Polydopamine and poly(dimethylsiloxane) modified superhydrophobic fiberglass membranes for efficient water-in-oil emulsions separation.

Separation of oil/water mixture using superwetting materials has received great interest in recent years. However, it is challenging to efficiently separate water-in-oil emulsions due to their high stability and complex structures in the presence of surfactants. Here, we report preparation of polydopamine (PDA) and poly(dimethylsiloxane) (PDMS) modified superhydrophobic fiberglass (FG) membranes for efficient separation of water-in-oil emulsions. The membranes were fabricated by in turn deposition of PDA and chemical vapor deposition of PDMS. In order to study the structure-performance relationship, the membranes were characterized using field emission scanning electron microscope, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, etc. The membranes are superhydrophobic with a water contact angle of 152° and meanwhile superoleophilic with an oil contact angle of 0°. Also, the membranes demonstrate excellent acid, alkali and fire resistance. The absorption capacity of the membranes for diverse oils is 5.3-14.0 g g-1. Moreover, the membranes can remove more than 98% of water from the surfactant-stabilized water-in-oil emulsions. It is expected that the superhydrophobic FG membranes can be used for effective separation of diverse water-in-oil emulsions.