Synthesis of UiO-66/cotton fiber composite via coupling method for enhanced quinolone adsorption

In this study, UiO-66/Cotton composite adsorbents with varied UiO-66 loadings were fabricated via a coupling strategy and applied for the adsorption of quinolone antibiotics (QNs)—including norfloxacin (NOR), ciprofloxacin (CIP), pefloxacin (PEF), and moxifloxacin (MFX)—from aqueous media. Under optimal conditions ( T = 298 K, pH=8.0, dosage=1 g/L, contact time=2 h, C 0 =100 mg/L), the maximum adsorption capacities followed the order: PEF (106.29 mg/g) > MFX (85.30 mg/g) > NOR (83.64 mg/g) > CIP (75.53 mg/g). Adsorption was enhanced by increased UiO-66 loading, though utilization efficiency decreased. Optimal performance was observed under pH 6.0–10.0 and in the presence of divalent cations. The process followed pseudo-second-order and Freundlich models, involving coordination, hydrogen bonding, electrostatic attraction, and π–π interactions. The UiO-66/Cotton composite (18.63 % loading) exhibited excellent reusability, maintaining 81.25 % removal efficiency for PEF after five cycles. Moreover, its solid–liquid separation and washing efficiency improved by approximately 40.1-fold and 44.3-fold, respectively, compared to pristine UiO-66. This work highlights the potential of MOF-based composite materials for effective QNs removal in water treatment applications.