Enhanced degradation of Rhodamine B dye by Fenton/peracetic acid and photo-Fenton/peracetic acid processes

Abstract

Abstract In this research, the efficiency of advanced oxidation processes (AOPs) including Fenton−Peracetic Acid (PAA) and photo-Fenton− PAA in the removal of the Rodamine B (RhB) dye from aqueous solutions were studied. Investigating the effect of operating parameters such as pH (3–9), contact time (2–30 min), PAA concentration (10–80 mg/L), FeCl3.7H2O concentration (10–100 mg/L), and dye concentration (25–500 mg/L) on the performance of AOPs in removal of RhB was considered. The results showed that by decreasing pH and dye concentration, RhB removal efficiency increased. The optimal conditions for removal of RhB using Fenton− PAA process were determined to be as follows: dye concentration = 50 mg/L, pH = 3, PAA concentration = 50 mg/L, contact time = 10 min, and FeCl3 = 50 mg/L; in these conditions, removal efficiency of the RhB was 99.9%. In contrast, the photo-Fenton− PAA process was able to remove this amount of dye in just 5 min. The high performance of the system in a short time is attributed to the synergistic effect of the photo-Fenton− PAA process in the presence of UV. Finally, RhB dye was completely degraded by the photo-Fenton− PAA process and converted into CO2 and H2O products. In general, the photo-Fenton− PAA process compared to other methods can be used as a suitable and reliable method for the treatment of effluents of the dyeing industry and discharge them to the environment.