Ionic liquid-assisted sol-gel synthesis of Fe2O3-TiO2 for enhanced photocatalytic degradation of bisphenol a under UV illumination: Modeling and optimization using response surface methodology

Abstract This study was undertaken to synthesize Fe2O3-doped TiO2 nanoparticles using a long tail ionic liquid-assisted sol-gel method (IL-Fe2O3/TiO2) in order to photodegrade bisphenol A (BPA). Physicochemical properties of the synthesized photocatalysis were characterized through FTIR, FESEM-EDX, XRD, and DRS. The modeling and optimization of the photodegradation of BPA by IL/ Fe2O3-TiO2 were conducted with response surface methodology (RSM) by considering the central composite design (CCD). The results revealed that the 1-octadecyl-3-methylimidazolium bromide ([OMD]Br) ionic liquid, in combination with ferric oxide dopant, created low aggregated nanocomposites with a uniform and tiny grain size. 2.4 eV. bandgap energy was computed for IL-Fe2O3/TiO2. The quadratic model obtained from the ANOVA results of photodegradation processes. A BPA removal efficiency of 90.33 % was acquired under optimal conditions (IL-Fe2O3/TiO2 loading dose = 0.75 g/L, pH = 9, initial BPA concentration = 10 mg/L, and UV irradiation time = 97.5 min). The results indicated that the photodegradation of BPA was mostly affected by the variables of time, pH, and initial BPA concentration, respectively. Only the second term of the IL-Fe2O3/TiO2 loading dose as a variable had a significant effect on the efficiency of the process. The Langmuir–Hinshelwood model was selected to investigate photodegradation kinetics.