Document Type : Research Paper
Authors
Department of Chemical Engineering, Faculty of Engineering, Kermanshah University of Technology, Kermanshah, Iran
Abstract
This study investigates the efficiency of the photo-Fenton process in removing Congo red dye from synthetic wastewater. Considering the importance of eliminating colored pollutants from the environment, this research examines the effect of key operational parameters, including Fe2O3 concentration (10, 30, and 50 mg/L), hydrogen peroxide concentration (100, 300, and 500 mg/L), process time (30, 60, and 90 min), and initial Congo red dye concentration (10, 30, and 50 mg/L), on the percentage of dye removal in the photo-Fenton process. The experiments were conducted in a glass reactor using a UV-C lamp as the radiation source, at ambient temperature and with a stirring speed of 350 rpm. To optimize the process and examine the interaction of parameters, the Box-Behnken experimental design method was used, and 27 experiments were designed and performed randomly. Analysis of variance on the results showed that the proposed quadratic model has acceptable accuracy for predicting dye removal efficiency. Furthermore, examination of contour plots revealed that Fe2O3 concentration and initial Congo red dye concentration have the greatest impact on process efficiency. Finally, the optimal conditions for achieving the maximum percentage of dye removal from synthetic wastewater were determined. Under optimal conditions (process time of 30 min, hydrogen peroxide concentration of 100 mg/L, Fe2O3 concentration of 40.99 mg/L, and initial Congo red concentration of 30 mg/L), the maximum Congo red removal efficiency of 99.59% was achieved.
Keywords
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Ain, Q. U. et al. (2024) 'Activation of Fe3O4/bentonite through anchoring of highly dispersed and photo-reduced Cu ions for higher pH fenton-like degradation and effective adsorption of Congo red dye', Journal of Industrial and Engineering Chemistry, 134, pp. 327-342. doi: https://doi.org/10.1016/j.jiec.2023.12.062
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Bouras, H. D. et al. (2019) 'Photocatalytic oxidation of azo dye solutions by impregnation of ZnO on fungi', Biochemical Engineering Journal, 146, pp. 150-159. doi: https://doi.org/10.1016/j.bej.2019.03.014
Da Silva Brito, G. F. et al. (2019) 'Evaluation of advanced oxidative processes in biodiesel wastewater treatment', Journal of Photochemistry and Photobiology A: Chemistry, 375, pp. 85-90. doi: https://doi.org/10.1016/j.jphotochem.2019.01.013
Fuentes-Gandara, F. et al. (2024) 'Removal of direct navy blue dye from aqueous solutions using banana peels', Global Journal of Environmental Science and Management, 10(3), pp. 1067-1084. doi: https://doi.org/10.22034/gjesm.2024.03.09
Ghribi, A. and Bagane, M. (2023) 'Removal of Congo Red and Rhodamine B dyes from aqueous solution by Fenton process: Optimization of operational parameters', Iranian Journal of Chemistry and Chemical Engineering, 42(3), pp. 801-809. doi: https://doi.org/10.30492/ijcce.2022.545521.5077
Gökdað, S. et al. (2025) 'Synthesis of a novel supermagnetic Fe3O4 nanoparticles and their Congo Red dye removal, cytotoxic, antioxidant, and antimicrobial activities', Plasmonics, 20(9), pp. 7527–7545. doi: https://doi.org/10.1007/s11468-025-02779-x
Habeeb, S. A., Zinatizadeh, A. A. and Zangeneh, H. (2023) 'Photocatalytic decolorization of direct Red16 from an aqueous solution using B-ZnO/TiO2 nano photocatalyst: synthesis, characterization, process modeling, and optimization', Water, 15(6), pp. 1203. doi: https://doi.org/10.3390/w15061203
Jiménez, S. et al. (2019) 'Produced water treatment by advanced oxidation processes', Science of the Total Environment, 666, pp. 12-21. doi: https://doi.org/10.1016/j.scitotenv.2019.02.128
Khanbolouk, F. et al. (2025) 'Cost-effective synthesis of gamma alumina for propane dehydrogenation: a study of raw materials, process optimization, and catalyst performance', Chemical Methodologies, 9(10), pp. 904-921. doi: https://doi.org/10.48309/chemm.2025.521098.1954
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Mansour, D. et al. (2024) 'Removal of Congo red dye by electrochemical advanced oxidation process: optimization, degradation pathways, and mineralization', Sustainable Water Resources Management, 10(1), pp. 41. doi: https://doi.org/10.1007/s40899-023-01022-x
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Mohadesi, M. et al. (2024b) 'Simultaneous removal of Pb (II) and Cr (VI) from a steel company wastewater using various green adsorbents: material characterization and numerical optimization', Water Practice & Technology, 19(11), pp. 4473-4485. doi: https://doi.org/10.2166/wpt.2024.266
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Samimi, M. and Moeini, S. (2020) 'Optimization of the Ba+2 uptake in the formation process of hydrogels using central composite design: Kinetics and thermodynamic studies of malachite green removal by Ba-alginate particles', Journal of Particle Science and Technology, 6(2), pp. 95-102. doi: https://doi.org/10.22104/jpst.2021.4842.1184
