Integrated assessment of electrocoagulation efficiency, energy demand, and toxicity mitigation for Reactive Red BF-4B dye

This study evaluated the efficiency of electrocoagulation (EC) in the removal of Reactive Red BF-4B dye, also considering the energy consumption and residual toxicity of the treated wastewater. Batch reactor experiments were conducted using iron electrodes and different electrolytes, and a Box-Behnken experimental design was applied to investigate the effects of pH, electrical conductivity, and operation time, with statistical significance assessed by ANOVA. Under optimized conditions, EC achieved over 99% color removal, with excellent model fitting (R²=0.970) and minimal pH influence. Kinetic analysis indicated rapid decolorization, while total organic carbon (TOC) and total nitrogen (TN) removal required longer electrolysis times. Energy consumption remained moderate, reflecting a favorable balance between efficiency and operational cost. Bioassays with Artemia salina showed a significant reduction in acute toxicity, with the median lethal concentration (LC₅₀) increasing from approximately 33% to 64% over the course of the treatment. These results demonstrate that electrocoagulation is a promising alternative for textile wastewater treatment, combining high efficiency in dye removal, reduction of organic load, and decreased toxicity, with low environmental impact and relevant for practical application.