Fenton-like degradation of direct blue dye using green synthesised Fe/Cu bimetallic nanoparticles

Abstract

This study relates to synthesizing the bentonite support iron/copper nanoparticles by biosynthesis method using eucalyptus plant leaves extract which was then named (E-Fe/Cu@B-NPs). The synthesized E-Fe/Cu@B-NPs were examined by a set of experiments of heterogeneous Fenton-like process through removing direct blue 15 dye (DB15) from wastewater. The characterization methods were employed on E-Fe/Cu@B-NPs by scanning electron microscopy (SEM), BET, zeta potential (ZP), Fourier transform infrared (FT-IR) spectroscopy and atomic force microscopy (AFM) on the resultant nanoparticles were also checked to ensure the functional groups of the E-Fe/Cu@B-NPs. Some of the operation condition parameters were optimized using Box-Behnken design (BBD) in the batch experiments, these parameters were pH, H₂O₂ dosage, E-Fe/Cu@B-NPs dosage, initial DB15 concentration, and temperature. The result showed that 94.32% of 57.5 mg/L of DB15 was degraded within 60 minutes with an optimum H₂O₂ dosage of 7.5 mmol/L, E-Fe/Cu@B-NPs dosage 0.55 g/L, pH 3.5, and temperature 50°C. The kinetic study indicated that the DB15 degradation kinetics were fitted to the second-order kinetic model and the thermodynamic factors proved the non-spontaneous, endothermic, and endergonic process with activation energy E _a of 62.961 kJ/mol.