Polystyrene infused with functionalized reduced graphene oxide as a reusable oil sorbent

Abstract

Adsorption has been reported to be optimal among oil spill cleanup methods due to its simplicity, low capital and operational cost, high removal efficiency and environmental friendliness. However, its continuous usage has been linked to generation of enormous waste, after oil spill cleanup, to which use of reusable oil sorbents has been proposed as a possible solution. Synthetic organic oil sorbents have high mechanical properties compared to other categories of oil sorbents, but they suffer low adsorptive capacities. To address this problem, among other nanoparticles, rGO have been infused in polymeric materials to produce composite oil sorbents characterized with high adsorptive capacities. In this research, surface modified rGO was infused in waste expanded polystyrene, to produce electrospun PS/FrGO composite sorbents by solution blending and electrospinning method. Adsorptive capacities of produced composites were evaluated in four oil samples. Functionalization of rGO was found to cause removal of residual oxygen containing functional groups such as hydroxyl (–OH), and resulted in more hydrophobic surface. Infusion of FrGO, in waste expanded polystyrene resulted into composites with increased surface area, from 71.50 m2/g for pure PS20 to 353.45 m2/g, 429.18 m2/g, 456.14 m2/g for PS20 infused with 1, 2 and 4wt% of FrGO. Increase in oil sorption capacities of the composite, observed in four oil samples corresponds to improved surface area. Produced composites show good recyclability in the four oil samples, at least up to the third sorption cycle.