Experimental study of the remediation of atrazine contaminated soils through soil extraction and subsequent peroxidation

This paper presents a feasibility study in the field of the remediation of soils contaminated with atrazine. Experimental tests were performed on an artificially contaminated synthetic soil. Atrazine was removed from the soil by flushing with an aqueous solution at 5 vol.% of ethanol. Experimental tests of evaporation and Fenton’s oxidation on the extracted solution were then performed in order to transform atrazine into its oxidation products. Tests were performed in the presence of a peroxide excess the ratio between Fe2+ and H2O2 was 1:10. Peroxide was first added in order to reduce the consumption of hydroxyl radicals by their reaction with the excess of Fe2+. The degradation mechanism of atrazine during oxidation with Fenton’s reagent in the presence of ethanol was investigated. Results showed that due to the non selective nature of Fenton’s reagent a high consumption of reagent was needed to achieve a significant atrazine oxidation from solutions at 4.5 vol.% of ethanol. While at a Fe2+ concentration of 3mMatrazine practically disappeared from pure aqueous solutions within 2 h, a degradation yield of only 28.1% was observed in the presence of ethanol even when Fe2+ concentration was 15 mM.