Removal of Chromium Contaminated Soils by Electro-Kinetic Method

Abstract

Chromium-contaminated soil is a serious environmental problem that threatens human health and the environment. Electrokinetic technology is used as a promising solution to treat these soils, as it relies on applying an electric field to remove pollutants from the soil. In this study, four experiments were conducted, where experiments have shown that the use of wheat straw as an available, cheap, economical and efficient adsorbent material to prevent the occurrence of reverse osmosis. The results showed that the percentage of removal increased with the increase in the acidity of the medium, that is, as the pH decreased. This is due to an increase in the movement of pollutants as the soil particles become more positively charged, which enhances Attract negative heavy metal ions. This leads to increased movement of heavy metal ions into soil pores, making them more susceptible to transport under the influence of an electric field. The results proved that when using a disinfection solution with a pH of 2, it gave a higher result compared to pH 7 and 12, where the percentage of removal was 78.3%, 62.6 %, and 51.9% respectively. The dissolution of these metals can be enhanced by adding oxalic acid at a constant voltage gradient 1.2 v/cm and an initial concentration of 200 mg/kg. It was noted after the end of the experiment that the percentage of removal reached 81.9%, as the concentration of metals on the cathode side was higher than on the cathode side. The anode, and this is due to the migration of metals under the influence of electromigration to the cathode side, where the chromium concentration was 47 mg/kg at the cathode side, 27 mg/kg at the anode side.

Keywords

• chromium
• heavy metals
• soil
• wheat straw
• oxalic acid
• electro-kinetic