Résumé
Sonocatalytic defunctionalization of 5 mM EDTA is studied for the first time in the presence ofair passivated Ti and Ti@TiO NPs using power ultrasound (345 kHz, absorbed P = 0.25 W mL ) at 22-51 Cunder Ar, Ar/20%O and air. Ti@TiO core-shell NPs have been obtained using sonohydrothermal treatment(SHT) of air-passivated Ti NPs in pure water. The thickness of TiO shell is dependent on the temperatureused throughout the SHT treatment (Table 1) . Nevertheless, complete defunctionalization of 5 mM EDTA isachieved in the presence of Ti NPs under Ar/20%O atmosphere and the presence of TiO tends to reducethe activity of Ti NPs towards EDTA degradation. Following the kinetics of H O production and EDTAdefunctionalization quantitatively under different conditions, we identified the mechanism of EDTAdefunctionalization in the presence of passivated Ti NPs. There are two reaction pathways of EDTAdegradation, the first occurs at the vicinity of the cavitation bubble under the action of OH /HO and the secondtakes place on the surface of Ti by O molecules primary activated throughout the cavitation process (Fig. 1)