In this study, we present a novel soil electrochemical remediation technology (called S-FCDI), which is based on flow-electrode capacitive deionization (FCDI), for Cd removal from kaolin while under continuous operation mode. The results demonstrated that Cd can be effectively removed from kaolin with reasonable energy consumption and minimal macroelement loss. The carboxylic (–OOH) functional groups on the surface of activated carbon (AC) facilitated the transfer of Cd from kaolin onto carbon surface. A stable acidic environment, which is advantageous for continuous Cd desorption, was achieved as a result of the balance between H⁺ generation and transmembrane migration. Once these net negative charges on the particle were eliminated or reversed, the adsorbed Cd could be released easily and driven in concentrated stream by electrostatic repulsion. Under the optimal operating conditions (i.e., carbon =50 g/L, j = 3.47 A/m², pH_i = 3.2, [NaCl]_a =8.6 mmol/L), more than 80% Cd was removed from (200 g) kaolin after continuous 19 h operation at a relatively low electricity consumption of 22.7 kW h/kg Cd and a limited Al loss of 0.06 wt‰. These results from this work demonstrated that S-FCDI could be an alternative in-situ soil remediation technology for heavy metal removal with low soil damage.

在这项研究中，我们提出了一种新颖的土壤电化学修复技术（称为S-FCDI），该技术基于流电极电容去离子（FCDI）技术，用于在连续运行模式下从高岭土中去除Cd。结果表明，可以以合理的能耗和最小的宏观元素损失有效地从高岭土中去除Cd。活性炭（AC）表面上的羧基（–OOH）官能团促进了Cd从高岭土转移到碳表面上。由于H ⁺之间的平衡，因此获得了一个稳定的酸性环境，有利于Cd的连续解吸。生成和跨膜迁移。一旦消除或逆转了颗粒上的这些净负电荷，就可以轻松释放吸附的Cd，并通过静电排斥作用将其驱动成浓流。在最佳操作条件下（即碳= 50 g / L，j  = 3.47 A / m ²，pH _i  = 3.2，[NaCl] _a = 8.6 mmol / L），从（200 g ）在相对较低的22.7 kW h / kg Cd的电耗和0.06 wt‰的有限Al损失下连续运行19 h后的高岭土。这项工作的这些结果表明，S-FCDI可以作为一种替代性的原位土壤修复技术，用于去除土壤中的重金属而对土壤的损害较小。