Degradation of Atrazine by Advanced Oxidation Processes

Advanced oxidation processes like ozonation (O3) and ultrasonic irradiation (US) can be employed for the removal of recalcitrant compounds from water matrices. Atrazine is a pesticide which has been banned in the EU countries, since it is toxic and potentially carcinogenic even in very small concentrations. After their use in agricultural areas, the pesticides tend to leave residuals on the soil and in the surface waters or the groundwaters. The degradation of atrazine was studied by scientists before, but they could not get very high removal rates with the conventional wastewater treatment techniques. This study includes the investigation of the efficiency of O3 and US and also of their combined application (US + O3) for the degradation and potential mineralization of atrazine in water. Under the conditions applied, all three systems proved to be effective in inducing atrazine oxidation, leading to 95% removal for O3 and 78% for US after 90 min of treatment. The synergy observed in the combined schemes, mainly due to the effects of US in enhancing the O3 decomposition, led to higher removal (100%) for 20 min treatment. The synergy was so efficient that the results showed significantly higher removal level for shorter treatment duration.