Research Information System
Water, Air, and Soil Pollution, vol.236, no.7, 2025 (SCI-Expanded)
The electrokinetic remediation (EKR) technique was employed for cadmium (Cd)-contaminated soil to study the cross-effect of voltage gradient and electrolyte concentration on removal efficiency. Response Surface Methodology over Central Composite Design (CCD) was used to design the experiments. In addition, the effect of electrode material on EKR was investigated using two different electrodes, graphite, and stainless steel. The distribution and migration behavior of Cd in soil was explored through chemical speciation and sequential extraction procedure. The findings revealed that the voltage gradient and EDTA concentration were positively correlated with the removal efficiency at the optimized conditions of 2.5 V/cm and 0.15 M EDTA to achieve 27.8% removal in 10 h. The voltage gradient had a more profound effect on the removal efficiency as compared to EDTA concentration. The EKR treatment effectively reduced the bioavailability of Cd by removing water-soluble and exchangeable fractions and rendering the transformation of Cd to reducible and residual fractions. The Human Health Risk Assessment study was performed which revealed that EKR was successful in reducing the non-carcinogenic adverse effects by 29% and total carcinogenic risks from one in a thousand to one in a hundred thousand in adults, while children still exposed to high potential non-carcinogenic effects. The economic evaluation of all experiments concluded that the stainless steel electrode was more suited for Cd removal as compared to the graphite electrode with better removal (30%) and low specific cost (5.8 US$/g Cd). The study shows that EKR is successful in reducing the overall toxicity of Cd in soil and humans at a relatively low cost and less treatment time.