Optimization of Photocatalytic Degradation of Phenol Via Fe3O4@SiO2@TiO2 Magnetic Nanocomposite by Response Surface Methodology

Phenol removal has recently become a topic of interest and debate among environmental scientists. In this research, the efficiency of Fe3O4@SiO2@TiO2 magnetic photocatalyst in phenol degradation was evaluated. Also, the effect of effective factors in the degradation of this pollutant was investigated using the surface response methodology. In the present work, photodegradation of phenol in an aqueous solution was studied using Fe3O4@SiO2@TiO2 nanocomposite under ultraviolet. The as-synthesized materials were characterized by UV-Visible diffuse reflectance spectra, scanning electron microscope, Fourier transform infrared,X-ray diffraction, and vibrating sample magnetometer. Based on XRD and VSM, the Fe3O4@SiO2@TiO2 nanocomposite structure contained an anatase TiO2 phase and showed a superparamagnetic behavior (12.07 emu/g). Based on the DRS spectra and bandgap computation, the direct bandgap energy of Fe3O4@SiO2@TiO2 was 3.01 eV. Result of ANOVA showed that the effects of the main variables of photocatalyst concentration, UV light irradiation time and the square of photocatalyst concentration are significant in the model. Significant variables from the most significant to the least significant include: photocatalyst concentration>UV light irradiation time>square of photocatalyst concentration. The findings showed that Fe3O4@SiO2@TiO2 was recycled five times to attain 50% degradation of phenol and the photocatalytic activity did not decrease noticeably after five photocatalytic cycles. The Photocatalytic degradation of phenol was performed by the response surface methodology to study the influence of operational factors on the degradation process. Maximum removal of 55% phenol was obtained at a pH of 8, a photocatalyst dosage of 1.0 g/L, and a phenol concentration of 100 mg/L after 220 min UV irradiation time. Results showed that the Fe3O4@SiO2@TiO2 magnetic nanocomposite has suitable potential for treating phenolic wastewater.