Photocatalytic degradation of imazethapyr, an imidazolinone family herbicide, was investigated in titanium dioxide aqueous suspension in the presence of electron acceptors such as potassium persulfate and sodium periodate, as well as in the presence of two inorganic salts such as sodium sulfate and sodium dihydrogen phosphate at 30ºC. A pseudo-first order kinetic model was used to discuss the results. The imazethapyr disappearance as a function of the radiation time was analyzed by high performance liquid chromatography. In comparison between two oxidants, the degradation was faster in the presence of periodate, meanwhile in the presence of the inorganic salt sodium sulfate retarded the oxidation more than dihydrogen phosphate ions in the TiO2 suspension.
photocatalysis; imazethapyr; titanium dioxide; oxidant; inorganic ion
