<p>This study investigates the efficiency and optimization of petroleum wastewater treatment using the electrocoagulation (EC) process with recycled aluminum from beverage cans as electrodes, providing an eco-friendly and circular-economy solution. The experimental study focused on evaluating the effects of initial pH (4–10), current density (4–30 mA/cm²), inter-electrode distance (1–5 cm), and active electrode area (65.66–115.16 cm²) on the removal efficiency of pollutants. For the modeling phase, three key operational parameters treatment time (30–60 min), current density (4–30 mA/cm²), and inter-electrode distance (1–5 cm) were analyzed using Response Surface Methodology (RSM) based on a Box–Behnken design. Pareto graphical analysis revealed that current density was the most influential factor, followed by treatment time and inter-electrode distance. The developed quadratic models were statistically significant (p &lt; 0.05) and showed excellent agreement between experimental and predicted results. The optimal conditions (treatment time = 45.15 min, current density = 30 mA/cm², inter-electrode distance = 2.66 cm) yielded complete removal efficiencies for turbidity and TSS, and 99.6% for COD. Under these conditions, COD, BOD₅, TSS, and oil &amp; grease concentrations were drastically reduced to 3, 1.2, 1.1, and 2 mg/L, while heavy metals (Pb, Cr³⁺, Cr⁶⁺) were removed to environmentally acceptable levels. The average specific energy consumption under the optimized operational conditions was found to be 1.76 kWh/m³, confirming the energy efficiency of the process. Overall, the results confirm that using recycled aluminum electrodes significantly enhances both performance and sustainability. The combination of RSM optimization and Pareto analysis demonstrates that electrocoagulation using recycled aluminum electrodes is a robust, energy-efficient, and environmentally sustainable technique for petroleum wastewater treatment, in alignment with circular economy principle.</p>