Optimization of electro-Fenton/BDD process for decolorization of a model azo dye wastewater by means of response surface methodology

• Published in: Desalination Vol. 286; pp. 63 - 68
• Main Authors: Cruz-González, Karla, Torres-Lopez, Omar, García-León, Azucena M., Brillas, Enric, Hernández-Ramírez, Aracely, Peralta-Hernández, Juan M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2012; Elsevier
• Subjects: Applied sciences; azo dyes; BDD; boron; decolorization; desalination; Electro-Fenton; electrochemistry; electrodes; electrolysis; Exact sciences and technology; General purification processes; Pollution; Response surface methodology; Textile azo dye; wastewater; Wastewater treatment; Wastewaters; Water treatment and pollution; Electro-Fenton; BDD; Response surface methodology; Textile azo dye; Wastewater treatment; Discoloration; Hydrogen peroxide; HPLC chromatography; Density; Modeling; Optimization; Operating conditions; Waste water; Electrodes; Ultraviolet radiation; Electrolysis; Azo dye; Production; Fenton reaction; Waste water purification; Factorial design; Textile industry
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2011.11.005

This work discusses the decolorization and degradation of textile azo dye solutions containing Acid Yellow 36 (AY-36) by the electro-Fenton process (EF) using an undivided electrochemical cell containing a boron doped diamond (BDD) electrode as cathode for H 2O 2 production. The independent parameters of current density, dye concentration, Fe 2 + concentration and electrolysis time in the range of 8–23 mA/cm 2, 60–80 mg/L, 0.1–0.3 mM and 10–50 min, respectively, were evaluated. Experimental data were optimized by means of a 2 4 factorial design and Response Surface Methodology (RSM). These results revealed that the optimal operating conditions to achieve 95.9% efficiency for dye decolorization with complete degradation were current density = 15 mA/cm 2, AY-36 concentration = 80 mg/L, Fe 2 + content = 0.3 mM and electrolysis time = 50 min. This was confirmed with UV–vis and HPLC assessments during the EF/BDD treatment. ► Hydrogen peroxide was electrogenerated at BDD cathode. ► The dye Acid Yellow 36 was decolorized by electro-Fenton process. ► Decolorization depended on current density, dye and Fe2 + contents and electrolysis time. ► These variable parameters were optimized by response surface methodology.