Title: Photocatalytic degradation of methomyl in the presence of titanium dioxide (Degussa P-25) Author(s): Tamimi M (Tamimi, Malika), Belmouden M (Belmouden, Mustapha), Qourzal S (Qourzal, Samir), Assabbane A (Assabbane, Ali), Ait-Ichou Y (Ait-Ichou, Yahia) Source: FRESENIUS ENVIRONMENTAL BULLETIN 15 (10): 1226-1231 2006
Summary: The photocatalytic degradation of methomyl in aque-ous solution by UV-irradiation with titanium dioxide (揇e-gussa P-25? has been studied, and its degradation rate measured by high performance liquid chromatography (HPLC). It was dependent on the concentration of metho-myl, and the nature of TiO2 surface. The presence of TiO2 accelerated the degradation of methomyl, in comparison with direct photolysis, and resulted in a complete miner-alization. The kinetics of methomyl photo-degradation fol-low the model of Langumir-Hinshelwood (L-H), as observed for many pollutants. The influence of certain inorganic ion species was also studied. The presence of NO3- ions did not appreciably affect the photodegradation rate of metho-myl, whereas that of Cl-, SO42- and HCO3- ions signifi-cantly affect photo-mineralization of the pollutant. Photo-catalysis proved to be an excellent new advanced oxida-tion technology (AOT) to eliminate methomyl present in surface and ground waters.