Magnetic, self-heating and superhydrophobic sponge decorated with BN and CoFe2O4 for high-efficient cleanup of crude oil spills using facile co-precipitation strategy

Accidents involving petrochemical spills have repeatedly threatened the security of the eco-environment. The leaked crude oil exhibits poor fluidity, low adsorption efficiency, and urgent issues such as potential fire risks that require immediate attention. Herein, a multifunctional superhydrophobic sponge Si@CFO@BN@PU was prepared by a simple co-precipitation strategy based on BN and CoFe2O4. The results demonstrate that Si@CFO@BN@PU exhibits excellent superhydrophobic properties, with a water contact angle of 162 degrees and a slide angle of less than 10 degrees, and oil adsorption capacity ranging from 32.3 to 68.4 g/g. Furthermore, the modified sponge also possesses certain magnetic properties, allowing Si@CFO@BN@PU to be moved on the water surface via an external magnetic field and effectively adsorb floating oil. Meanwhile, the modified sponge exhibits excellent photothermal properties. The whole sponge can be heated up to 80 degrees C in just 60 s under simulated sunlight conditions, effectively reducing the adsorption time of viscous oil by 90 %. Moreover, the cone calorimeter test results demonstrate excellent fire safety of Si@CFO@BN@PU even after adsorption of petroleum. The peak heat release rate (pHRR), total heat release (TSR), maximum CO release rate, and maximum CO2 release rate have decreased by 37.8 %, 23.3 %, 45.4%, and 34.1 %, respectively. Therefore, Si@CFO@BN@PU is an effective, safe and sustainable new adsorbent material with a wide range of applications in treating petrochemical spills.