Electro-Fenton method for dye removal of agro-industrial wastewater from flower production

Abstract

Removal of recalcitrant dyes from agroindustrial wastewater produced in flower processes represents a significant environmental challenge for flower industries worldwide. Advanced oxidation processes (AOPs) emerge as a clean and effective costly alternative for removing dye contaminants in wastewater. This study used an electro-Fenton technique as an alternative for the treatment of colored wastewater from flower-producing crops in Colombia. Initially, the physicochemical characterization of the wastewater was carried out by Chemical Oxygen Demand (COD), color, pH, conductivity, temperature, and oxidation-reduction potential. Subsequently, an electrochemical process was carried out through a power source and six iron electrodes. Variables, such as hydrogen peroxide concentration (500 and 700 mg/l H2O2), amperage (1 and 2 A), and treatment time (60 and 90 minutes), were controlled. Based on a desirability function for multiple response analysis, the electro-Fenton process allowed a maximum COD removal of 80.9% and 88.5% for color (desirability criterion of 86%). Residence time in the reactor, voltage, current density, and concentration of hydrogen peroxide were the most significant variables. Finally, the role of other physicochemical variables involved during the dye degradation process was explained.

Keywords

• advanced oxidation processes
• agro-industrial wastewater
• colored water
• electrochemistry
• flower industry
• water pollution
• color removal
• electro fenton