Effect of Environmental Factors on the Degradation of Organic Dyes by Electro-Fenton Using Carbon Felt Cathode

Abstract

In this study, an electro-Fenton (EF) process using carbon felt (CF) as the cathode and titanium/ platinum (Ti/Pt) as the anode was tested for removing rhodamine B (RhB) and other organic dyes in water. Characterization of the CF material was conducted by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The influence of various environmental factors (i.e. solution pH, current density, catalyst dosage, RhB concentration, and type of dyes and electrolytes) on the dye removal was investigated. The results show that the maximum removal efficiency of RhB was 98% within 15 min at the optimal conditions of 50 mgRhB/L, 0.05 M Na2SO4, pH 3, 0.1 mM Fe2+, and 6.67 mA/cm2. The decomposition of RhB follows a pseudofirst-order model with the decomposition rate constant of 0.256 min–1. Radical quenching experiments show that superoxide plays a key role in RhB degradation. Finally, results show that CF has high stability and degradation efficiency, which is suitable as a cathode for the removal of organic dyes in wastewater.