Catalytic oxidation of dye wastewater by metal oxide catalyst and granular activated carbon

Bench experiments were conducted to investigate the catalytic oxidation of dye wastewater by metal oxides. The catalytic oxidation was carried out in an air fluidized-bed reactor and was assisted by V2O5 as catalyst, granular activated carbon (GAC), and hydrogen peroxide. The experimental results indicated that, in the present oxidation process, both chemical and physical actions took place which are distinctly different from the decomposition of dyes involved in previous research. This may account for the high efficiency of the GAC catalytic oxidation method in color and chemical oxygen demand (COD) reductions of dye wastewater. An adsorption/oxidation/desorption hypothesis was proposed to account for the catalytic oxidation. Test runs were performed to determine the optimal operating conditions and amounts of metal oxide catalyst, GAC, acid H2O2. (C) 1999 Elsevier Science Ltd.