An in silico study of sustainable drug pollutants removal using carboxylic acid functionalized-MOF nanostructures (MIL-53 (Al)-(COOH)2): Towards a greener future

Emerging environmental pollutants have become a major environmental challenge due to the highly toxic effluents produced by industries. Among these emerging pollutants, pharmaceutical drugs, which are consumed and are highly soluble, lead to the severe degradation of water resources. To address this issue, adsorptive capturing methods have been considered as a potential solution due to their efficiency and environmental compatibility. This study focuses on the use of carboxylic acid functionalized MIL-53 (Al) (CA/MIL-53 (Al)) for the removal of pharmaceutical pollutants (PhPs) such as acetaminophen, ibuprofen, aspirin and methyl salicylate. The study was conducted employing quantum mechanical (QM), Monte Carlo (MC) and molecular dynamics (MD) simulations. The results of QM analysis exhibited that the functionalization of MIL-53 (Al) with carboxylic acid (CA) groups improved its adsorption affinity. Moreover, the MOF-water-Ibuprofen mixed configurations showed higher chemical reactivity and adsorption capacity. It was demonstrated that the MIL-53 (Al) adsorption characteristics were significantly improved following its functionalization with CA groups. This study highlights the potential of functionalized MOFs as a promising solution for PhPs removal from water resources. The results of this study provide valuable information for further research and the development of new adsorbents for the removal of emerging pollutants in the environment.