Degradation of polycyclic aromatic hydrocarbons in different synthetic solutions by Fenton’s oxidation

Abstract

The Fenton oxidation using phenanthrene (Phe), fluoranthene (Fle) and benzo[a]pyrene (BaP) as representative polycyclic aromatic hydrocarbon (PAH) contaminants was examined. The effect of the H₂O₂ concentration, the temperature and the competition between the PAHs in different solutions (methanol, surfactant and quartz) was investigated. The Fenton oxidation process was performed at pH = 2.5. The best conditions were recorded by adding 15 g H₂O₂ L^-¹ with a molar H₂O₂/Fe²⁺ ratio of 10/1 at T = 60°C. Phe, Fle and BaP were efficiently degraded in aqueous solution (Phe = 99%, Fle = 99% and BaP = 90%). The present study demonstrated that Phe, Fle and BaP were degraded to intermediate compounds and also oxidized to carbon dioxide. Among the by-products obtained, phthalic acids and benzoic acid were recorded as the major products.