Here we detail a previously unappreciated loss mechanism inherent to capacitive deionization (CDI) cycling operation that has a substantial role determining performance. This mechanism reflects the fact that desalinated water inside a cell is partially lost to re-salination if desorption is carried out immediately after adsorption. We describe such effects by a parameter called the flow efficiency, and show that this efficiency is distinct from, and yet multiplicative with, other highly-studied adsorption efficiencies. Flow losses can be minimized by flowing more feed solution through the cell during desalination; however, this also results in less effluent concentration reduction. While the rationale outlined here is applicable to all CDI cell architectures that rely on cycling, we validate our model with a flow-through electrode CDI device operated in constant-current mode. We find excellent agreement between flow efficiency model predictions and experimental results, thus giving researchers simple equations by which they can estimate this distinct loss process for their operation.

在这里，我们详细介绍了电容去离子（CDI）循环操作固有的先前未曾意识到的损耗机制，该机制对确定性能具有重要作用。该机理反映出以下事实：如果在吸附后立即进行解吸，则细胞内的淡化水会部分损失而无法重新盐化。我们通过称为流动效率的参数来描述这种影响，并表明该效率与其他经过高度研究的吸附效率截然不同，但又相乘。通过在脱盐过程中使更多的进料溶液流过电解池，可以使流动损失最小化。但是，这也导致废水浓度降低较少。尽管此处概述的基本原理适用于所有依赖循环的CDI单元架构，我们使用在恒定电流模式下运行的流通式电极CDI设备验证了我们的模型。我们发现流动效率模型的预测结果与实验结果之间有着极好的一致性，从而为研究人员提供了简单的方程式，使他们可以估算其运行过程中的独特损失过程。