生物炭电极材料及其在电容去离子中的应用进展:制备、性能、再生和挑战

Development of biochar electrode materials for capacitive deionization:preparation,performance,regeneration and other challenges

电容去离子技术(CDI)是一种潜在的经济高效的海水淡化技术,其电吸附能力取决于电极材料的结构和性能。生物质材料因具有资源丰富、成本低和结构独特等优点,成为CDI电极材料领域的研究热点。然而对生物炭电极的制备、脱盐性能、及再生现状仍然有待总结和阐明。本文梳理并对比了近几年来国内外生物炭电极的制备及其在电容去离子中的应用,重点阐述了生物炭材料、CDI运行参数等对脱盐性能的影响,发现生物炭电极的脱盐量与材料的介孔占比成正相关。进一步阐明了离子的选择性吸附主要依赖于离子半径、电荷等离子特性以及工作电压、充电时间和进水水质等实验参数。最后,对该类材料电极再生的现状进行探讨并对未来发展作出了展望。

Capacitive deionization(CDI)is a potential cost-efficient desalination technology.Its performance is intrinsically limited by the structure and properties of the electrode materials.Biomass materials have become a research hotspot for CDI electrode materials because of their abundance,low cost,and unique structure.The preparation,desalination performance,and regeneration status of biochar electrodes are summarized and clarified.Their preparation and use in CDI in recent years are presented and compared,and the effects of biochar electrode materials and CDI operating parameters on the desalination performance are emphasized.It is found that the salt adsorption capacity is positively correlated with the percent mesoporous material they contain.The selective adsorption of ions mainly depends on ion properties like ionic radius and charge as well as voltage,charging time and feed water characteristics.The current status and methods of electrode regeneration are discussed and future developments are suggested.