Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 3 4 2017 10 01 Preparation, characterization and photocatalytic degradation of methylene blue by Fe3+ doped TiO2 supported on natural zeolite using response surface methodology 205 216 655 10.22104/aet.2018.2462.1124 EN Hadieh Taghvaei Department of Chemical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran Mehrdad Farhadian Department of Chemical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran Nila Davari Department of Chemical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran Samira Maazi Department of Chemical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran Journal Article 2017 09 11 The photocatalytic degradation of methylene blue was investigated with TiO₂ and Fe₂O₃ nanoparticles supported on natural zeolite. The synthesized photocatalyst was characterized by XRD, XRF, FT-IR, EDX, FE-SEM, and BET analyses. The results of XRD, FT-IR, and EDX confirmed the successful loading of Fe³⁺ doped TiO₂<strong> </strong>nanoparticles on natural zeolite. Further, the FE-SEM results confirmed the deposition of TiO₂/Fe₂O₃ on the zeolite, with the approximate particle size being 52.3 nm. According to the XRF results, the synthesized nanoparticles had Fe³⁺/TiO₂ molar ratios of 0.06 in the synthesized photocatalyst. Based on BET analysis, the surface area of TiO₂/Fe³⁺/natural zeolite was about 112.69 m²/g.  The effects of operational factors such as pH (6-10), dye concentration (25-75 mg/L) and H₂O₂ concentration (10-40 mg/L) were considered and optimized via response surface methodology utilizing Box-Behnken design. The optimization results indicated that the maximum percentage of degradation was achieved at a dye concentration of 25 mg/L, initial pH of 10, and H₂O₂ concentration of 40 mg/L with a 90 min irradiation time and a 1 g/l photocatalyst concentration. The dye degradation efficiency reached 92% under this optimum condition. https://aet.irost.ir/article_655_3d2d8ccb37df977cb6d9da15b76c3f3a.pdf