Improved ultrafiltration performance and chlorine resistance of PVDF hollow fiber membranes via doping with sulfonated graphene oxide

摘要

Sulfonated grapheme oxide (SGO) nanohybrids were synthesized and employed to modify polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membranes accompanied with perfluorosulfonic acid (PFSA). Due to the synergism effects of PFSA and SGO, the SGO-blended PVDF membranes exhibit high permeability, anti-fouling performances and improved chemical resistance. SGO addition leads to thinner skin and porous sublayer of the membranes. The pure water permeability increases from 87.8 to 174.2 L.m(-2).bar(-1.)h(-1) by adding 0.5 wt% SGO nanohybrids in dope, and then slightly decreases to 156.2 L.m(-2).bar(-1).h(-1) for M1.0 with further addition to 1.0 wt%. After five fouling-cleaning cycles, SGO-modified PVDF membranes show less flux decline and more stable solute rejection than the unmodified one, which demonstrate that SGO nanosheets act as a chlorine barrier for the PVDF membranes, resulting in an outstanding anti-fouling ability and an effective suppression of the membrane degradation under frequent oxidative cleaning. (C) 2017 Elsevier B.V. All rights reserved.