The influence of polychromatic light on methomyl degradation in TiO2 and ZnO aqueous suspension

Abstract

The photocatalytic degradation of the insecticide methomyl in water using TiO2 Merck Eusolex (R) T (anatase) under Osram ultra-vitalux (R) lamp light (315-400 nm, 300W) was studied. The effect of the operational parameters, such as initial concentration of catalyst, initial methomyl concentration, initial salt concentration (NaCl), and pH, was studied. The optimal concentration of catalyst was found to be 2.0 g/L. Using the Langmuir-Hinshelwood mechanism as a base, a pseudo-first-order kinetic model was illustrated and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (K-MT = 0.079 L/mg and k