Enhancement oxidation of the 2,4-dinitrophenol using electro-activated persulfate: Effect of degradation process parameters

Abstract

2,4-Dinitrophenol (DNP) is the carcinogenic, persistent, and a priority pollutant with bioaccumulation property that threatens human health and the environment. The present study was aimed to investigate the efficiency of electrochemically activated persulfate for DNP degradation in batch and continuous mode. Experiments were performed in an electrolytic batch plexiglass reactor equipped with anode and ring-shaped cathode electrode. The effect of operational parameters includes pH, electrode potential, PS concentration; DNP concentration, electrode type, and flow rate were evaluated on DNP removal. The results showed that pH and electrode potential had a significant influence on the degradation efficiency. The optimum condition was obtained in acidic condition (pH 3), electrode potential of 10 V, DNP concentration of 10 mg/L, Na2S2O8 of 15 mM and hydraulic retention time (HRT) of 80 min by Fe-SM electrode (91.6%). Comparisons between different electrodes indicated the degradation rate was increased based on the following order: Fe-SM > Pt-SM > Fe-SS > Pt -SS. Results suggested that Fe-based electrodes are the effective alternative for PS activation in order to DNP removal.