Graphene oxide quantum dots membrane: a hybrid filtration-advanced technology system to enhance process of wastewater reclamation

Abstract

The inability of wastewater treatment plants to effectively remove emerging pollutants has necessitated the need to develop newer advanced technologies. An integrated approach of combining advanced oxidation processes (AOPs) and membrane technologies promises superior performances. In this study, graphene oxide quantum dots-based membranes (GQDs-Ms) were fabricated via the phase inversion method. The GQDs-Ms revealed high oxygen content and a negative surface charge. The incorporating graphene oxide quantum dots (GQDs) into the polymer matrix led to enhanced hydrophilicity, pore size, porosity, improved flux as well as superior inhibition of Escherichia coli cells. A multi-AOPs approach was used in this work, wherein AOPs were applied as both pre-treatment (using GQDs) and post-treatment (combining GQDs with peracetic acid) in the disinfection of wastewater. The evaluation of GQDs-Ms performance was carried out and compared with a commercial membrane (Film Tec™NF270). The obtained % removals with GQDs-Ms were 83.45%, 64.12%, 40.76% and 70.36% for turbidity, total dissolved solids, total organic carbon and electrical conductivity, respectively, which compared nearly with commercial membrane’s performance. Interestingly, the integrated hybrid system can further remove and inactivate microbes in wastewater. The developed hybrid filtration-advanced technology system can substantially improve conventional wastewater treatment plants for water reuse.