Significant process has been made over recent years in capacitive deionization (CDI) to develop novel system configurations, predictive theoretical models, and high-performance electrode materials. To bring CDI to large scale practical applications, it is important to quantitatively understand the intrinsic tradeoff between kinetic and energetic efficiencies, or the relationship between energy consumption and the mass transfer rate. In this study, we employed both experimental and modeling approaches to systematically investigate the tradeoff between kinetic and energetic efficiencies in membrane CDI (MCDI). Specifically, we assessed the relationship between the average salt adsorption rate and specific energy consumptions from MCDI experiments with different applied current densities but a constant effluent salinity. We investigated the impacts of feed salinity, diluted water salinity, diluted water volume per charging cycle, and electrode materials on the kinetics-energetics tradeoff. This tradeoff can be employed to optimize the design and operation of CDI systems and compare the performance of different electrode materials and CDI systems.

近年来，在电容去离子（CDI）方面已经进行了重要的研究，以开发新颖的系统配置，可预测的理论模型和高性能电极材料。为了将CDI应用于大规模的实际应用，重要的是定量地了解动力学效率与能​​量效率之间的内在折衷，或者能耗与传质速率之间的关系。在这项研究中，我们采用实验和建模方法来系统地研究膜CDI（MCDI）的动力学效率和能量效率之间的折衷。具体来说，我们评估了在不同施加电流密度但废水含盐量恒定的情况下，MCDI实验得出的平均盐吸附速率与比能耗之间的关系。我们研究了进料盐度，稀释水盐度，每个充电周期的稀释水量以及电极材料对动力学-能量学折衷的影响。这种权衡可用于优化CDI系统的设计和操作，并比较不同电极材料和CDI系统的性能。