Solvent-free synthesis of defective Zr-based metal–organic framework from waste plastic bottles for highly efficient lomefloxacin removal

Large amount of polyethylene terephthalate (PET) plastics waster and emerging contaminants in water, including fluoroquinolone antibiotics, pose challenges to human survival. In this work, a green synthesis scheme is proposed in which the defective UiO-66 (d-UiO-66) is fabricated via a solvent-free routine by using PET plastics waster as raw materials for lomefloxacin (LOM) removal. In comparison with defect-free UiO-66, the created defect imparts d-UiO-66 with higher porosity and abundant defective Zr sites, which are beneficial to boost LOM adsorption. As expected, d-UiO-66 exhibited excellent LOM adsorption performances, showcasing a saturation adsorption capacity of 588 mg g−1 and a kinetic rate constant of 0.204 g mg−1 h−1, which are 3.5 and 2.0 times higher than those of the pristine UiO-66, respectively. Remarkably, the LOM saturation adsorption capacity of d-UiO-66 surpasses that of all reported adsorbents. Mechanism study reveals that this outstanding adsorption performance of d-UiO-66 is mainly ascribed to the abundant defective sites, high porosity, together with the strong hydrogen bonding interaction and π-π stacking interaction between d-UiO-66 and LOM. Therefore, the d-UiO-66 obtained by the solvent-free method can not only effectively upcycle PET plastic waster, but also efficiently remove LOM, demonstrating a potential routine to simultaneous address the solid PET waster and wastewater.