Polyethylene glycol/citric acid cross-linked framework based on aminated cyclodextrin with enhanced water stability for tetracycline hydrochloride removal

Tetracycline hydrochloride (TCH), a widely used antibiotic, poses serious environmental risks due to its persistence in aquatic ecosystems and potential to induce antibiotic resistance. Metal-organic frameworks (MOFs) represent a promising class of materials for antibiotic removal. This study reports the development of a novel polyethylene glycol and citric acid cross-linked amino-β-cyclodextrin-metal-organic framework (PCC-NH 2 -βCD-MOF). This design leverages NH 2 -β-CD as a key functional ligand while enhancing the material’s hydrophilicity and structural stability. Structural and morphological characterization via FT-IR, XRD, and SEM confirmed the successful synthesis, while BET and zeta potential analyses revealed a porous structure with a negatively charged surface. Under optimized conditions, the adsorbent achieved a high TCH adsorption capacity of 278.2 mg/g. The adsorption process conformed to the Langmuir isotherm model, it had a higher theoretical maximum capacity of 526.3 mg/g at 25 °C, and the kinetics showed a temperature-dependent shift, transitioning from pseudo-second-order behavior at lower temperatures to pseudo-first-order at elevated temperatures. Thermodynamic analysis confirmed a spontaneous and exothermic process (ΔG 0 < 0, ΔH 0 = −34.85 kJ/mol). The adsorbent demonstrated excellent practical potential, retaining 78 % of its initial capacity after four generation cycles and achieving an 82 % TCH removal rate in simulated wastewater, underscoring its remarkable selectivity and reusability. The adsorption mechanism was identified as a synergistic combination of cavity inclusion within the β-CD, hydrogen bonding with surface functional groups, and electrostatic interactions. With advantages including a green synthesis process, cost-effectiveness, easy regeneration, and multi-mechanism adsorption capability, PCC-NH 2 -βCD-MOF exhibits significant promise for application in TCH-contaminated wastewater treatment.