Preparation and characterization of PVDF/PVP-GO membranes to be used in MBR system

Abstract

In this study, the effect of graphene oxide (GO) and polyvinylpyrrolidone (PVP) grafted GO (PVP-GO) on the hydrophilicity and antifouling properties of polyvinylidene fluoride (PVDF) was investigated. PVP-GO was synthesized via surface initiated free radical polymerization method. Successful immobilization of PVP on the GO surface was proved by FTIR and XRD analyses. FESEM results of PVP-GO nanosheets showed that immobilization increased interlayer space between nanosheets which resulted in better dispersion of PVP-GO in PVDF membranes. In addition, the presence of GO and PVP-GO nanosheets resulted in membranes with more and bigger finger-like pores and thinner sponge-like layer. Contact angle measurement, abrasion resistance and pure water flux of membranes containing different percentage of GO and PVP-GO ranging from 0 to 2 wt% were investigated. PVDF/GO (1.5 wt%) and PVDF/PVP-GO (1.5 wt%) showed the best hydrophilicity and pure water permeation and therefore, their performance was compared with neat PVDF in MBR system. The results indicated that the presence of GO and PVP-GO improved antifouling properties of PVDF membrane due to their hydrophilicity.