Microplastics (MPs) are fragments of any type of plastic less than 5mm in length, and it is harmful to our ocean and aquatic life. In recent years, the prevalence of MPs in aquatic environments has grown to be a serious environmental problem that has recently gained lots of attention [1, 2]. However, there is still a lack of studies on electrocatalytic treatment for an effective breakdown of MPs [3]. Here, Mxene-Metaloxide composites modified graphite electrode-based electro-fenton (EF) technology has been proposed to break down polyvinyl chloride (PVC) MPs. Advanced oxidation processes are widely studied and applied for the decomposition of MPs. Hydroxyl radicals (•OH) were generated by the electro-oxidation (EO) and electro-peroxidation (EO- ) process which has exhibited great capability for catalytic degradation of MPs and converted into H2O and CO2.In this work, electro-oxidation was carried out in a three-electrode system with an oxygen-saturated environment where Mxene-Metaloxide composites modified graphite electrode, graphite electrode, and Ag/AgCl electrode were used as a working electrode, counter electrode, and reference electrode respectively. Different operating parameters such as electrolyte type, electrolyte concentration, temperature, and reaction time were maintained for EO. Cyclic voltammetry was employed to analyze the catalytic performance of the MXene-TiO2/C modified graphite electrode in the context of the Oxygen Reduction Reaction. The obtained results revealed that the EO process can degrade 54.5% of MPs after potentiostatic electrolysis at -0.7V Ag/AgCl at 80 °C for 6 hours. Fig 1 presents the removal efficiency of PVC MPs in 0.05M Na2SO4 solution. The results from scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and Energy dispersive X-ray spectroscopy (EDX) revealed that the MPs degraded directly into CO2 and H2O. The results of this research showed that such a heterogeneous EF-like technology using Mxene-metal oxide composites modified graphite electrode was hoped to give an eco-friendly technique for treating MPs in wastewater.
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