A Study on Degradation of 1-Ethyl-3-Methylimidazolium Chloride and 1-Butyl-3-Methylimidazolium Chloride by Fenton’s Process and Optimization using Response Surface Methodology

IJEP 42(10): 1225-1233 : Vol. 42 Issue. 10 (October 2022)

Shareefa Nadaf and Prakash Kalburgi*

Basaveshwar Engineering College, Department of Civil Engineering, Bagalkot – 587 102, Karnataka, India


In this study, the process optimization was carried out by the application of response surface methodology (RSM) for the degradation of ionic liquids, namely 1-ethyl-3-methylimidazolium chloride (EMIMCl) and 1-butyl-3-methylimidazolium chloride (BMIMCl) in an aqueous solution using Fenton’s oxidation process. Experiments were designed using central composite design (CCD) of response surface methodology (RSM). The oxidant dosage (H2O2), the dosage of catalyst (Fe+2) and pH were selected as three independent input operating variables. The goodness of fit of the model was measured using the regression coefficient (R2) and the adjusted regression coefficient (R2adj). The R2 values of the model were 0.9564 and 0.9270 for EMIMCl and BMIMCl, respectively whereas the R2adj values were 0.9891 and 0.9817 for EMIMCl and BMIMCl, respectively. These values indicate a good fit for the model. An average maximum TOC degradation of EMIMCl (83.68%) and BMIMCl (73.54%) were calculated. The good agreement between the predicted values and the experimental values confirms the validity of the model for simulating the degradation of EMIMCl and BMIMCl by the Fenton oxidation process.


Imidazolium-based ionic liquids, Degradation, Fenton’s oxidation, Central composite design, Response surface methodology


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