Metal-organic framework composites for nuclear waste clean-up

长寿的环境移动式放射性核素，如~(99m)Tc，对地下水污染构成重大问题，并对塞拉菲尔德等核设施的清理工作提出严峻挑战。可以使用配置为可渗透反应屏障(PRB)材料的固相吸附剂来解决这一问题，该材料对主要的99TcO4-阴离子具有高选择性，将其从受污染的地下水中捕获。在南安普敦化学和南安普敦国家海洋学中心(NOCS)最近建立的一个多学科项目中，我们正在调查被称为金属-有机骨架的微孔材料作为PRB去除氚的潜力。MOF是一种高比表面积的多孔固体，基于金属离子和有机连接物的连接，构成了一个模块化的材料平台，确保它们具有高度可调的结构和功能，以优化特定应用的性能。在本项目中，您将准备和表征一系列新的和现有的MOF，并直接评估它们的锶吸收性能，预计将研究一些氚吸收机制。为了增加其作为可再生能源的实际效用，将把性能最好的MOF配置为膜和柱等复合材料，受污染的地下水可以流经这些材料。成功的候选人将在化学和NOCS方面花费时间，并将在与核工业相关的材料合成、表征和分析方法方面发展广泛的技能。

Long-lived environmentally-mobile radionuclides such as 99Tc (technetium) pose a significant groundwater contamination issue and present a serious challenge for the clean-up of nuclear sites such as Sellafield. This can be addressed using solid-phase adsorbents configured as permeable reactive barrier (PRB) materials that have high selectivity for the dominant 99TcO4- anion, trapping this from contaminated groundwaters. In a recently established multi-disciplinary project between Southampton chemistry and the National Oceanography Centre Southampton (NOCS) we are investigating the potential of microporous materials known as metal-organic frameworks (MOFs) as PRBs for technetium removal. MOFs are high surface area porous solids based on the linking of metal-ions and organic linkers and constitute a modular materials platform ensuring they have highly tuneable structures and functionality for the optimisation of their properties for given applications. In this project you will prepare and characterise a range of new and existing MOFs and directly evaluate their technetium uptake properties, and it is expected that a number of technetium uptake mechanisms will be investigated. In order to increase their practical utility as PRBs the best performing MOFs will be configured as composite materials such as membranes and columns through which contaminated groundwater can flow. The successful candidate will spend time in both chemistry and NOCS and will develop broad skills in materials synthesis and characterisation and analytical methods relevant to the nuclear industry.