Characterization and Photo-catalytic Efficiency of MnFe2O4/ Zn2SiO4 for Aniline Degradation Using Box-Behnken Experimental Design and Simulated Solar Radiation

In this research, Zn2SiO4 as a support and MnFe2O4 as a main photo-catalyst were individually synthesized and MnFe2O4 was fixed on Zn2SiO4 with solid state dispersion method. MnFe2O4 nano photo-catalyst was synthesized by co-precipitation method and reflux condition for 12 hours at 85°C in the presence of urea. For identification of catalysts Fourier-transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDXS), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and Brunauer-Emmett-Teller (BET) techniques were used. The size of MnFe2O4 was determined about 15 nm after the fixation on the Zn2SiO4. The photo-catalytic efficiency of MnFe2O4/Zn2SiO4 was checked for degradation of aniline aqueous solution utilizing the irradiation of a 1 kW Xe lamp fitted with the AM1.5 filter (to simulate the solar light spectrum) in the presence of H2O2. Degradation process was modeled and optimized successfully applying response surface methodology (RSM) according to Box-Behnken designs. Experiment results were showed that initial concentration of aniline=5.5 ppm, H2O2 initial concentration=5.3 mM, pH=11 and nano photo-catalyst amount =0.4 g/L are optimal conditions and the degradation efficiency in this condition achieved is 96%. In the optimum conditions, arrangement of (MnFe2O4/Zn2SiO4)> (MnFe2O4)> (Zn2SiO4) was obtained for efficiency of photo-catalytic degradation of aniline in aqueous solution. Decomposition kinetic equation determined pseudo first order and k=0.0407.