Removal of Food Dye Tartrazine (E102) from Aqueous Solution using ZnO and CuO-TiO2 as Photocatalysts

Abstract

Tartrazine dye has a major role in food as well as in other industrial products, like cosmetics, personal care products, pharmaceutical products and many more, therefore it is the cause of many environmental pollutions particularly water pollution. Its removal from water bodies is almost impossible with traditional techniques, because of heterogeneity in its composition. This investigation was carried out to examine the photo-catalytic degradation of food dye tartrazine (E102) from its aqueous solution, using ZnO (zinc oxide) and mixed CuO-TiO2 (copper oxide-titanium dioxide) as photo-catalysts at room temperature. The influence of several parameters, such as pH of medium, time of irradiation, concentration of dye solution and amount of catalyst was investigated. Kinetic analysis was also carried out using Langmuir – Hinshelwood approach. Maximum Photo-Catalytic Degradation (PCD) of E102 was observed to be at pH 1. Similarly significant rise in the degradation of E102 was observed with the time of irradiation, concentration of dye solution and amount of catalyst. From the results obtained it was observed that ZnO and CuO-TiO2 are effective photo-catalysts for the removal of E102 from its aqueous solution. However ZnO was observed to be more effective than CuO-TiO2 in the degradation of E102 from aqueous solution.