Exploring treatment efficiency of graphene derivatives as adsorbents for removal of microplastics in water

Recent studies have shown that microplastic contamination is widespread throughout the world’s freshwater and oceans, with varying concentrations between highly populated and remote areas. Microplastic pollution has negative impacts on the environment, human, and aquatic life, and poses a threat to industries that rely on the marine environment to thrive. This work aims to investigate the adsorption of microplastics onto graphene-based materials (GBMs) and their potential application in water treatment. Various characterisation techniques were employed for the GBMs, including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier-Transform Infrared (FTIR) Spectroscopy. The batch adsorption tests were investigated for three GBMs: graphene oxide (GO), graphene foam (GF), and reduced graphene oxide (rGO), which demonstrated promising removal efficiencies of up to 70%, 60%, and 95%, with maximum adsorption capacities of 1960.98 mg/g, 1184.28 mg/g, and 922.36 mg/g, respectively. It was concluded that the initial microplastics concentrations were relatively high compared to the GBM dosage, leading to full saturation of active sites available for adsorption prior to reaching the complete removal of the contaminant. Overall, GO, GF, and rGO demonstrated considerable potential as adsorbents for microplastic removal.