MIL-۱۰۰(Cr)@Fe_۲O_۳ Composite: A Novel Material for Methylene Blue Removal via Adsorption and Photocatalysis

This research presents the development of an innovative MIL-۱۰۰(Cr)@Fe₂O₃ composite, designed to effectively eliminate Methylene Blue (MB) from wastewater through a combined mechanism of adsorption and photocatalysis. The material leverages the large specific surface area and strong adsorption properties of amine-functionalized MIL-۱۰۰(Cr), a Metal-Organic Framework (MOF), in conjunction with the photocatalytic functionality of Fe₂O₃ nanoparticles. Structural and morphological characterization was carried out using FT-IR, SEM, BET, and UV-Vis techniques, verifying the composite's successful synthesis and surface engineering. BET results confirmed the presence of mesopores ranging from ۲ to ۵۰ nm, which are ideal for adsorption and catalytic reactions. A factorial Design of Experiments (DoE) methodology was employed to systematically investigate the influence of crucial operational parameters—MOF dose (۰.۰۲–۰.۰۶ g/L), initial MB concentration (۳۰–۵۰ mg/L), contact time (۳۰–۹۰ min), and pH level (۶–۱۰)—on removal efficiency. Under optimized conditions of ۰.۰۶ g/L MOF, ۳۰ mg/L MB, pH ۱۰, and ۹۰ minutes of reaction, complete dye removal (۱۰۰%) was achieved. Kinetic modeling revealed that the adsorption behavior followed a pseudo-second-order kinetic model (R² = ۰.۹۴۶۷, k₂ = ۰.۰۸۵ min⁻¹), suggesting a chemisorption-driven process with an adsorption capacity of ۵۱.۲ mg/g. The composite maintained high performance in real wastewater samples, with removal efficiency exceeding ۸۵%, and demonstrated acceptable reusability over six successive cycles, although some decline in activity occurred afterward. These findings underscore the material's potential as a robust, efficient, and sustainable candidate for practical dye removal applications in wastewater treatment systems, optimized through statistical design.

کلیدواژه ها:

MIL-۱۰۰(Cr)@Fe۲O۳ ، Methylene blue ، Photocatalytic degradation ، Adsorption ، Wastewater treatment ، Design of Experiments (DoE)[