明，初级和二级污泥颗粒分别对钛和锌的去除率达到了 80%和 68%。还计算了工程纳米粒子（ENPs）的质量通量，以估计系统中工程纳米粒子的日流量。
