Graphite‐Based Electrochemical Degradation of Congo Red in Aqueous Media: An Eco‐Sustainable Approach for Treatment of Residual Dye in Wastewater

ABSTRACT The present study investigates the decolorization of aqueous solution of Congo red across the concentration range (0.5, 1, 2, 5, and 10 ppm) using an electrochemical oxidation process employing graphite electrodes as both anode and cathode. Rapid and nondestructive quantification of selected dye was achieved using double beam UV–Vis spectroscopy by monitoring its UV–visible absorption profile. Response surface methodology (RSM) was used as statistical tool for optimization of initial concentration, applied voltage and operating time. Applied central composite design (CCD) in RSM and resulting quadratic polynomial model exhibited sufficient accuracy to serve as predictive equation in the studied domain. Results indicated that the highest removal efficiency for Congo red was 98.4% for 0.5 ppm at operational time of 40 min for 20 V with current density of 2.1 mA cm −2 . Thus, the present study proposes an environmentally sustainable, rapid, and cost‐effective approach for remediation of dilute residual dye streams rather than bulk treatment of dye‐enriched wastewater, exhibiting enhanced economic feasibility compared to existing studies by achieving high removal efficiency at reduced energy consumption.