mil-100(cr)@fe2o3 composite: a novel material for methylene blue removal via adsorption and photocatalysis

This research presents the development of an innovative mil-100(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-100(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 2 to 50 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 (0.02–0.06 g/l), initial mb concentration (30–50 mg/l), contact time (30–90 min), and ph level (6–10)—on removal efficiency. under optimized conditions of 0.06 g/l mof, 30 mg/l mb, ph 10, and 90 minutes of reaction, complete dye removal (100%) was achieved. kinetic modeling revealed that the adsorption behavior followed a pseudo-second-order kinetic model (r² = 0.9467, k₂ = 0.085 min⁻¹), suggesting a chemisorption-driven process with an adsorption capacity of 51.2 mg/g. the composite maintained high performance in real wastewater samples, with removal efficiency exceeding 85%, 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.