Data underlying the publication: Pushing the boundaries of electrochemical ion separation for near-identical ions

In recent decades, increasing global population and industrialization have driven interest in the sustainable extraction of valuable resources from water, as well as in water reuse applications. This includes selectively removing undesired ions, such as sodium, or extracting valuable ions, such as lithium, from water. These separations are difficult to achieve due to the high concentrations of competing ions with similar properties, such as charge and size. As a result, separating similar ions, e.g., sodium, potassium, and lithium, is often regarded as the ‘holy grail’ of ion separation. Although selective separation can be achieved with electrochemical desalination technologies, the limited selectivity for ions with the same charge is insufficient for many applications. In the publication, we introduce a novel approach for achieving exceptionally high selectivity between two very similar ions, sodium and potassium, by adapting switching times of ion collection. We demonstrate that our method, termed Concentration Dependent Switching (CDS), is effective for sodium and potassium, achieving high removal of one ion while leaving the other in solution. The high removal can be achieved to either of the ions in solution. We highlight its applicability to other challenging separations, including lithium and sodium. The CDS method can be integrated into any cyclically operated deionization technology that exhibits differences in the dynamics of adsorption and desorption of ions. This datafile contains the experimental data, the output of our models and the model files.

近数十年来，全球人口持续增长与工业化进程推进，推动了人们对从水体中可持续提取高价值资源以及水体回用相关应用的研究兴趣。此类应用涵盖从水体中选择性去除不期望的离子（如钠），或是提取具有高价值的离子（如锂）。由于存在大量性质（如电荷与粒径）相似的共存干扰离子，此类分离过程往往难以实现。因此，分离钠、钾、锂这类性质相近的离子，常被视作离子分离领域的“圣杯”。尽管借助电化学脱盐技术可实现选择性分离，但对于同电荷离子的选择性有限，难以满足诸多应用场景的需求。本研究中，我们提出一种全新方法，通过调整离子收集的切换时长，实现钠与钾这类性质极为相近的离子之间极高的选择性分离。我们将该方法命名为浓度依赖切换法（Concentration Dependent Switching, CDS），实验证明其对钠、钾离子分离效果优异，可实现对其中一种离子的高去除率，同时保留另一种离子于溶液中，且可针对溶液中的任意一种离子实现高去除率。我们还验证了该方法在其他高难度分离场景中的适用性，例如锂与钠离子的分离。浓度依赖切换法可集成至任何具备离子吸附与解吸动力学差异的循环式脱盐技术中。本数据集文件包含实验数据、模型输出结果以及模型文件。