Electrochemical Treatment of Electroplating Wastewater Using Ti/TiO₂-GO-SnO₂NTs Electrode: Optimization and Performance Evaluation in Batch and Continuous Modes

The release of hazardous chemicals has made recalcitrant compounds a critical issue in water pollution. Electroplating industry wastewater contains toxic heavy metals, organic solvents, and complex effluents, posing significant environmental and health risks. Water contaminated with heavy metal ions poses significant threats to human health and the environment. Due to its greater efficiency, electrochemical oxidation (EO) is frequently used and offers several advantages over conventional methods. The present research explores the EO method for removing zinc (Zn), nickel (Ni), and chemical oxygen demand (COD) from electroplating wastewater (EWW) using a synthesized Ti/TiO 2 -GO-SnO 2 NTs electrode, prepared through a anodization method. This study optimized batch and once-through continuous mode experiments using a Box-Behnken design under the response surface methodology. The effect of input parameters (i.e., time (t = 30–120 min), current density (j = 6.7–33.44 mA cm −2 ), and pH (3–9)) on % removal and energy consumption were examined. Under the optimized conditions, % Zn, % Ni, % COD removal, and energy consumption efficiency were determined to be 95.02%, 93.61%, 91.14%, and 2.1 kWhm −3 , respectively. The contribution of several reactive oxidizing species to the EO was examined in the presence of scavengers. This study demonstrates that synthesized electrodes combined with EO offer an effective technology for removing electroplating compounds.