Superhydrophobic and superoleophilic “sponge-like” aerogels for oil/water separation

• DOI: 10.1007/s10853-015-9034-9
• Publication Date: 2015-04-22T13:34:58Z
• Authors: Yuxi Yu; Xiaoyun Wu; Jiyu Fang
• Keywords: EFFICIENCY; Multidisciplinary; WASTE-WATER; OIL REMOVAL; Materials Science; PHYSICAL-PROPERTIES; 02 engineering and technology; SILICA AEROGELS; METHYLTRIMETHOXYSILANE; 0210 nano-technology; 6. Clean water

We report a facile approach to synthesize superhydrophobic and superoleophilic “sponge-like” aerogels through sol–gel reaction followed by supercritical drying, in which MTES and DMDES are used as co-precursors, EtOH as a solvent, CTAB as a surfactant, and HCl and NH3·H2O as catalysts. The MTES–DMDES-based aerogels formed at the optimal molar ratio of MTES: DMDES: EtOH: H2O: HCl: NH3·H2O: CTAB at 1.1: 0.9: 6: 12: 2 × 10−3: 2 × 10−3: 0.14 with a low density of 0.0897 g/cm3 show a compression ratio of 80 % under 36.85 kPa stress. They are superhydrophobic and superoleophilic with a water contact angle of 153.6° and an oil contact angle of 0°. We find that the MTES–DMDES-based aerogels show the high adsorption capacity for various kinds of organic liquids and the excellent recyclability in removing oil from water.