Introduction of Resin Barrier to Improve the Efficiency of Electrokinetic Remediation for Pb-Contaminated Soil

Developing an effective strategy to solve the "focus effect" of the traditional electrokinetic remediation (EKR) method during treatment of Pb-contaminated soil is challenging, but meaningful.Here, a novel permeable reactive barrier was constructed by coupling H + modified D001 resins (H-type D001) with the electrokinetic remediation (EKR) method to achieve this goal.Owing to the existence of ion exchange between Pb 2+ and H + , after introduction of H-type D001 resin into the EKR systems, the "focusing effect" was significantly weakened.To be specific, Pb 2+ ions were effectively adsorbed by the resin barrier (RB) before migrating to the precipitation zone, and the adsorption of Pb 2+ ions enabled H + ions to be desorbed from the H-type D001 resins, thus improving the pH environment required for EKR.As a result, Pb 2+ removal efficiency of the traditional EKR method was improved.Compared with the EKR method, the removal efficiency of Pb in soil by the RB-EKR method improved by 37.8%, relatively.Analysis on mass distribution proportion of Pb removed indicated that the majority (53.01%) of Pb was removed by RB adsorption process.This work provides a simple but effective method for modifying the traditional electrokinetic remediation system to improve remediation ability towards treating heavy metal-polluted soil.