Abstract:
Nanoplastics (NPs) in aquatic environments have gained considerable consideration
because of their persistent and adverse effects on the environment. Several methods have
been studied for their efficient removal from water bodies. This study assessed the
adsorption efficiency of magnetic graphene oxide in eliminating 80 nm sized polystyrene
NPs (PSNPs). Initially, the adsorption potential of graphene oxide and magnetic
nanoparticles were evaluated both separately and together through computational methods
using Material Studio. The adsorption process was simulated under NPT (constant number
of molecules, pressure, and temperature) conditions, The results indicated strong hydrogen
bonding interactions between the adsorbent and the PSNPs. In the next phase, magnetic
nanomaterials were synthesized by coating graphene oxide with iron oxide (Fe3O4) in the
laboratory. The morphological properties of the adsorbent were studied through SEM,
whereas the chemical nature was assessed using Energy Dispersive X-ray spectroscopy
(EDX), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD).
These analyses confirmed the successful synthesis of magnetic graphene oxide,
demonstrating its ability to effectively remove PSNPs from aqueous solutions. Furthermore,
the pH range between acidic and neutral conditions enhances the adsorption of PNPs, with
removal efficiencies of PSNPs lie between 81% at pH 3 to 77% at pH 7. Further, studies on
the adsorption mechanism, utilizing kinetic and isothermal models, revealed that
electrostatic attractions are the main forces driving the adsorption process. Adsorptiondesorption experiments showed that the adsorbent has excellent reusability, sustaining high
efficiency over four cycles. Our study highlights the potential of magnetic graphene oxide
as a robust and reusable adsorbent for the mitigation of NP removal from waterbodies
