Effectiveness of Zinc Oxide/Iron Oxide Nanocomposites in Treatment of Colored Wastewater

Abstract Background & Aims: Industrial wastewater containing persistent dyes is a serious environmental concern, threatening aquatic ecosystems and public health. Although numerous treatment technologies have been developed for the treatment of colored wastewater, many remain ineffective in degrading complex dye molecules. Usage of ZnO/Fe۲O۳ nanocomposites presents a promising approach by enhancement of ultraviolet (UV) absorption and photocatalytic efficiency. This study aimed to evaluate the efficiency of zinc oxide/iron oxide (ZnO/Fe۲O۳) nanocomposites in the removal of methyl orange dye from wastewater with the goal of enhancement of ZnO’s photocatalytic properties through modification with Fe۲O۳. Materials and Methods: In this experimental study, the ZnO/Fe۲O۳ nanocomposite was synthesized using a chemical co-precipitation method. A cylindrical UV reactor with a ۱-liter outer volume and an internal UV lamp was used to evaluate photocatalytic efficiency. Effects of photocatalyst dosage, initial dye concentration, pH, and contact time on dye removal were investigated, with experiments conducted using a ۵۰۰ mL working volume and ۳۰ samples. The experiments were carried out at room temperature, and the initial pH was adjusted by using H۲SO۴. Descriptive analysis of the data and regression were conducted in Microsoft Excel software. Results: Under optimal conditions with a pH of ۹, ۰.۲۵ mg/L nanocomposite dose, ۲ mg/L dye concentration, and ۹۰-minute contact time, the removal efficiency of methyl orange dye reached ۸۹%. In comparison, UV treatment alone removed only ۶% of the dye, and ZnO/Fe۲O۳ without UV achieved ۵۶% removal. Conclusion: The ZnO/Fe۲O۳ nanocomposites significantly enhance photocatalytic efficiency, owing to the synergistic effect of ZnO and Fe۲O۳ and improved UV absorption. These findings highlight the potential of ZnO/Fe۲O۳ nanocomposites as a cost-effective and eco-friendly solution for industrial wastewater treatment.

کلیدواژه ها:

Coloring agents ، Isolation and purification ، Methyl orange ، photocatalyst ، Wastewater ، ZnO/Fe۲O۳