Electrokinetic Remediation of Cadmium and Copper from Clayey Soil Using Enhanced Conditioning Solutions

Abstract

Cadmium and copper contamination in clayey soils poses significant environmental and ecological risks due to the persistence, toxicity, and limited mobility of heavy metals in low-permeability soil matrices. Conventional remediation methods often exhibit reduced efficiency in fine-grained soils, necessitating the development of advanced in-situ treatment technologies. The present study investigates the electrokinetic remediation of cadmium and copper from clayey soil using enhanced conditioning solutions under controlled operational conditions. The research focuses on evaluating heavy metal migration, removal efficiency, electroosmotic flow behavior, and process optimization associated with electrokinetic treatment systems. Experimental analysis was conducted to examine the influence of electric potential gradient, treatment duration, conditioning solution composition, soil pH, moisture content, and electrode configuration on metal transport and remediation performance. Results demonstrate that electrokinetic remediation effectively mobilizes cadmium and copper ions through electromigration, electroosmosis, and electrophoretic mechanisms, resulting in substantial reductions in soil metal concentration. The study further reveals that enhanced conditioning solutions significantly improve metal solubility and transport efficiency by controlling pH gradients and preventing precipitation near electrode zones. Optimized operational conditions contributed to improved contaminant removal and enhanced uniformity of remediation throughout the clayey soil matrix. Comparative assessment with conventional soil remediation techniques confirms the advantages of electrokinetic treatment, including suitability for low-permeability soils, minimal excavation requirements, and reduced secondary environmental disturbance.