Efficient degradation of phenol by electrooxidation process at boron-doped diamond anode system

Abstract

The rapid increase in global population and industrialization has led to increased environmental pollution, primarily due to insufficient treatment technologies and the depletion of freshwater resources. This research investigates the impact of the electrooxidation (EO) process using Boron Doped Diamond (BDD) anode on phenol degradation, energy consumption, total operating costs, and anode efficiency. The study was carried out on different current densities (j = 50-200 A/m2), initial pH (3.6-9.6), initial phenol concentration (Ci = 100-800 mg/L), and supporting electrolyte concentration (SEc = 2-6 g NaCl/L). The phenol removal efficiency under optimum conditions (anode = BDD, j = 200 A/m2, initial pH = 7.6, Cphenol = 100 mg/L, and SEc = 4 g NaCl/L) was determined to be 100% after 50 min of EO reaction time. However, the energy consumption and total operating cost under these conditions were 12.7 kWh/m3 (420 kWh/kg phenol) and 0.99 $/m3 (7.88 $/kg phenol), respectively. Moreover, BDD anode efficiencies were calculated as 6.39, 3.47, and 1.74 g phenol/Ahm2 at current densities of 50, 100, and 200 A/m2, respectively. Consequently, the EO process is a more cost-effective treatment approach for efficient phenol removal from an aqueous solution.

Keywords

• Phenol Degradation
• Electrooxidation
• BDD anode Operating costs

References

1. [1] M. Motamedi, L. Yerushalmi, F. Haghighat, and Z. Chen, “Recent developments in photocatalysis of industrial effluents ։ A review and example of phenolic compounds degradation,” Chemosphere, vol. 296, p. 133688, Jun. 2022, doi: 10.1016/j.chemosphere.2022.133688.
2. [2] M. Barik, C. P. Das, A. Kumar Verma, S. Sahoo, and N. K. Sahoo, “Metabolic profiling of phenol biodegradation by an indigenous Rhodococcus pyridinivorans strain PDB9T N-1 isolated from paper pulp wastewater,” Int Biodeterior Biodegradation, vol. 158, p. 105168, Mar. 2021, doi: 10.1016/j.ibiod.2020.105168.
3. [3] A. Faggiano et al., “Photo-Fenton like process as polishing step of biologically co-treated olive mill wastewater for phenols removal,” Sep Purif Technol, vol. 305, p. 122525, Jan. 2023, doi: 10.1016/j.seppur.2022.122525.
4. [4] S. T. Kadhum, G. Y. Alkindi, and T. M. Albayati, “Determination of chemical oxygen demand for phenolic compounds from oil refinery wastewater implementing different methods,” Desalination Water Treat, vol. 231, pp. 44–53, Aug. 2021, doi: 10.5004/dwt.2021.27443.
5. [5] A. Almasi, M. Mahmoudi, M. Mohammadi, A. Dargahi, and H. Biglari, “Optimizing biological treatment of petroleum industry wastewater in a facultative stabilization pond for simultaneous removal of carbon and phenol,” Toxin Rev, vol. 40, no. 2, pp. 189–197, Apr. 2021, doi: 10.1080/15569543.2019.1573433.
6. [6] C. Iskurt, R. Keyikoglu, M. Kobya, and A. Khataee, “Treatment of coking wastewater by aeration assisted electrochemical oxidation process at controlled and uncontrolled initial pH conditions,” Sep Purif Technol, vol. 248, p. 117043, Oct. 2020, doi: 10.1016/j.seppur.2020.117043.
7. [7] L. Ayed, I. El Ksibi, A. Charef, and R. El Mzoughi, “Hybrid coagulation-flocculation and anaerobic-aerobic biological treatment for industrial textile wastewater: pilot case study,” The Journal of The Textile Institute, vol. 112, no. 2, pp. 200–206, Feb. 2021, doi: 10.1080/00405000.2020.1731273.
8. [8] M. Malakootian and M. R. Heidari, “Removal of phenol from steel wastewater by combined electrocoagulation with photo-Fenton,” Water Science and Technology, vol. 78, no. 6, pp. 1260–1267, Nov. 2018, doi: 10.2166/wst.2018.376.

