Steam-Assisted Synthesis of Hectorite Loaded with Fe2O3 and Its Catalytic Fenton Degradation of Phenol

Abstract

Fe2O3 loaded in the interlayer of hectorite was synthesized using a steam-assisted one-pot method to replace the traditional high-temperature and high-pressure hydrothermal method. The samples were characterized by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and N2 adsorption–desorption isotherms. Fe2O3/hectorite had a layered hectorite structure. Due to the insertion of Fe2O3, the interlayer spacing increased and had a large specific surface area and pore size, benefiting catalytic reactions. Fe2O3/hectorite was used as a catalyst to degrade phenol in wastewater via the Fenton reaction. With this catalyst, the optimal Fenton reaction conditions were determined with an orthogonal test: pH, 3; temperature, 60 °C; and catalyst dosage, 0.5 g dm−3. Under these optimal reaction conditions, the degradation rate of phenol (200 mg dm–3) was 99.27% in 3 h. After five cycles, the degradation rate reached 95.72%, indicating the excellent reusability of this catalyst. In the temperature range 303–330 K, the catalytic degradation kinetics were studied as a pseudo-first-order reaction, and the apparent activation energy was 30.71 kJ/mol.