Facultad de Química y Biología, Universidad de Santiago de Chile, Av. B. O'Higgins, 363, Santiago, Chile.
Center for the Development of Nanoscience and Nanotechnology, CEDENNA, 9170124, Santiago, Chile.
Ecotoxicol Environ Saf. 2017 Nov;145:69-77. doi: 10.1016/j.ecoenv.2017.07.004. Epub 2017 Jul 11.
The application of iron nanoparticles (FeNPs) to the removal of various pollutants has received wide attention over the last few decades. A synthesis alternative to obtain these nanoparticles without using harmful chemical reagents, such as NaBH, is the use of extracts from different natural sources that allow a lesser degree of agglomeration, in a process known as green synthesis. In this study, FeNPs were synthesized by 'green' (hereafter, BB-Fe NPs) and 'chemical' (hereafter, nZVI) methods. Extracts of leaves and blueberry shoots (Vaccinium corymbosum) were used as reducing agents for FeCl·6HO solution in the green synthesis method. FeNPs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), electrophoretic migration, Brunauer-Emmett-Teller (BET) surface area analysis and X-ray diffraction (XRD) and evaluated for the removal of As(V) from aqueous systems. In both synthesis methods, XRD analysis confirmed the presence of the different kinds of iron nanoparticles. SEM analysis showed that the average size of BB-Fe NPs was 52.4nm and that a variety of nanoparticles of different forms and associated structures, such as lepidocrocite, magnetite, and nZVI, were present, while the dimensions of nZVI were 80.2nm. Comparatively significant differences regarding the electrophoretic mobility were found between both materials pre- and post-sorption of As(V). The velocity of As(V) removal by BB-Fe NPs was slower than that by nZVI, reaching equilibrium at 120min compared to 60min for nZVI. The removal kinetics of As(V) were adequately described by the pseudo-second-order kinetic model, and the maximum adsorbed amounts of this analyte are in close accordance with the experimental results. The Langmuir-Freundlich model is in good agreement with our experimental data, where the sorption capacity of nZVI and BB-Fe NPs was found to be 52.23 ± 6.06 and 50.40 ± 5.90 (mg·g), respectively. The use of leaves of Vaccinium corymbosum affords an easy-to-synthesize, low-cost, and eco-friendly material with capabilities similar to nZVI. BB-Fe NPs are promising for arsenic remediation, which has emerged as a new alternative for water purification and sanitation.
铁纳米粒子 (FeNPs) 在去除各种污染物方面的应用在过去几十年中受到了广泛关注。一种替代方法是使用不同天然来源的提取物，而不是使用有害化学试剂（如 NaBH）来合成这些纳米粒子，这种方法称为绿色合成。在这项研究中，通过“绿色”（以下简称 BB-Fe NPs）和“化学”（以下简称 nZVI）方法合成了 FeNPs。绿色合成方法中，使用蓝莓叶和嫩枝（Vaccinium corymbosum）提取物作为还原剂，将 FeCl·6HO 溶液还原为 FeNPs。通过透射电子显微镜 (TEM)、扫描电子显微镜 (SEM)、电泳迁移、Brunauer-Emmett-Teller (BET) 表面积分析和 X 射线衍射 (XRD) 对 FeNPs 进行了表征，并评估了它们从水溶液中去除 As(V) 的能力。在这两种合成方法中，XRD 分析均证实了不同种类的铁纳米粒子的存在。SEM 分析表明，BB-Fe NPs 的平均粒径为 52.4nm，存在各种不同形态和结构的纳米粒子，如针铁矿、磁铁矿和 nZVI，而 nZVI 的尺寸为 80.2nm。比较两种材料在吸附 As(V)前后的电泳迁移率，发现存在显著差异。BB-Fe NPs 去除 As(V)的速度比 nZVI 慢，达到平衡的时间为 120min，而 nZVI 则为 60min。As(V)的去除动力学很好地符合准二级动力学模型，该模型的最大吸附量与实验结果非常吻合。Langmuir-Freundlich 模型与我们的实验数据吻合较好，其中 nZVI 和 BB-Fe NPs 的吸附容量分别为 52.23±6.06 和 50.40±5.90(mg·g)。使用蓝莓叶作为原料可以制备出一种合成简单、成本低、环保的材料，其性能与 nZVI 相似。BB-Fe NPs 是一种很有前途的砷修复材料，为水净化和卫生提供了新的选择。
