The oxidation study of N,N-diethyl-meta-toluamide in dual frequency ultrasonic reactor

Zeynep EREN, Kevin O'SHEA
2020 Environmental Research and Technology  
With the increasing concern of emerging contaminants (ECs), advanced oxidation processes (AOPs) have been widely investigated to fulfill the drinking water quality because of the potential adverse health effects of ECs. Accordingly, N,Ndiethyl-meta-toluamide (DEET) is selected as a model compound belonging ECs to monitor its ultrasonic oxidation which is one of the most popular AOPs in a dual frequency ultrasonic reactor (DFUR) using low-frequency probe (20 KHz) and high-frequency transducer
more » ... 0 KHz) type sources. DFUR was calorimetrically optimized in terms of power densities of both ultrasonic sources in order to provide the highest sonochemical yield with efficient energy output. Pseudo-first order kinetic equation was applied to results by measuring the concentration decreasing during the oxidation reactions. The pseudo-first-order rate constants, k, increased from 7.8x10 -3 min -1 (640 kHz, R 2 =0.930) to 13.5x10 -3 min -1 (DFUR, R 2 =0.990), by contrast, the rate constant was only 0.7x10 -3 min-1 (R 2 =0.281) for 20 kHz lowfrequency ultrasonic source. DEET oxidation was evaluated with the presence of different gas saturation (Ar, Air, O2, and N2); addition of hydrogen peroxide (PO), persulfate (PS) and monoperoxysulfate (MPS) and PO concentration effect
doi:10.35208/ert.749236 fatcat:qok42rpj2fgwfiptfdievaza4e