Treatment of real confectionery wastewater by electrocoagulation and electrochemical peroxidation: A comparative assessment

• Due to their technical similarities, EC and ECP were compared for treating real confectionery wastewater. • Both processes achieved similar COD removal (∼56%). • EC offered fast turbidity removal (88.8%) and the lowest operating cost (US $1.83 m⁻³). • ECP delivered the highest turbidity removal (98.7%) and improved biodegradability. • EC and ECP are competitive alternatives compared to other treatment technologies. The confectionery industry generates significant volumes of wastewater containing fats, oils, sugars, flavorings, and colorants, which present environmental challenges. This study presents a comprehensive comparative evaluation of two easy-to-implement electrochemical processes—electrocoagulation (EC) and electrochemical peroxidation (ECP)—for the treatment of real confectionery wastewater. The results show that, despite being fundamentally different processes—separation in the case of EC and advanced oxidation in the case of ECP—both achieved similar COD removal efficiencies: 55.67 ± 2.06% (3511.00 ± 130.10 mg L⁻¹) for EC after 15 min of electrolysis at 30 mA cm⁻² using an Al anode, and 57.56 ± 5.92% (2603.96 ± 267.71 mg L⁻¹) for ECP at 20 mA cm⁻², 440 mg L⁻¹ H₂O₂, and pH = 3 in 60 min. The main difference lies in the fate of the organic matter during each treatment. Turbidity removal reached 88.81 ± 0.31% (724.98 FAU) for EC and 98.74 ± 0.16% (625.35 FAU) for ECP, while operational costs were estimated at US $1.83 m⁻³ for EC and US $12.25 m⁻³ for ECP. Although several studies have explored the potential of EC and ECP individually, no detailed comparative assessment of these fundamentally different yet technically similar processes has been reported to date. The technical evaluation presented here indicates that EC is more suitable for large-scale and pre-treatment applications due to its simplicity, low operational costs and short reaction time, while ECP holds promise for enhancing biodegradability in integrated treatment systems. Although this study focuses on wastewater from the confectionery industry, the comprehensive comparative evaluation presented may serve as a useful reference for treating other types of industrial wastewater. This could support the broader application of these technically viable and sustainable technologies.