Superhydrophobic-superoleophilic heptafluorodecyl triethoxysilane/graphitic carbon spheres Co-modified porous monolith for water/oil separation

Water/oil separation has been a flourishing research focus due to severe oil-spill accidents. The current work reports on preparation, characterization and water/oil separation performance of heptafluorodecyl triethoxysilane (FAS) and graphitic carbon spheres (GCS) co-modified mullite porous ceramic (FAS/GCS-MC) with superhydrophobic and superoleophilic characters. The water contact angle of FAS/GCS-MC was determined as about 161 degrees. The continuous water/oil separation rates for paraffin, vegetable and vacuum pump oils were 3.4 x 10(4) g m(-2) min(-1), 2.2 x 10(4) g m(-2) min(-1) and 1.3 x 10(4) g m(-2) min(-1), respectively; even after 10 cycles, the separation rates remained almost unchanged in high selectivity (above 95%). The as-prepared FAS/GCS-MC was resistant to the temperature change and acid/base erosion, and showed stable superhydrophobicity and separation efficiency. In addition, the separation rate after applied a voltage to FAS/GCS-MC could be obviously enhanced by a self-heating process.

Automated summary

The study successfully achieved water/oil separation with superhydrophobic and superoleophilic properties using modified ceramics with heptafluorodecyl triethoxysilane and graphitic carbon spheres. The material showed stable separation rates at high selectivity even after 10 cycles, resistant to temperature change and acid/base erosion, and could be enhanced significantly through a self-heating process.