Optimization of azithromycin degradation by Fenton oxidation: a comparative study of general full factorial design 33 and Box-Behnken design

In this study, the degradation of Azithromycin (AZM) by Fenton oxidation process (H2O2/Fe2+) was examined. The experiments were carried out in a batch reactor at ambient temperature and the efficiency of this treatment was monitored by analysing the overall parameter chemical oxygen demand (COD). Efficacy of Fenton’s reagent for AZM degradation was studied concerning the process variables including (A) pH, (B) [H2O2]/[AZM], and (C) [H2O2]/[Fe2+]. The effect of these process variables and the interaction amongst each other was studied by a general full factorial design (GFFD) (3-level 3-factor) and response surface methodology, Box-Behnken design (BBD) was used to optimize this process. Additionally, a comparative analysis was conducted to assess the effectiveness of the GFFD and BBD methods in predicting COD removal. According to results of the analysis of variance ANOVA for COD removal efficiency by GFFD model, the model is suggested to be significant by the model F-value of 4.69. The accepted model was fit with an R-square of 0.91, in order to simulate the reaction over the selected ranges of the process variables, a BBD model was obtained, model statistics showed that a significant model was obtained, with an F-value of 64.82 for the corresponding probability of < 0.0005. The accepted model was fit with an R-square of 0.9942 and an adjusted R-square of 0.9798. Based on the optimized of the two models, the ideal process conditions were determined as pH = 2.5, [H2O2]/[AZM] = 145, and [H2O2]/[Fe2+] = 8., during a 90 min reaction time, the COD elimination rate is 94.13%. The results obtained from this study offer valuable insights for optimizing the Fenton process and achieving efficient degradation of AZM, thereby contributing to the field of wastewater treatment and environmental remediation.