Degradation of High Level m-Cresol by Zinc Oxide as Photocatalyst

In this study, the high concentration of m-cresol as a sample of organic pollutants was degraded in the presence of zinc oxide and UV irradiation during 6h at laboratory scales. The amount of photocatalyst, pH and m-cresol concentration were considered as effective factors on the photodegradation. The demineralization of m-cresol was measured by UV-Vis spectrophotometry while the total organic carbon-analyzer was used to determine the mineralization. The ultrahigh performance LC was used to identify probable intermediates. The results showed optimum condition at pH 7-9, which is the natural pH of industrial wastewater. Moreover, 100% of m-cresol was removed after 5h of irradiation time, which is quite significant. The detected intermediates were 3,5-hydroxytoluene, 2,5-hydroxy-benzaldehyde, and 3-hydroxy-benzaldehyde after 3h of reaction time. Reusability of the photocatalyst showed insignificant reduction in the photo-catalytic performance. In conclusion, this investigation indicated high potential of zinc oxide suspension to remove high level concentration of m-cresol under UV irradiation.