9. [9] W. Ma et al., “Enhanced degradation of phenolic compounds in coal gasification wastewater by a novel integration of micro-electrolysis with biological reactor (MEBR) under the micro-oxygen condition,” Bioresour Technol, vol. 251, pp. 303–310, Mar. 2018, doi: 10.1016/j.biortech.2017.12.042.
10. [10] N. A. Akhtar, K. K. Kyzy, M. Kobya, and E. Gengec, “Operating cost and treatment analysis of cattle slaughterhouse wastewater by coagulation-flocculation and electrooxidation processes,” Clean Technol Environ Policy, Dec. 2024, doi: 10.1007/s10098-024-03084-7.
11. [11] L. Zhao et al., “Biochar as simultaneous shelter, adsorbent, pH buffer, and substrate of Pseudomonas citronellolis to promote biodegradation of high concentrations of phenol in wastewater,” Water Res, vol. 172, p. 115494, Apr. 2020, doi: 10.1016/j.watres.2020.115494.
12. [12] USEPA, U.S. Environmental Protection Agency (EPA). Water Quality Standards Handbook. Washington, DC: EPA Office of Water, Office of Science and Technology, 2024.
13. [13] M. Y. Abduh, D. Nofitasari, A. Rahmawati, A. Y. Eryanti, and M. Rosmiati, “Effects of brewing conditions on total phenolic content, antioxidant activity and sensory properties of cascara,” Food Chemistry Advances, vol. 2, p. 100183, Oct. 2023, doi: 10.1016/j.focha.2023.100183.
14. [14] M. Besharati Vineh, A. A. Saboury, A. A. Poostchi, A. M. Rashidi, and K. Parivar, “Stability and activity improvement of horseradish peroxidase by covalent immobilization on functionalized reduced graphene oxide and biodegradation of high phenol concentration,” Int J Biol Macromol, vol. 106, pp. 1314–1322, Jan. 2018, doi: 10.1016/j.ijbiomac.2017.08.133.
15. [15] K. Grace Pavithra, P. Sundar Rajan, J. Arun, K. Brindhadevi, Q. Hoang Le, and A. Pugazhendhi, “A review on recent advancements in extraction, removal and recovery of phenols from phenolic wastewater: Challenges and future outlook,” Environ Res, vol. 237, p. 117005, Nov. 2023, doi: 10.1016/j.envres.2023.117005.
16. [16] P. Bhatt et al., “Nanobioremediation: A sustainable approach for the removal of toxic pollutants from the environment,” J Hazard Mater, vol. 427, p. 128033, Apr. 2022, doi: 10.1016/j.jhazmat.2021.128033.
17. [17] N. Panigrahy, A. Priyadarshini, M. M. Sahoo, A. K. Verma, A. Daverey, and N. K. Sahoo, “A comprehensive review on eco-toxicity and biodegradation of phenolics: Recent progress and future outlook,” Environ Technol Innov, vol. 27, p. 102423, Aug. 2022, doi: 10.1016/j.eti.2022.102423.
18. [18] R. Tundis, C. Conidi, M. R. Loizzo, V. Sicari, R. Romeo, and A. Cassano, “Concentration of Bioactive Phenolic Compounds in Olive Mill Wastewater by Direct Contact Membrane Distillation,” Molecules, vol. 26, no. 6, p. 1808, Mar. 2021, doi: 10.3390/molecules26061808.
19. [19] M. Jain et al., “Modelling and statistical interpretation of phenol adsorption behaviour of 3-Dimensional hybrid aerogel of waste-derived carbon nanotubes and graphene oxide,” Chemical Engineering Journal, vol. 490, p. 151351, Jun. 2024, doi: 10.1016/j.cej.2024.151351.
20. [20] Y. Dehmani et al., “Adsorption removal of phenol by oak wood charcoal activated carbon,” Biomass Convers Biorefin, vol. 14, no. 6, pp. 8015–8027, Mar. 2024, doi: 10.1007/s13399-022-03036-5.
21. [21] J. Sun et al., “Oxidative degradation of phenols and substituted phenols in the water and atmosphere: a review,” Adv Compos Hybrid Mater, vol. 5, no. 2, pp. 627–640, Jun. 2022, doi: 10.1007/s42114-022-00435-0.
