Sorption of palladium(II) on biotite, quartz and feldspar in brackish groundwater by batch experiment, sorption model and DFT calculation

在国际上，核废料管理组织（NWMO）等机构正在考虑在结晶岩层或沉积岩层中建立地下深层地质处置库，作为处置废核燃料的安全和长期解决方案。这些机构将不得不准备一份安全评估，以证明使用过的核燃料将在数十万年内得到安全管理。如果放射性核素在处置库的工程屏障和天然屏障中的吸附行为得到很好的表征，安全评估的可靠性将得到提高。 在加拿大，西北气象组织正在研究两个潜在的选址区域，一个是花岗岩，一个是沉积岩。本项目将研究Pd（II）在黑云母、石英和长石上的吸附。（Pd-107是一种长寿命的裂变产物，以可观的数量存在于使用过的核燃料中。石英和长石是花岗岩的主要矿物成分。黑云母是花岗岩的常见但次要的矿物成分，被认为是花岗岩对某些放射性核素（如Cs）的主要吸附。吸附反应将被确定通过整合实验与吸附模型和量子化学计算，和优化的平衡常数的反应将被评估。合格的吸附数据将编入西北气象组织的吸附数据库。这项研究将给加拿大社会带来长期利益，因为它将使人们更加相信已经选择了一个安全的地点（确保加拿大人未来的健康和福祉以及环境）。 该项目将利用麦克马斯特大学在痕量放射性核素方面的独特研究能力和专门知识，并扩大我们对安全评估中一种核素的吸附过程的科学理解。重要的是，这也将有助于培养废核燃料管理领域的高素质人员。

Internationally, agencies such as the NWMO (Nuclear Waste Management Organization) are considering underground deep geological repositories in either crystalline or sedimentary rock formations as a safe and long-term solution to the disposal of used nuclear fuel. These agencies will have to prepare a safety assessment to demonstrate that used nuclear fuel will be safely managed over hundreds of thousands of years. The reliability of the safety assessment will be improved if the sorption behaviours of radionuclides in the engineered and natural barriers of the repository are well characterized. In Canada, the NWMO is engaging with two potential siting areas, one in granitic rock and one in sedimentary rock. In this project, the sorption of Pd(II) on biotite, quartz and feldspar will be studied. (Pd-107 is a long-lived fission product present in used nuclear fuel in appreciable amounts. Quartz and feldspar are main mineral components of granite. Biotite is a common but minor mineral component of granite and is considered to dominate the sorption of some radionuclides such as Cs on granite.) The sorption reactions will be identified by integrating the experiments with a sorption model and with quantum chemistry calculations, and the optimized equilibrium constants of reactions will be evaluated. Qualified sorption data will be compiled in the sorption database of the NWMO. This study will lead to long-term benefits to Canadian society, as it will allow for increased confidence that a safe site has been selected (ensuring future health and wellbeing of Canadians and the environment). This project will use the unique research capability and expertise at McMaster University for working with trace radionuclides and extend our scientific understanding of sorption processes of one of the nuclides in safety assessment. Importantly, this will also contribute to the development of highly qualified personnel in the fields of used nuclear fuel management.