Highly efficient and flexible electrospun carbon silica nanofibrous membrane for ultrafast gravity-driven oil water separation
Tai, Ming Hang
Tan, Benny Yong Liang
Sun, Darren Delai
Leckie, James O.
Date of Issue2014
School of Civil and Environmental Engineering
A novel free-standing and flexible electrospun carbon–silica composite nanofibrous membrane is newly introduced. The characterization results suggest that the electrospun composite nanofibers are constructed by carbon chains interpenetrated through a linear network of 3-dimensional SiO2. Thermogravimetric analysis indicates that the presence of insulating silica further improve the thermal resistance of the membrane. Additionally, the mechanical strength test shows that the membrane’s toughness and flexibility can be enhanced if the concentration of SiO2 is maintained below 2.7 wt %. Thermal and chemical stability test show that the membrane’s wettability properties can be sustained at an elevated temperature up to 300 °C and no discernible change in wettability was observed under highly acidic and basic conditions. After surface-coating with silicone oil for 30 mins, the composite membrane exhibits ultra-hydrophobic and superoleophilic properties with water and oil contact angles being 144.2 ± 1.2° and 0°, respectively. The enhanced flexibility and selective wetting property enables the membrane to serve as an effective substrate for separating free oil from water. Lab-scale oil–water separation test indicates that the membrane possesses excellent oil–water separation efficiency. In addition, its inherent property of high porosity allows oil–water separation to be performed in a gravity-driven process with high-flux. We anticipate that this study will open up a new avenue for fabrication of free-standing carbonaceous composite membrane with tunable flexibility for energy efficient and high-throughput production of clean water.
DRNTU::Engineering::Environmental engineering::Water treatment
ACS applied materials & interfaces
© 2014 American Chemical Society. This is the author created version of a work that has been peer reviewed and accepted for publication by ACS Applied Materials & Interfaces. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at:[http://dx.doi.org/10.1021/am501758c]