Repairing compound-contaminated soil using EK-laccase combination repairing technology

Abstract

Complex soil pollution is a major part of soil pollution, and heavy metals and organic pollutants coexist in the soil in most cases. With the common pollutants phenol and heavy metals (Cu and Cd) as the target pollutants, this study investigated the principles and mechanism of electro-kinetic (EK)-laccase combination technology for repairing contaminated soils by developing an EK repair device. Additionally, the migration of heavy metals and migration and the degradation of phenol in complex environments were analyzed. The results showed that the removal efficiency of phenol in soil with Cd2+ in the cathode region was 27.6% lower than that with Cu2+ in the cathode region, while the removal efficiency of phenol in the anode region exceeded 90% in both cases. The removal efficiency of Cd2+ and Cu2+ in the soil were 56.7% and 61.2% respectively. Contaminants such as succinic acid and p-benzoquinone and catechol in the repaired soil were detected by GC/Ms. In this repairing system, the degradation of phenol could be either electrocatalytic oxidation or laccase catalytic oxidation.