Experimental Actinide Nano-chemistry for the Future of the Civil UK Plutonium Inventory

在英国，使用核电发电是能源安全和实现净零的关键。经过塞拉菲尔德有限公司(SL)60年的商业核燃料再加工，英国拥有世界上最大的民用钚(Pu)库存。SL代表核退役管理局(NDA)对英国民用钚库存的当前和未来管理是核退役带来的最重要挑战之一。挑战的难度和规模反映在资金的提供上：20亿GB用于后处理厂，40亿GB用于储存到2120年，100亿GB用于未来的钚管理。Pu的库存形式为氧化铟(An=铀U，或Pu)或混合氧化镝粉末(MOX)，储存在Sellafield现场的气密包装中。位于中央实验室的国家核实验室(NNL)委托SL进行的研究表明，在鳗系氧化物的化学方面存在着重大的知识差距。这些数据目前无法解释，也无法显示AnO2的属性在存储过程中发生了变化。这导致了人们对安全以及未来如何处理这些材料的担忧。此外，迫切需要建立计划于2027年开始的钚库存再处理和重新包装的最佳操作条件，并确保从2027年起的库存储存安全可靠。这一知识差距源于工业条件下钚化学的复杂性和实验研究的困难。我的观点是，不仅需要新的实验性鳗系元素材料，而且还需要研究它们的新方法。这是通过我最近借调到SL，并与关键利益攸关方(SL、NNL、NDA)密切合作而制定和了解的。FLF将能够合成一类在核退役中具有广泛应用潜力的新类型的榄系元素纳米材料。这项研究将提供关键的实验数据，在原子水平上的鳗系元素的结构和成键，这在以前只能从理论上进行研究。催化技术将被用于探测和量化鳗系纳米材料与有问题的工业污染物的反应性。这也是首次将知识和技术应用于工业催化，以应对核工业的技术挑战。这项工作是与SL和NNL合作进行的，旨在产生可直接与正在进行的工业工作相比较的数据。先进的表征和反应性研究将得到新光谱工具开发的支持。同步加速器和中子科学将被利用，最终将与振动光谱学相结合，并用于操纵台实验。这些研究将是世界上第一次。FLF科学的影响将通过与英国(SL、NNL、NDA)的工业利益攸关方合作实现，并通过英美联合项目(洛斯阿拉莫斯国家实验室)和欧盟委员会联合研究中心(Karlsruhe)在国际上实现。科学知识的转化以满足最终用户在核退役方面的实际需要是粮食安全论坛的一个主要目标。这将通过为科学证据基础做出贡献来实现，从而为安全案例、工程设计以及最终英国政府未来关于Pu管理的决策提供信息。

In the UK, electricity generation using Nuclear Power is key to energy security and to achieving Net Zero. After six decades of commercial nuclear fuel reprocessing by Sellafield Ltd (SL), the UK has the largest inventory of civil plutonium (Pu) worldwide. The current and future management of the UK's civil Pu inventory by SL on behalf of the Nuclear Decommissioning Authority (NDA) is one of the most important challenges presented by nuclear decommissioning. The difficulty and scale of the challenges are reflected in the provision of funding: £2 billion for the retreatment plant, £4 billion for storage until 2120, and £10 billion for future Pu management. The Pu inventory is in the form of actinide oxide AnO2 (An = uranium U, or Pu) or mixed-actinide oxide powders (MOX) and stored in gas-tight packages on the Sellafield site. Research commissioned by SL, undertaken by the National Nuclear Laboratory (NNL) at Central Lab, has revealed that there is a significant knowledge gap in the chemistry of actinide oxides. The data cannot currently be explained and show that the properties of the AnO2 have changed during storage. This has led to concerns about safety, and how to handle these materials going forward. Moreover, there is an urgent need to establish optimal operating conditions for Pu inventory retreatment and repackaging, which is scheduled to begin in 2027, and to ensure safe and secure inventory storage from 2027 onwards.This knowledge gap results from the complexity of Pu chemistry under industrial conditions, and the difficulty of experimental studies. My insight is that not only are new experimental actinide materials needed, but so are new ways of studying them. This has been developed and informed through my recent secondment at SL, and working closely with key stakeholders (SL, NNL, NDA). The FLF will enable the synthesis of a new class of actinide nanomaterials, with broad application potential in nuclear decommissioning. This Fellowship will provide crucial experimental data on actinide structure and bonding on an atomic level, which has previously only been possible to study theoretically. Catalysis technology will be used to probe and quantify reactivity of actinide nanomaterials with problem industrial contaminants. This is also the first application of knowledge and technologies used in industrial catalysis to address nuclear industry technical challenges. This work is in partnership with SL and NNL and has been designed to generate data directly comparable to ongoing industrial work. Advanced characterisation and reactivity studies will be supported by the development of new spectroscopic tools. Synchrotron and neutron science will be utilised, ultimately in combination with vibrational spectroscopies, and in operando experiments. These studies will be a world-first. The impact of the FLF science will be realised through working in partnership with industrial stakeholders both in the UK (SL, NNL, NDA) and internationally through joint UK/US programmes (Los Alamos National Laboratory) and the European Commission Joint Research Centre (Karlsruhe). The translation of scientific knowledge to meet real end-user needs in nuclear decommissioning is a major goal of the FLF. This will be achieved by contributing to the scientific evidence base, therefore informing safety cases, engineering designs, and ultimately future UK government decision-making on Pu management.