In this study, iron was coupled with copper to form a bimetallic compound through a biosynthetic method, which was then used as a catalyst in the Fenton-like processes for removing direct Blue 15 dye (DB15) from aqueous solution. Characterization techniques were applied on the resultant nanoparticles such as SEM, BET, EDAX, FT-IR, XRD, and zeta potential. Specifically, the rounded and shaped as spherical nanoparticles were found for green synthesized iron/copper nanoparticles (G-Fe/Cu NPs) with the size ranging from 32-59 nm, and the surface area was 4.452 m2/g. The effect of different experimental factors was studied in both batch and continuous experiments. These factors were H2O2 concentration, G-Fe/CuNPs amount, pH, initial DB15 concentration, and temperature in the batch system. The batch results showed 98% of 100 mg/L of DB15 was degraded with optimum H2O2 concentration, G-Fe/Cu-NPs dose, pH, and temperature 3.52 mmol/L, 0.7 g/L, 3, and 50℃ respectively. For the continuous mode, the influences of initial DB15 concentration, feed flow rate, G-Fe/Cu-NPs depth were investigated using an optimized experimental Box-Behnken design, while the conditions of pH and H2O2 concentration were based on the best value found in the batch experiments. The model optimization was set the parameters at 2.134 ml/min flow rate, 26.16 mg/L initial dye concentration, and 1.42 cm catalyst depth. All the parameters of the breakthrough curve were also studied in this study including break time, saturation time, length of mass transfer zone, the volume of bed, and volume effluent.
