Hydrophobic Fluorous Metal-Organic Framework Nanoadsorbent for Removal of Hazardous Wastes from Water

The spill of oil in the ocean and the abuse of pharmaceutical and personal care products in water systems would pose a direct threat to the environment and human health. Metal-organic frameworks (MOFs) can serve as promising adsorbents to solve these problems, but most MOFs are unstable in water, thereby limiting their applications. To address these issues, we proposed a simple postsynthesis modification strategy with perfluoroalkyl acid to produce hydrophobic MOF nanoadsorbents. The modified nanomaterial retained its original structure and porosity, while its water contact angle increased to 145 degrees. The hydrophobic nanomaterial showed an obvious increase in the adsorption capacity for a diversity of organic solvents and gave an outstanding recycling performance. It also exhibited good oil-water separation capabilities. In addition, we investigated the efficiency of UiO-66-F in the adsorption of carbamazepine from its aqueous solutions, and it was found that the framework's ability to remove carbamazepine in water increased remarkably. Furthermore, the adsorption isotherms and kinetics analyses of the adsorption were conducted, and the results fitted with the Langmuir isotherm model and the pseudo-second-order kinetic model, respectively. Therefore, the hydrophobic perfluoroalkyl MOF nanomaterial UiO-66-F can be deemed as a promising matrix to capture hazardous wastes from water.

Automated summary

The study proposed a strategy of post-synthesis modification using hydrophobic perfluoroalkyl acid to produce MOF nanoadsorbents with enhanced adsorption capacity for organic solvents, as demonstrated by UiO-66-F. The modified nanomaterial also showed good oil-water separation capabilities and efficiency in removing pollutants such as carbamazepine from water.