22. [22] L. Y. Jun et al., “An overview of immobilized enzyme technologies for dye and phenolic removal from wastewater,” J Environ Chem Eng, vol. 7, no. 2, p. 102961, Apr. 2019, doi: 10.1016/j.jece.2019.102961.
23. [23] M. Ağtaş, T. Ormancı-Acar, B. Keskin, T. Türken, and İ. Koyuncu, “Nanofiltration membranes for salt and dye filtration: effect of membrane properties on performances,” Water Science and Technology, vol. 83, no. 9, pp. 2146–2159, May 2021, doi: 10.2166/wst.2021.125.
24. [24] Y.-F. Mi, G. Xu, Y.-S. Guo, B. Wu, and Q.-F. An, “Development of antifouling nanofiltration membrane with zwitterionic functionalized monomer for efficient dye/salt selective separation,” J Memb Sci, vol. 601, p. 117795, Mar. 2020, doi: 10.1016/j.memsci.2019.117795.
25. [25] T. Đuričić, H. Prosen, A. Kravos, S. Mićin, G. Kalčíková, and B. N. Malinović, “Electrooxidation of Phenol on Boron-doped Diamond and Mixed-metal Oxide Anodes: Process Evaluation, Transformation By- products, and Ecotoxicity,” J Electrochem Soc, vol. 170, no. 2, p. 023503, Feb. 2023, doi: 10.1149/1945- 7111/acb84b.
26. [26] X. Zhang et al., “Degradation of phenol by metal-free electro-fenton using a carbonyl-modified activated carbon cathode: Promoting simultaneous H2O2 generation and activation,” Environ Res, vol. 263, p. 120020, Dec. 2024, doi: 10.1016/j.envres.2024.120020.
27. [27] G. Yadav and Md. Ahmaruzzaman, “New generation advanced nanomaterials for photocatalytic abatement of phenolic compounds,” Chemosphere, vol. 304, p. 135297, Oct. 2022, doi: 10.1016/j.chemosphere.2022.135297.
28. [28] K. A. Mohamad Said, A. F. Ismail, Z. Abdul Karim, M. S. Abdullah, and A. Hafeez, “A review of technologies for the phenolic compounds recovery and phenol removal from wastewater,” Process Safety and Environmental Protection, vol. 151, pp. 257–289, Jul. 2021, doi: 10.1016/j.psep.2021.05.015.
29. [29] J. Tao et al., “Multi-step separation of different chemical groups from the heavy fraction in biomass fast pyrolysis oil,” Fuel Processing Technology, vol. 202, p. 106366, Jun. 2020, doi: 10.1016/j.fuproc.2020.106366.
30. [30] W. Raza, J. Lee, N. Raza, Y. Luo, K.-H. Kim, and J. Yang, “Removal of phenolic compounds from industrial waste water based on membrane-based technologies,” Journal of Industrial and Engineering Chemistry, vol. 71, pp. 1–18, Mar. 2019, doi: 10.1016/j.jiec.2018.11.024.
31. [31] N. A. Akhtar and M. Kobya, “Treatment of cattle slaughterhouse wastewater by sequential coagulation- flocculation/electrooxidation process,” MANAS Journal of Engineering, vol. 12, no. 1, pp. 116–128, Jun. 2024, doi: 10.51354/mjen.1407291.
32. [32] A. Turan, R. Keyikoglu, M. Kobya, and A. Khataee, “Degradation of thiocyanate by electrochemical oxidation process in coke oven wastewater: Role of operative parameters and mechanistic study,” Chemosphere, vol. 255, p. 127014, Sep. 2020, doi: 10.1016/j.chemosphere.2020.127014.
33. [33] O. T. Can, E. Gengec, and M. Kobya, “TOC and COD removal from instant coffee and coffee products production wastewater by chemical coagulation assisted electrooxidation,” Journal of Water Process Engineering, vol. 28, pp. 28–35, Apr. 2019, doi: 10.1016/j.jwpe.2019.01.002.
