Capacitive deionization (CDI) is surprisingly efficient to remove the aqueous Cs ion due to its small hydrated size and low hydration energy. But current experimental techniques fail in investigating deeply into the influence of some key electrode characteristics due to the difficulty in experimentally fabricating the electrodes as desired. This work presents a dynamic transport model of salt ions in a flow-by CDI cell. By using this model, the electrode thickness, macro- and micro-porosity are investigated to evaluate Cs ion removal efficiency and energy efficiency particularly from the aspect of ion transfer by the approach of decomposing energy contribution. The results indicate that the thick electrode coupled with the high current could greatly improve the effluent quality, but reduce the salt adsorption capacity (SAC). The increasement of the current density from 3 A/m² to 6 A/m² greatly decreases the SAC from 4.0 mg/g to 0.8 mg/g. Lower current could prolong the charging period, leading to more ions stored in the micropore. Not all the electrical energy is consumed for separating ions from the feed as desired, but some are used for driving ions diffusing in the electrodes. Consequently charging efficiency will be reduced especially when the electrodes are characterized with high porosity. It is highlighted that future work is required to further consider the complex details of porous structure and pore connectivity.

由于其水合尺寸小和水合能低，电容去离子 (CDI) 对于去除水性 Cs 离子出人意料地有效。但由于难以按要求通过实验制造电极，目前的实验技术无法深入研究某些关键电极特性的影响。这项工作提出了盐离子在流过 CDI 池中的动态传输模型。通过使用该模型，研究了电极厚度、大孔隙率和微孔隙率，以评估 Cs 离子去除效率和能量效率，特别是通过分解能量贡献的方法从离子转移方面。结果表明，厚电极与大电流相结合可以大大改善出水水质，但会降低盐吸附能力 (SAC)。²至 6 A/m ²将 SAC 从 4.0 mg/g 大大降低至 0.8 mg/g。较低的电流可以延长充电时间，导致更多的离子存储在微孔中。并非所有的电能都用于按需要从进料中分离离子，但有些电能用于驱动离子在电极中扩散。因此，充电效率将降低，尤其是当电极具有高孔隙率的特征时。需要强调的是，未来的工作需要进一步考虑多孔结构和孔隙连通性的复杂细节。