Degradation of Amido Black Dye Using Ultra-Violet Light Catalyzed by Iron Oxide Nanoparticles: Kinetics and Mechanism of Degradation

In this study, we investigated the degradation of amido black dye in an aqueous solution using ultra-violet (UV) light catalyzed by iron oxide nanoparticles (nano-Fe). The nano-Fe was synthesized by sodium borohydride reduction of ferric chloride solution and was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray fluorescence spectrophotometry (XRF). The SEM of the nano-Fe showed regular spherical particles, the XRD examination showed a weak and broad peak at Fe (1 1 0), and the XRF study showed that the element with the highest composition was Fe2O3 (60.80%). The degradation experiments showed that the UV light catalyzed by nano-Fe could effectively degrade amido black dye. The nano-Fe/UV system could degrade 5 mg/L of amido black dye up to 93.2% at 254 nm after being irradiated for 60 min. The nano-Fe/UV system could be described by the Langmuir–Hinshelwood kinetic model, and the rate constants (kapp) were 0.0183–0.0323 min−1. Thus, UV light combined with nano-Fe can be applied for the efficient remediation of dye wastewater.