34. [34] Z. Movaffagh, A. Khataee, A. Jamal Sisi, Z. Jalali, M. Zarei, and M. Kobya, “Mixed metal oxide (Ru, Ir, Sn) electrodes in the anodic activation of peroxydisulfate for a sustainable degradation of rifampicin,” Journal of Industrial and Engineering Chemistry, vol. 138, pp. 575–585, Oct. 2024, doi: 10.1016/j.jiec.2024.04.035.
35. [35] M. Moradi, Y. Vasseghian, A. Khataee, M. Kobya, H. Arabzade, and E.-N. Dragoi, “Service life and stability of electrodes applied in electrochemical advanced oxidation processes: A comprehensive review,” Journal of Industrial and Engineering Chemistry, vol. 87, pp. 18–39, Jul. 2020, doi: 10.1016/j.jiec.2020.03.038.
36. [36] Z. Ukundimana, P. I. Omwene, E. Gengec, O. T. Can, and M. Kobya, “Electrooxidation as post treatment of ultrafiltration effluent in a landfill leachate MBR treatment plant: Effects of BDD, Pt and DSA anode types,” Electrochim Acta, vol. 286, pp. 252–263, Oct. 2018, doi: 10.1016/j.electacta.2018.08.019.
37. [37] N. A. Akhtar, E. Gengec, and M. Kobya, “Treatment of Slaughterhouse Plant Wastewater by Sequential Chemical Coagulation-Continuous Flow Electrooxidation Process,” J Electrochem Soc, vol. 171, no. 7, p. 073505, Jul. 2024, doi: 10.1149/1945-7111/ad6192.
38. [38] APHA, Standard Methods for the Examination of Water and Wastewater, 24th ed. Washington DC: American Public Health Association, American Water Works Association, Water Environment Federation., 2023.
39. [39] N. Akhtar and M. Kobya, “Efficient degradation of industrial slaughterhouse wastewater by electrooxidation process: impact of DSA anode materials on oxidation and operating costs,” Environ Technol, Mar. 2025.
40. [40] D. Amado-Piña et al., “Synergic effect of ozonation and electrochemical methods on oxidation and toxicity reduction: Phenol degradation,” Fuel, vol. 198, pp. 82–90, Jun. 2017, doi: 10.1016/j.fuel.2016.10.117.
41. [41] Y. Gong et al., “Novel graphite-based boron-doped diamond coated electrodes with refractory metal interlayer for high-efficient electrochemical oxidation degradation of phenol,” Sep Purif Technol, vol. 355, p. 129550, Mar. 2025, doi: 10.1016/j.seppur.2024.129550.
42. [42] Y. Zhu, H. Wang, Q. Jiang, A. T. Kuvarega, and J. Li, “Hexagonal boron nitride-doped carbon membrane as anode for the enhanced adsorption and electrochemical oxidation of phenol,” J Environ Chem Eng, vol. 12, no. 3, p. 113002, Jun. 2024, doi: 10.1016/j.jece.2024.113002.
43. [43] N. A. Akhtar, M. Kobya, and A. Khataee, “Removal of Cr(Ⅵ) by continuous flow electrocoagulation reactor at controlled and uncontrolled initial pH conditions,” Chemical Engineering Research and Design, vol. 214, pp. 403–414, Feb. 2025, doi: 10.1016/j.cherd.2025.01.015.
44. [44] B. G. Savić et al., “Electrochemical oxidation of a complex mixture of phenolic compounds in the base media using PbO2-GNRs anodes,” Appl Surf Sci, vol. 529, p. 147120, Nov. 2020, doi: 10.1016/j.apsusc.2020.147120.
45. [45] E. M. S. Oliveira et al., “Performance of (in)active anodic materials for the electrooxidation of phenolic wastewaters from cashew-nut processing industry,” Chemosphere, vol. 201, pp. 740–748, Jun. 2018, doi: 10.1016/j.chemosphere.2018.02.037.
46. [46] X. Liu, S. You, F. Ma, and H. Zhou, “Characterization of electrode fouling during electrochemical oxidation of phenolic pollutant,” Front Environ Sci Eng, vol. 15, no. 4, p. 53, Aug. 2021, doi: 10.1007/s11783-020- 1345-7.
