Assessing the impact of dye characteristics on electrocoagulation efficiency in synthetic textile wastewater: An RSM-based study
DOI:
https://doi.org/10.31699/IJCPE.2026.3.9Keywords:
Synthetic wastewater; Electrocoagulation; COD removal; Dye type; Central Composite Design; Process optimization; Response Surface MethodologyAbstract
This new study investigates the effect that dye type cationic Methylene Blue (MB) and anionic Congo red (CR) that has on the Electro-coagulation (EC) treatment performance of synthetic wastewater by employing Response Surface Methodology-Central composite design (RSM- CCD) optimization technique. Twenty-seven experiments were performed to analyze and optimize the effects of 4 factors: Current Density (mA/cm²) = 6.67 - 13.33; Initial pH = 2 – 10; Reaction Time (h) = 0.07 – 1.5; and Chemical Oxygen Demand (COD mg /L) = 840 – 4236.67 mg/L. The efficiency of EC treatment is evaluated in terms of COD reduction as primary response variable. The RSM model accomplish an excellent predictive power (R2=98.84%; adjusted R2=97.48%); the experimental results illustrated a significant relationship between the estimated and measured values. The ANOVA analysis indicated that both current density and reaction time were primarily responsible for the most considerable effects on COD reduction. Furthermore, the study found that the initial pH had a critical role in forming and maintaining coagulating species. A maximum COD reduction efficiency of 98.14% was obtained under the best operating conditions as follows; current density of 11.11 mA/cm²(optimal), pH = 6 (initial) and reaction time = 1.5h and initial COD concentration of 2510 mg/L which also utilized only 8.89Wh / kg COD of the applied electrical energy. Many responses also had been tracked in this study to reflect the complex interaction between the operational variables and the final solution properties and its characteristics. The investigated properties changes were the final temperature, conductivity, voltage of the solution, in addition to the theoretical consumption of anode and specific energy consumption. A complex synergistic effect had been reported during the track of the solution characteristic, and this can be relied on the effect of dyes negative and positive charges that reflect some unusual behavior in comparison to the removal of single dyes, or dyes mixture of the same type.
Received on 19/06/2026
Received in Revised Form on 01/08/2026
Accepted on 01/08/2026
Published on 30/09/2026
References
[1] D. A. Yaseen and M. Scholz, “Textile dye wastewater characteristics and constituents of synthetic effluents: a critical review,” International Journal of Environmental Science and Technology, vol. 16, no. 2, pp. 1193–1226, Nov. 2018, https://doi.org/10.1007/s13762-018-2130-z
[2] X. Wang, J. Jiang, and W. Gao, “Reviewing textile wastewater produced by industries: characteristics, environmental impacts, and treatment strategies,” Water Science & Technology, vol. 85, no. 7, pp. 2076–2096, Mar. 2022, https://doi.org/10.2166/wst.2022.088
[3] M. M. Hassan and C. M. Carr, “A critical review on recent advancements of the removal of reactive dyes from dyehouse effluent by ion-exchange adsorbents,” Chemosphere, vol. 209, pp. 201–219, Jun. 2018, https://doi.org/10.1016/j.chemosphere.2018.06.043
[4] Y. Liu et al., “Environmental Impacts and Biological Technologies Toward Sustainable Treatment of Textile Dyeing Wastewater: A review,” Sustainability, vol. 16, no. 24, p. 10867, Dec. 2024, https://doi.org/10.3390/su162410867
[5] Y. Zhang, K. Shaad, D. Vollmer, and C. Ma, “Treatment of Textile Wastewater Using Advanced Oxidation Processes—A Critical Review,” Water, vol. 13, no. 24, p. 3515, Dec. 2021, https://doi.org/10.3390/w13243515
[6] G. Crini and E. Lichtfouse, “Advantages and disadvantages of techniques used for wastewater treatment,” Environmental Chemistry Letters, vol. 17, no. 1, pp. 145–155, Jul. 2018, https://doi.org/10.1007/s10311-018-0785-9
[7] M. Y. A. Mollah, R. Schennach, J. R. Parga, and D. L. Cocke, “Electrocoagulation (EC) — science and applications,” Journal of Hazardous Materials, vol. 84, no. 1, pp. 29–41, Jun. 2001, https://doi.org/10.1016/s0304-3894(01)00176-5
[8] J. N. Hakizimana et al., “Electrocoagulation process in water treatment: A review of electrocoagulation modeling approaches,” Desalination, vol. 404, pp. 1–21, Oct. 2016, https://doi.org/10.1016/j.desal.2016.10.011
[9] S. K. Ajjam, B. H. Hlih, and H. H. Alwan, “Enhancing lead ion removal from simulated wastewater through continuous electrocoagulation process: investigating operating parameters and adsorption behavior,” Chemical Papers, vol. 78, no. 18, pp. 9569–9579, Nov. 2024, https://doi.org/10.1007/s11696-024-03771-1
