Enhanced Tetracycline Removal via Synergistic Adsorption and Photocatalysis on MIL-۵۳(Fe)-(COOH)@Fe₂O₃

This study presents a novel MIL-۵۳(Fe)-(COOH)@Fe₂O₃ composite designed to effectively remove tetracycline (TC) from water, addressing limitations of traditional wastewater treatments. Combining the high surface area of metal-organic frameworks (MOFs) with photocatalytic α-Fe₂O₃, the composite provides a dual approach of adsorption and photocatalysis for enhanced TC degradation. Synthesized via a hydrothermal method, its structure was confirmed using FT-IR, SEM, XRD, and BET analyses. Using a Design of Experiments (DOE) approach, key parameters such as MOF amount, TC concentration, pH, and reaction time were optimized, revealing significant impacts on removal efficiency. Under optimal conditions, the composite achieved an ۸۰.۲۷% removal rate, with kinetic studies indicating a pseudo-second-order model best described the process. The composite demonstrated stability over three recycling cycles and effectively removed ۸۵% of TC in real wastewater samples under sunlight. The photocatalytic mechanism primarily involved reactive oxygen species (•OH and •O₂⁻), which facilitated degradation. While promising, further improvements are needed for long-term stability. Overall, this composite shows potential as a sustainable solution for mitigating pharmaceutical pollutants in water resources.

Keywords:

Tetracycline , MIL-۵۳(Fe)-(COOH)@α-Fe₂O₃ , Photocatalytic degradation , Adsorption , Wastewater Treatment , Design of Experiments (DOE)