Preparation of powerful exchanged Faujasite zeolite materials used as effective heterogeneous catalyst for photo-Fenton oxidation of methyl orange (MO)

Novel heterogeneous photo-Fenton catalyst, iron coated Faujasite zeolite (Fe-FAU) was synthesized by exchange-calcination method. Iron was exchanged in zeolite support based on Faujasite type zeolites prepared in laboratory from instratified illitic-kaolinite raw Tunisian clay. The studied materials were characterized by XRD, BET, SEM–EDX and FTIR methods. X-ray diffraction (XRD) analysis showed that the zeolite structure was not affected by the catalyst preparation method. BET results revealed that Fe-FAU possess a trimodal structure (micro, meso and macropores) with a porosity of 0.28 cm3/g. The catalytic performance of the Fe-FAU was studied for the oxidation of methyl orange (MO) in aqueous solution in the presence of hydrogen peroxide. The effects of different operating parameters on the degradation efficiency were studied at atmospheric pressure. The results indicated that the Fe doped zeolite exhibited good degradation efficiency. Measurements of the mineralization of MO by TOC analysis showed that the maximum degradation of MO (94%) was detected with 50 mg of adsorbent dosage after 20 min of contact time and under UVC irradiation. Moreover, in order to predict the empirical variables significance, the variances analysis “ANOVA” was used. Response Surface Methodology (RSM) incorporating Central Composite Design (CCD) of experiments was applied to optimize oxidation parameters. High regression (R2 = 0.95) and the low probability (p value < 0.0001) values signify the validity of the quadratic model to predict the removal (%) of MO.