47. [47] P. Alfonso-Muniozguren, S. Cotillas, R. A. R. Boaventura, F. C. Moreira, J. Lee, and V. J. P. Vilar, “Single and combined electrochemical oxidation driven processes for the treatment of slaughterhouse wastewater,” J Clean Prod, vol. 270, p. 121858, Oct. 2020, doi: 10.1016/j.jclepro.2020.121858.
48. [48] N. D. Mu’azu, M. Al-Yahya, A. M. Al-Haj-Ali, and I. M. Abdel-Magid, “Specific energy consumption reduction during pulsed electrochemical oxidation of phenol using graphite electrodes,” J Environ Chem Eng, vol. 4, no. 2, pp. 2477–2486, Jun. 2016, doi: 10.1016/j.jece.2016.04.026.
49. [49] E. Gengec, “Treatment of highly toxic cardboard plant wastewater by a combination of electrocoagulation and electrooxidation processes,” Ecotoxicol Environ Saf, vol. 145, pp. 184–192, Nov. 2017, doi: 10.1016/j.ecoenv.2017.07.032.
50. [50] A. S. Fajardo et al., “Electrochemical oxidation of phenolic wastewaters using a batch-stirred reactor with NaCl electrolyte and Ti/RuO2 anodes,” Journal of Electroanalytical Chemistry, vol. 785, pp. 180– 189, Jan. 2017, doi: 10.1016/j.jelechem.2016.12.033.
51. [51] T. Đuričić, H. Prosen, A. Kravos, S. Mićin, G. Kalčíková, and B. N. Malinović, “Electrooxidation of Phenol on Boron-doped Diamond and Mixed-metal Oxide Anodes: Process Evaluation, Transformation By-products, and Ecotoxicity,” J Electrochem Soc, vol. 170, no. 2, p. 023503, Feb. 2023, doi: 10.1149/1945-7111/acb84b.
52. [52] J. Zambrano and B. Min, “Comparison on efficiency of electrochemical phenol oxidation in two different supporting electrolytes (NaCl and Na2SO4) using Pt/Ti electrode,” Environ Technol Innov, vol. 15, p. 100382, Aug. 2019, doi: 10.1016/j.eti.2019.100382.
53. [53] D. Gümüş and F. Akbal, “Comparison of Fenton and electro-Fenton processes for oxidation of phenol,” Process Safety and Environmental Protection, vol. 103, pp. 252–258, Sep. 2016, doi: 10.1016/j.psep.2016.07.008.
54. [54] D. Amado-Piña et al., “Synergic effect of ozonation and electrochemical methods on oxidation and toxicity reduction: Phenol degradation,” Fuel, vol. 198, pp. 82–90, Jun. 2017, doi: 10.1016/j.fuel.2016.10.117.
55. [55] M. Radwan, M. Gar Alalm, and H. Eletriby, “Optimization and modeling of electro-Fenton process for treatment of phenolic wastewater using nickel and sacrificial stainless steel anodes,” Journal of Water Process Engineering, vol. 22, pp. 155–162, Apr. 2018, doi: 10.1016/j.jwpe.2018.02.003.
56. [56] N. D. Mu’azu, M. Al-Yahya, A. M. Al-Haj-Ali, and I. M. Abdel-Magid, “Specific energy consumption reduction during pulsed electrochemical oxidation of phenol using graphite electrodes,” J Environ Chem Eng, vol. 4, no. 2, pp. 2477–2486, Jun. 2016, doi: 10.1016/j.jece.2016.04.026.
57. [57] A. S. Fajardo et al., “Electrochemical oxidation of phenolic wastewaters using a batch-stirred reactor with NaCl electrolyte and Ti/RuO2 anodes,” Journal of Electroanalytical Chemistry, vol. 785, pp. 180– 189, Jan. 2017, doi: 10.1016/j.jelechem.2016.12.033.
58. [58] J. Zambrano, H. Park, and B. Min, “Enhancing electrochemical degradation of phenol at optimum pH condition with a Pt/Ti anode electrode,” Environ Technol, vol. 41, no. 24, pp. 3248–3259, Oct. 2020, doi: 10.1080/09593330.2019.1649468.