Department of Chemical Engineering, AC Tech, Anna University, Chennai, 600025, Tamil Nadu, India.
Centre For Energy Storage Technologies, Anna University, Chennai, 600025, Tamil Nadu, India.
Environ Sci Pollut Res Int. 2024 Apr;31(19):28764-28774. doi: 10.1007/s11356-024-32979-7. Epub 2024 Apr 1.
Flow electrode capacitive deionization (FCDI) is a promising technology for efficiently treating industrial brine with high salt content. However, its desalination performance is currently limited by internal resistance. Achieving an effective FCDI system relies on active electrode materials with high conductivity. This study compares the desalination performances of the widely used flow electrode activated carbon (AC) with more conductive materials, reduced graphene oxide (rGO), and ZnO/rGO composite. Additionally, the lack of particle-to-particle contact in the flow electrode contributes to internal resistance and to address this, a cationic surface-active agent is introduced. This agent forms a stable dispersion, creating a space for enhanced mass loading of the active material. This modification enhances the conductive network and particle contact, reducing the diffusion path and promoting rapid ion transport. With a 5 wt% loading, ZnO/rGO achieved a 73% salt removal efficiency, surpassing AC at 63%. Furthermore, the surfactant-modified ZnO/rGO flow electrode with a 7 wt% loading demonstrated an 81% salt removal efficiency.
流电极电容去离子（FCDI）是一种很有前途的技术，可高效处理高盐含量的工业盐水。然而，其脱盐性能目前受到内阻的限制。实现有效的 FCDI 系统依赖于具有高导电性的活性电极材料。本研究比较了广泛使用的流电极活性炭（AC）与更具导电性的材料，还原氧化石墨烯（rGO）和 ZnO/rGO 复合材料的脱盐性能。此外，流电极中颗粒间缺乏接触会导致内阻，为了解决这个问题，引入了一种阳离子表面活性剂。该试剂形成了稳定的分散体，为活性材料的增强质量负载创造了空间。这种改性增强了导电网络和颗粒接触，减少了扩散路径并促进了快速离子传输。在 5wt%负载下，ZnO/rGO 的盐去除效率达到 73%，超过了 AC 的 63%。此外，表面活性剂改性的 ZnO/rGO 流电极在 7wt%负载下的盐去除效率达到 81%。
