Facile fabrication of covalent organic framework functionalized superhydrophobic porous sponges for highly efficient water/oil separation

Considering the serious environmental pollution and economic losses caused by increasing oil spills and chemical leaks, effective and eco-friendly methods of oil/water separation should be urgently developed. Herein, a facile strategy (about 20 min) was developed for integrating covalent organic framework (COF) particles with melamine sponges (MS) by covalent bonding, and then a superhydrophobic COF/MS composite (denoted OA-CP@MS) could be further obtained by following modification with a 1-octadecylamine/water dispersion. Specifically, the synthesis process was developed under a mild condition that avoid the need for sealing and high-temperature treatments. It was proven that the fabricated OA-CP@MS presented a prominent absorption capacity for various organic reagents, in which adsorption capacity of chloroform could be up to 173 g/g. Owing to its excellent chemical robustness in strong alkaline and saline environments and in various organic solvents, the prepared OA-CP@MS showed a great potential to perform oil/water separation in complex practical conditions. Its rapid preparation process, fluorine-free treatment, and water-based modification would extend the application of COF materials in oil/water separation.