Photocatalytic degradation of leather dye over ZnO catalyst supported on alumina and glass surfaces

The photocatalytic degradation of leather dye, Acid green 16, has been inve stigated over a ZnO catalyst supported on two different materials, namely a lumina and glass beads (3-5 mm diameter), Sunlight was used as the energy s ource. The alumina-supported ZnO outperformed the glass-supported ZnO under identical operational conditions suggesting that the dye molecules are ads orbed on the alumina supports to make a high concentration environment arou nd the loaded ZnO, The degradation efficiency was greater at pH = 4 compare d to other acidic and neutral pH. Also, the degradation efficiency was a li ttle bit higher in alkaline medium, which correlates with the adsorption be haviour of acid green 16 on the alumina supported ZnO. The influence of ino rganic oxidants like H2O2, FeCl3 and Fenton reagent on the degradation effi ciency were systematically studied. The decolourisation and extent of degra dation of the dye were determined by UV-VIS spectroscopy and COD reflux met hods, respectively. Complete mineralisation of the dye was conformed by Hig h performance liquid chromatography (HPLC) analysis.