Impact of Photo-remediation on Anthracene PAHs in treated wastewater using ZnO/TiO2/H2O2 Catalysis

Abstract

The remediation of carcinogenic Polycyclic Aromatic Hydrocarbons )PAHs( such as Anthracene (3 Rings) in different sources of wastewater was examined using a mix of Zink Oxide, Titanium Oxide, and Hydrogen peroxide (ZnO/ TiO2/H2O2). Eleven wastewater sources were collected from different industrial wastewater and treated wastewater (5 Farms, Main treatment plant, Tanning factory treated wastewater, Tanning factory non-treated wastewater, Carton factories, Factories Lake, and Grease refining plants. Anthracene was extracted by QuEChERS methodology and Analyzed by GCMSMS/TQD. Remediation techniques were applied by using different UV wavelengths irradiation on photolysis of PAHs under two wavelengths (254 and 306 nm) UV irradiation with ZnO + TiO2+ H2O2catalysts for 10 h. Also, the influence of remediation time and several parameters on Anthracene photolysis have been studied. The results indicate that Tanning factory non-treated wastewater had the highest concentration of Anthracene PAHs. The average recovery of Anthracene ranged from 92-96% and Detection Limit (DL) was 5 µg/l. The results of Anthracene concentration in tested wastewater ranged from 21.09 -223.69 µg/l. Also, the results show the anthracene was not detected after 5, 8, and 10h after the remediation using UV 254nm ZnO + TiO2+ H2O2. On the other side, the Anthracene was not detected after 3, 5, and 8h after the remediation using UV 254nm/ZnO + TiO2+ H2O2. Generally, the results of Photoremediation were effective and sufficient for the Anthracen. The impact of photocatalytic illumination of ZnO + TiO2 + H2O2yields valence band holes and conduction band electrons, which interact with the surface adsorbed molecular oxygen to give superoxide radical anions, and finally, the water produces radicals of HO•. These radicals oxidize the target molecule (Anthracene) to Anthraquinone.