Flexible silica aerogel prepared using multi‑silicon source system for oil-water separation

This paper reports a novel flexible silica aerogel prepared under ambient pressure using a multi-silica source precursor system. Compared with the single-silica-source system, the new aerogel exhibits excellent flexibility and can be bent up to 180° and compressed to 75 % of its original size without destroying its structure. It shows high adsorption capacity for a wide range of organic solvents, in particular for methylene chloride with an adsorption capacity of 13.7 g/g. In addition, the water contact angle of this aerogel was as high as 141°. The specimens were thoroughly characterised and tested to explore their physicochemical properties. The pore structure was analysed in detail using mercuric pressure and gas adsorption methods, revealing the mechanism behind the high adsorption of organic solvents. These excellent properties make this aerogel have significant potential for application in oil-water separation. Both gravity-assisted filtration and peristaltic pump-assisted filtration can be used for oil-water separation.