Kinetic of oxidation and mineralization of priority and emerging pollutants by activated persulfate

In this work, abatement of diuron (D), (selected as an example of priority pollutant) and nicotine (N), caffeine (C), ibuprofen (I) and phenacetin (P), (chosen as examples of target emerging pollutants), have been carried out by using persulfate activated by Fe2+. Reactions were accomplished at room temperature in a batch or semicontinuous (SC) manner, using 5 mg/L of each pollutant.The effectiveness of the process was measured by attending at the pollutant conversion and TOC removal. Kinetic model for both reaction rates – pollutants oxidation and mineralization – was developed – on the basis of a radicalic mechanism and kinetic parameters calculated. Moreover, the kinetic model discriminated was successfully validated by comparison of predicted and experimental values obtained for pollutant and TOC conversion when mixtures of pollutants were treated at different persulfate and iron concentrations. Iron addition process presented a remarkable effect on oxidation results. It was found that a continuous slow release of Fe2+ notably increased the efficiency of the process.

► Oxidation of prioritary and emerging pollutants with persulphate was studied.
► A radical mechanism for pollutants oxidation and mineralization was proposed.
► A kinetic model for a mixture of pollutants was developed and validated.
► Kinetic parameters were calculated by fitting experimental data.
► Iron addition policy was taken into account in the model (batch or semicontinuous).