Heterogeneous photocatalytic degradation of rose bengal: Effect of operational parameters

The photocatalytic degradation of rose bengal dye has been investigated using ZnO nanoparticles as photocatalyst. ZnO nanoparticles were found to be efficient catalyst for the degradation of dye and 98% degradation was observed in 90 min. Effect of various operational parameters such as amount of catalyst (0.25-2.00 g/L), concentration of dye (0.01-0.05 mM) and pH (3-11) of dye solution on the rate of dye degradation was studied. The most favorable results for the degradation of rose bengal were observed at pH 5 at a catalyst loading of 1 g/L. Moreover, hydroxyl radicals have been detected in the photocatalytic reaction mixture by using terephthalic acid photoluminescence probing technique. The reusability of the catalyst has also been studied and catalyst was found to be active even after being used for 5 times.