Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights

Nawid Ahmad Akhtar; Nevin Atalay Gengeç; Mehmet Kobya; Erhan Gengec

doi:10.51354/mjen.1767592

EN

Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights

Abstract

The Acid Orange 7 (AO7) azo dye poses a serious problem due to its low environmental persistence and low treatment efficiency. Electrooxidation (EO) is a sustainable and highly efficient treatment technology for the effective oxidation of toxic AO7 azo dye. In this study, we investigated key parameters of the EO process for the oxidation of the AO7 azo dye, including current density (j), initial pH, initial AO7 concentration (Ci), and supporting electrolyte concentration (SEc). Under optimal operating conditions (anode/cathode = Pt/Gr-PtO2, j = 100 A/m2, pH = 3, Ci = 35 mg/L, and Na2SO4 = 50 mM), a removal efficiency of 79.0 % was achieved. Under the same conditions, the energy consumption and operating costs were calculated as 3.21 kWh/m3 (1471.82 kWh/kg AO7) and 0.57 $/m3 (11.96 $/kg AO7), respectively. Furthermore, the first-order model was evidenced by the determination of correlation coefficient values of (R2 = 0.984, AdjustedR2 = 0.963) and rate constant k = 0.00812 𝑚𝑖𝑛−1. These findings demonstrate that the EO process offers an effective and economical solution for removing AO7 azo dye, thereby supporting the potential of advanced oxidation technologies in environmental engineering.

Keywords

Acid orange, electrooxidation, kinetic mechanism, process optimization, energy consumption

Project Number

115Y305

Ethical Statement

The authors state that this research adheres to the ethical standards. This research does not involve either human participants or animals.

Thanks

This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under the project “The production of graphene and graphene-metal composites anodes and the removal of organic pollutants from water by electro-oxidation with produced anodes” (Project No: 115Y305).

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Details

Primary Language

English

Subjects

Waste Management, Reduction, Reuse and Recycling, Clean Production Technologies, Wastewater Treatment Processes, Water Treatment Processes

Journal Section

Research Article

Authors

Nawid Ahmad Akhtar ^*
0009-0006-5390-7505
Kyrgyzstan

Nevin Atalay Gengeç
0000-0003-0993-4398
Türkiye

Mehmet Kobya
0000-0001-5052-7220
Türkiye

Erhan Gengec
0000-0003-3666-0791
Türkiye

Publication Date

June 30, 2026

Submission Date

August 17, 2025

Acceptance Date

June 22, 2026

Published in Issue

Year 2026 Volume: 14 Number: 1

DOI

https://doi.org/10.51354/mjen.1767592

IZ

https://izlik.org/JA37TS95BF

APA

Akhtar, N. A., Atalay Gengeç, N., Kobya, M., & Gengec, E. (2026). Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights. MANAS Journal of Engineering, 14(1), 54-65. https://doi.org/10.51354/mjen.1767592

AMA

1.Akhtar NA, Atalay Gengeç N, Kobya M, Gengec E. Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights. MJEN. 2026;14(1):54-65. doi:10.51354/mjen.1767592

Chicago

Akhtar, Nawid Ahmad, Nevin Atalay Gengeç, Mehmet Kobya, and Erhan Gengec. 2026. “Electrochemical Degradation of Acid Orange 7 Azo Dye: Process Optimization, Reaction Kinetics, and Mechanistic Insights”. MANAS Journal of Engineering 14 (1): 54-65. https://doi.org/10.51354/mjen.1767592.

EndNote

Akhtar NA, Atalay Gengeç N, Kobya M, Gengec E (June 1, 2026) Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights. MANAS Journal of Engineering 14 1 54–65.

IEEE

[1]N. A. Akhtar, N. Atalay Gengeç, M. Kobya, and E. Gengec, “Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights”, MJEN, vol. 14, no. 1, pp. 54–65, June 2026, doi: 10.51354/mjen.1767592.

ISNAD

Akhtar, Nawid Ahmad - Atalay Gengeç, Nevin - Kobya, Mehmet - Gengec, Erhan. “Electrochemical Degradation of Acid Orange 7 Azo Dye: Process Optimization, Reaction Kinetics, and Mechanistic Insights”. MANAS Journal of Engineering 14/1 (June 1, 2026): 54-65. https://doi.org/10.51354/mjen.1767592.

JAMA

1.Akhtar NA, Atalay Gengeç N, Kobya M, Gengec E. Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights. MJEN. 2026;14:54–65.

MLA

Akhtar, Nawid Ahmad, et al. “Electrochemical Degradation of Acid Orange 7 Azo Dye: Process Optimization, Reaction Kinetics, and Mechanistic Insights”. MANAS Journal of Engineering, vol. 14, no. 1, June 2026, pp. 54-65, doi:10.51354/mjen.1767592.

Vancouver

1.Nawid Ahmad Akhtar, Nevin Atalay Gengeç, Mehmet Kobya, Erhan Gengec. Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights. MJEN. 2026 Jun. 1;14(1):54-65. doi:10.51354/mjen.1767592

Manas Journal of Engineering

16155

Abstract

Project Number

Electrochemical degradation of acid orange 7 azo dye: process optimization, reaction kinetics, and mechanistic insights

Abstract

Keywords

Project Number

Ethical Statement

Thanks

References

Details

Primary Language

Subjects

Journal Section

Authors

Publication Date

Submission Date

Acceptance Date

Published in Issue

DOI

IZ

Cite