Degradation of organophosphorus pesticide diazinon using activated persulfate: Optimization of operational parameters and comparative study by Taguchi's method

Abstract

The degradation of organophosphorus insecticide diazinon as the major concern of the present study was scrutinized. Advanced oxidation processes (AOPs) as a dominant route to degradation was considered. Also, to create the robust hydroxyl radicals for decontamination, sodium persulfate was used. Activation of persulfate was utilized both thermally and by UV light. UV-LEDs were applied instead of conventional UV lamps. Besides, use of periodic-based irradiation showed that more energy-saving itinerary could be provided utilizing UV-LEDs. In ruin procedures, the effect of individual and collaborative factors such as temperature, time, UV light intensity, oxidant and diazinon concentration was investigated. Furthermore, to optimize influential parameters, the Taguchi method was practiced. As a result, temperature has been shown to be the most effectual factor by 82.99% contribution. It was also found that the sum of the diazinon was efficiently reduced by the UV/thermal/S2O82- process. The most important mechanistic aspect of diazinon removal was also found to be a substitution reaction of sulfur by oxygen to form diazoxon through oxidation.