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Sattar, O. D. A., Khalid, R. M. and Yusoff, S. F. M. (2024) 'Electromagnetic pre-treatment for extraction of bitter orange peel pectin: Response surface methodology yield/degree of esterification', Chemical Methodologies, 8(3), pp. 217-233. doi: https://doi.org/10.48309/chemm.2024.437672.1760
Shaban, M. et al. (2017) 'Photocatalytic degradation and photo-Fenton oxidation of Congo red dye pollutants in water using natural chromite—response surface optimization', Applied Water Science, 7(8), pp. 4743-4756. doi: https://doi.org/10.1007/s13201-017-0637-y
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Sirés, I. et al. (2014) 'Electrochemical advanced oxidation processes: today and tomorrow. A review', Environmental Science and Pollution Research, 21(14), pp. 8336-8367. doi: https://doi.org/10.1007/s11356-014-2783-1
Zhou, H. et al. (2022) 'Efficient degradation of Congo red in water by UV-vis driven CoMoO4/PDS photo-fenton system', Molecules, 27(24), pp. 8642. doi: https://doi.org/10.3390/molecules27248642
Phan, T. T. N. and Nguyen, T. T. H. (2024) 'Adsorptive removal and photo-fenton degradation of Congo Red dye from water using modified gadolinium orthoferrite', JST: Engineering and Technology For Sustainable Development, 34(3), pp. 1-7. doi: https://doi.org/10.51316/jst.175.etsd.2024.34.3.1
Raghav, S., Painuli, R. and Kumar, D. (2018) 'Threats to water: Issues and challenges related to ground water and drinking water', In: Naushad, M. (ed.) A New Generation Material Graphene: Applications in Water Technology, Switzerland: Springer Cham, pp. 1-19. doi: https://doi.org/10.1007/978-3-319-75484-0_1
Salameh, S. et al. (2026) 'Combined removal of Pemetrexed drug using adsorption and photocatalytic degradation from polluted water', Advanced Journal of Chemistry, Section A, 9(2), pp. 155-165. doi: https://doi.org/10.48309/ajca.2026.531785.1874
Samimi, M. (2024) 'Efficient biosorption of cadmium by Eucalyptus globulus fruit biomass using process parameters optimization', Global Journal of Environmental Science and Management, 10(1), pp. 27-38. doi: https://doi.org/10.22034/gjesm.2024.01.03
Samimi, M. (2025) 'Synthesis of alginate–based biocomposite containing biomass derived from Lantana camara L. stem as a novel biopolymeric sorbent for methylene blue uptake', Chemical Methodologies, 9(11), pp. 1054-1068. doi: https://doi.org/10.48309/chemm.2025.527953.1969
Samimi, M. and Amiri, K. (2024) 'Zinc alginate beads as an effective biosorbent for the removal of Eosin-B from aquatic solutions: Equilibrium, kinetics, and thermodynamic behaviors', Chemical Methodologies, 8(5), pp. 351-363. doi: https://doi.org/10.48309/chemm.2024.454717.1791
Samimi, M. and Moeini, S. (2020) 'Optimization of the Ba+2 uptake in the formation process of hydrogels using central composite design: Kinetics and thermodynamic studies of malachite green removal by Ba-alginate particles', Journal of Particle Science and Technology, 6(2), pp. 95-102. doi: https://doi.org/10.22104/jpst.2021.4842.1184
Samimi, M. and Moghadam, H. (2024) 'Modified evacuated tube collector basin solar still for optimal desalination of reverse osmosis concentrate', Energy, 289, pp. 129983. doi: https://doi.org/10.1016/j.energy.2023.129983
Samimi, M. and Nouri, J. (2025) 'Optimized removal of trivalent arsenic from aquatic environments using Prosopis juliflora seed biomass', Global Journal of Environmental Science and Management, 11(2), pp. 391-402. doi: https://doi.org/10.22034/gjesm.2025.02.02
Sattar, O. D. A., Khalid, R. M. and Yusoff, S. F. M. (2024) 'Electromagnetic pre-treatment for extraction of bitter orange peel pectin: Response surface methodology yield/degree of esterification', Chemical Methodologies, 8(3), pp. 217-233. doi: https://doi.org/10.48309/chemm.2024.437672.1760
Shaban, M. et al. (2017) 'Photocatalytic degradation and photo-Fenton oxidation of Congo red dye pollutants in water using natural chromite—response surface optimization', Applied Water Science, 7(8), pp. 4743-4756. doi: https://doi.org/10.1007/s13201-017-0637-y
Sharifi, N. and Mohadesi, M. (2024) 'Textile wastewater treatment using solar photo-Fenton process', International Journal of Environmental Science and Technology, 21(3), pp. 2709-2722. doi: https://doi.org/10.1007/s13762-023-05397-4
Sirés, I. et al. (2014) 'Electrochemical advanced oxidation processes: today and tomorrow. A review', Environmental Science and Pollution Research, 21(14), pp. 8336-8367. doi: https://doi.org/10.1007/s11356-014-2783-1
Zhou, H. et al. (2022) 'Efficient degradation of Congo red in water by UV-vis driven CoMoO4/PDS photo-fenton system', Molecules, 27(24), pp. 8642. doi: https://doi.org/10.3390/molecules27248642
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