Design and fabrication of PPTA-braid-reinforced PFA/GE hollow fiber composite membranes

Due to the effects of the rapid development of modern society and fresh water resource pollution, water shortage has further accelerated, which is becoming a very urgent problem. Herein, the poly (p-phenylene terephthalamide)-(PPTA-) braid-reinforced (PBR) poly(tetrafluoroethylene-co-perfluoropropylvinylether)/graphene (PFA/GE) hollow fiber composite membranes (HFCMs) were prepared by dipping coating-thermal sintering coupling technique with a green process. GE is an emerging type of two-dimensional functional nanoparticle with a tunable passageway for oil molecules. The influences of the GE concentration in the casting solution on the structure and performance of the PBR-PFA/GE HFCMs were investigated. The results showed that the addition of GE produced a finger-like pore structure suitable for oil channels. Meanwhile, the roughness and contact angle of the composite membrane increased accordingly, and the water contact angle increased from 115 degrees to 120 degrees. The permeation fluxes of kerosene also increased obviously with the increase of GE contents, and the maximum flux of M-3 reached as high as 217.66 L & sdot;m- 2 & sdot;h- 1. The application of the lubricating oil flux test under working conditions of 60-150 degrees C has demonstrated the high-temperature oil permeability resistance of the composite membrane. Even after long-term use, its separation efficiency for water-in-oil emulsions still remains above 99.5 %. In addition, the membrane separation-efficiency both up to 99.9 % for activated carbon and silica dioxide (SiO2) in kerosene. Overall, the PBR-PFA/GE HFCMs with excellent lipophilicity presented great potential for oily wastewater treatment at high temperatures.