Titanium dioxide mediated photocatalytic degradation of malathion in aqueous phase

Abstract

The photocatalytic degradation of technical grade pesticide ‘malathion’ has been studied in aqueous suspensions of TiO₂. The main aim of using this process is to degrade the toxic complex structure of the pesticide to harmless products by treating the sample in the UV-reactor. The COD measurements are carried out in order to study the percentage mineralization and degradation is studied under different parameters like varying <i style="mso-bidi-font-style:normal">p</i>H, catalyst concentration, and oxidant addition (H₂O₂). The degradation of the pesticide is found to be maximum at optimum catalyst loading of 3.0 g/L, <i style="mso-bidi-font-style:normal">p</i>H of 6.0 and oxidant concentration of 2.5 mL/200 mL. Adsorption is negligible as compared to photocatalytic degradation of the pesticide.