Aluminium-based MOF CAU-1 facilitates effective removal of florfenicol via hydrogen bonding

Abstract

The widespread use and subsequent accumulation of florfenicol (FFC), a common antibiotic, through the food chain poses significant risks to aquatic ecosystems and human health, necessitating effective strategies for its removal from water bodies. To solve the challenge, herein, we developed a novel aluminum-based metal–organic framework CAU-1, engineered for the efficient adsorption of FFC. CAU-1 contains the plentiful –NH₂ and μ-OH groups with the positively charged on the surface. In the adsorption process, CAU-1 perform hydrogen bonding interactions with FFC’s functional groups (−F, –OH, −Cl, –NH–, and −SO₂–). Furthermore, the positively charged surface of CAU-1 enhances FFC adsorption via electrostatic attraction together. FFC adsorption equilibrium on CAU-1 is attained within 180 min with a monolayer adsorption capacity of 386 mg/g at 303 K, surpassing most of the reported adsorbents. The exothermic FFC adsorption process on CAU-1 remains largely unaffected by coexisting ions. Additionally, CAU-1 can be efficiently regenerated using a mixed solution of 0.1 M HCl and ethanol–water as an eluent. This work highlights CAU-1’s potential as an effective adsorbent for FFC removal, emphasizing the importance of tuning or designing surface functional groups on adsorbents to boost their adsorption capabilities.