A simple route for photocatalytic degradation of phenol in aqueous zinc oxide suspension using solar energy

In a laboratory study, the effectiveness of zinc oxide-mediated solar photocatalytic degradation of phenol was examined. The effect of various parameters like concentration of substrate, amount of photocatalyst, pH and irradiation time on the efficiency of photocatalytic degradation was studied. The demineralization of substrate was checked by Chemical Oxygen Demand (COD) reduction method. The photocatalytic degradation of phenol was found to be more effective under solar light in comparison to artificial visible light irradiation. It was observed that photodegradation of phenol is favorable in weakly acidic or neutral solutions. Zinc oxide can be reused for five times as it undergoes photocorrosion only to the negligible extent. This work envisages great potential that sunlight mediated photocatalysis has in the removal of phenol from waste water. 2008 Elsevier Ltd. All rights reserved