APPLICATION OF THE ELECTRO-FENTON METHOD FOR THE DEGRADATION OF ORGANIC DYES IN TANNERY EFFLUENTS

• DOI: https://doi.org/10.22533/at.ed.1317642627039

• Palavras-chave: Electro-Fenton. Tannery effluents. Synthetic dyes. POA.

• Keywords: Electro-Fenton. Tannery effluents. Synthetic dyes. POA.

• Abstract:

  Faced with the growing problem of the improper disposal of millions of liters of wastewater containing toxic compounds such as synthetic dyes used in industrial processes for leather dyeing, there is a need for effective and sustainable treatment methods (Kamenická; Kuchtová, 2024). These dyes pose a serious threat to the environment and human health, potentially causing eutrophication and having carcinogenic effects when they come into contact with water resources used for public supply (Sobczak; Bujnowicz; Bilińska, 2024).
  Although techniques such as chlorination, coagulation, and the use of membranes have been employed with moderate results, the Advanced Oxidation Processes (AOP) approach has been gaining prominence due to its ability to degrade the chemical structure of contaminants through the generation of reactive oxygen species (Li et al., 2025).
  Recent literature highlights that the Electro-Fenton POA stands out for its in situ generation of hydrogen peroxide and hydroxyl radicals (•OH), which are capable of oxidizing recalcitrant organic compounds. Furthermore, its efficiency depends directly on parameters such as pH, electrode material, oxygen availability, electrolyte concentration, iron concentration, and current density (Yin et al., 2025).
  In line with the Electro-Fenton process, Chen et al. (2024) state that carbon is an effective redox mediator in the reduction of azo dyes due to its high electron-conducting capacity. Zhao et al. (2024) also demonstrated the effectiveness of the Electro-Fenton system coupled with a packed bed of activated carbon and resins, achieving a degradation rate of up to 98% for the dyes. Furthermore, Sahu and Poler (2024) emphasize that dyes are major organic contaminants due to their high toxicity, and AERs offer a viable solution through the electrogeneration of •OH radicals, which promote the decolorization and degradation of remaining compounds (Razzaq et al., 2024).
  For this reason, the best way to utilize this wastewater is through reuse, especially in industry, where the need for efficient and economically viable treatments is significant. Although there are many methods for water treatment, most are costly and have limited efficiency (Olvera-Vargas et al., 2024; Sobczak; Bujnowicz; Bilińska, 2024).