Dye Manufacturing Wastewater Treatment by Adsorption and Fenton Processes: Performance Evaluation and Cost Analysis

The dye manufacturing industry generates substantial volumes of wastewater that contains color, metals, and various toxic chemicals depending on the specific dyes produced. Effective treatment of this complex wastewater is of great importance to ensure compliance with discharge regulations and protect aquatic ecosystems. In this study, the treatability of wastewater samples taken from the dye manufacturing industry at two different times was investigated using adsorption and Fenton oxidation processes. Treatment performance and cost-effectiveness were assessed by using different pH values and activated carbon dosages in the adsorption process, and different Fe²⁺ and H₂O₂ dosages in the Fenton process. The optimum removal of chemical oxygen demand (COD) and color in the adsorption process was achieved at pH 5, and at 20 g L⁻¹ activated carbon, COD and color removal were achieved at above 64.2% and 95%, respectively. In Fenton oxidation studies, a COD removal rate of 56.6% was achieved for wastewater 1 at 3000 mg L⁻¹ Fe²⁺ and 6000 mg L⁻¹ H₂O₂. Similarly, a 60.3% COD removal rate was achieved at 4000 mg L⁻¹ Fe²⁺ and 6000 mg L⁻¹ H₂O₂ in wastewater 2. In the Fenton process, the color removal rate for both wastewaters approached approximately 98%–99%. The cost of wastewater treatment for dye manufacturing wastewater was calculated to be $10.58–15.53 m⁻³ in the adsorption process and $20.57–22.89 m⁻³ in the Fenton oxidation process. Overall, the findings indicate that both adsorption and Fenton processes are effective treatment alternatives for dye manufacturing wastewater, providing significant reductions in COD and color.