ITODYS-Interfaces, Traitements, Organisation et Dynamique des Systèmes, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7086, 75013 Paris, France.
CEA-Université Paris-Saclay, Institut des Sciences du Vivant Joliot-Curie, Service de Chimie Bioorganique et de Marquage, Bât. 547, 91191 Gif-sur-Yvette, France.
J Nanosci Nanotechnol. 2019 Aug 1;19(8):4911-4919. doi: 10.1166/jnn.2019.16804.
Environmental pollution caused by heavy metals constitutes a serious public health problem. In the case of uranium depletion, amidoxime groups are important because of their high affinity for uranium(VI). New series of bis(amidoxime)s with catechol-derived anchor groups were tested (b-AMD-1 and b-AMD-2). The catechol groups were designed to bind to the surface of maghemite nanoparticles (MNPs), and two nanohybrid devices MNP-b-AMD-1 and MNP-b-AMD-2 were obtained. This strategy makes for efficient removal of U(VI) via its complexation with the bis(amidoxime)s (b-AMD) and also its extraction from aqueous solution by magnetic harvesting of the MNPs. The assynthesized and b-AMD-grafted MNPs were characterized by several techniques: X-ray diffraction (XRD), high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM), X-ray photoelectron spectrophotometry (XPS), thermal analysis (TG/DTA) and Fourier transform infrared spectroscopy (FTIR). Sorption tests were run at pH 6.5, which corresponds to the highest affinity and selectivity of b-AMD for U(VI). After magnetic separation, the chelation ability and the selectivity of MNP-b-AMD-1 and MNP-b-AMD-2 towards U(VI) were evaluated by measuring the residual U(VI) concentration in the supernatant by inductively coupled plasma-mass spectrometry (ICP-MS). The data were plotted according to the Langmuir and Freundlich isotherms; the maximal sorption capacity (qmax) was 29 and 60 mg U g-1 for MNP-b-AMD-1 and MNP-b-AMD-2, respectively. This confirms that bis(amidoxime) groups are good candidates for uranium depletion of aqueous solution.
重金属造成的环境污染构成了严重的公共卫生问题。在铀耗尽的情况下，偕胺肟基团因其对铀(VI)的高亲和力而变得尤为重要。本文测试了一系列带有儿茶酚衍生锚基的新型双(偕胺肟)s（b-AMD-1 和 b-AMD-2）。儿茶酚基团旨在与磁铁矿纳米颗粒（MNPs）的表面结合，得到两种纳米杂化装置 MNP-b-AMD-1 和 MNP-b-AMD-2。这种策略通过双(偕胺肟)(b-AMD)与铀(VI)的络合作用以及通过 MNPs 的磁性回收从水溶液中提取铀(VI)，实现了铀(VI)的有效去除。通过几种技术对合成的和接枝 b-AMD 的 MNPs 进行了表征：X 射线衍射(XRD)、高角度环形暗场(HAADF)扫描透射电子显微镜(STEM)、X 射线光电子能谱(XPS)、热分析(TG/DTA)和傅里叶变换红外光谱(FTIR)。在 pH 6.5 下进行了吸附实验，这对应于 b-AMD 对 U(VI)的最高亲和力和选择性。在磁性分离后，通过电感耦合等离子体质谱(ICP-MS)测量上清液中残留的 U(VI)浓度，评估了 MNP-b-AMD-1 和 MNP-b-AMD-2 对 U(VI)的螯合能力和选择性。数据根据 Langmuir 和 Freundlich 等温线绘制；MNP-b-AMD-1 和 MNP-b-AMD-2 的最大吸附容量(qmax)分别为 29 和 60mg U g-1。这证实了偕胺肟基团是从水溶液中去除铀的良好候选物。
