2024年2月常州大学低碳清洁能源与安全高效燃烧科研团队孙运兰教授课题组陈九玉博士在Journal of Environmental Chemical Engineering期刊发表了题为“Bimetal ZIFs-derived Cu0 embedded in nitrogen-doped carbon framework activation of molecular oxygen for efficient iodide elimination”的研究论文。
放射性碘作为放射性核素之一，其释放到环境中，可对生态环境造成放射性污染，也会因衰变释放β和γ射线对人体健康造成长期威胁，甚至致畸、致癌。因此，在核能利用期间有效去除放射性碘不仅有利于核工业的可持续发展，更是保护公众健康的必要措施。本文以双金属CuxZn1-x-ZIFs为前驱体，在氮气气氛下高温碳化衍生出氮掺杂碳基体嵌入纳米零价铜复合材料（CuxZn1−x@NC），初步探索了其对模拟废水中碘离子的去除性能。CuxZn1−x@NC复合材料的理化性质及微结构表征分析结果表明，通过调节前驱体中Cu/Zn摩尔比可以调控材料的形貌、Cu0含量以及比表面积等。静态吸附实验结果表明，CuxZn1−x@NC复合材料在pH = 3时的吸附量高达235.5 mg g−1，并且具有较快的吸附动力学和高吸附选择性。同时，CuxZn1−x@NC表现出优异的再生与重复利用性能，再生材料对碘离子的吸附量是原始材料的~2倍。通过对吸附前后再生材料的表征分析，再生CuxZn1−x@NC对碘离子的去除机理除形成 I-C 共价键外，还发生纳米零价铜的类芬顿反应生成Cu(I)、Cu(II)以及活性氧物质（H2O2、-OH等），使得I-被Cu(I)捕捉并被活性氧氧化，氧化产物（IO3-）进一步被Cu(II)吸附。本研究结果证实，纳米零价铜基材料对碘离子的“吸附-氧化”协同作用机制是一种增效去除水体中放射性碘的有效途径。
该论文第一作者是陈九玉博士，该成果为南京理工大学和常州大学合作成果，南京理工大学杨毅教授为通讯作者，该研究成果得到了国家自然科学基金面上项目资助！
英文摘要：
Effectively removing radioiodine from radioactive wastewater is of great significance for the environment and human health. In this work, nitrogen-doped carbon matrix embedded zero-valent copper (CuxZn1-x@NC) nanocomposites was successfully prepared from copper-zinc bimetal zeolitic imidazole frameworks precursors (CuxZn1-x-ZIFs) through a pyrolysis method and applied to efficiently remove iodide. The physicochemical properties of the resultant materials were completely characterized and the results clearly implied that the morphology, Cu0 contents, pour structure and specific surface area could be tuned by regulating the Cu/Zn molar ration in ZIFs precursors. Adsorption experiments revealed that the as-fabricated nanocomposites displayed high adsorption capacity of 235.5 mg g-1 at pH = 3, as well as relatively fast dynamics and high selectivity. Interestingly, CuxZn1-x@NC exhibited an excellent reusability. The iodide adsorption amounts of regenerated materials was nearly 2 times superior to that of the initial one. Based on the characterization results of the regenerated adsorbent before and after adsorption, the iodide removal mechanism was proposed to be electrostatic adsorption of iodide in the material surface, followed by oxidation reaction of iodide to iodate by reactive oxygen species generated from zero-valent copper activated molecular oxygen reaction. The findings of this study offer a feasible strategy for the intensive treatment of radioactive iodine containing wastewater.
图解摘要：
原文链接：https://doi.org/10.1016/j.jece.2024.112235
撰稿：陈九玉博士 审核：朱宝忠