Tetracycline’s accumulation in the environment poses threats to human health and the ecological balance, necessitating efficient and rapid removal methods. Novel porous metal–organic framework (MOF) materials have garnered significant attention in academia due to their distinctive characteristics. This paper focuses on studying the adsorption and removal performance of amino-modified MIL-101(Fe) materials towards tetracycline, along with their adsorption mechanisms. The main research objectives and conclusions are as follows: (1) NH₂-MIL-101(Fe) MOF materials were successfully synthesized via the solvothermal method, confirmed through various characterization techniques including XRD, FT-IR, SEM, EDS, XPS, BET, and TGA. (2) NH₂-MIL-101(Fe) exhibited a 40% enhancement in tetracycline adsorption performance compared to MIL-101(Fe), primarily through chemical adsorption following pseudo-second-order kinetics. The adsorption process conformed well to Freundlich isotherm models, indicating multilayer and heterogeneous adsorption characteristics. Thermodynamic analysis revealed the adsorption process as a spontaneous endothermic reaction. (3) An increased adsorbent dosage and temperature correspondingly improved NH₂-MIL-101(Fe)’s adsorption efficiency, with optimal performance observed under neutral pH conditions. These findings provide new strategies for the effective removal of tetracycline from the environment, thus holding significant implications for environmental protection.

Advanced oxidation technology represented by hydroxyl radicals has great potential to remove residual antibiotics. In this study, we systematically compared the metronidazole (MTZ) degradation behavior and mechanism in the UV and UV/H₂O₂ systems at pH 3.00 condition. The results show that the initial reaction rates were 0.147 and 1.47 µM min⁻¹ in the UV and UV/H₂O₂ systems, respectively. The main reason for the slow direct photolysis of MTZ is the relatively low molar absorption coefficient (2645.44 M⁻¹ cm⁻¹) and quantum yield (5.9 × 10⁻³ mol Einstein⁻¹). Then, we measured $k_{\mathrm{MTZ},\mathrm{OH}_{ }^{•}}$ as 2.79 (±0.12) × 10⁹ M⁻¹ s⁻¹ by competitive kinetics, and calculated $k_{\mathrm{MTZ},\mathrm{OH}_{ }^{•}}$ and ${\left[\mathrm{OH}_{ }^{•}\right]}_{\mathrm{SS}}$ as 2.43 (±0.11) × 10⁹ M⁻¹ s⁻¹ and 2.36 × 10⁻¹³ M by establishing a kinetic model based on the steady-state hypothesis in our UV/H₂O₂ system. The contribution of direct photolysis and ^•OH to the MTZ degradation was 9.9% and 90.1%. ^•OH plays a major role in the MTZ degradation, and ^•OH was the main active material in the UV/H₂O₂ system. This result was also confirmed by MTZ degradation and radicals’ identification experiments. MTZ degradation increases with H₂O₂ dosage, but excessive H₂O₂ had the opposite effect. A complex matrix has influence on MTZ degradation. Organic matter could inhibit the degradation of MTZ, and the quenching of the radical was the main reason. ${\mathrm{NO}}_3^{-}$ promoted the MTZ degradation, while ${\mathrm{SO}}_4^{2-}$ and Cl⁻ had no effect. These results are of fundamental and practical importance in understanding the MTZ degradation, and to help select preferred processes for the optimal removal of antibiotics in natural water bodies, such as rivers, lakes, and groundwater