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Enhanced Electro-Degradation of Direct Black 38 Dye Using Copper Oxide–Modified Graphite Electrode and CaCl₂ as Supporting Electrolyte

Department of Chemistry Education, Faculty of Mathematics and Natural Science, Universitas Negeri Yogyakarta, Yogyakarta, Indonesia

Received: 19 Aug 2025; Revised: 1 Jan 2026; Accepted: 2 Jan 2026; Published: 7 Feb 2026.
Open Access Copyright 2026 Jurnal Kimia Sains dan Aplikasi under http://creativecommons.org/licenses/by-sa/4.0.

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Abstract

The dyes used in the textile industry generate substantial waste, posing significant environmental hazards. Because textile industries discharge large amounts of effluents, it is essential to develop effective methods to reduce the presence of reactive textile dyes. This work evaluated the removal of Direct Black 38 (DB-38) using the bare graphite electrode (GE) modified by copper oxide to form a graphite/Cu/Cu-oxide (GE/Cu/Cu-oxide). The electrode was prepared by electrodeposition. Electro-degradation of 50 ppm DB-38 dye was conducted at different applied potentials, reaction times, and CaCl2 concentrations as supporting electrolytes. The X-ray diffraction patterns showed the highest peak at 2θ = 36.55, corresponding to graphite/Cu2O, and at 2θ = 38.73, corresponding to graphite/CuO. The GE/Cu/Cu-oxide electrode is eleven times more reactive than bare graphite. The GE/Cu/Cu-oxide electrode achieved a 99.08% electro-degradation efficiency of DB-38, with a reduction of 97.50% in COD, and 40.60% in TDS after 60 minutes, when 0.03 M CaCl2 was used as the supporting electrolyte at a potential 12 V. Thus, the proposed process demonstrated promising results for dye treatment in various aqueous matrices, utilizing low-cost, readily available electrodes that have not been previously applied for this purpose.

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Keywords: Direct Black 38; electro-degradation; electrode modified; graphite; CaCl₂

