Environmental Research on Remediation of Cd-contaminated Soil by Electrokinetic Remediation

The basic idea proposed in this paper provides a novel and environmental friendly method to enhance the EK remediation of heavy metals contaminated soils. The remediation of Cd-contaminated soil is of great significance to the improvement of soil environment. As a new remediation technology, electrokinetic remediation has become a research hotspot in recent years. The test was carried out by self configuring Cd-contaminated soil to set up a hexagonal electrokinetic remediation device to study the effects of electric field strength, electrolyte types and bentonite addition on the removal rate of Cd in soils-contaminated by Cd, and further optimize the technical conditions of electrokinetic remediation. The results showed that the removal rate of total Cd was higher when the voltage intensity was 2v/cm, reaching 18.34%, so the electric field intensity was 2v/cm. Acetic acid was used as a circulating electrolyte to raise the current in the electrokinetic remediation process, which could effectively control the pH value of the cathode and reduce the concentration of Cd in the cathode. In the process of electrokinetic remediation, the addition of bentonite played a certain passivation role on all forms of Cd in soil. The highest removal rate of total Cd was 20.89%, and the energy consumption was reduced by 11.02%. Therefore, organic acids as electrolyte can not only effectively enhance the migration of Cd in soil, but also change the distribution of Cd in soil and improve the efficiency of remediation.