Iron-Based Amorphous Alloy Enhanced Electrokinetic Method for Remediation of Copper-Contaminated Soil

Iron-based amorphous alloy (Fe78Si9B13AP) permeability reaction barrier (PRB)-enhanced electrokinetic method (Fe78Si9B13AP-EK) was used to remediate simulated copper-contaminated soil and actual contaminated soil. The results showed that increasing soil moisture content and voltage gradient during remediation could promote the migration of Cu2+ to the cathode. Under the experimental conditions of 40% soil moisture content and 3 V/cm voltage gradient, the removal rate of copper in simulated copper-contaminated soil by Fe78Si9B13AP-EK is higher than that by zero valent iron-enhanced electrokinetic method (ZVI-EK), which could reach 80.32%. The reason is that, the higher reducibility of Fe78Si9B13AP can quickly immobilize Cu2+ that migrates to PRB, which avoids the accumulation of Cu2+ in the cathode. Under the same conditions, the removal rate of copper in actual copper-contaminated soil by Fe78Si9B13AP-EK is 42.37%. The chemical form of residual copper in soil is mainly biounavailable stable state, which effectively reduces the environmental risk of soil.