Ultrasonic coupling with electrical current to effective activation of Persulfate for 2, 4 Dichlorophenoxyacetic acid herbicide degradation: modeling, synergistic effect, and a by-product study

AbstractIn this research work, we investigated the ability of the oxidative degradation of 2, 4-Dichlorophenoxy acetic acid herbicide via ultrasonic-assisted in electro-activation of the persulfate system in the presence of nano-zero valent iron. The effect of experimental parameters such as pH value [4 –8], electrical current (0.5–1 A), persulfate concentration (0.25–0.5 mg.l−1), nano zero-valent iron dose (0.05 –0.1 mg.l−1), and initial organic pollutant concentration (50 –100 mg.l−1) on the ultrasonic-electropersulfate process performance was assessed via central composite design. The combination of ultrasonic waves with the electrochemical process to activation of persulfate showed better efficiency into 2, 4-Dichlorophenoxy acetic acid herbicide degradation compared to their implementation in individual and binary systems. Following optimal conditions (pH  = 5.62, 0.80 A applied electrical current, 0.39 mg/L persulfate concentration, 0.07 mg/L nano-zero valent iron, and 50 mg/L 2,4-Dichlorophenoxy acetic acid concentration in 40 min reaction), nearly 91% removal was done. Moreover, the complete removal of 2, 4-Dichlorophenoxy acetic acid, 92% COD, and 88% TOC removal was achieved by this process near 140 min reaction. The scavenging experiment confirmed the role of free oxidizing species in the degradation of 2, 4-Dichlorophenoxy acetic acid during the process. Approximately 50% improved 2, 4-Dichlorophenoxy acetic acid removal in the process ...
Source: Journal of Environmental Health Science and Engineering - Category: Environmental Health Source Type: research