Optimization of the acetaminophen degradation from polluted water using the photoelectro‐Fenton method

Abstract The increasing production and consumption of medicinal substances and the presence of their residues in the environment have created potential dangers. Therefore, finding ways to reduce the environmental risks of pharmaceutical residues is one of the challenges facing researchers. Acetaminophen (ACE) is a widely utilized pharmaceutical worldwide, and its presence in the environment is concerning due to potential adverse effects. In this study, the efficiency of the photoelectro‐Fenton method for the ACE removal was evaluated. In the photoelectro‐Fenton method, a stainless steel plate was used as the cathode and a titanium plate as the anode. Lamps emitting wavelengths of 400 nm were used as UV light sources. In this method, at the first step, the effect of operating variables, including initial ACE concentration (10–120 mgL −1 ), initial H 2 O 2 volume (20–110 μL), pH (2–6) of the sample, and reaction time (20–50 min) was investigated by using response surface methodology (RSM). In the next step, in order to obtain optimal points, the mathematical model obtained with the two methods of desirability function (DF) and gray wolf meta‐heuristic algorithm was examined, and the results showed that the desirability function (with 91.0%) was more efficient than the gray wolf method (with 76.8). Based on these calculations and the desirability score of 1, the removal of ACE was optimized at 91.0% with the optimum values of the variables that were set as initial concentration of ACE 20.0 mg L −1 , H 2 O 2 value equal to 45.0 μL, pH = 3.0, and reaction time of 45.0 min.