Department of Materials Science and Engineering, National University of Singapore , 117575, Singapore.
ACS Appl Mater Interfaces. 2017 Oct 25;9(42):36772-36782. doi: 10.1021/acsami.7b10549. Epub 2017 Oct 10.
Wastewater contaminated with heavy metals is a worldwide concern due to the toxicity to human and animals. The current study presents an incorporation of adsorption and low-field dynamic magnetic separation technique for the treatment of heavy-metal-contaminated water. The key components are the eco-fabricated magnetic filter with mesh architectures (constituted of a soft magnetic material (Ni,Zn)FeO) and poly(acrylic acid) (PAA)-coated quasi-superparamagnetic FeO nanoparticles (NPs). PAA-coated FeO NPs possess high adsorption capacity of heavy metal ions including Pb, Ni, Co, and Cu and can be easily regenerated after the adjustment of pH. Moreover, magnetic mesh filter has shown excellent collection ability of quasi-superparamagnetic particles under a magnetic field as low as 0.7 kOe (0.07 T) and can easily release these particles during ultrasonic washing when small magnets are removed. In the end, after one filtration process, the heavy metal concentration can be significantly decreased from 1.0 mg L to below the drinking water standard recommended by the World Health Organization (e.g., less than 0.01 mg L for Pb). Overall, a proof-of-concept adsorption and subsequent low-field dynamic separation technique is demonstrated as an economical and efficient route for heavy metal removal from wastewater.
受重金属污染的废水是一个全球性的关注点，因为其对人类和动物都具有毒性。本研究提出了一种将吸附和低场动态磁分离技术结合起来处理重金属污染水的方法。关键组件是具有网状结构的生态制造磁性过滤器（由软磁材料（Ni，Zn）FeO 组成）和聚（丙烯酸）（PAA）涂覆的类超顺磁 FeO 纳米颗粒（NPs）。PAA 涂覆的 FeO NPs 对重金属离子（包括 Pb、Ni、Co 和 Cu）具有高吸附容量，并且可以在 pH 值调整后很容易地再生。此外，磁性滤网在低至 0.7 kOe（0.07 T）的磁场下显示出对类超顺磁颗粒的优异收集能力，并且当去除小磁铁时，在超声清洗过程中可以很容易地释放这些颗粒。最后，经过一次过滤过程，重金属浓度可以从 1.0 mg/L 显著降低到世界卫生组织（WHO）推荐的饮用水标准以下（例如，Pb 的浓度小于 0.01 mg/L）。总的来说，吸附和随后的低场动态分离技术的概念验证证明了这是一种从废水中去除重金属的经济有效的方法。
