High performance graphene oxide/polyacrylonitrile composite pervaporation membranes for desalination applications

Abstract

As an emerging technology, pervaporation (PV) has shown great promise in fresh water production from salty water. However, the low separation efficiencies of the present membranes hinder their practical applications. Here, thin graphene oxide (GO) films with 2D nanochannels were fabricated on polyacrylonitrile (PAN) ultrafiltration membranes using a vacuum filtration-assisted assembly method. The GO/PAN composite membrane exhibits a high water flux of up to 65.1 L m⁻² h⁻¹ with high rejection (about 99.8%) for desalination by pervaporation at 90 °C. It is noteworthy that the composite membranes show high performances in treating high-salinity water, even at salt concentrations of up to 100 000 ppm. This makes it possible to use GO-based membranes for seawater desalination, brackish water desalination and reverse osmosis concentrate treatment.