Box–Behnken Design for the Optimization of Fenton Degradation of Paracetamol in Aqueous Solution

Abstract

The present work focuses on the treatment of model wastewater that simulates industrial pharmaceutical effluent. Paracetamol (PCT) is the most widely consumed medicine, particularly during the fight against the Corona virus disease-2019 (COVID-19) pandemic and is therefore one of the most persistent contaminants in aquatic ecosystems. In this study, the degradation of PCT was investigated using the conventional homogeneous Fenton reaction (H₂O₂/Fe²⁺) in a batch reactor operating at an ambient temperature with a degradation time of 60 min. The effectiveness of the treatment was assessed by monitoring the removal of total organic carbon (TOC). The study investigated the effect of the key process variables: A: pH, B: [H₂O₂]/[PCT], and C: [H₂O₂]/[Fe²⁺]. The influence of these variables was systematically examined utilizing a Box−Behnken design (BBD) with a 3-level 3-factor configuration and response surface methodology. The analysis of variance (ANOVA) for TOC removal efficiency by BBD model shows that the model is significant. The model F-value is 41.71 and the p-value is 0.0004. The model was fit with an R² of 0.9869 and an adjusted R² of 0.9632. The ideal process conditions were determined as pH = 3, [H₂O₂]/[PCT] = 15, [H₂O₂]/[Fe²⁺] = 16, with a TOC elimination rate of 33.40%. The results show how to make the Fenton process work better and how to get rid of PCT more efficiently. This research could lead to new ways to treat wastewater and clean up the environment.