[10] A. Badejo et al., “Evaluating the performance of an electrocoagulation process using response surface methods for textile wastewater treatment,” Engineering and Technology Journal, vol. 0, no. 0, pp. 1–9, Aug. 2025, http://doi.org/10.30684/etj.2025.161784.1974
[11] M. Kobya, E. Gengec, M. T. Sensoy, and E. Demirbas, “Treatment of textile dyeing wastewater by electrocoagulation using Fe and Al electrodes: optimisation of operating parameters using central composite design,” Coloration Technology, vol. 130, no. 3, pp. 226–235, Apr. 2014, https://doi.org/10.1111/cote.12090
[12] P. P. Das, M. Sharma, and M. K. Purkait, “Recent progress on electrocoagulation process for wastewater treatment: A review,” Separation and Purification Technology, vol. 292, p. 121058, Apr. 2022, https://doi.org/10.1016/j.seppur.2022.121058
[13] S. K. Ajjam, M. A. Aljaleel, B. H. Hlihl, and H. H. Alwan, “Nitrate removal from simulated wastewater by electrocoagulation: Impact of operating parameters on removal efficiency and energy consumption,” South African Journal of Chemical Engineering, vol. 55, pp. 1–10, Oct. 2025, https://doi.org/10.1016/j.sajce.2025.10.002
[14] M. Ebba, P. Asaithambi, and E. Alemayehu, “Development of electrocoagulation process for wastewater treatment: optimization by response surface methodology,” Heliyon, vol. 8, no. 5, p. e09383, May 2022, https://doi.org/10.1016/j.heliyon.2022.e09383
[15] K. Faheem, S. U. Khan, M. Washeem, and S. U. Khan, “Energy efficient removal of COD from landfill leachate wastewater using electrocoagulation: parametric optimization using RSM,” International Journal of Environmental Science and Technology, vol. 19, no. 5, pp. 3625–3636, Apr. 2022, https://doi.org/10.1007/s13762-021-03277-3
[16] J. S. Al-Marri, A. B. Abouedwan, M. I. Ahmad, and N. Bensalah, “Electrocoagulation using aluminum electrodes as a sustainable and economic method for the removal of kinetic hydrate inhibitor (polyvinyl pyrrolidone) from produced wastewaters,” Frontiers in Water, vol. 5, Dec. 2023, https://doi.org/10.3389/frwa.2023.1305347
[17] A. Shahedi, A. K. Darban, F. Taghipour, and A. Jamshidi-Zanjani, “A review on industrial wastewater treatment via electrocoagulation processes,” Current Opinion in Electrochemistry, vol. 22, pp. 154–169, Jun. 2020, https://doi.org/10.1016/j.coelec.2020.05.009
[18] Y. Mao, Y. Zhao, and S. Cotterill, “Examining current and future applications of electrocoagulation in wastewater treatment,” Water, vol. 15, no. 8, p. 1455, Apr. 2023, https://doi.org/10.3390/w15081455
[19] M. Romani, F. R. Espinoza-Quiñones, A. N. Módenes, and C. E. Borba, “New insights into the improvement of electrocoagulation performance on the basis of a time-integrated performance index: The pivotal role of electrical conductivity,” Journal of Environmental Chemical Engineering, vol. 8, no. 4, p. 103902, Apr. 2020, https://doi.org/10.1016/j.jece.2020.103902
[20] P. T. P. Aryanti, F. A. Nugroho, C. Phalakornkule, and A. Kadier, “Energy efficiency in electrocoagulation processes for sustainable water and wastewater treatment,” Journal of Environmental Chemical Engineering, vol. 12, no. 6, p. 114124, Sep. 2024, https://doi.org/10.1016/j.jece.2024.114124
[21] D. Selvaraj and M. Arivazhagan, “An Integrated (Electrocoagulation and Adsorption) approach for the treatment of textile industrial wastewater: RSM and ANN based optimization,” Water Air & Soil Pollution, vol. 235, no. 1, Dec. 2024, https://doi.org/10.1007/s11270-023-06840-5
[22] N. Acharya, C. Thakur, and P. K. Chaudhari, “Dataset on statistical reduction of COD by electrocoagulation process using RSM,” Data in Brief, vol. 28, p. 104944, Dec. 2020, https://doi.org/10.1016/j.dib.2019.104944
[23] A. S. Naje, S. Chelliapan, Z. Zakaria, M. A. Ajeel, and P. A. Alaba, “A review of electrocoagulation technology for the treatment of textile wastewater,” Reviews in Chemical Engineering, vol. 33, no. 3, Nov. 2016, https://doi.org/10.1515/revce-2016-0019
[24] G. Mouedhen, M. Feki, M. De Petris Wery, and H. F. Ayedi, “Behavior of aluminum electrodes in electrocoagulation process,” Journal of Hazardous Materials, vol. 150, no. 1, pp. 124–135, Apr. 2008, https://doi.org/10.1016/j.jhazmat.2007.04.090
[25] Z. Gu, Z. Liao, M. Schulz, J. R. Davis, J. C. Baygents, and J. Farrell, “Estimating dosing rates and energy consumption for electrocoagulation using iron and aluminum electrodes,” Industrial & Engineering Chemistry Research, vol. 48, no. 6, pp. 3112–3117, Feb. 2009, https://doi.org/10.1021/ie801086c
Downloads
Published
Issue
Section
License
Copyright (c) 2026 The Author(s). Published by College of Engineering, University of Baghdad.
This work is licensed under a Creative Commons Attribution 4.0 International License.
