Remediation of Nickel -Contaminated Clayey Soil by Electro-Kinetic Technology Coupled with zeolite –a Permeable Reactive Barrier

Abstract

This study examines the effectiveness of utilizing different purging solution acetic acid (AA), ammonium citrate (AC), ethylenediarninetertraacetic acid (EDTA), and sodium dodecyl sulphate (SDS)_ as purging solutions for saturating soil, as well as a catholyte solution in the electro-kinetic (EK) process coupled with zeolite as a permeable reactive barrier (PRB), which was loaded nickel-contaminated clayey soil in three regions: near the anode side, in the center, and near the cathode side. Twelve different tests (Series-1& Series-2) were conducted on clay soil spiked with nickel in concentrations of 250 mg/kg. These tests were conducted with voltage gradient of 1.5V/cm and processing time of 4 days for the Series-1 and 3 days for the Series-2. Results indicated that the EK/PRB leads to a significant improvement in the efficiency of removal as well as reducing the remediation duration, where it was noted that the removal efficiency in tests when zeolite-PRB was inserted at various regions (near the anode side, at the center, and near the cathode side) was 51.6%, 59.12%, and 41.76%, respectively, its greater than the test of the electro-kinetic process without a barrier was equal to 34.4% under the same conditions. Furthermore, the experiments have shown that inserting a barrier in regions near the anode side, at the center, and near the cathode side did not greatly affect the pH variation.

DOI: http://dx.doi.org/10.5755/j01.erem.73.4.19188