Heterogeneous Fenton process using GO@Fe₃O₄/Cu catalyst for the degradation of reactive dyes from aqueous solutions: modeling and optimisation

ABSTRACT

Various industries such as textile, paper, rubber, plastic, and cosmetics use dyes to produce their products. Some dyes used in textile industries are teratogenic, carcinogenic, mutagenic, and dangerous for humans and other organisms. This study aimed to determine the amount of removal of reactive dyes from aqueous solutions during the heterogeneous Fenton process. In this study, iron oxide nanoparticles and copper nanoparticles were loaded on graphene oxide (GO). GO@Fe₃O₄/Cu catalyst was synthesised and applied to remove reactive dyes from aqueous solutions in a heterogeneous Fenton process. Contact time, pH, catalyst dose, dye concentration, and H₂O₂ dose were considered effective parameters. Experiments were designed according to the Box-Behnken design in the Design Expert software. Catalyst properties were determined using SEM, VSM, XRD, and FTIR analysis. The ANOVA showed that the selected statistical model with R² 0.965, p < 0.0001, and F-value 27.79 was significant. In the optimal conditions of pH 3, H₂O₂ dose 0.48 mL, catalyst dose 0.34 g/L, dye concentration 22 mg/L, and contact time 9 min, the degradation efficiency of Reactive Blue 21 (RB21), Reactive Red 195 (RR195) and Reactive Red 19 (RR19) were 92, 97, and 80%, respectively. The results showed that after 5 cycles of recycling, the catalyst had a high efficiency in pollutant removal and could be utilised many times for dye decomposition. GO@Fe₃O₄/Cu catalyst was successfully synthesised using a simple method. The heterogeneous Fenton process with a magnetic catalyst in the presence of H₂O₂ has a high potential to remove reactive dyes from the aqueous solution.

KEYWORDS:

• Reactive dye removal
• heterogeneous Fenton process
• GO@Fe₃O₄/Cu catalyst
• modeling

Acknowledgments

The authors would like to gratitude Shahid Sadoughi University of Medical Sciences for providing financial support for the present study (Grant No. 16175).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Shahid Sadoughi University of Medical Sciences, Iran [Grant No: 16175].