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  1. Charan Kumar H. C., Shilpa R., RaviShankar Rai V., Ananda S., Electrochemical Degradation of Indigo Carmine Dye at Ru/graphite Modified Electrode in Aqueous Solution, IOSR Journal of Applied Chemistry, 10, 12, (2017), 47-61
  2. Benkhaya Benkhaya, Sara El Harfi, Ahmed El Harfi, Classifications, properties and applications of textile dyes: A review, Applied Journal of Environmental Engineering Science, 3, 3, (2017), 311-320 https://doi.org/10.48422/IMIST.PRSM/ajees-v3i3.9681
  3. Zaina Rohayati, Mega M. Fajrin, Jumardin Rua, Yulan Yulan, Riyanto Riyanto, Pengolahan Limbah Industri Tekstil Berbasis Green Technology Menggunakan Metode Gabungan Elektrodegradasi dan Elektrodekolorisasi dalam Satu Sel Elektrolisis, Chimica et Natura Acta, 5, 2, (2017), 95-100 https://doi.org/10.24198/cna.v5.n2.14702
  4. Mohammad Molla Mahmoudi, Azam Nadali, Hamid Reza Soheil Arezoomand, Amir Hossein Mahvi, Adsorption of cationic dye textile wastewater using Clinoptilolite: isotherm and kinetic study, The Journal of The Textile Institute, 110, 1, (2019), 74-80 https://doi.org/10.1080/00405000.2018.1465329
  5. Esra Yeliz Altun, Zehra Tuba Şİşmanoğlu, Gülin Selda Pozan Soylu, Photocatalytic decomposition of textile dyestuffs by photosensitive metal oxide catalysts, Turkish Journal of Chemistry, 45, 5, (2021), 1432-1443 https://doi.org/10.3906/kim-2104-30
  6. M. El Hajji, A. Baddouh, M. Rghuiti, O. Jbara, A. Tara, L. Bazzi, A. Benlhachemi, M. Hilali, Electrochemical degradation of organic dye by electrochemical oxidation on a Ti/Cu2O electrode, Applied Journal of Environmental Engineering Science, 1, 1, (2016), 1-8 https://doi.org/10.48422/IMIST.PRSM/ajees-v1i1.7076
  7. Rajvir Kaur, Harpreet Kaur, Electrochemical Degradation of Congo Red from Aqueous Solution: Role of Graphite Anode as Electrode Material, Portugaliae Electrochimica Acta, 34, 3, (2016), 185-196
  8. S. Manikandan, R. Saraswathi, Electrocoagulation technique for removing Organic and Inorganic pollutants (COD) from the various industrial effluents: An overview, Environmental Engineering Research, 28, 4, (2023), 220231 https://doi.org/10.4491/eer.2022.231
  9. Prakash Kariyajjanavar, Jogttappa Narayana, Yanjerappa Arthoba Nayaka, Degradation of textile wastewater by electrochemical method, Hydrology: Current Research, 2, 1, (2011), 1-7 http://dx.doi.org/10.4172/2157-7587.1000110
  10. Emma Roubaud, Rémy Lacroix, Serge Da Silva, Jérôme Esvan, Luc Etcheverry, Alain Bergel, Régine Basséguy, Benjamin Erable, Industrially scalable surface treatments to enhance the current density output from graphite bioanodes fueled by real domestic wastewater, iScience, 24, 3, (2021), 102162 https://doi.org/10.1016/j.isci.2021.102162
  11. Chandrashekar Chandrashekar, Charan Kumar H. C., Raghavendra M. P., Prashanth P. A., Shilpa R., Ananda S., Electrochemical degradation of 5,5- indigodisulfonic acid sodium salt dye at copper/graphite modified electrode in aqueous solution, International Journal of Creative Research Thoughts, 10, 7, (2022), 223355
  12. Ingrid Larissa da Silva Santana, Marina Gomes Silva, Naiana Santos da Cruz Santana Neves, Fernanda Sobreira Silva, Mariana Alves Henrique, Jorge Vinícius Fernandes Lima Cavalcanti, Ramon Raudel Pena Garcia, Joan Manuel Rodríguez-Diaz, Marta Maria Menezes Bezerra Duarte, Daniella Carla Napoleão, Electrodegradation of direct black 22 in textile effluents using graphite and copper electrodes, Applied Catalysis O: Open, 188, (2024), 206925 https://doi.org/10.1016/j.apcato.2024.206925
  13. P. V. Nidheesh, Minghua Zhou, Mehmet A. Oturan, An overview on the removal of synthetic dyes from water by electrochemical advanced oxidation processes, Chemosphere, 197, (2018), 210-227 https://doi.org/10.1016/j.chemosphere.2017.12.195
  14. Md. Saiful Alam, Mohammad Imran Hossain, Md Abdul Malek, Nayan Ranjan Singha, Merajuddin Khan, Mostafizur Rahaman, Jamal Uddin, Mohammad A. Hasnat, Electrochemical Generation of Reactive Chlorine Species via Chloride Oxidation on –COOH-Modified Graphite Electrode to Attain Dye Degradation, Catalysts, 15, 11, (2025), 1046 https://doi.org/10.3390/catal15111046
  15. Noémie Elgrishi, Kelley J. Rountree, Brian D. McCarthy, Eric S. Rountree, Thomas T. Eisenhart, Jillian L. Dempsey, A Practical Beginner’s Guide to Cyclic Voltammetry, Journal of Chemical Education, 95, 2, (2018), 197-206 https://doi.org/10.1021/acs.jchemed.7b00361
  16. Vijayalakshmi Radhakrishnan, Green Synthesis and Characterisation of Copper Oxide Nanoparticles - Reduced Graphene Oxide Nano Composites for Facile Electrochemical Oxidation of Ponceau 4R and Alizarin Red Dyes in Aqueous Medium, Journal of Water and Environmental Nanotechnology, 6, 3, (2021), 241-251 https://doi.org/10.22090/jwent.2021.03.005
  17. Jonghun Lim, Michael R. Hoffmann, Substrate oxidation enhances the electrochemical production of hydrogen peroxide, Chemical Engineering Journal, 374, (2019), 958-964 https://doi.org/10.1016/j.cej.2019.05.165
  18. Fatna Eddaqaq, Brahim Lekhlif, Adil Dani, Abdelkbir Errougui, Mhammed El Kouali, Samir Chtita, Investigation of Surface Water Treatment via Integration of Internal Loop Airlift System and Electrocoagulation-flotation with CaCl2 and NaCl as Electrolytes, Physical Chemistry Research, 12, 4, (2024), 1065-1077 https://doi.org/10.22036/pcr.2024.450884.2509
  19. SangYup Lee, Sujin Seong, Seunga Yang, Soon-Ki Jeong, Mechanism-Informed Interfacial Chemistry and Structural Evolution of TiS2 During Ca2+ Intercalation in Concentrated Aqueous CaCl2 Electrolytes, International Journal of Molecular Sciences, 26, 24, (2025), 11971 https://doi.org/10.3390/ijms262411971
  20. Ni Made Wiratini, Triyono Triyono, Wega Trisunaryanti, Agus Kuncaka, Graphite/NiO/Ni Electrode for Electro-oxidation of the Remazol Black 5 Dye, Bulletin of Chemical Reaction Engineering & Catalysis, 16, 4, (2021), 847-856 https://doi.org/10.9767/bcrec.16.4.11702.847-856
  21. Gubernur Daerah Istimewa Yogyakarta, Peraturan Daerah Istimewa Yogyakarta No. 7 Tahun 2016 tentang baku mutu air limbah, 2016,
  22. Marwan Khalish, Ayu Utami, Herwin Lukito, Susila Herlambang, Evaluation of Textile Industry Wastewater Treatment as an Effort to Control River Water Pollution in Central Java, KnE Life Sciences, 7, 3, (2022), 48–61 https://doi.org/10.18502/kls.v7i3.11106

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