AbstractIn this study, Response Surface Methodology (RSM) was employed to optimize the experimental factors influencing the simultaneous removal of NOx and SO2 in a spray tower wet scrubbing experiment. Thermally modified copper slag (CS‐CaO‐900) was prepared by heat treating the original copper slag. The performance of CS‐CaO‐900 in the synchronized removal of NOx and SO2 was then evaluated in an expanded experimental setup. Based on single‐factor experimental results, the Box‐Behnken design of RSM was used to optimize the reaction parameters in a two‐stage sequential reactor (bubbling reactor + spray tower). NOx removal efficiency was modeled as a function of reaction temperature, pH, and H2O2 concentration. Regression curves provided a visual representation of the interaction effects among these parameters on NOx removal efficiency in the thermally modified copper slag/H2O2 composite slurry. This study elucidates the characteristics of each parameter under wet scrubbing conditions and provides essential data for industrial applications.