Fabrication, Characterization, and Testing of Graphene Oxide and Hydrophilic Polymer Graphene Oxide Composite Membranes in a Dead-End Flow System

Abstract

Graphene oxide (GO) has emerged as a promising material for next-generation water treatment membranes. In this study, three types of GO membranes were produced and tested. Both GO and graphene oxide plus polyvinyl alcohol (GO/PVA) membranes were produced using the vacuum-assisted self-assembly (VASA) method, and a chitosan and graphene oxide composite membrane (CSGO) was assembled using GO as a nanoscale filler via evaporation under reduced pressure. Scanning electron micrographs (SEMs) confirmed that GO and GO/PVA membranes were particularly well ordered, whereas CSGO exhibited reduced ordering attributed to structural and composition differences of GO and CS. The fabricated membranes were tested in a dead-end flow system indicating that each membrane containing GO produced a higher flux at 413 kPa pressure relative to conventional polyamide reverse osmosis (RO) membranes used for benchmark comparison, but was lower in flux to a nanofiltration (NF) membrane. Challenging the membranes with 7.5 mg/L methylene blue solution resulted in ≥ 97.5% removal of the dye by all three of the membranes.